Micro - Virology Part 2 Flashcards
A boy has spots on his oral mucosa that are red with a blue-white center and a maculopapular rash on his chest. What is the cause?
Rubeola (measles) virus; note the Koplik spots on the inner cheek and the diffuse rash
A patient presents with ulcerating painful lesions on her genitals. What is the diagnosis?
Herpes genitalis
How long is the incubation period of the hepatitis B virus?
3 months
What characteristics do hepatitis B and C have in common?
They are both transmitted by blood, they both have chronic carriers, and they both can cause chronic active hepatitis, cirrhosis, and hepatocellular carcinoma
Which patient populations are at high risk for hepatitis C?
Intravenous drug users and posttransfusion patients
Infection with which hepatitis virus requires coinfection with hepatitis B virus?
Hepatitis D virus (remember: Hepatitis D is Defective and Dependent on hepatitis B virus coinfection)
What are two severe long-term sequelae of chronic infection with hepatitis C?
Cirrhosis and carcinoma (remember: Hep C: Chronic, Cirrhosis, Carcinoma Carrier)
A bat researcher develops fever, malaise, photophobia, and coma. He dies. Pathology shows cytoplasmic inclusions in his neurons. Etiology?
Rabies virus; note the Negri bodies on histopathology, which are characteristic of rabies
Which has a worse prognosis: coinfection with hepatitis B and hepatitis D, or superinfection of hepatitis D in a patient with hepatitis B?
Superinfection leads to more severe illness
Which two types of hepatitis are trasmitted through the bowels?
Hep A (primarily fecal-oral) and hep E (enteric) (remember: “the vowels hit your bowels”)
Why are hepatitis A and E viruses infectious via the fecal-oral route, whereas hepatitis B, C, and D are not?
Because enveloped viruses (B, C, D) are destroyed by the gut whereas naked viruses (A, E) are not
What are the signs and symptoms of hepatitis infection?
Episodic fevers, jaundice, and elevated aspartate aminotransferase and alanine aminotransferase levels
Which serologic marker indicates prior infection with and is protective against reinfection with hepatitis A infection?
Immunoglobulin G hepatitis A virus antibody
Which serologic marker detects active hepatitis A infection?
Immunoglobulin M hepatitis A virus antibody
What does the continued presence of hepatitis B surface antigen in serum mean?
A chronic infection and carrier status for the patient
Which antibody is protective against hepatitis B infection?
Hepatitis B surface antibody
Which hepatitis serologic marker is positive during the “window period”?
Hepatitis B core antibody
What is the significance of immunoglobulin M hepatitis B core antibody vs immunoglobulin G hepatitis B core antibody on serologic studies?
Regarding hepatitis B virus core antibodies, immunoglobulin M is a marker for recent disease whereas immunoglobulin G is a marker for chronic disease
What is the significance of hepatitis B envelope antigen?
The level of the envelope antigen in serum is a marker of the infectivity of the patient because it indicates active viral replication
What does the presence of hepatitis B e antibody indicate?
Presence of antibodies to the envelope antigen indicates lower transmissibility
The presence of which hepatitis B serologic marker would be seen in an asymptomatic patient in the hepatitis B incubation period?
Hepatitis B surface antigen
What pattern of transaminase elevation is seen in viral hepatitis? In alcoholic hepatitis?
In viral hepatitis, alanine aminotransferase > aspartate aminotransferase; in alcoholic hepatitis, aspartate aminotransferase > alanine aminotransferase
In acute hepatitis B virus infection, hepatitis B surface antigen tests would be (+/-) _____, hepatitis B surface antibody would be (+/-) _____, and hepatitis B core antibody would be (+/-) _____.
Positive; negative; positive (immunoglobulin M hepatitis B core antibody in acute stage, immunoglobulin G hepatitis B core antibody in chronic or recovered phase)
In the window phase of hepatitis B virus infection, hepatitis B surface antigen tests would be (+/-) _____, hepatitis B surface antibody would be (+/-) _____, and hepatitis B core antibody would be (+/-) _____.
Hepatitis B surface antigen negative; hepatitis B surface antibody negative; hepatitis B core antibody positive