Cryptosporidium/Cryptosporidiosis

General Characteristics of Cryptosporidium

• Genus Cryptosporidium Cryptosporidium A genus of coccidian parasites of the family cryptosporidiidae, found in the intestinal epithelium of many vertebrates including humans. Hyper-IgM Syndrome: 
  • Apicomplexan protozoan parasite
  • > 30 species
  • Clinically relevant species (cause > 90% of human infections Infections Invasion of the host organism by microorganisms or their toxins or by parasites that can cause pathological conditions or diseases. Chronic Granulomatous Disease):
    • Cryptosporidium Cryptosporidium A genus of coccidian parasites of the family cryptosporidiidae, found in the intestinal epithelium of many vertebrates including humans. Hyper-IgM Syndrome hominis (previously, C. parvum genotype Genotype The genetic constitution of the individual, comprising the alleles present at each genetic locus. Basic Terms of Genetics 1)
    • Cryptosporidium Cryptosporidium A genus of coccidian parasites of the family cryptosporidiidae, found in the intestinal epithelium of many vertebrates including humans. Hyper-IgM Syndrome parvum (previously, C. parvum genotype Genotype The genetic constitution of the individual, comprising the alleles present at each genetic locus. Basic Terms of Genetics 2)
• Causes the disease cryptosporidiosis
• Fecal–oral transmission
• Life cycle requires only a single host (monoxenous).
• Organism does not multiply outside the host.
• Oocysts exist in 2 morphologic forms:
  • Thin-walled structures, which remain in the host and cause autoinoculation Autoinoculation Molluscum Contagiosum (infection of nearby host cells)
  • Thick-walled structures, which exit the host in feces
• Infections Infections Invasion of the host organism by microorganisms or their toxins or by parasites that can cause pathological conditions or diseases. Chronic Granulomatous Disease are zoonotic or anthroponotic. 

Epidemiology and Risk Factors

Epidemiology

• Important cause of diarrhea Diarrhea Diarrhea is defined as ≥ 3 watery or loose stools in a 24-hour period. There are a multitude of etiologies, which can be classified based on the underlying mechanism of disease. The duration of symptoms (acute or chronic) and characteristics of the stools (e.g., watery, bloody, steatorrheic, mucoid) can help guide further diagnostic evaluation. Diarrhea in both children and adults worldwide 
• 2nd most common cause of moderate to severe diarrheal disease in children < 24 months of age in Africa and Asia ASIA Spinal Cord Injuries
• Incidence Incidence The number of new cases of a given disease during a given period in a specified population. It also is used for the rate at which new events occur in a defined population. It is differentiated from prevalence, which refers to all cases in the population at a given time. Measures of Disease Frequency by age:
  • Most common: children < 5 years
  • 2nd most common: women of childbearing age 
  • Uncommon in immunocompetent adults in resource-rich countries
• Seroprevalence Seroprevalence Herpes Simplex Virus 1 and 2 (i.e. cryptosporidiosis at some point in life) in the US: estimated at 25%‒35%
• Groups with increased prevalence Prevalence The total number of cases of a given disease in a specified population at a designated time. It is differentiated from incidence, which refers to the number of new cases in the population at a given time. Measures of Disease Frequency:
  • Immunocompromised immunocompromised A human or animal whose immunologic mechanism is deficient because of an immunodeficiency disorder or other disease or as the result of the administration of immunosuppressive drugs or radiation. Gastroenteritis patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship
  • Dairy farmers
• Infection is most common in:
  • Warm climates/conditions:
    • Infections Infections Invasion of the host organism by microorganisms or their toxins or by parasites that can cause pathological conditions or diseases. Chronic Granulomatous Disease in the US peak in July‒September.
    • Infections Infections Invasion of the host organism by microorganisms or their toxins or by parasites that can cause pathological conditions or diseases. Chronic Granulomatous Disease in the UK peak in spring (associated with C. parvum and farm animals Animals Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, animalia was one of the kingdoms. Under the modern three domain model, animalia represents one of the many groups in the domain eukaryota. Cell Types: Eukaryotic versus Prokaryotic) and fall (associated with C. hominis and recreational water).
  • Rainy periods in endemic areas

Risk factors

• Overcrowding 
• Poor sanitary conditions (open sites of defecation Defecation The normal process of elimination of fecal material from the rectum. Gastrointestinal Motility) 
• Animal contact with infected animals Animals Unicellular or multicellular, heterotrophic organisms, that have sensation and the power of voluntary movement. Under the older five kingdom paradigm, animalia was one of the kingdoms. Under the modern three domain model, animalia represents one of the many groups in the domain eukaryota. Cell Types: Eukaryotic versus Prokaryotic
• Consumption of unfiltered and untreated water 
• Swallowing Swallowing The act of taking solids and liquids into the gastrointestinal tract through the mouth and throat. Gastrointestinal Motility contaminated recreational water (i.e. from swimming pools)
• Exposure to fecal material through sexual contact
• Immunosuppression/immunodeficiencies, including:
  • HIV HIV Anti-HIV Drugs patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship with CD4 count < 100 cells/μL
  • Immunosuppressive therapy/organ transplant recipients
  • Cancer
  • Hypogammaglobulinemia Hypogammaglobulinemia Selective IgA Deficiency

Pathophysiology

Reservoirs

• C. hominis primarily infects humans
• C. parvum primarily infects humans and other mammals, particularly livestock
• Other species of Cryptosporidium Cryptosporidium A genus of coccidian parasites of the family cryptosporidiidae, found in the intestinal epithelium of many vertebrates including humans. Hyper-IgM Syndrome infect:
  • Humans
  • Other mammals (livestock, rodents, cats, dogs, and guinea pigs)
  • Birds
  • Reptiles and fish FISH A type of in situ hybridization in which target sequences are stained with fluorescent dye so their location and size can be determined using fluorescence microscopy. This staining is sufficiently distinct that the hybridization signal can be seen both in metaphase spreads and in interphase nuclei. Chromosome Testing

Transmission

Transmission is by the fecal–oral route. Ingestion of Cryptosporidium Cryptosporidium A genus of coccidian parasites of the family cryptosporidiidae, found in the intestinal epithelium of many vertebrates including humans. Hyper-IgM Syndrome oocysts initiates infection. The different sources of transmission are: 

• Contaminated water:
  • Common sources:
    • Swimming pools (recreational water-associated outbreaks Outbreaks Sudden increase in the incidence of a disease. The concept includes epidemics and pandemics. Influenza Viruses/Influenza)
    • Contaminated drinking water
    • Natural ponds
  • Responsible for community outbreaks Outbreaks Sudden increase in the incidence of a disease. The concept includes epidemics and pandemics. Influenza Viruses/Influenza and travelers’ diarrhea Diarrhea Diarrhea is defined as ≥ 3 watery or loose stools in a 24-hour period. There are a multitude of etiologies, which can be classified based on the underlying mechanism of disease. The duration of symptoms (acute or chronic) and characteristics of the stools (e.g., watery, bloody, steatorrheic, mucoid) can help guide further diagnostic evaluation. Diarrhea
  • Oocysts are present in a majority of surface water bodies.
  • Eradication of oocysts is difficult because they are resistant to a large number of disinfectants, including chlorine.
• Person-to-person contact: 
  • Commonly spreads among:
    • Household members 
    • Sexual partners 
    • Children in daycare centers 
    • Caretakers of children in the susceptible age groups 
    • Healthcare workers
  • C. hominis and C. parvum are both involved in person-to-person transmission.
• Animal contact: 
  • Exposure to animal feces infected with oocysts 
  • Commonly spreads among:
    • Veterinary students 
    • Dairy farmers 
• Contaminated food: 
  • Exposure less common than waterborne outbreaks Outbreaks Sudden increase in the incidence of a disease. The concept includes epidemics and pandemics. Influenza Viruses/Influenza 
  • Outbreaks Outbreaks Sudden increase in the incidence of a disease. The concept includes epidemics and pandemics. Influenza Viruses/Influenza have been reported in the literature in association with:
    • Raw produce
    • Unpasteurized goat and cow milk
    • Apple cider
    • Barbecued meat

Life Cycle

Infection is initiated by the ingestion of fully sporulated and environment-resistant oocysts. 

