Hepatitis D Virus
Classification General Characteristics Structure Features Epidemiology Pathogenesis Transmission Transmission of hepatitis D is similar to that of hepatitis B. Host risk factors Pathophysiology Clinical Presentation General Coinfection Superinfection Diagnosis and Management Diagnosis Table: Hepatitis D infection Serum markers Acute HBV/HDV coinfection Acute HDV superinfection Chronic HDV infection HBsAg Positive Positive Positive Anti-HBc IgM Positive Negative […]
Hepatitis A Virus
Classification General Characteristics Structure Basic features Epidemiology Pathogenesis Transmission Risk factors Pathophysiology Clinical Presentation General features Specific symptoms The presence of 1 of the following symptoms is a reason to suspect hepatitis A infection, especially in the presence of risk factors: Diagnosis and Management Diagnosis Management Prevention Comparison of Hepatitis Viruses Differential Diagnosis References
Rhinovirus
Classification General Characteristics Structure Picornavirus family RNA virus Positive-sense ssRNA Naked Basic features Very small: 30 nm Acid-labile → inactivated by gastric acid Temperature for proliferation: 33–35°C (found in the nose) > 100 serotypes can cause upper respiratory infections (the common cold). Capable of surviving on hands for hours Associated diseases Upper respiratory tract infections […]
Mycology
Growth Forms and Reproduction Growth forms Structure Reproduction Reproduction is either sexual or asexual. Toxic Products of Fungi Table: Toxic products of fungi Toxin Fungus Effect Aflatoxin Aspergillus flavus A. parasiticus Highly carcinogenic and often the cause of food poisoning (traces on nuts, grain, spices) Amanitin Amanita phalloides (death cap mushroom) Inhibition of RNA polymerase […]
Epidemic Typhus
Overview Definition Epidemic typhus is a potentially lethal, febrile illness caused by the obligate intracellular gram-negative bacterium, Rickettsia prowazekii. Epidemiology Transmission: Risk factors: Geography: Etiology and Pathophysiology Etiology Pathophysiology Clinical Presentation Diagnosis and Management Diagnosis Management Antibiotics: Prevention: Prognosis: Differential Diagnosis References
Hepatitis E Virus
Classification General Characteristics Structure Basic features Epidemiology Pathogenesis Transmission Host risk factors Pathophysiology Primary replication: Clinical Presentation Diagnosis and Management Diagnosis Management Prevention Comparison of Hepatitis Viruses Table: Comparison of hepatitis viruses A–E Differential Diagnosis References
Paracoccidioides/Paracoccidioidomycosis
General Characteristics of Paracoccidioides Features Morphology: Thermally dimorphic fungus Mold forms at 22°C–26°C Yeast forms at 37°C Mold form: thin, septated hyphae Yeast form: Oval/round budding yeast “Pilot’s wheel” or “Captain’s wheel” appearance: large cell surrounded by budding cells Clinically relevant species P. brasiliensis P. lutzii Forms of disease Asymptomatic lung infection Acute/subacute Chronic Epidemiology […]
Histoplasma/Histoplasmosis
General Characteristics of Histoplasma Features Morphology: thermally dimorphic fungus Ambient (low) temperature: mold form Body (high) temperature: yeast form Characteristics: Obligate aerobe Mold form: Septate mycelium: thin and branching Produce microconidia and tuberculate macroconidia Yeast form: Reproduce by budding Slightly oval 2–4 µm in diameter Found exclusively in macrophages Clinically relevant species H. capsulatum var. […]
Human Herpesvirus 8
Classification General Characteristics and Epidemiology General features of human herpesvirus 8 (HHV-8) Associated diseases Epidemiology Pathogenesis Reservoir Humans are the only known reservoir. Transmission It is not entirely clear how the virus is transmitted. Host risk factors Human herpesvirus 8 infection is usually asymptomatic. Clinical manifestations can occur in immunocompromised patients: Viral replication cycle Pathophysiology […]
Human Herpesvirus 6 and 7
Classification General Characteristics and Epidemiology Basic features of HHV-6 and HHV-7 Associated diseases The clinical relevance of HHV-6A is not entirely known. Epidemiology Pathogenesis Reservoir Humans are the reservoir for HHV-6 and HHV-7. Transmission HHV-6 and HHV-7 are transmitted through contact with saliva. Pathophysiology Clinical Presentation Human herpesvirus-6 infections are usually mild and occur during […]