Hepatic Encephalopathy (Clinical)

Epidemiology and Etiology

Epidemiology^[4,5,10]

• Affects:
  • 30%–45% of patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship with cirrhosis Cirrhosis Cirrhosis is a late stage of hepatic parenchymal necrosis and scarring (fibrosis) most commonly due to hepatitis C infection and alcoholic liver disease. Patients may present with jaundice, ascites, and hepatosplenomegaly. Cirrhosis can also cause complications such as hepatic encephalopathy, portal hypertension, portal vein thrombosis, and hepatorenal syndrome. Cirrhosis
  • 10%–50% of patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship who undergo transjugular intrahepatic portosystemic shunts (TIPS)
• 2nd-most common cause of hospitalization Hospitalization The confinement of a patient in a hospital. Delirium for cirrhotic patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship (behind ascites Ascites Ascites is the pathologic accumulation of fluid within the peritoneal cavity that occurs due to an osmotic and/or hydrostatic pressure imbalance secondary to portal hypertension (cirrhosis, heart failure) or non-portal hypertension (hypoalbuminemia, malignancy, infection). Ascites)

Etiology^[4,10]

Hepatic encephalopathy Encephalopathy Hyper-IgM Syndrome (HE) is seen in patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship with severe 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 disease or liver failure Liver 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, and can be exacerbated by:

• Decreased metabolism or clearance of ammonia Ammonia A colorless alkaline gas. It is formed in the body during decomposition of organic materials during a large number of metabolically important reactions. Note that the aqueous form of ammonia is referred to as ammonium hydroxide. Acid-Base Balance
  • Renal failure Renal failure Conditions in which the kidneys perform below the normal level in the ability to remove wastes, concentrate urine, and maintain electrolyte balance; blood pressure; and calcium metabolism. Renal insufficiency can be classified by the degree of kidney damage (as measured by the level of proteinuria) and reduction in glomerular filtration rate. Crush Syndrome
  • Diuretics Diuretics Agents that promote the excretion of urine through their effects on kidney function. Heart Failure and Angina Medication
  • Transjugular intrahepatic portosystemic shunt Transjugular intrahepatic portosystemic shunt A type of surgical portosystemic shunt to reduce portal hypertension with associated complications of esophageal varices and ascites. It is performed percutaneously through the jugular vein and involves the creation of an intrahepatic shunt between the hepatic vein and portal vein. The channel is maintained by a metallic stent. The procedure can be performed in patients who have failed sclerotherapy and is an additional option to the surgical techniques of portocaval, mesocaval, and splenorenal shunts. It takes one to three hours to perform. Ascites (TIPS)
• Increased production or 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 of ammonia Ammonia A colorless alkaline gas. It is formed in the body during decomposition of organic materials during a large number of metabolically important reactions. Note that the aqueous form of ammonia is referred to as ammonium hydroxide. Acid-Base Balance
  • Excess dietary protein intake
  • Gastrointestinal (GI) bleed
  • Constipation Constipation Constipation is common and may be due to a variety of causes. Constipation is generally defined as bowel movement frequency < 3 times per week. Patients who are constipated often strain to pass hard stools. The condition is classified as primary (also known as idiopathic or functional constipation) or secondary, and as acute or chronic. Constipation
  • Infection ( spontaneous bacterial peritonitis Spontaneous Bacterial Peritonitis Ascites)
• Electrolyte disturbances
  • Hypokalemia Hypokalemia Hypokalemia is defined as plasma potassium (K+) concentration < 3.5 mEq/L. Homeostatic mechanisms maintain plasma concentration between 3.5-5.2 mEq/L despite marked variation in dietary intake. Hypokalemia can be due to renal losses, GI losses, transcellular shifts, or poor dietary intake. Hypokalemia
  • Metabolic alkalosis Alkalosis A pathological condition that removes acid or adds base to the body fluids. Respiratory Alkalosis
• Respiratory issues
  • Hypoxia Hypoxia Sub-optimal oxygen levels in the ambient air of living organisms. Ischemic Cell Damage
  • Hypercapnia Hypercapnia A clinical manifestation of abnormal increase in the amount of carbon dioxide in arterial blood. Neonatal Respiratory Distress Syndrome
• Vascular occlusion
  • Portal vein Portal vein A short thick vein formed by union of the superior mesenteric vein and the splenic vein. Liver: Anatomy thrombosis Thrombosis Formation and development of a thrombus or blood clot in the blood vessel. Epidemic Typhus
  • Hepatic vein Hepatic vein Veins which drain the liver. Budd-Chiari Syndrome thrombosis Thrombosis Formation and development of a thrombus or blood clot in the blood vessel. Epidemic Typhus
• Drugs
  • Opiates Opiates Opiates are drugs that are derived from the sap of the opium poppy. Opiates have been used since antiquity for the relief of acute severe pain. Opioids are synthetic opiates with properties that are substantially similar to those of opiates. Opioid Analgesics
  • Benzodiazepines Benzodiazepines Benzodiazepines work on the gamma-aminobutyric acid type A (GABAA) receptor to produce inhibitory effects on the CNS. Benzodiazepines do not mimic GABA, the main inhibitory neurotransmitter in humans, but instead potentiate GABA activity. Benzodiazepines
  • Alcohol
  • Hypnotics

Mnemonic

Precipitating factors for hepatic encephalopathy Encephalopathy Hyper-IgM Syndrome can be remembered by the mnemonic “HEPATICS”:

• Hemorrhage in the GI tract
• Excess dietary protein
• Potassium ( hypokalemia Hypokalemia Hypokalemia is defined as plasma potassium (K+) concentration < 3.5 mEq/L. Homeostatic mechanisms maintain plasma concentration between 3.5-5.2 mEq/L despite marked variation in dietary intake. Hypokalemia can be due to renal losses, GI losses, transcellular shifts, or poor dietary intake. Hypokalemia)
• Alkalosis or azotemia Azotemia A biochemical abnormality referring to an elevation of blood urea nitrogen and creatinine. Azotemia can be produced by kidney diseases or other extrarenal disorders. When azotemia becomes associated with a constellation of clinical signs, it is termed uremia. Acute Kidney Injury
• TIPS procedure
• Infection
• Constipation
• Sedatives

Pathophysiology

Normal physiology:^[2,10]