1. Oocysts activated in the stomach Stomach The stomach is a muscular sac in the upper left portion of the abdomen that plays a critical role in digestion. The stomach develops from the foregut and connects the esophagus with the duodenum. Structurally, the stomach is C-shaped and forms a greater and lesser curvature and is divided grossly into regions: the cardia, fundus, body, and pylorus. Stomach: Anatomy and upper intestine → excystation Excystation Giardia/Giardiasis, releasing 4 motile sporozoites Sporozoites The product of meiotic division of zygotes in parasitic protozoa comprising haploid cells. These infective cells invade the host and undergo asexual reproduction producing merozoites (or other forms) and ultimately gametocytes. Antimalarial Drugs
2. Sporozoites Sporozoites The product of meiotic division of zygotes in parasitic protozoa comprising haploid cells. These infective cells invade the host and undergo asexual reproduction producing merozoites (or other forms) and ultimately gametocytes. Antimalarial Drugs penetrate the mucous layer and attach to brush border Brush border Tubular System enterocytes.
3. A vacuole forms around the parasite:
   • Located within the host cell’s plasma membrane Plasma membrane A cell membrane (also known as the plasma membrane or plasmalemma) is a biological membrane that separates the cell contents from the outside environment. A cell membrane is composed of a phospholipid bilayer and proteins that function to protect cellular DNA and mediate the exchange of ions and molecules. The Cell: Cell Membrane but outside the cytoplasm
   • Triggers differentiation of sporozoites Sporozoites The product of meiotic division of zygotes in parasitic protozoa comprising haploid cells. These infective cells invade the host and undergo asexual reproduction producing merozoites (or other forms) and ultimately gametocytes. Antimalarial Drugs into trophozoites Trophozoites Cells or feeding stage in the life cycle of sporozoan protozoa. In the malarial parasite, the trophozoite develops from the merozoite and then splits into the schizont. Trophozoites that are left over from cell division can go on to form gametocytes. Amebicides 
4. Asexual reproduction ( mitosis Mitosis A type of cell nucleus division by means of which the two daughter nuclei normally receive identical complements of the number of chromosomes of the somatic cells of the species. Cell Cycle) within the vacuole leads to formation of a type I meront, which ultimately produces 6‒8 type I merozoites Merozoites Uninuclear cells or a stage in the life cycle of sporozoan protozoa. Merozoites, released from ruptured multinucleate schizonts, enter the bloodstream and infect the erythrocytes. Plasmodium/Malaria (similar to sporozoites Sporozoites The product of meiotic division of zygotes in parasitic protozoa comprising haploid cells. These infective cells invade the host and undergo asexual reproduction producing merozoites (or other forms) and ultimately gametocytes. Antimalarial Drugs).
5. Merozoites Merozoites Uninuclear cells or a stage in the life cycle of sporozoan protozoa. Merozoites, released from ruptured multinucleate schizonts, enter the bloodstream and infect the erythrocytes. Plasmodium/Malaria escape Escape With constant immune mechanisms holding unstable tumor cells in equilibrium, tumor-cell variants may emerge. These cancer cells may express fewer antigens on their surfaces or lose their MHC class I expression.Variants may also protect themselves from T-cell attack via expression of IC molecules on their surfaces, like normal cells.Creation of an immunosuppressive state in the microenvironment is another way to grow without immunologic interference. Cancer Immunotherapy the vacuole and either:
   • Continue asexual reproduction cycles: attach to enterocytes → vacuole formation → type I meront → merozoites Merozoites Uninuclear cells or a stage in the life cycle of sporozoan protozoa. Merozoites, released from ruptured multinucleate schizonts, enter the bloodstream and infect the erythrocytes. Plasmodium/Malaria
   • Enter the sexual reproduction cycle: form a type II meront → produces 4 type II merozoites Merozoites Uninuclear cells or a stage in the life cycle of sporozoan protozoa. Merozoites, released from ruptured multinucleate schizonts, enter the bloodstream and infect the erythrocytes. Plasmodium/Malaria
6. Type II merozoites Merozoites Uninuclear cells or a stage in the life cycle of sporozoan protozoa. Merozoites, released from ruptured multinucleate schizonts, enter the bloodstream and infect the erythrocytes. Plasmodium/Malaria:
   • Infect nearby enterocytes
   • Form an undifferentiated gamete Gamete Gametogenesis that eventually produces either a:
     • Macrogamont (female) 
     • Microgamont (male) 
7. The microgamont releases ≥ 16 microgametes, each of which fertilizes a macrogamont to form a diploid Diploid The chromosomal constitution of cells, in which each type of chromosome is represented twice. Symbol: 2n or 2x. Basic Terms of Genetics zygote Zygote The fertilized ovum resulting from the fusion of a male and a female gamete. Fertilization and First Week.
8. The diploid Diploid The chromosomal constitution of cells, in which each type of chromosome is represented twice. Symbol: 2n or 2x. Basic Terms of Genetics zygote Zygote The fertilized ovum resulting from the fusion of a male and a female gamete. Fertilization and First Week differentiates into an oocyst Oocyst Zygote-containing cysts of sporozoan protozoa. Further development in an oocyst produces small individual infective organisms called sporozoites. Then, depending on the genus, the entire oocyst is called a sporocyst or the oocyst contains multiple sporocysts encapsulating the sporozoites. Toxoplasma/Toxoplasmosis, which may be:
   • Thin-walled (20%) → remains in the host and causes autoinfection Autoinfection Enterobius/Enterobiasis (infection of nearby host cells)
   • Thick-walled (80%) → excreted from the host in feces

Pathogenesis

Cryptosporidium Cryptosporidium A genus of coccidian parasites of the family cryptosporidiidae, found in the intestinal epithelium of many vertebrates including humans. Hyper-IgM Syndrome causes secretory diarrhea Diarrhea Diarrhea is defined as ≥ 3 watery or loose stools in a 24-hour period. There are a multitude of etiologies, which can be classified based on the underlying mechanism of disease. The duration of symptoms (acute or chronic) and characteristics of the stools (e.g., watery, bloody, steatorrheic, mucoid) can help guide further diagnostic evaluation. Diarrhea associated with malabsorption Malabsorption General term for a group of malnutrition syndromes caused by failure of normal intestinal absorption of nutrients. Malabsorption and Maldigestion.

