Viruses

Question 1

Infection risk from needle stick injury if known HBV, HCV, HIV,CMV?

Answer 1

HBV: 2-40%
HCV: 3-10%
HIV: 0.2-0.5%
CMV: negligible (spread by mucosa-mucosa contact)

Question 2

What complications/infections are increased in patients with AIDS?

Answer 2

Acute abdomen
GI perf
Hep B+C
Candida
Mycobacterium
Splenomegaly
Neoplasia, NHL, kaposis, SCC

Question 3

What is HIV?

Answer 3

Retrovirus
Targets monocytes, macrophage, T-helper cells, microglial cells
Damage due to viral replication and destruction of T helper cells (CD4)
Stored in lymphoid tissue and CNS

Question 4

How is HIV diagnosed?

Answer 4

≥2 screening tests (ELISA) for HIV Abs
Then confirmatory test (western blood or recombinant ELISA) to detect antigen
Can also do viral culture, PCR, Ag detection

Question 5

What is HTLV and what types exist?

Answer 5

Human T lymphocytic virus
HTLV 1 - adult T cell lymphoma, tropical spastic paraparesis
HTLV 2 - hairy cell leukemia
HTLV 3 - HIV1
HTLV 4 - HIV2

Question 6

How is HEP A transmitted?

Answer 6

fecal-oral

Question 7

What is the course of Hep A?

Answer 7

Most often acute in adults

Question 8

Which antibody classes are involved with HepA?

Answer 8

IgM acutely

IgG sub acutely then stays up for immunitty

Question 9

How is HepB transmitted?

Answer 9

Blood

Question 10

What does hep B HBeAG represent?

Answer 10

viral replication and high infectivity

Question 11

What do HepB HBsAG and HBcAG represent?

Answer 11

acute infection

Question 12

What does Hep B anti-HBs represent?

Answer 12

immunity (either from virus or vaccine)

Question 13

Which Hep B antibody suggests viral infection vs vaccination?

Answer 13

anti-HBc because only HBs antigen is used in vaccine, so HBc would only be present if actually caught the virus

Question 14

What percentage of HepC progress to chronic liver disease?

Answer 14

> 50%

Question 15

This strain of hepatitis can only exist in the presence of HepB because it needs HepB to replicate

Answer 15

HepD