• The GI tract is the primary source of ammonia Ammonia A colorless alkaline gas. It is formed in the body during decomposition of organic materials during a large number of metabolically important reactions. Note that the aqueous form of ammonia is referred to as ammonium hydroxide. Acid-Base Balance, where it is produced by:
  • Enterocytes from glutamine Glutamine A non-essential amino acid present abundantly throughout the body and is involved in many metabolic processes. It is synthesized from glutamic acid and ammonia. It is the principal carrier of nitrogen in the body and is an important energy source for many cells. Synthesis of Nonessential Amino Acids
  • Catabolism of nitrogen Nitrogen An element with the atomic symbol n, atomic number 7, and atomic weight [14. 00643; 14. 00728]. Nitrogen exists as a diatomic gas and makes up about 78% of the earth’s atmosphere by volume. It is a constituent of proteins and nucleic acids and found in all living cells. Urea Cycle by colonic 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
• Ammonia Ammonia A colorless alkaline gas. It is formed in the body during decomposition of organic materials during a large number of metabolically important reactions. Note that the aqueous form of ammonia is referred to as ammonium hydroxide. Acid-Base Balance enters the circulation Circulation The movement of the blood as it is pumped through the cardiovascular system. ABCDE Assessment via the portal vein Portal vein A short thick vein formed by union of the superior mesenteric vein and the splenic vein. Liver: Anatomy.
• 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 clears this ammonia Ammonia A colorless alkaline gas. It is formed in the body during decomposition of organic materials during a large number of metabolically important reactions. Note that the aqueous form of ammonia is referred to as ammonium hydroxide. Acid-Base Balance by converting it into glutamine Glutamine A non-essential amino acid present abundantly throughout the body and is involved in many metabolic processes. It is synthesized from glutamic acid and ammonia. It is the principal carrier of nitrogen in the body and is an important energy source for many cells. Synthesis of Nonessential Amino Acids → prevents entry into the systemic circulation Circulation The movement of the blood as it is pumped through the cardiovascular system. ABCDE Assessment

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 disease allows disruption of normal ammonia Ammonia A colorless alkaline gas. It is formed in the body during decomposition of organic materials during a large number of metabolically important reactions. Note that the aqueous form of ammonia is referred to as ammonium hydroxide. Acid-Base Balance regulation through:^[2,4,10]

• Hepatocyte dysfunction: ↓ conversion of ammonia Ammonia A colorless alkaline gas. It is formed in the body during decomposition of organic materials during a large number of metabolically important reactions. Note that the aqueous form of ammonia is referred to as ammonium hydroxide. Acid-Base Balance to glutamine Glutamine A non-essential amino acid present abundantly throughout the body and is involved in many metabolic processes. It is synthesized from glutamic acid and ammonia. It is the principal carrier of nitrogen in the body and is an important energy source for many cells. Synthesis of Nonessential Amino Acids → ↑ serum ammonia Ammonia A colorless alkaline gas. It is formed in the body during decomposition of organic materials during a large number of metabolically important reactions. Note that the aqueous form of ammonia is referred to as ammonium hydroxide. Acid-Base Balance
• Splanchnic and peripheral vasodilation Vasodilation The physiological widening of blood vessels by relaxing the underlying vascular smooth muscle. Pulmonary Hypertension Drugs: portosystemic shunting away from the 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 → ↑ serum ammonia Ammonia A colorless alkaline gas. It is formed in the body during decomposition of organic materials during a large number of metabolically important reactions. Note that the aqueous form of ammonia is referred to as ammonium hydroxide. Acid-Base Balance
• ↑ Blood-brain barrier Blood-brain barrier Specialized non-fenestrated tightly-joined endothelial cells with tight junctions that form a transport barrier for certain substances between the cerebral capillaries and the brain tissue. Systemic and Special Circulations permeability: allows ↑ delivery of ammonia Ammonia A colorless alkaline gas. It is formed in the body during decomposition of organic materials during a large number of metabolically important reactions. Note that the aqueous form of ammonia is referred to as ammonium hydroxide. Acid-Base Balance to astrocytes Astrocytes A class of large neuroglial (macroglial) cells in the central nervous system – the largest and most numerous neuroglial cells in the brain and spinal cord. Astrocytes (from ‘star’ cells) are irregularly shaped with many long processes, including those with ‘end feet’ which form the glial (limiting) membrane and directly and indirectly contribute to the blood-brain barrier. They regulate the extracellular ionic and chemical environment, and ‘reactive astrocytes’ (along with microglia) respond to injury. Nervous System: Histology

Impaired brain Brain The part of central nervous system that is contained within the skull (cranium). Arising from the neural tube, the embryonic brain is comprised of three major parts including prosencephalon (the forebrain); mesencephalon (the midbrain); and rhombencephalon (the hindbrain). The developed brain consists of cerebrum; cerebellum; and other structures in the brain stem. Nervous System: Anatomy, Structure, and Classification function results from a buildup of ammonia Ammonia A colorless alkaline gas. It is formed in the body during decomposition of organic materials during a large number of metabolically important reactions. Note that the aqueous form of ammonia is referred to as ammonium hydroxide. Acid-Base Balance, where it:^[2,4]

• Is utilized to produce glutamine Glutamine A non-essential amino acid present abundantly throughout the body and is involved in many metabolic processes. It is synthesized from glutamic acid and ammonia. It is the principal carrier of nitrogen in the body and is an important energy source for many cells. Synthesis of Nonessential Amino Acids → ↑ osmotic pressure Osmotic pressure The pressure required to prevent the passage of solvent through a semipermeable membrane that separates a pure solvent from a solution of the solvent and solute or that separates different concentrations of a solution. It is proportional to the osmolality of the solution. Intravenous Fluids and swelling Swelling Inflammation of astrocytes Astrocytes A class of large neuroglial (macroglial) cells in the central nervous system – the largest and most numerous neuroglial cells in the brain and spinal cord. Astrocytes (from ‘star’ cells) are irregularly shaped with many long processes, including those with ‘end feet’ which form the glial (limiting) membrane and directly and indirectly contribute to the blood-brain barrier. They regulate the extracellular ionic and chemical environment, and ‘reactive astrocytes’ (along with microglia) respond to injury. Nervous System: Histology → cerebral edema Cerebral edema Increased intracellular or extracellular fluid in brain tissue. Cytotoxic brain edema (swelling due to increased intracellular fluid) is indicative of a disturbance in cell metabolism, and is commonly associated with hypoxic or ischemic injuries. An increase in extracellular fluid may be caused by increased brain capillary permeability (vasogenic edema), an osmotic gradient, local blockages in interstitial fluid pathways, or by obstruction of CSF flow (e.g., obstructive hydrocephalus). Increased Intracranial Pressure (ICP)
• Binds to γ-aminobutyric acid ( GABA GABA The most common inhibitory neurotransmitter in the central nervous system. Receptors and Neurotransmitters of the CNS) receptors Receptors Receptors are proteins located either on the surface of or within a cell that can bind to signaling molecules known as ligands (e.g., hormones) and cause some type of response within the cell. Receptors → ↑ GABA-energic inhibitory function
• Inhibits a step in the Krebs cycle Krebs cycle The citric acid cycle, also known as the tricarboxylic acid (TCA) cycle or the krebs cycle, is a cyclic set of reactions that occurs in the mitochondrial matrix. The TCA cycle is the continuation of any metabolic pathway that produces pyruvate, which is converted into its main substrate, acetyl-CoA. Citric Acid Cycle → ↓ metabolic fuel supply