• Location of the parasite:
  • Implants in the intestinal epithelial cells (enterocytes) 
  • Intracellular but extracytoplasmic
• Parasitic implantation Implantation Endometrial implantation of embryo, mammalian at the blastocyst stage. Fertilization and First Week → distortion Distortion Defense Mechanisms of the microvilli (may cause inflammation Inflammation Inflammation is a complex set of responses to infection and injury involving leukocytes as the principal cellular mediators in the body’s defense against pathogenic organisms. Inflammation is also seen as a response to tissue injury in the process of wound healing. The 5 cardinal signs of inflammation are pain, heat, redness, swelling, and loss of function. Inflammation) → interferes with absorption Absorption Absorption involves the uptake of nutrient molecules and their transfer from the lumen of the GI tract across the enterocytes and into the interstitial space, where they can be taken up in the venous or lymphatic circulation. Digestion and Absorption and secretion Secretion Coagulation Studies → secretory diarrhea Diarrhea Diarrhea is defined as ≥ 3 watery or loose stools in a 24-hour period. There are a multitude of etiologies, which can be classified based on the underlying mechanism of disease. The duration of symptoms (acute or chronic) and characteristics of the stools (e.g., watery, bloody, steatorrheic, mucoid) can help guide further diagnostic evaluation. Diarrhea
• Typical findings include:
  • Increased intestinal permeability/reduced barrier function 
  • Chloride Chloride Inorganic compounds derived from hydrochloric acid that contain the Cl- ion. Electrolytes secretion Secretion Coagulation Studies 
  • Crypt hyperplasia Crypt hyperplasia Celiac Disease 
  • Villous atrophy Villous Atrophy Giardia/Giardiasis → ↓ absorptive surface area
  • Glucose Glucose A primary source of energy for living organisms. It is naturally occurring and is found in fruits and other parts of plants in its free state. It is used therapeutically in fluid and nutrient replacement. Lactose Intolerance malabsorption Malabsorption General term for a group of malnutrition syndromes caused by failure of normal intestinal absorption of nutrients. Malabsorption and Maldigestion
• Extent of disease:
  • Immunocompetent patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship → infection is typically limited to the small intestine Small intestine The small intestine is the longest part of the GI tract, extending from the pyloric orifice of the stomach to the ileocecal junction. The small intestine is the major organ responsible for chemical digestion and absorption of nutrients. It is divided into 3 segments: the duodenum, the jejunum, and the ileum. Small Intestine: Anatomy.
  • Immunocompromised immunocompromised A human or animal whose immunologic mechanism is deficient because of an immunodeficiency disorder or other disease or as the result of the administration of immunosuppressive drugs or radiation. Gastroenteritis patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship → infection may involve:
    • Biliary tract Biliary tract Bile is secreted by hepatocytes into thin channels called canaliculi. These canaliculi lead into slightly larger interlobular bile ductules, which are part of the portal triads at the “corners” of hepatic lobules. The bile leaves the liver via the right and left hepatic ducts, which join together to form the common hepatic duct. Gallbladder and Biliary Tract: Anatomy and liver Liver The liver is the largest gland in the human body. The liver is found in the superior right quadrant of the abdomen and weighs approximately 1.5 kilograms. Its main functions are detoxification, metabolism, nutrient storage (e.g., iron and vitamins), synthesis of coagulation factors, formation of bile, filtration, and storage of blood. Liver: Anatomy
    • Pancreas Pancreas The pancreas lies mostly posterior to the stomach and extends across the posterior abdominal wall from the duodenum on the right to the spleen on the left. This organ has both exocrine and endocrine tissue. Pancreas: Anatomy
    • Gastric mucosa Gastric mucosa Lining of the stomach, consisting of an inner epithelium, a middle lamina propria, and an outer muscularis mucosae. The surface cells produce mucus that protects the stomach from attack by digestive acid and enzymes. When the epithelium invaginates into the lamina propria at various region of the stomach (cardia; gastric fundus; and pylorus), different tubular gastric glands are formed. These glands consist of cells that secrete mucus, enzymes, hydrochloric acid, or hormones. Stomach: Anatomy
    • Respiratory tract

Clinical Presentation

Spectrum of disease

• Asymptomatic
• Mild: self-limited diarrhea Diarrhea Diarrhea is defined as ≥ 3 watery or loose stools in a 24-hour period. There are a multitude of etiologies, which can be classified based on the underlying mechanism of disease. The duration of symptoms (acute or chronic) and characteristics of the stools (e.g., watery, bloody, steatorrheic, mucoid) can help guide further diagnostic evaluation. Diarrhea
• Severe: significant enteritis Enteritis Inflammation of any segment of the small intestine. Lactose Intolerance, potentially with extraintestinal involvement

Disease course

• Incubation Incubation The amount time between exposure to an infectious agent and becoming symptomatic. Rabies Virus period: about 5‒10 days
• Typically, lasts 10‒14 days (self-limited)
• May become chronic in immunocompromised immunocompromised A human or animal whose immunologic mechanism is deficient because of an immunodeficiency disorder or other disease or as the result of the administration of immunosuppressive drugs or radiation. Gastroenteritis patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship

Symptoms

Symptomatic cryptosporidiosis presents with: 

• Diarrhea Diarrhea Diarrhea is defined as ≥ 3 watery or loose stools in a 24-hour period. There are a multitude of etiologies, which can be classified based on the underlying mechanism of disease. The duration of symptoms (acute or chronic) and characteristics of the stools (e.g., watery, bloody, steatorrheic, mucoid) can help guide further diagnostic evaluation. Diarrhea:
  • Most common: profuse and watery (up to 25 L/day) → may lead to volume depletion Volume depletion Volume status is a balance between water and solutes, the majority of which is Na. Volume depletion refers to a loss of both water and Na, whereas dehydration refers only to a loss of water. Volume depletion can be caused by GI losses, renal losses, bleeding, poor oral Na intake, or third spacing of fluids. Volume Depletion and Dehydration
  • Intermittent or continuous
• Malaise Malaise Tick-borne Encephalitis Virus 
• Nausea Nausea An unpleasant sensation in the stomach usually accompanied by the urge to vomit. Common causes are early pregnancy, sea and motion sickness, emotional stress, intense pain, food poisoning, and various enteroviruses. Antiemetics 
• Anorexia Anorexia The lack or loss of appetite accompanied by an aversion to food and the inability to eat. It is the defining characteristic of the disorder anorexia nervosa. Anorexia Nervosa 
• Crampy abdominal pain Abdominal Pain Acute Abdomen 
• Low-grade fever Low-Grade Fever Erythema Infectiosum 
• Immunocompromised immunocompromised A human or animal whose immunologic mechanism is deficient because of an immunodeficiency disorder or other disease or as the result of the administration of immunosuppressive drugs or radiation. Gastroenteritis patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship may also present with extraintestinal disease:
  • Cholecystitis Cholecystitis Cholecystitis is the inflammation of the gallbladder (GB) usually caused by the obstruction of the cystic duct (acute cholecystitis). Mechanical irritation by gallstones can also produce chronic GB inflammation. Cholecystitis is one of the most common complications of cholelithiasis but inflammation without gallstones can occur in a minority of patients. Cholecystitis 
  • Cholangitis 
  • Hepatitis 
  • Pancreatitis Pancreatitis Inflammation of the pancreas. Pancreatitis is classified as acute unless there are computed tomographic or endoscopic retrograde cholangiopancreatographic findings of chronic pancreatitis. The two most common forms of acute pancreatitis are alcoholic pancreatitis and gallstone pancreatitis. Acute Pancreatitis 
  • Pulmonary disease Pulmonary disease Diseases involving the respiratory system. Blastomyces/Blastomycosis

Complications

Cryptosporidiosis is associated with the following complications (more commonly in immunocompromised immunocompromised A human or animal whose immunologic mechanism is deficient because of an immunodeficiency disorder or other disease or as the result of the administration of immunosuppressive drugs or radiation. Gastroenteritis patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship):