Clinical Presentation

Symptoms^[1,9]

• Cognitive impairment (including mental slowing, confusion, somnolence, and coma Coma Coma is defined as a deep state of unarousable unresponsiveness, characterized by a score of 3 points on the GCS. A comatose state can be caused by a multitude of conditions, making the precise epidemiology and prognosis of coma difficult to determine. Coma)
• Sleep-pattern disturbances
  • Insomnia Insomnia Insomnia is a sleep disorder characterized by difficulty in the initiation, maintenance, and consolidation of sleep, leading to impairment of function. Patients may exhibit symptoms such as difficulty falling asleep, disrupted sleep, trouble going back to sleep, early awakenings, and feeling tired upon waking. Insomnia
  • Hypersomnia Hypersomnia Disorders characterized by hypersomnolence during normal waking hours that may impair cognitive functioning. Subtypes include primary hypersomnia disorders (e.g., idiopathic hypersomnolence; narcolepsy; and kleine-levin syndrome) and secondary hypersomnia disorders where excessive somnolence can be attributed to a known cause (e.g., drug affect, mental disorders, and sleep apnea syndrome). Whipple’s Disease
  • Usually precedes other mental status changes
• Mood changes
  • Euphoria Euphoria An exaggerated feeling of physical and emotional well-being not consonant with apparent stimuli or events; usually of psychologic origin, but also seen in organic brain disease and toxic states. Hepatic Encephalopathy
  • Depression

Physical exam findings^[5,7]

• Asterixis Asterixis Hepatic Encephalopathy (flapping of outstretched and dorsiflexed hands)
• Ataxia Ataxia Impairment of the ability to perform smoothly coordinated voluntary movements. This condition may affect the limbs, trunk, eyes, pharynx, larynx, and other structures. Ataxia may result from impaired sensory or motor function. Sensory ataxia may result from posterior column injury or peripheral nerve diseases. Motor ataxia may be associated with cerebellar diseases; cerebral cortex diseases; thalamic diseases; basal ganglia diseases; injury to the red nucleus; and other conditions. Ataxia-telangiectasia
• Hyperreflexia
• Nystagmus Nystagmus Involuntary movements of the eye that are divided into two types, jerk and pendular. Jerk nystagmus has a slow phase in one direction followed by a corrective fast phase in the opposite direction, and is usually caused by central or peripheral vestibular dysfunction. Pendular nystagmus features oscillations that are of equal velocity in both directions and this condition is often associated with visual loss early in life. Albinism
• Bradykinesia Bradykinesia Parkinson’s Disease
• Hypokinesia
• Slow monotonous speech
• Parkinsonian-like tremor Tremor Cyclical movement of a body part that can represent either a physiologic process or a manifestation of disease. Intention or action tremor, a common manifestation of cerebellar diseases, is aggravated by movement. In contrast, resting tremor is maximal when there is no attempt at voluntary movement, and occurs as a relatively frequent manifestation of parkinson disease. Myotonic Dystrophies
• Clonus Clonus Ehrlichiosis and Anaplasmosis
• Evidence of chronic 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 disease:
  • Jaundice Jaundice Jaundice is the abnormal yellowing of the skin and/or sclera caused by the accumulation of bilirubin. Hyperbilirubinemia is caused by either an increase in bilirubin production or a decrease in the hepatic uptake, conjugation, or excretion of bilirubin. Jaundice
  • Ascites Ascites Ascites is the pathologic accumulation of fluid within the peritoneal cavity that occurs due to an osmotic and/or hydrostatic pressure imbalance secondary to portal hypertension (cirrhosis, heart failure) or non-portal hypertension (hypoalbuminemia, malignancy, infection). Ascites
  • Peripheral edema Peripheral edema Peripheral edema is the swelling of the lower extremities, namely, legs, feet, and ankles. Edema
  • Palmar erythema Palmar Erythema Cirrhosis
  • Spider angiomata Spider Angiomata Portal Hypertension
  • Hepatomegaly

Severity^[5,6]

The West Haven  (WHC) criteria are used to grade the clinical severity.

Classification^[5,7]

HE is classified according to the underlying disease, severity of manifestations, time course, and precipitants.

• Underlying disease:
  • Type A: results from acute liver failure Liver 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
  • Type B: results from portosystemic bypass or shunting
  • Type C: results from cirrhosis Cirrhosis Cirrhosis is a late stage of hepatic parenchymal necrosis and scarring (fibrosis) most commonly due to hepatitis C infection and alcoholic liver disease. Patients may present with jaundice, ascites, and hepatosplenomegaly. Cirrhosis can also cause complications such as hepatic encephalopathy, portal hypertension, portal vein thrombosis, and hepatorenal syndrome. Cirrhosis
• Severity: see WHC above
• Time course:
  • Episodic
  • Recurrent: ≥ 2 HE episodes within 6 months
  • Persistent: behavioral changes always present (status not going back to baseline), with episodes of overt HE in between
• Precipitating factors:
  • Nonprecipitated
  • Precipitated (identify the causes):
    • Drugs (e.g., benzodiazepines Benzodiazepines Benzodiazepines work on the gamma-aminobutyric acid type A (GABAA) receptor to produce inhibitory effects on the CNS. Benzodiazepines do not mimic GABA, the main inhibitory neurotransmitter in humans, but instead potentiate GABA activity. Benzodiazepines, alcohol, narcotics)
    • ↑ Ammonia Ammonia A colorless alkaline gas. It is formed in the body during decomposition of organic materials during a large number of metabolically important reactions. Note that the aqueous form of ammonia is referred to as ammonium hydroxide. Acid-Base Balance (e.g., constipation Constipation Constipation is common and may be due to a variety of causes. Constipation is generally defined as bowel movement frequency < 3 times per week. Patients who are constipated often strain to pass hard stools. The condition is classified as primary (also known as idiopathic or functional constipation) or secondary, and as acute or chronic. Constipation, GI bleeding, increased protein intake, electrolyte abnormalities, metabolic alkalosis Alkalosis A pathological condition that removes acid or adds base to the body fluids. Respiratory Alkalosis)
    • Dehydration Dehydration The condition that results from excessive loss of water from a living organism. Volume Depletion and Dehydration (e.g., from paracentesis Paracentesis A procedure in which fluid is withdrawn from a body cavity or organ via a trocar and cannula, needle, or other hollow instrument. Portal Hypertension, diuretic intake, vomiting Vomiting The forcible expulsion of the contents of the stomach through the mouth. Hypokalemia, 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)
    • Portosystemic shunting
    • Vascular occlusion (e.g., hepatic or portal vein Portal vein A short thick vein formed by union of the superior mesenteric vein and the splenic vein. Liver: Anatomy thrombosis Thrombosis Formation and development of a thrombus or blood clot in the blood vessel. Epidemic Typhus)
    • Hepatocellular carcinoma Hepatocellular carcinoma Hepatocellular carcinoma (HCC) typically arises in a chronically diseased or cirrhotic liver and is the most common primary liver cancer. Diagnosis may include ultrasound, CT, MRI, biopsy (if inconclusive imaging), and/or biomarkers. Hepatocellular Carcinoma (HCC) and Liver Metastases

Diagnosis

Hepatic encephalopathy Encephalopathy Hyper-IgM Syndrome is a clinical diagnosis, and other conditions must be excluded.