• Long-term sequelae (symptoms persist after resolution of acute infection):
  • Abdominal pain Abdominal Pain Acute Abdomen 
  • Diarrhea Diarrhea Diarrhea is defined as ≥ 3 watery or loose stools in a 24-hour period. There are a multitude of etiologies, which can be classified based on the underlying mechanism of disease. The duration of symptoms (acute or chronic) and characteristics of the stools (e.g., watery, bloody, steatorrheic, mucoid) can help guide further diagnostic evaluation. Diarrhea 
  • Irritable bowel syndrome Irritable bowel syndrome Irritable bowel syndrome (IBS) is a functional bowel disease characterized by chronic abdominal pain and altered bowel habits without an identifiable organic cause. The etiology and pathophysiology of this disease are not well understood, and there are many factors that may contribute. Irritable Bowel Syndrome ( IBS IBS Irritable bowel syndrome (IBS) is a functional bowel disease characterized by chronic abdominal pain and altered bowel habits without an identifiable organic cause. The etiology and pathophysiology of this disease are not well understood, and there are many factors that may contribute. Irritable Bowel Syndrome)
  • Weight loss Weight loss Decrease in existing body weight. Bariatric Surgery
  • Joint pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways 
  • Eye pain Pain An unpleasant sensation induced by noxious stimuli which are detected by nerve endings of nociceptive neurons. Pain: Types and Pathways 
  • Headaches and dizziness Dizziness An imprecise term which may refer to a sense of spatial disorientation, motion of the environment, or lightheadedness. Lateral Medullary Syndrome (Wallenberg Syndrome) 
  • Fatigue Fatigue The state of weariness following a period of exertion, mental or physical, characterized by a decreased capacity for work and reduced efficiency to respond to stimuli. Fibromyalgia 
• AIDS cholangiopathy AIDS cholangiopathy AIDS-defining Conditions: 
  • Chronic infection in the biliary tract Biliary tract Bile is secreted by hepatocytes into thin channels called canaliculi. These canaliculi lead into slightly larger interlobular bile ductules, which are part of the portal triads at the “corners” of hepatic lobules. The bile leaves the liver via the right and left hepatic ducts, which join together to form the common hepatic duct. Gallbladder and Biliary Tract: Anatomy → chronic inflammation Chronic Inflammation Inflammation → biliary stricture Stricture Primary Sclerosing Cholangitis and obstruction 
  • Cryptosporidium Cryptosporidium A genus of coccidian parasites of the family cryptosporidiidae, found in the intestinal epithelium of many vertebrates including humans. Hyper-IgM Syndrome is the most common pathogen.
  • May progress to sclerosing cholangitis → cholestasis and hepatic failure Hepatic failure Severe inability of the liver to perform its normal metabolic functions, as evidenced by severe jaundice and abnormal serum levels of ammonia; bilirubin; alkaline phosphatase; aspartate aminotransferase; lactate dehydrogenases; and albumin/globulin ratio. Autoimmune Hepatitis 
  • Increases risk for cholangiocarcinoma Cholangiocarcinoma A malignant tumor arising from the epithelium of the bile ducts. Rare Malignant Liver Tumors

Diagnosis

Stool tests do not regularly check for cryptosporidiosis unless there is a diarrhea Diarrhea Diarrhea is defined as ≥ 3 watery or loose stools in a 24-hour period. There are a multitude of etiologies, which can be classified based on the underlying mechanism of disease. The duration of symptoms (acute or chronic) and characteristics of the stools (e.g., watery, bloody, steatorrheic, mucoid) can help guide further diagnostic evaluation. Diarrhea outbreak. If suspected, specific testing for Cryptosporidium Cryptosporidium A genus of coccidian parasites of the family cryptosporidiidae, found in the intestinal epithelium of many vertebrates including humans. Hyper-IgM Syndrome should be requested when samples are sent to the laboratory.

Diagnostic methods

• Microscopy with a modified Ziehl-Neelsen (MZN) acid-fast stain Acid-Fast Stain Meningitis in Children:
  • Looks for parasitic oocysts
  • Oocysts stain red or pink.
  • 4‒6 μm in diameter
• Direct immunofluorescence assay (DFA): 
  • Fluorescein-labeled antibodies Antibodies Immunoglobulins (Igs), also known as antibodies, are glycoprotein molecules produced by plasma cells that act in immune responses by recognizing and binding particular antigens. The various Ig classes are IgG (the most abundant), IgM, IgE, IgD, and IgA, which differ in their biologic features, structure, target specificity, and distribution. Immunoglobulins: Types and Functions directed against cell wall Cell wall The outermost layer of a cell in most plants; bacteria; fungi; and algae. The cell wall is usually a rigid structure that lies external to the cell membrane, and provides a protective barrier against physical or chemical agents. Cell Types: Eukaryotic versus Prokaryotic antigens of oocysts 
  • Considered the gold standard in the diagnosis of cryptosporidiosis
• Enzyme-linked immunosorbent assay ( ELISA ELISA An immunoassay utilizing an antibody labeled with an enzyme marker such as horseradish peroxidase. While either the enzyme or the antibody is bound to an immunosorbent substrate, they both retain their biologic activity; the change in enzyme activity as a result of the enzyme-antibody-antigen reaction is proportional to the concentration of the antigen and can be measured spectrophotometrically or with the naked eye. Many variations of the method have been developed. St. Louis Encephalitis Virus): 
  • Commonly used in epidemiologic investigations
  • Not as sensitive as PCR PCR Polymerase chain reaction (PCR) is a technique that amplifies DNA fragments exponentially for analysis. The process is highly specific, allowing for the targeting of specific genomic sequences, even with minuscule sample amounts. The PCR cycles multiple times through 3 phases: denaturation of the template DNA, annealing of a specific primer to the individual DNA strands, and synthesis/elongation of new DNA molecules. Polymerase Chain Reaction (PCR)
• Polymerase chain reaction Polymerase chain reaction Polymerase chain reaction (PCR) is a technique that amplifies DNA fragments exponentially for analysis. The process is highly specific, allowing for the targeting of specific genomic sequences, even with minuscule sample amounts. The PCR cycles multiple times through 3 phases: denaturation of the template DNA, annealing of a specific primer to the individual DNA strands, and synthesis/elongation of new DNA molecules. Polymerase Chain Reaction (PCR) ( PCR PCR Polymerase chain reaction (PCR) is a technique that amplifies DNA fragments exponentially for analysis. The process is highly specific, allowing for the targeting of specific genomic sequences, even with minuscule sample amounts. The PCR cycles multiple times through 3 phases: denaturation of the template DNA, annealing of a specific primer to the individual DNA strands, and synthesis/elongation of new DNA molecules. Polymerase Chain Reaction (PCR)): 
  • Highly sensitive 
  • Can differentiate between the different genotypes of Cryptosporidium Cryptosporidium A genus of coccidian parasites of the family cryptosporidiidae, found in the intestinal epithelium of many vertebrates including humans. Hyper-IgM Syndrome. 
  • Useful tool in epidemiologic investigations. 
• Histopathology of Cryptosporidium Cryptosporidium A genus of coccidian parasites of the family cryptosporidiidae, found in the intestinal epithelium of many vertebrates including humans. Hyper-IgM Syndrome (H&E stain):
  • Basophilic appearance
  • Solitary, or occur in clusters
  • Present on the brush border Brush border Tubular System of the mucosal surface
  • Typically, less sensitive than stool examination, since infections Infections Invasion of the host organism by microorganisms or their toxins or by parasites that can cause pathological conditions or diseases. Chronic Granulomatous Disease can be “patchy” throughout the intestines
• Testing samples:
  • Stool:
    • Most common; typically 1st sample ordered
    • Collecting specimens over 3 days increases sensitivity because excretion of oocysts is intermittent.
  • Duodenal aspirate
  • Bile Bile An emulsifying agent produced in the liver and secreted into the duodenum. Its composition includes bile acids and salts; cholesterol; and electrolytes. It aids digestion of fats in the duodenum. Gallbladder and Biliary Tract: Anatomy secretions 
  • Biopsy Biopsy Removal and pathologic examination of specimens from the living body. Ewing Sarcoma of affected GI tissue 
  • Respiratory secretions

Imaging

• Nonspecific findings, but can aid in diagnosis 
• CT, abdominal radiography, or abdominal ultrasonography may show:
  • Distention of bowel loops 
  • Air–fluid levels
  • Enlarged gallbladder Gallbladder The gallbladder is a pear-shaped sac, located directly beneath the liver, that sits on top of the superior part of the duodenum. The primary functions of the gallbladder include concentrating and storing up to 50 mL of bile. Gallbladder and Biliary Tract: Anatomy
  • Dilated or irregular biliary ducts
• Endoscopic retrograde cholangiopancreatography Endoscopic Retrograde Cholangiopancreatography Fiberoptic endoscopy designed for duodenal observation and cannulation of Vater’s ampulla, in order to visualize the pancreatic and biliary duct system by retrograde injection of contrast media. Endoscopic (Vater) papillotomy may be performed during this procedure. Primary Sclerosing Cholangitis ( ERCP ERCP Fiberoptic endoscopy designed for duodenal observation and cannulation of vater’s ampulla, in order to visualize the pancreatic and biliary duct system by retrograde injection of contrast media. Endoscopic (vater) papillotomy may be performed during this procedure. Primary Sclerosing Cholangitis) or magnetic resonance cholangiopancreatography Magnetic resonance cholangiopancreatography Non-invasive diagnostic technique for visualizing the pancreatic ducts and bile ducts without the use of injected contrast media or x-ray. Mri scans provide excellent sensitivity for duct dilatation, biliary stricture, and intraductal abnormalities. Primary Sclerosing Cholangitis ( MRCP MRCP Non-invasive diagnostic technique for visualizing the pancreatic ducts and bile ducts without the use of injected contrast media or x-ray. Mri scans provide excellent sensitivity for duct dilatation, biliary stricture, and intraductal abnormalities. Primary Sclerosing Cholangitis):
  • Consider when biliary disease is suspected
  • May allow for simultaneous therapeutic intervention

Serologic testing

In cases with significant diarrhea Diarrhea Diarrhea is defined as ≥ 3 watery or loose stools in a 24-hour period. There are a multitude of etiologies, which can be classified based on the underlying mechanism of disease. The duration of symptoms (acute or chronic) and characteristics of the stools (e.g., watery, bloody, steatorrheic, mucoid) can help guide further diagnostic evaluation. Diarrhea:

• Electrolytes Electrolytes Electrolytes are mineral salts that dissolve in water and dissociate into charged particles called ions, which can be either be positively (cations) or negatively (anions) charged. Electrolytes are distributed in the extracellular and intracellular compartments in different concentrations. Electrolytes are essential for various basic life-sustaining functions. Electrolytes (assess need for repletion, volume status Volume Status ACES and RUSH: Resuscitation Ultrasound Protocols)
• Hepatic function tests/pancreatic enzymes Enzymes Enzymes are complex protein biocatalysts that accelerate chemical reactions without being consumed by them. Due to the body’s constant metabolic needs, the absence of enzymes would make life unsustainable, as reactions would occur too slowly without these molecules. Basics of Enzymes (assess potential hepatic/pancreatic involvement)
• HIV HIV Anti-HIV Drugs testing in patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship with prolonged cryptosporidiosis

Management and Prevention

Management

Most patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship are asymptomatic or have mild disease. Supportive treatment is the main approach.

• Fluid and electrolyte replacement → to compensate for the volume loss due to severe diarrhea Diarrhea Diarrhea is defined as ≥ 3 watery or loose stools in a 24-hour period. There are a multitude of etiologies, which can be classified based on the underlying mechanism of disease. The duration of symptoms (acute or chronic) and characteristics of the stools (e.g., watery, bloody, steatorrheic, mucoid) can help guide further diagnostic evaluation. Diarrhea, including:
  • Volume repletion (oral or IV)
  • Electrolytes Electrolytes Electrolytes are mineral salts that dissolve in water and dissociate into charged particles called ions, which can be either be positively (cations) or negatively (anions) charged. Electrolytes are distributed in the extracellular and intracellular compartments in different concentrations. Electrolytes are essential for various basic life-sustaining functions. Electrolytes ( sodium Sodium A member of the alkali group of metals. It has the atomic symbol na, atomic number 11, and atomic weight 23. Hyponatremia, potassium Potassium An element in the alkali group of metals with an atomic symbol k, atomic number 19, and atomic weight 39. 10. It is the chief cation in the intracellular fluid of muscle and other cells. Potassium ion is a strong electrolyte that plays a significant role in the regulation of fluid volume and maintenance of the water-electrolyte balance. Hyperkalemia, and bicarbonate Bicarbonate Inorganic salts that contain the -HCO3 radical. They are an important factor in determining the ph of the blood and the concentration of bicarbonate ions is regulated by the kidney. Levels in the blood are an index of the alkali reserve or buffering capacity. Electrolytes)
  • Glucose Glucose A primary source of energy for living organisms. It is naturally occurring and is found in fruits and other parts of plants in its free state. It is used therapeutically in fluid and nutrient replacement. Lactose Intolerance 
• Nutritional support:
  • Lactose-free diet until recovered
  • Consider parenteral nutrition Parenteral nutrition The administering of nutrients for assimilation and utilization by a patient who cannot maintain adequate nutrition by enteral feeding alone. Nutrients are administered by a route other than the alimentary canal (e.g., intravenously, subcutaneously). Central Venous Catheter in patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship with chronic persistence of symptoms (> 4‒6 weeks), which is associated with cachexia. 
• Antidiarrheal Antidiarrheal Antidiarrheal agents include several drug classes, including opioid agonists, somatostatin analogues, adsorbents, and bile acid sequestrants. These medications mainly work through antimotility and/or antisecretory effects. Antidiarrheal Drugs agents (administered in the event of excessive fluid loss):
  • Loperamide Loperamide One of the long-acting synthetic antidiarrheals; it is not significantly absorbed from the gut, and has no effect on the adrenergic system or central nervous system, but may antagonize histamine and interfere with acetylcholine release locally. Antidiarrheal Drugs (Imodium^®)
  • Combination of diphenoxylate Diphenoxylate A meperidine congener used as an antidiarrheal, usually in combination with atropine. At high doses, it acts like morphine. Its unesterified metabolite difenoxin has similar properties and is used similarly. It has little or no analgesic activity. Antidiarrheal Drugs and atropine Atropine An alkaloid, originally from atropa belladonna, but found in other plants, mainly solanaceae. Hyoscyamine is the 3(s)-endo isomer of atropine. Anticholinergic Drugs (Lomotil^®)
  • Tincture of opium 
  • Octreotide Octreotide A potent, long-acting synthetic somatostatin octapeptide analog that inhibits secretion of growth hormone and is used to treat hormone-secreting tumors; diabetes mellitus; hypotension, orthostatic; hyperinsulinism; hypergastrinemia; and small bowel fistula. Antidiarrheal Drugs (in chronic cryptosporidiosis)
• Antiparasitic agent (nitazoxanide):
  • The only FDA-approved drug in the US for the treatment of cryptosporidiosis
  • Typically, reserved for severe disease and for immunocompromised immunocompromised A human or animal whose immunologic mechanism is deficient because of an immunodeficiency disorder or other disease or as the result of the administration of immunosuppressive drugs or radiation. Gastroenteritis patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship
  • Inhibits the growth of Cryptosporidium Cryptosporidium A genus of coccidian parasites of the family cryptosporidiidae, found in the intestinal epithelium of many vertebrates including humans. Hyper-IgM Syndrome trophozoites Trophozoites Cells or feeding stage in the life cycle of sporozoan protozoa. In the malarial parasite, the trophozoite develops from the merozoite and then splits into the schizont. Trophozoites that are left over from cell division can go on to form gametocytes. Amebicides 
  • Shortens the duration of diarrhea Diarrhea Diarrhea is defined as ≥ 3 watery or loose stools in a 24-hour period. There are a multitude of etiologies, which can be classified based on the underlying mechanism of disease. The duration of symptoms (acute or chronic) and characteristics of the stools (e.g., watery, bloody, steatorrheic, mucoid) can help guide further diagnostic evaluation. Diarrhea
  • Decreases mortality Mortality All deaths reported in a given population. Measures of Health Status in malnourished children
  • Indicated for adults and children > 12 months of age

Treatment of immunocompromised immunocompromised A human or animal whose immunologic mechanism is deficient because of an immunodeficiency disorder or other disease or as the result of the administration of immunosuppressive drugs or radiation. Gastroenteritis patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship

Cryptosporidiosis is one of the opportunistic infections Infections Invasion of the host organism by microorganisms or their toxins or by parasites that can cause pathological conditions or diseases. Chronic Granulomatous Disease that can occur in patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship with HIV HIV Anti-HIV Drugs. 