Clinical findings:^[5,7]

• Mental status changes, including:
  • Sleep Sleep A readily reversible suspension of sensorimotor interaction with the environment, usually associated with recumbency and immobility. Physiology of Sleep pattern changes
  • Memory Memory Complex mental function having four distinct phases: (1) memorizing or learning, (2) retention, (3) recall, and (4) recognition. Clinically, it is usually subdivided into immediate, recent, and remote memory. Psychiatric Assessment changes
  • Decrease in attention Attention Focusing on certain aspects of current experience to the exclusion of others. It is the act of heeding or taking notice or concentrating. Psychiatric Assessment span
  • Impairment in daily activities
• Examination:
  • Assess patient (using WHC)
  • In those with altered consciousness, Glasgow Coma Scale (GCS) score is added.
  • Some findings can be subtle (psychomotor slowing, lack of attention Attention Focusing on certain aspects of current experience to the exclusion of others. It is the act of heeding or taking notice or concentrating. Psychiatric Assessment) and may be missed.
  • Asterixis Asterixis Hepatic Encephalopathy and disorientation Disorientation St. Louis Encephalitis Virus (which have good interobserver reliability Reliability Reliability refers to the reproducibility of a test or research finding. Causality, Validity, and Reliability) are markers of overt HE.
  • Other neurologic disturbances (as listed in the physical exam findings above)

Supporting evidence: ↑ serum ammonia Ammonia A colorless alkaline gas. It is formed in the body during decomposition of organic materials during a large number of metabolically important reactions. Note that the aqueous form of ammonia is referred to as ammonium hydroxide. Acid-Base Balance ( aids AIDS Chronic HIV infection and depletion of CD4 cells eventually results in acquired immunodeficiency syndrome (AIDS), which can be diagnosed by the presence of certain opportunistic diseases called AIDS-defining conditions. These conditions include a wide spectrum of bacterial, viral, fungal, and parasitic infections as well as several malignancies and generalized conditions. HIV Infection and AIDS in the evaluation, but is not diagnostic):^[7]

• Impaired 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 function ( ammonia Ammonia A colorless alkaline gas. It is formed in the body during decomposition of organic materials during a large number of metabolically important reactions. Note that the aqueous form of ammonia is referred to as ammonium hydroxide. Acid-Base Balance is not converted to urea Urea A compound formed in the liver from ammonia produced by the deamination of amino acids. It is the principal end product of protein catabolism and constitutes about one half of the total urinary solids. Urea Cycle or glutamine Glutamine A non-essential amino acid present abundantly throughout the body and is involved in many metabolic processes. It is synthesized from glutamic acid and ammonia. It is the principal carrier of nitrogen in the body and is an important energy source for many cells. Synthesis of Nonessential Amino Acids) and muscle wasting Muscle Wasting Duchenne Muscular Dystrophy contribute to ↑ ammonia Ammonia A colorless alkaline gas. It is formed in the body during decomposition of organic materials during a large number of metabolically important reactions. Note that the aqueous form of ammonia is referred to as ammonium hydroxide. Acid-Base Balance.
• Although a ↑ ammonia Ammonia A colorless alkaline gas. It is formed in the body during decomposition of organic materials during a large number of metabolically important reactions. Note that the aqueous form of ammonia is referred to as ammonium hydroxide. Acid-Base Balance level is not specific for HE and does not have prognostic value, a normal level requires reevaluation of the diagnosis.
• Levels can increase with:
  • Tourniquet use
  • Fist clenching
  • Other nonhepatic conditions (e.g., smoking Smoking Willful or deliberate act of inhaling and exhaling smoke from burning substances or agents held by hand. Interstitial Lung Diseases, 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, shock Shock Shock is a life-threatening condition associated with impaired circulation that results in tissue hypoxia. The different types of shock are based on the underlying cause: distributive (↑ cardiac output (CO), ↓ systemic vascular resistance (SVR)), cardiogenic (↓ CO, ↑ SVR), hypovolemic (↓ CO, ↑ SVR), obstructive (↓ CO), and mixed. Types of Shock, renal disease)

Evaluate for precipitants and alternative diagnoses:

• Laboratory:
  • 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 → hypoglycemia Hypoglycemia Hypoglycemia is an emergency condition defined as a serum glucose level ≤ 70 mg/dL (≤ 3.9 mmol/L) in diabetic patients. In nondiabetic patients, there is no specific or defined limit for normal serum glucose levels, and hypoglycemia is defined mainly by its clinical features. Hypoglycemia or hyperglycemia Hyperglycemia Abnormally high blood glucose level. Diabetes Mellitus
  • Basic metabolic panel Basic Metabolic Panel Primary vs Secondary Headaches → hypokalemia Hypokalemia Hypokalemia is defined as plasma potassium (K+) concentration < 3.5 mEq/L. Homeostatic mechanisms maintain plasma concentration between 3.5-5.2 mEq/L despite marked variation in dietary intake. Hypokalemia can be due to renal losses, GI losses, transcellular shifts, or poor dietary intake. Hypokalemia, alkalosis Alkalosis A pathological condition that removes acid or adds base to the body fluids. Respiratory Alkalosis, renal failure Renal failure Conditions in which the kidneys perform below the normal level in the ability to remove wastes, concentrate urine, and maintain electrolyte balance; blood pressure; and calcium metabolism. Renal insufficiency can be classified by the degree of kidney damage (as measured by the level of proteinuria) and reduction in glomerular filtration rate. Crush Syndrome
  • Complete blood count → infection, GI bleed
  • Thyroid-stimulating hormone Thyroid-stimulating hormone A glycoprotein hormone secreted by the adenohypophysis. Thyrotropin stimulates thyroid gland by increasing the iodide transport, synthesis and release of thyroid hormones (thyroxine and triiodothyronine). Thyroid Hormones → myxedema coma Myxedema Coma Hypothyroidism
  • Arterial blood gas Arterial blood gas Respiratory Alkalosis → alkalosis Alkalosis A pathological condition that removes acid or adds base to the body fluids. Respiratory Alkalosis, hypercapnia Hypercapnia A clinical manifestation of abnormal increase in the amount of carbon dioxide in arterial blood. Neonatal Respiratory Distress Syndrome
  • Drug screen 
  • Alcohol level
  • Blood cultures → infection
  • Urinalysis Urinalysis Examination of urine by chemical, physical, or microscopic means. Routine urinalysis usually includes performing chemical screening tests, determining specific gravity, observing any unusual color or odor, screening for bacteriuria, and examining the sediment microscopically. Urinary Tract Infections (UTIs) in Children → infection
• Brain Brain The part of central nervous system that is contained within the skull (cranium). Arising from the neural tube, the embryonic brain is comprised of three major parts including prosencephalon (the forebrain); mesencephalon (the midbrain); and rhombencephalon (the hindbrain). The developed brain consists of cerebrum; cerebellum; and other structures in the brain stem. Nervous System: Anatomy, Structure, and Classification imaging:^[5,7]
  • Brain Brain The part of central nervous system that is contained within the skull (cranium). Arising from the neural tube, the embryonic brain is comprised of three major parts including prosencephalon (the forebrain); mesencephalon (the midbrain); and rhombencephalon (the hindbrain). The developed brain consists of cerebrum; cerebellum; and other structures in the brain stem. Nervous System: Anatomy, Structure, and Classification computed tomography (CT) → rule out intracranial pathology
  • Brain Brain The part of central nervous system that is contained within the skull (cranium). Arising from the neural tube, the embryonic brain is comprised of three major parts including prosencephalon (the forebrain); mesencephalon (the midbrain); and rhombencephalon (the hindbrain). The developed brain consists of cerebrum; cerebellum; and other structures in the brain stem. Nervous System: Anatomy, Structure, and Classification CT is part of the workup, especially in those having a 1st episode of HE and/or when the diagnosis is uncertain.
  • Intracerebral bleeding is increased 5x in this patient population, and a brain Brain The part of central nervous system that is contained within the skull (cranium). Arising from the neural tube, the embryonic brain is comprised of three major parts including prosencephalon (the forebrain); mesencephalon (the midbrain); and rhombencephalon (the hindbrain). The developed brain consists of cerebrum; cerebellum; and other structures in the brain stem. Nervous System: Anatomy, Structure, and Classification CT is the test of choice in those in whom this condition is suspected. 
• Ultrasound (abdomen):
  • Can assist with diagnosis of portal vein Portal vein A short thick vein formed by union of the superior mesenteric vein and the splenic vein. Liver: Anatomy thrombosis Thrombosis Formation and development of a thrombus or blood clot in the blood vessel. Epidemic Typhus
  • Evaluate for ascites Ascites Ascites is the pathologic accumulation of fluid within the peritoneal cavity that occurs due to an osmotic and/or hydrostatic pressure imbalance secondary to portal hypertension (cirrhosis, heart failure) or non-portal hypertension (hypoalbuminemia, malignancy, infection). Ascites → diagnostic paracentesis Paracentesis A procedure in which fluid is withdrawn from a body cavity or organ via a trocar and cannula, needle, or other hollow instrument. Portal Hypertension → rule out spontaneous bacterial peritonitis Spontaneous Bacterial Peritonitis Ascites ( SBP SBP Ascites)
  • Recommended in those with acute hepatic decompensation without a clear etiology^[7]
• Additional tests:^[7]
  • Chest X-ray X-ray Penetrating electromagnetic radiation emitted when the inner orbital electrons of an atom are excited and release radiant energy. X-ray wavelengths range from 1 pm to 10 nm. Hard x-rays are the higher energy, shorter wavelength x-rays. Soft x-rays or grenz rays are less energetic and longer in wavelength. The short wavelength end of the x-ray spectrum overlaps the gamma rays wavelength range. The distinction between gamma rays and x-rays is based on their radiation source. Pulmonary Function Tests: perform if clinically indicated ( lung infection Lung infection Pneumonia or pulmonary inflammation is an acute or chronic inflammation of lung tissue. Causes include infection with bacteria, viruses, or fungi. In more rare cases, pneumonia can also be caused through toxic triggers through inhalation of toxic substances, immunological processes, or in the course of radiotherapy. Pneumonia can be a precipitating factor for HE)^[9]
  • Electroencephalography Electroencephalography Seizures ( EEG EEG Seizures): may aid in diagnosing HE in comatose Comatose A profound state of unconsciousness associated with depressed cerebral activity from which the individual cannot be aroused. Coma generally occurs when there is dysfunction or injury involving both cerebral hemispheres or the brain stem reticular formation. Hyponatremia patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship (shows ↓ brain-wave frequency and amplitude)
  • Lumbar puncture Lumbar Puncture Febrile Infant: if etiology of altered mental status Altered Mental Status Sepsis in Children is unclear or if other central nervous system Central nervous system The main information-processing organs of the nervous system, consisting of the brain, spinal cord, and meninges. Nervous System: Anatomy, Structure, and Classification condition is considered (normal results in HE)

Tip: Spontaneous bacterial peritonitis Spontaneous Bacterial Peritonitis Ascites should be ruled out in all patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship presenting with hepatic encephalopathy Encephalopathy Hyper-IgM Syndrome and ascites Ascites Ascites is the pathologic accumulation of fluid within the peritoneal cavity that occurs due to an osmotic and/or hydrostatic pressure imbalance secondary to portal hypertension (cirrhosis, heart failure) or non-portal hypertension (hypoalbuminemia, malignancy, infection). Ascites.

Management

Management of overt HE

Treatment focuses on identifying and treating precipitating factors, and lowering the serum ammonia Ammonia A colorless alkaline gas. It is formed in the body during decomposition of organic materials during a large number of metabolically important reactions. Note that the aqueous form of ammonia is referred to as ammonium hydroxide. Acid-Base Balance concentration.