• Initiate supportive therapy 
• Continue (or initiate) antiretroviral therapy Antiretroviral therapy Antiretroviral therapy (ART) targets the replication cycle of the human immunodeficiency virus (HIV) and is classified based on the viral enzyme or mechanism that is inhibited. The goal of therapy is to suppress viral replication to reach the outcome of undetected viral load. Anti-HIV Drugs (ART) to restore immune function:
  • Often needed to clear infection
  • Aspartyl protease inhibitors Protease Inhibitors Compounds which inhibit or antagonize biosynthesis or actions of proteases (endopeptidases). Anti-HIV Drugs have a beneficial direct effect on the Cryptosporidium Cryptosporidium A genus of coccidian parasites of the family cryptosporidiidae, found in the intestinal epithelium of many vertebrates including humans. Hyper-IgM Syndrome life cycle.
• Administer antiparasitic therapy:
  • Nitazoxanide:
    • Less effective in immunocompromised immunocompromised A human or animal whose immunologic mechanism is deficient because of an immunodeficiency disorder or other disease or as the result of the administration of immunosuppressive drugs or radiation. Gastroenteritis patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship 
    • May be given to patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship with severe disease or persistent symptoms that are not responding to other therapies
  • Paromomycin Paromomycin An aminoglycoside antibacterial and antiprotozoal agent produced by species of streptomyces. Amebicides:
    • A nonabsorbable aminoglycoside with partial activity against Cryptosporidium Cryptosporidium A genus of coccidian parasites of the family cryptosporidiidae, found in the intestinal epithelium of many vertebrates including humans. Hyper-IgM Syndrome
    • Used if nitazoxanide is contraindicated
  • Azithromycin Azithromycin A semi-synthetic macrolide antibiotic structurally related to erythromycin. It has been used in the treatment of Mycobacterium avium intracellulare infections, toxoplasmosis, and cryptosporidiosis. Macrolides and Ketolides:
    • Can be administered in combination with nitazoxanide or paromomycin Paromomycin An aminoglycoside antibacterial and antiprotozoal agent produced by species of streptomyces. Amebicides 
    • Provides symptomatic relief 
• Management of AIDS cholangiopathy AIDS cholangiopathy AIDS-defining Conditions may include:
  • Cholecystectomy Cholecystectomy Cholecystectomy is a surgical procedure performed with the goal of resecting and extracting the gallbladder. It is one of the most common abdominal surgeries performed in the Western world. Cholecystectomy is performed for symptomatic cholelithiasis, cholecystitis, gallbladder polyps > 0.5 cm, porcelain gallbladder, choledocholithiasis and gallstone pancreatitis, and rarely, for gallbladder cancer. Cholecystectomy (to manage acalculous cholecystitis Acalculous cholecystitis Inflammation of the gallbladder wall in the absence of gallstones. Cholecystitis)
  • ERCP ERCP Fiberoptic endoscopy designed for duodenal observation and cannulation of vater’s ampulla, in order to visualize the pancreatic and biliary duct system by retrograde injection of contrast media. Endoscopic (vater) papillotomy may be performed during this procedure. Primary Sclerosing Cholangitis with biliary sphincterotomy Sphincterotomy Surgical incision of a sphincter. Anal Fissure (to manage sclerosing cholangitis)
  • Endoscopic stenting (to manage biliary stricture Stricture Primary Sclerosing Cholangitis) 
  • Ursodeoxycholic acid Ursodeoxycholic acid An epimer of chenodeoxycholic acid. It is a mammalian bile acid found first in the bear and is apparently either a precursor or a product of chenodeoxycholate. Its administration changes the composition of bile and may dissolve gallstones. It is used as a cholagogue and choleretic. Primary Biliary Cholangitis (to manage intrahepatic cholestasis)

Prevention

• Water:
  • Regularly monitor common sources involved in the transmission, especially drinking water.
  • Consume filtered water.
  • Avoid ingestion of recreational water (e.g., swimming pools).
• Good hygiene practices 
• Wear gloves while handling soiled diapers in daycare/hospital settings.
• Infected patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship should be counseled to prevent the spread of disease:
  • Avoid recreational water until 2 weeks after resolution of symptoms.
  • Perform excellent handwashing. (Note: Alcohol-based sanitizers are not effective against Cryptosporidium Cryptosporidium A genus of coccidian parasites of the family cryptosporidiidae, found in the intestinal epithelium of many vertebrates including humans. Hyper-IgM Syndrome.)
• At-risk populations should limit Limit A value (e.g., pressure or time) that should not be exceeded and which is specified by the operator to protect the lung Invasive Mechanical Ventilation exposure by avoiding contact with public or common sources of transmission.