General supportive care:

• Establish a safe environment for the patient.^[5,7,10]
  • Hospitalization Hospitalization The confinement of a patient in a hospital. Delirium for severe symptoms or impairment that prevents adherence to the prescribed treatment
  • Mild symptoms can be managed on an outpatient basis (provided caregivers are able to detect worsening signs of HE).
  • For higher grades (grades 3–4) of HE (especially in the unconscious Unconscious Those forces and content of the mind which are not ordinarily available to conscious awareness or to immediate recall. Psychotherapy patient), consider admission to an intensive care setting.
  • Those who are unable to maintain airway Airway ABCDE Assessment protection should be intubated.
  • A nasogastric tube Nasogastric tube Malnutrition in children in resource-limited countries may be utilized for oral therapies when an inability to swallow or aspiration risk is present.
• Proper hydration:
  • Dehydration Dehydration The condition that results from excessive loss of water from a living organism. Volume Depletion and Dehydration can be from ↓ fluid intake, diuretics Diuretics Agents that promote the excretion of urine through their effects on kidney function. Heart Failure and Angina Medication, GI bleeding, and lactulose-related 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.
  • Monitor:
    • Intake and output
    • Serial chemistries and hemoglobin
• Avoid sedatives.^[10]
• Treat precipitating causes.
  • Most cases of HE are precipitated by other factors.^[8,10]
  • 90% of cases treated when precipitating factors addressed^[5]
• Provide nutritional support.^[7,8]
  • Although ↓ protein intake decreases ammonia Ammonia A colorless alkaline gas. It is formed in the body during decomposition of organic materials during a large number of metabolically important reactions. Note that the aqueous form of ammonia is referred to as ammonium hydroxide. Acid-Base Balance production, protein-caloric malnutrition Malnutrition Malnutrition is a clinical state caused by an imbalance or deficiency of calories and/or micronutrients and macronutrients. The 2 main manifestations of acute severe malnutrition are marasmus (total caloric insufficiency) and kwashiorkor (protein malnutrition with characteristic edema). Malnutrition in children in resource-limited countries is associated with ↑ mortality Mortality All deaths reported in a given population. Measures of Health Status. 
  • Recommended daily protein intake: 1.2–1.5 g/kg/day
  • Use of vegetable protein or oral branched-chain amino acids Amino acids Organic compounds that generally contain an amino (-NH2) and a carboxyl (-COOH) group. Twenty alpha-amino acids are the subunits which are polymerized to form proteins. Basics of Amino Acids (BCAAs) can be given if meat protein intolerance is present. 

Empiric/ammonia-lowering treatment:

• Lactulose Lactulose A synthetic disaccharide used in the treatment of constipation and hepatic encephalopathy. It has also been used in the diagnosis of gastrointestinal disorders. Laxatives:^[5,8,9]
  • Converted to lactic acid by intestinal flora → acidification leads to conversion of ammonia Ammonia A colorless alkaline gas. It is formed in the body during decomposition of organic materials during a large number of metabolically important reactions. Note that the aqueous form of ammonia is referred to as ammonium hydroxide. Acid-Base Balance (NH₃) to ammonium (NH₄⁺) → ammonium is excreted in the feces → ↓ 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 
  • Given orally, rectally, or via nasogastric tube Nasogastric tube Malnutrition in children in resource-limited countries
  • Dose:
    • Prevention (oral): 20–30 g 2–4x/day, titrated to produce at least 3 bowel movements per day 
    • Acute decompensation (oral): 20–30 g every 1–2 hours until 2 soft bowel movements occur, then reduce to prevention dosing
• Lactitol:
  • Ammonium detoxicant
  • Not available in the US
  • Dose: 30–60 g 2–4x/day
• Rifaximin Rifaximin A synthetic rifamycin derivative and anti-bacterial agent that is used for the treatment of gastroenteritis caused by Escherichia coli infections. It may also be used in the treatment of hepatic encephalopathy. Hepatic Encephalopathy:^[8,9]
  • Nonabsorbable antibiotic to decrease the intestinal bacterial load
  • Used in patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship who do not initially respond to, or cannot tolerate, lactulose Lactulose A synthetic disaccharide used in the treatment of constipation and hepatic encephalopathy. It has also been used in the diagnosis of gastrointestinal disorders. Laxatives 
  • Can be used alone, but more commonly used in conjunction with lactulose Lactulose A synthetic disaccharide used in the treatment of constipation and hepatic encephalopathy. It has also been used in the diagnosis of gastrointestinal disorders. Laxatives
  • Dose (oral): 550 mg 2x/day or 400 mg 3x/day
• Monitoring for improvement is based on the clinical exam, not ammonia Ammonia A colorless alkaline gas. It is formed in the body during decomposition of organic materials during a large number of metabolically important reactions. Note that the aqueous form of ammonia is referred to as ammonium hydroxide. Acid-Base Balance levels.

Alternative or additional agents (for those unresponsive to conventional therapy):^[5,8,9]

• BCAAs:
  • Believed that ↑ ratio of aromatic amino acids Aromatic amino acids Amino acids containing an aromatic side chain. Basics of Amino Acids (AAs)/BCAAs leads to encephalopathy Encephalopathy Hyper-IgM Syndrome
  • Oral BCAAs improve the manifestations of episodic HE in some trials.
  • Not available in the US
• Intravenous (IV) L-ornithine L-aspartate (LOLA):
  • Decreases ammonia Ammonia A colorless alkaline gas. It is formed in the body during decomposition of organic materials during a large number of metabolically important reactions. Note that the aqueous form of ammonia is referred to as ammonium hydroxide. Acid-Base Balance (enhances metabolism to glutamine Glutamine A non-essential amino acid present abundantly throughout the body and is involved in many metabolic processes. It is synthesized from glutamic acid and ammonia. It is the principal carrier of nitrogen in the body and is an important energy source for many cells. Synthesis of Nonessential Amino Acids)
  • Not available in the US
• Antibiotics:
  • Neomycin:
    • Glutaminase inhibitor
    • Unclear efficacy for HE
    • Dose: 1 g 2x/day
    • Potential long-term adverse effects: nephrotoxicity Nephrotoxicity Glycopeptides, ototoxicity Ototoxicity Damage to the ear or its function secondary to exposure to toxic substances such as drugs used in chemotherapy; immunotherapy; or radiation. Glycopeptides
  • Metronidazole Metronidazole A nitroimidazole used to treat amebiasis; vaginitis; trichomonas infections; giardiasis; anaerobic bacteria; and treponemal infections. Pyogenic Liver Abscess:
    • Efficacy noted in limited trials 
    • Prolonged use associated with neurotoxicity
  • Vancomycin Vancomycin Antibacterial obtained from streptomyces orientalis. It is a glycopeptide related to ristocetin that inhibits bacterial cell wall assembly and is toxic to kidneys and the inner ear. Glycopeptides (oral): Long-term use increases risk for vancomycin-resistant enterococci Vancomycin-Resistant Enterococci Multidrug-resistant Organisms and Nosocomial Infections.