Differential Diagnosis

• Giardiasis Giardiasis An infection of the small intestine caused by the flagellated protozoan giardia. It is spread via contaminated food and water and by direct person-to-person contact. Giardia/Giardiasis: diarrheal disease caused by the protozoan Giardia Giardia A genus of flagellate intestinal eukaryotes parasitic in various vertebrates, including humans. Characteristics include the presence of four pairs of flagella arising from a complicated system of axonemes and cysts that are ellipsoidal to ovoidal in shape. Nitroimidazoles lamblia. The spectrum of disease ranges from asymptomatic to severe diarrhea Diarrhea Diarrhea is defined as ≥ 3 watery or loose stools in a 24-hour period. There are a multitude of etiologies, which can be classified based on the underlying mechanism of disease. The duration of symptoms (acute or chronic) and characteristics of the stools (e.g., watery, bloody, steatorrheic, mucoid) can help guide further diagnostic evaluation. Diarrhea and malabsorption Malabsorption General term for a group of malnutrition syndromes caused by failure of normal intestinal absorption of nutrients. Malabsorption and Maldigestion. Most patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship present with diarrhea Diarrhea Diarrhea is defined as ≥ 3 watery or loose stools in a 24-hour period. There are a multitude of etiologies, which can be classified based on the underlying mechanism of disease. The duration of symptoms (acute or chronic) and characteristics of the stools (e.g., watery, bloody, steatorrheic, mucoid) can help guide further diagnostic evaluation. Diarrhea, bloating Bloating Constipation, abdominal pain Abdominal Pain Acute Abdomen, nausea Nausea An unpleasant sensation in the stomach usually accompanied by the urge to vomit. Common causes are early pregnancy, sea and motion sickness, emotional stress, intense pain, food poisoning, and various enteroviruses. Antiemetics, vomiting Vomiting The forcible expulsion of the contents of the stomach through the mouth. Hypokalemia, and foul-smelling steatorrhea Steatorrhea A condition that is characterized by chronic fatty diarrhea, a result of abnormal digestion and/or intestinal absorption of fats. Diarrhea. Diagnosed by DFA and stool microscopy Stool Microscopy Giardia/Giardiasis. Management includes supportive and antimicrobial therapy.
• Rotavirus Rotavirus A genus of Reoviridae, causing acute gastroenteritis in birds and mammals, including humans. Transmission is horizontal and by environmental contamination. Seven species (rotaviruses A through G) are recognized. Rotavirus enteritis Enteritis Inflammation of any segment of the small intestine. Lactose Intolerance: common cause of diarrhea Diarrhea Diarrhea is defined as ≥ 3 watery or loose stools in a 24-hour period. There are a multitude of etiologies, which can be classified based on the underlying mechanism of disease. The duration of symptoms (acute or chronic) and characteristics of the stools (e.g., watery, bloody, steatorrheic, mucoid) can help guide further diagnostic evaluation. Diarrhea in the pediatric population. Rotavirus Rotavirus A genus of Reoviridae, causing acute gastroenteritis in birds and mammals, including humans. Transmission is horizontal and by environmental contamination. Seven species (rotaviruses A through G) are recognized. Rotavirus enteritis Enteritis Inflammation of any segment of the small intestine. Lactose Intolerance presents with vomiting Vomiting The forcible expulsion of the contents of the stomach through the mouth. Hypokalemia, fever Fever Fever is defined as a measured body temperature of at least 38°C (100.4°F). Fever is caused by circulating endogenous and/or exogenous pyrogens that increase levels of prostaglandin E2 in the hypothalamus. Fever is commonly associated with chills, rigors, sweating, and flushing of the skin. Fever, and watery diarrhea Watery diarrhea Rotavirus. Diagnosed by immune-based assays and PCR PCR Polymerase chain reaction (PCR) is a technique that amplifies DNA fragments exponentially for analysis. The process is highly specific, allowing for the targeting of specific genomic sequences, even with minuscule sample amounts. The PCR cycles multiple times through 3 phases: denaturation of the template DNA, annealing of a specific primer to the individual DNA strands, and synthesis/elongation of new DNA molecules. Polymerase Chain Reaction (PCR). Management is primarily supportive, which may include IV fluids IV fluids Intravenous fluids are one of the most common interventions administered in medicine to approximate physiologic bodily fluids. Intravenous fluids are divided into 2 categories: crystalloid and colloid solutions. Intravenous fluids have a wide variety of indications, including intravascular volume expansion, electrolyte manipulation, and maintenance fluids. Intravenous Fluids in cases of severe dehydration Severe Dehydration Fluid Replacement Therapy in Children.
• Microsporidiosis Microsporidiosis Microsporidia are a group of obligate intracellular organisms that were recently reclassified as fungi. The most common species of Microsporidia is Enterocytozoon bieneusi. Microsporidia species are ubiquitous, with a wide range of reservoirs. Immunocompromised individuals (particularly those with AIDS and a CD4 count < 100 cells/µL) most commonly develop symptomatic microsporidiosis. Microsporidia/Microsporidiosis: Microsporidia Microsporidia Microsporidia are a group of obligate intracellular organisms that were recently reclassified as fungi. The most common species of Microsporidia is Enterocytozoon bieneusi. Microsporidia species are ubiquitous, with a wide range of reservoirs. Immunocompromised individuals (particularly those with AIDS and a CD4 count < 100 cells/µL) most commonly develop symptomatic microsporidiosis. Microsporidia/Microsporidiosis are obligate intracellular organisms (recently reclassified as fungi Fungi A kingdom of eukaryotic, heterotrophic organisms that live parasitically as saprobes, including mushrooms; yeasts; smuts, molds, etc. They reproduce either sexually or asexually, and have life cycles that range from simple to complex. Filamentous fungi, commonly known as molds, refer to those that grow as multicellular colonies. Mycology) that mainly infect immunocompromised immunocompromised A human or animal whose immunologic mechanism is deficient because of an immunodeficiency disorder or other disease or as the result of the administration of immunosuppressive drugs or radiation. Gastroenteritis individuals. Microsporidiosis Microsporidiosis Microsporidia are a group of obligate intracellular organisms that were recently reclassified as fungi. The most common species of Microsporidia is Enterocytozoon bieneusi. Microsporidia species are ubiquitous, with a wide range of reservoirs. Immunocompromised individuals (particularly those with AIDS and a CD4 count < 100 cells/µL) most commonly develop symptomatic microsporidiosis. Microsporidia/Microsporidiosis presents clinically with watery diarrhea Watery diarrhea Rotavirus, abdominal pain Abdominal Pain Acute Abdomen, fever Fever Fever is defined as a measured body temperature of at least 38°C (100.4°F). Fever is caused by circulating endogenous and/or exogenous pyrogens that increase levels of prostaglandin E2 in the hypothalamus. Fever is commonly associated with chills, rigors, sweating, and flushing of the skin. Fever, and eye inflammation Inflammation Inflammation is a complex set of responses to infection and injury involving leukocytes as the principal cellular mediators in the body’s defense against pathogenic organisms. Inflammation is also seen as a response to tissue injury in the process of wound healing. The 5 cardinal signs of inflammation are pain, heat, redness, swelling, and loss of function. Inflammation. Symptoms may become chronic and lead to malabsorption Malabsorption General term for a group of malnutrition syndromes caused by failure of normal intestinal absorption of nutrients. Malabsorption and Maldigestion and wasting. Diagnosis is confirmed by microscopic examination of collected stool samples. The disorder is managed by administration of antifungal Antifungal Azoles agents such as albendazole Albendazole A benzimidazole broad-spectrum anthelmintic structurally related to mebendazole that is effective against many diseases. Anthelmintic Drugs.
• Cyclosporiasis Cyclosporiasis Cyclospora is a genus within the Coccidia subclass of protozoans. They are single-celled, obligate intracellular parasites that cause intestinal infections in humans. Humans are the only host for these species, and they are both transmitted through the fecal-oral route. The symptoms of cyclosporiasis are watery diarrhea, abdominal pain, and fever. Cystoisospora/Cystoisosporiasis and Cyclospora/Cyclosporiasis: infection caused by Cyclospora cayetanensis Cyclospora Cayetanensis Cystoisospora/Cystoisosporiasis and Cyclospora/Cyclosporiasis, an obligate intracellular protozoan that causes GI disease. The disease causes watery diarrhea Watery diarrhea Rotavirus, which can last weeks to months if untreated. Diagnosis is made by identifying oocysts in stool samples. Treatment includes antimicrobial therapy, such as trimethoprim-sulfamethoxazole.
• Travelers’ diarrhea Diarrhea Diarrhea is defined as ≥ 3 watery or loose stools in a 24-hour period. There are a multitude of etiologies, which can be classified based on the underlying mechanism of disease. The duration of symptoms (acute or chronic) and characteristics of the stools (e.g., watery, bloody, steatorrheic, mucoid) can help guide further diagnostic evaluation. Diarrhea: gastroenteritis Gastroenteritis Gastroenteritis is inflammation of the stomach and intestines, commonly caused by infections from bacteria, viruses, or parasites. Transmission may be foodborne, fecal-oral, or through animal contact. Common clinical features include abdominal pain, diarrhea, vomiting, fever, and dehydration. Gastroenteritis usually caused by bacteria Bacteria Bacteria are prokaryotic single-celled microorganisms that are metabolically active and divide by binary fission. Some of these organisms play a significant role in the pathogenesis of diseases. Bacteriology, viruses Viruses Minute infectious agents whose genomes are composed of DNA or RNA, but not both. They are characterized by a lack of independent metabolism and the inability to replicate outside living host cells. Virology, or parasites in the local water, such as enterotoxigenic Escherichia coli Escherichia coli The gram-negative bacterium Escherichia coli is a key component of the human gut microbiota. Most strains of E. coli are avirulent, but occasionally they escape the GI tract, infecting the urinary tract and other sites. Less common strains of E. coli are able to cause disease within the GI tract, most commonly presenting as abdominal pain and diarrhea. Escherichia coli (ETEC), Campylobacter Campylobacter Campylobacter (“curved bacteria”) is a genus of thermophilic, S-shaped, gram-negative bacilli. There are many species of Campylobacter, with C. jejuni and C. coli most commonly implicated in human disease. Campylobacter, or norovirus Norovirus Norovirus is a nonenveloped, single-stranded, positive-sense RNA virus belonging to the Caliciviridae family. Norovirus infections are transmitted via the fecal-oral route or by aerosols from vomiting. The virus is one of the most common causes of nonbacterial gastroenteritis epidemic worldwide. Symptoms include watery and nonbloody diarrhea, nausea, vomiting, and low-grade fever. Norovirus. (Note: Cryptosporidium Cryptosporidium A genus of coccidian parasites of the family cryptosporidiidae, found in the intestinal epithelium of many vertebrates including humans. Hyper-IgM Syndrome may also cause travelers diarrhea Diarrhea Diarrhea is defined as ≥ 3 watery or loose stools in a 24-hour period. There are a multitude of etiologies, which can be classified based on the underlying mechanism of disease. The duration of symptoms (acute or chronic) and characteristics of the stools (e.g., watery, bloody, steatorrheic, mucoid) can help guide further diagnostic evaluation. Diarrhea.) Symptoms occur after consumption of contaminated water or food and include watery diarrhea Watery diarrhea Rotavirus, malaise Malaise Tick-borne Encephalitis Virus, and abdominal cramping Abdominal cramping Norovirus. The diagnosis is clinical, and the illness is self-limited.
• Celiac disease Celiac disease Celiac disease (also known as celiac sprue or gluten enteropathy) is an autoimmune reaction to gliadin, which is a component of gluten. Celiac disease is closely associated with HLA-DQ2 and HLA-DQ8. The immune response is localized to the proximal small intestine and causes the characteristic histologic findings of villous atrophy, crypt hyperplasia, and intraepithelial lymphocytosis. Celiac Disease: immunologically mediated disease resulting in mucosal inflammation Inflammation Inflammation is a complex set of responses to infection and injury involving leukocytes as the principal cellular mediators in the body’s defense against pathogenic organisms. Inflammation is also seen as a response to tissue injury in the process of wound healing. The 5 cardinal signs of inflammation are pain, heat, redness, swelling, and loss of function. Inflammation and villous atrophy Villous Atrophy Giardia/Giardiasis in the small bowel Small bowel The small intestine is the longest part of the GI tract, extending from the pyloric orifice of the stomach to the ileocecal junction. The small intestine is the major organ responsible for chemical digestion and absorption of nutrients. It is divided into 3 segments: the duodenum, the jejunum, and the ileum. Small Intestine: Anatomy; caused by ingesting gluten Gluten Prolamins in the endosperm of seeds from the triticeae tribe which includes species of wheat; barley; and rye. Celiac Disease. Symptoms include abdominal bloating Bloating Constipation and foul-smelling diarrhea Diarrhea Diarrhea is defined as ≥ 3 watery or loose stools in a 24-hour period. There are a multitude of etiologies, which can be classified based on the underlying mechanism of disease. The duration of symptoms (acute or chronic) and characteristics of the stools (e.g., watery, bloody, steatorrheic, mucoid) can help guide further diagnostic evaluation. Diarrhea. Patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship may also have nutritional deficiencies and weight loss Weight loss Decrease in existing body weight. Bariatric Surgery due to malabsorption Malabsorption General term for a group of malnutrition syndromes caused by failure of normal intestinal absorption of nutrients. Malabsorption and Maldigestion. The diagnosis is established with serologic markers and a small bowel Small bowel The small intestine is the longest part of the GI tract, extending from the pyloric orifice of the stomach to the ileocecal junction. The small intestine is the major organ responsible for chemical digestion and absorption of nutrients. It is divided into 3 segments: the duodenum, the jejunum, and the ileum. Small Intestine: Anatomy biopsy Biopsy Removal and pathologic examination of specimens from the living body. Ewing Sarcoma. Management requires a strict, gluten-free diet.
• Inflammatory bowel disease: includes Crohn’s disease and ulcerative colitis Colitis Inflammation of the colon section of the large intestine, usually with symptoms such as diarrhea (often with blood and mucus), abdominal pain, and fever. Pseudomembranous Colitis. Inflammatory bowel disease is characterized by chronic inflammation Chronic Inflammation Inflammation of the GI tract due to a cell-mediated immune response to the GI mucosa. Symptoms include diarrhea Diarrhea Diarrhea is defined as ≥ 3 watery or loose stools in a 24-hour period. There are a multitude of etiologies, which can be classified based on the underlying mechanism of disease. The duration of symptoms (acute or chronic) and characteristics of the stools (e.g., watery, bloody, steatorrheic, mucoid) can help guide further diagnostic evaluation. Diarrhea, abdominal pain Abdominal Pain Acute Abdomen, weight loss Weight loss Decrease in existing body weight. Bariatric Surgery, and extraintestinal manifestations. Diagnosis is with imaging, endoscopy Endoscopy Procedures of applying endoscopes for disease diagnosis and treatment. Endoscopy involves passing an optical instrument through a small incision in the skin i.e., percutaneous; or through a natural orifice and along natural body pathways such as the digestive tract; and/or through an incision in the wall of a tubular structure or organ, i.e. Transluminal, to examine or perform surgery on the interior parts of the body. Gastroesophageal Reflux Disease (GERD), and biopsy Biopsy Removal and pathologic examination of specimens from the living body. Ewing Sarcoma. Management involves steroids Steroids A group of polycyclic compounds closely related biochemically to terpenes. They include cholesterol, numerous hormones, precursors of certain vitamins, bile acids, alcohols (sterols), and certain natural drugs and poisons. Steroids have a common nucleus, a fused, reduced 17-carbon atom ring system, cyclopentanoperhydrophenanthrene. Most steroids also have two methyl groups and an aliphatic side-chain attached to the nucleus. Benign Liver Tumors, aminosalicylates, immunomodulators, and biologic agents Biologic Agents Immunosuppressants.
• Lactose intolerance Lactose intolerance Lactose intolerance (LI) describes a constellation of symptoms due to lactase deficiency (LD), the enzyme located in the brush border of the absorptive cells in the small intestine. Lactose is the disaccharide present in milk and requires hydrolysis by lactase to break it down into its 2 absorbable constituents, glucose and galactose. Lactose intolerance typically presents with bloating, abdominal cramping, diarrhea, and flatulence. Lactose Intolerance: intolerance to lactose-containing foods due to lactase deficiency Lactase deficiency Lactose Intolerance. Symptoms include crampy abdominal pain Abdominal Pain Acute Abdomen, bloating Bloating Constipation, nausea Nausea An unpleasant sensation in the stomach usually accompanied by the urge to vomit. Common causes are early pregnancy, sea and motion sickness, emotional stress, intense pain, food poisoning, and various enteroviruses. Antiemetics, and diarrhea Diarrhea Diarrhea is defined as ≥ 3 watery or loose stools in a 24-hour period. There are a multitude of etiologies, which can be classified based on the underlying mechanism of disease. The duration of symptoms (acute or chronic) and characteristics of the stools (e.g., watery, bloody, steatorrheic, mucoid) can help guide further diagnostic evaluation. Diarrhea after ingesting lactose. Diagnosis is based on the association with lactose-containing foods and a lactose hydrogen breath test Hydrogen breath test Lactose Intolerance. Management includes restriction of dietary lactose and enzyme replacement Enzyme replacement Therapeutic replacement or supplementation of defective or missing enzymes to alleviate the effects of enzyme deficiency (e.g., glucosylceramidase replacement for gaucher disease). Severe Combined Immunodeficiency (SCID).