Liver transplantation Liver transplantation The transference of a part of or an entire liver from one human or animal to another. Hepatocellular Carcinoma (HCC) and Liver Metastases is indicated in:^[5,7] 

• Liver failure Liver 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
• Recurrent intractable OHE

Management of covert HE 

• According to the American Association for the Study of 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 Diseases:^[5]
  • Routine treatment is not recommended.
  • These cases should be reviewed individually.
• According to the European Association for the Study of the 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:^[7]
  • In patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship with cirrhosis Cirrhosis Cirrhosis is a late stage of hepatic parenchymal necrosis and scarring (fibrosis) most commonly due to hepatitis C infection and alcoholic liver disease. Patients may present with jaundice, ascites, and hepatosplenomegaly. Cirrhosis can also cause complications such as hepatic encephalopathy, portal hypertension, portal vein thrombosis, and hepatorenal syndrome. Cirrhosis (no history of overt HE), screening Screening Preoperative Care for covert HE is recommended.
    • Covert HE affects quality Quality Activities and programs intended to assure or improve the quality of care in either a defined medical setting or a program. The concept includes the assessment or evaluation of the quality of care; identification of problems or shortcomings in the delivery of care; designing activities to overcome these deficiencies; and follow-up monitoring to ensure effectiveness of corrective steps. Quality Measurement and Improvement of life and increases the risk of overt HE.
    • Use the screening Screening Preoperative Care tool Animal Naming Test (i.e., the number of 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 listed in 60 seconds).
  • In those who are diagnosed with covert HE, treatment with lactulose Lactulose A synthetic disaccharide used in the treatment of constipation and hepatic encephalopathy. It has also been used in the diagnosis of gastrointestinal disorders. Laxatives or lactitol (and/or rifaximin Rifaximin A synthetic rifamycin derivative and anti-bacterial agent that is used for the treatment of gastroenteritis caused by Escherichia coli infections. It may also be used in the treatment of hepatic encephalopathy. Hepatic Encephalopathy) can be initiated.

Prophylaxis Prophylaxis Cephalosporins (for type C hepatic encephalopathy Encephalopathy Hyper-IgM Syndrome)^[5,7,10]

• Primary prophylaxis Prophylaxis Cephalosporins: generally not required, but recommended in patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship with cirrhosis Cirrhosis Cirrhosis is a late stage of hepatic parenchymal necrosis and scarring (fibrosis) most commonly due to hepatitis C infection and alcoholic liver disease. Patients may present with jaundice, ascites, and hepatosplenomegaly. Cirrhosis can also cause complications such as hepatic encephalopathy, portal hypertension, portal vein thrombosis, and hepatorenal syndrome. Cirrhosis with a high risk for the development of HE
• Secondary prophylaxis Prophylaxis Cephalosporins (recommended after an episode of OHE):
  • Lactulose Lactulose A synthetic disaccharide used in the treatment of constipation and hepatic encephalopathy. It has also been used in the diagnosis of gastrointestinal disorders. Laxatives: associated with less recurrence
  • Rifaximin Rifaximin A synthetic rifamycin derivative and anti-bacterial agent that is used for the treatment of gastroenteritis caused by Escherichia coli infections. It may also be used in the treatment of hepatic encephalopathy. Hepatic Encephalopathy: added to lactulose Lactulose A synthetic disaccharide used in the treatment of constipation and hepatic encephalopathy. It has also been used in the diagnosis of gastrointestinal disorders. Laxatives if patient has ≥ 1 episode of HE while on lactulose Lactulose A synthetic disaccharide used in the treatment of constipation and hepatic encephalopathy. It has also been used in the diagnosis of gastrointestinal disorders. Laxatives

Differential Diagnosis

• Wilson disease Wilson disease Wilson disease (hepatolenticular degeneration) is an autosomal recessive disorder caused by various mutations in the ATP7B gene, which regulates copper transport within hepatocytes. Dysfunction of this transport mechanism leads to abnormal copper accumulations in the liver, brain, eyes, and other organs, with consequent major and variably expressed hepatic, neurologic, and psychiatric disturbances. Wilson Disease: caused by a defect in copper Copper A heavy metal trace element with the atomic symbol cu, atomic number 29, and atomic weight 63. 55. Trace Elements transport within hepatocytes Hepatocytes The main structural component of the liver. They are specialized epithelial cells that are organized into interconnected plates called lobules. Liver: Anatomy. Commonly presents in young adults with 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 disease, neurologic manifestations, and psychiatric symptoms, which may be confused with hepatic encephalopathy Encephalopathy Hyper-IgM Syndrome; however, Wilson’s disease is associated with Kayser-Fleischer rings Kayser-Fleischer rings Copper deposits in Descemet’s membrane of the cornea, manifested as green-brown rings that encircle the iris. Wilson Disease, low plasma Plasma The residual portion of blood that is left after removal of blood cells by centrifugation without prior blood coagulation. Transfusion Products ceruloplasmin Ceruloplasmin A multi-copper blood ferroxidase involved in iron and copper homeostasis and inflammation. Wilson Disease, and high urinary copper Copper A heavy metal trace element with the atomic symbol cu, atomic number 29, and atomic weight 63. 55. Trace Elements excretion. Chelating agents are required for treatment.
• Toxic-metabolic encephalopathy Encephalopathy Hyper-IgM Syndrome: a disruption of normal physiologic functions in the brain Brain The part of central nervous system that is contained within the skull (cranium). Arising from the neural tube, the embryonic brain is comprised of three major parts including prosencephalon (the forebrain); mesencephalon (the midbrain); and rhombencephalon (the hindbrain). The developed brain consists of cerebrum; cerebellum; and other structures in the brain stem. Nervous System: Anatomy, Structure, and Classification caused by other conditions, such as infection, renal dysfunction, electrolyte abnormalities, and medications.  Patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship present with somnolence, disorientation Disorientation St. Louis Encephalitis Virus, motor Motor Neurons which send impulses peripherally to activate muscles or secretory cells. Nervous System: Histology abnormalities, or seizure. Asterixis Asterixis Hepatic Encephalopathy is typically not present. Laboratory tests can help distinguish the cause and differentiate the condition from hepatic encephalopathy Encephalopathy Hyper-IgM Syndrome. Treatment focuses on the underlying cause. 
• Ischemic stroke Ischemic Stroke An ischemic stroke (also known as cerebrovascular accident) is an acute neurologic injury that occurs as a result of brain ischemia; this condition may be due to cerebral blood vessel occlusion by thrombosis or embolism, or rarely due to systemic hypoperfusion. Ischemic Stroke: a disease in which poor blood flow Blood flow Blood flow refers to the movement of a certain volume of blood through the vasculature over a given unit of time (e.g., mL per minute). Vascular Resistance, Flow, and Mean Arterial Pressure to the brain Brain The part of central nervous system that is contained within the skull (cranium). Arising from the neural tube, the embryonic brain is comprised of three major parts including prosencephalon (the forebrain); mesencephalon (the midbrain); and rhombencephalon (the hindbrain). The developed brain consists of cerebrum; cerebellum; and other structures in the brain stem. Nervous System: Anatomy, Structure, and Classification results in cell death Cell death Injurious stimuli trigger the process of cellular adaptation, whereby cells respond to withstand the harmful changes in their environment. Overwhelmed adaptive mechanisms lead to cell injury. Mild stimuli produce reversible injury. If the stimulus is severe or persistent, injury becomes irreversible. Apoptosis is programmed cell death, a mechanism with both physiologic and pathologic effects. Cell Injury and Death. Symptoms include focal weakness, numbness, loss of vision Vision Ophthalmic Exam, dysarthria Dysarthria Disorders of speech articulation caused by imperfect coordination of pharynx, larynx, tongue, or face muscles. This may result from cranial nerve diseases; neuromuscular diseases; cerebellar diseases; basal ganglia diseases; brain stem diseases; or diseases of the corticobulbar tracts. The cortical language centers are intact in this condition. Wilson Disease, and altered mental status Altered Mental Status Sepsis in Children.  Asterixis Asterixis Hepatic Encephalopathy is not seen. Computed tomography and magnetic resonance imaging (MRI) of the brain Brain The part of central nervous system that is contained within the skull (cranium). Arising from the neural tube, the embryonic brain is comprised of three major parts including prosencephalon (the forebrain); mesencephalon (the midbrain); and rhombencephalon (the hindbrain). The developed brain consists of cerebrum; cerebellum; and other structures in the brain stem. Nervous System: Anatomy, Structure, and Classification are used for diagnosis, and will differentiate this condition from hepatic encephalopathy Encephalopathy Hyper-IgM Syndrome. Management includes aspirin Aspirin The prototypical analgesic used in the treatment of mild to moderate pain. It has anti-inflammatory and antipyretic properties and acts as an inhibitor of cyclooxygenase which results in the inhibition of the biosynthesis of prostaglandins. Aspirin also inhibits platelet aggregation and is used in the prevention of arterial and venous thrombosis. Nonsteroidal Antiinflammatory Drugs (NSAIDs), statins Statins Statins are competitive inhibitors of HMG-CoA reductase in the liver. HMG-CoA reductase is the rate-limiting step in cholesterol synthesis. Inhibition results in lowered intrahepatocytic cholesterol formation, resulting in up-regulation of LDL receptors and, ultimately, lowering levels of serum LDL and triglycerides. Statins, and treatment of risk factors.
• Encephalitis Encephalitis Encephalitis is inflammation of the brain parenchyma caused by an infection, usually viral. Encephalitis may present with mild symptoms such as headache, fever, fatigue, and muscle and joint pain or with severe symptoms such as seizures, altered consciousness, and paralysis. Encephalitis: a disruption of normal brain Brain The part of central nervous system that is contained within the skull (cranium). Arising from the neural tube, the embryonic brain is comprised of three major parts including prosencephalon (the forebrain); mesencephalon (the midbrain); and rhombencephalon (the hindbrain). The developed brain consists of cerebrum; cerebellum; and other structures in the brain stem. Nervous System: Anatomy, Structure, and Classification function due to 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, most commonly from a virus Virus Viruses are infectious, obligate intracellular parasites composed of a nucleic acid core surrounded by a protein capsid. Viruses can be either naked (non-enveloped) or enveloped. The classification of viruses is complex and based on many factors, including type and structure of the nucleoid and capsid, the presence of an envelope, the replication cycle, and the host range. Virology. Patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship can have altered mental status Altered Mental Status Sepsis in Children, headache Headache The symptom of pain in the cranial region. It may be an isolated benign occurrence or manifestation of a wide variety of headache disorders. Brain Abscess, 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, seizures Seizures A seizure is abnormal electrical activity of the neurons in the cerebral cortex that can manifest in numerous ways depending on the region of the brain affected. Seizures consist of a sudden imbalance that occurs between the excitatory and inhibitory signals in cortical neurons, creating a net excitation. The 2 major classes of seizures are focal and generalized. Seizures, and movement disorders. Brain Brain The part of central nervous system that is contained within the skull (cranium). Arising from the neural tube, the embryonic brain is comprised of three major parts including prosencephalon (the forebrain); mesencephalon (the midbrain); and rhombencephalon (the hindbrain). The developed brain consists of cerebrum; cerebellum; and other structures in the brain stem. Nervous System: Anatomy, Structure, and Classification imaging may be helpful, but lumbar puncture Lumbar Puncture Febrile Infant with cerebrospinal fluid Cerebrospinal Fluid A watery fluid that is continuously produced in the choroid plexus and circulates around the surface of the brain; spinal cord; and in the cerebral ventricles. Ventricular System: Anatomy analysis is required for diagnosis and to differentiate encephalitis Encephalitis Encephalitis is inflammation of the brain parenchyma caused by an infection, usually viral. Encephalitis may present with mild symptoms such as headache, fever, fatigue, and muscle and joint pain or with severe symptoms such as seizures, altered consciousness, and paralysis. Encephalitis from hepatic encephalopathy Encephalopathy Hyper-IgM Syndrome. Treatment depends on the causative agent and includes antivirals, antibiotics, and supportive care.
• Wernicke encephalopathy Encephalopathy Hyper-IgM Syndrome: a neurologic complication of thiamine Thiamine Also known as thiamine or thiamin, it is a vitamin C12H17N4OSCl of the vitamin B complex that is essential to normal metabolism and nerve function and is widespread in plants and animals Water-soluble Vitamins and their Deficiencies deficiency, usually seen with chronic alcohol dependence. Patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship may present with disorientation Disorientation St. Louis Encephalitis Virus, agitated delirium Delirium Delirium is a medical condition characterized by acute disturbances in attention and awareness. Symptoms may fluctuate during the course of a day and involve memory deficits and disorientation. Delirium, oculomotor dysfunction, gait ataxia Gait ataxia Impairment of the ability to coordinate the movements required for normal ambulation (walking) which may result from impairments of motor function or sensory feedback. This condition may be associated with brain diseases (including cerebellar diseases and basal ganglia diseases); spinal cord diseases; or peripheral nervous system diseases. Friedreich Ataxia, or coma Coma Coma is defined as a deep state of unarousable unresponsiveness, characterized by a score of 3 points on the GCS. A comatose state can be caused by a multitude of conditions, making the precise epidemiology and prognosis of coma difficult to determine. Coma. This is a clinical diagnosis, so history and exam should help differentiate Wernicke’s encephalopathy Encephalopathy Hyper-IgM Syndrome from hepatic encephalopathy Encephalopathy Hyper-IgM Syndrome. Treated with intravenous thiamine Thiamine Also known as thiamine or thiamin, it is a vitamin C12H17N4OSCl of the vitamin B complex that is essential to normal metabolism and nerve function and is widespread in plants and animals Water-soluble Vitamins and their Deficiencies.