Term
HAV
morphology
transmission
clinical
serology
misc |
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Definition
Picorna virus
+ SS RNA
Naked
Icosahedral capsid
Fecal-oral
Shellfish, contaminated H2O
Acute viral hepatitis: fever, jaundice, painful enlarged liver
Never becomes chronic
Anti-HAV IgM = active disease
Anti-HAV IgG = Old, no active disease, protective for life
HAV you washed your hands?
unlike B & C, it's self-limiting, you don't get chronic disease |
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Term
HBV
morphology
transmission
clinical
serology
misc |
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Definition
Hepadna virus
DS circular DNA
Envelope
Icosahedral
Dane particle (intact virus)
-envelope
-capsid associated proteins
-capsid
-core (DNA + protein enzymes)
HBsAg: envelope, capsid assoc proteins
HBcAg: DS DNA, DNA polymerase, capsid
HBeAg: soluble component of the core, marker for active disease
Dissociation of the Dane particles leaves HBsAg and HBcAg
Blood transfusion
needle sticks
sexual
across placenta (90% if mom is HBeAg+)
Acute viral hepatitis
Fulminant hepatitis: severe acute with rapid destruction of liver
Chronic hepatitis (10%):
-asymptomatic carrier
-chronic persistent hepatitis
-chronic active hepatitis
Coinfection or superinfection with HDV
Complications: *primary hepatocellular carcinoma, Cirrhosis*
HBsAg = disease (acute or chronic)
Anti-HBsAg = immunity
IgM anti-HBcAg = new infxn
IgG anti-HBcAg = old infxn
HBeAg = high infectivity
Anti-HBeAg = low infectivity
During window period, the only detectable marker is anti-HBcIgM
Only HBV carries a DNA polymerase enzyme within the virion (catalyzes the formation of the cell's DNA)
Liver injury occurs from a CMI attack on HBV
Carrier: persistence of HBsAg > 6 mo, w/o sx |
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Term
HCV
morphology
transmission
clinical
serology
misc |
|
Definition
Probably Flavivirus
SS RNA
Enveloped icosahedral
Blood transfusion
Needle sticks (drug users, medical personnel)
Sexual (low risk)
Placental (<10%)
Acute viral hepatitis
-up to 85% develop chronic hepatitis
-20% will develop cirrhosis
-i/c risk of developing primary hepatocellular carcinoma
Screening: anti-HCV Ab
doesn't distinguish b/t acute and resolved
HCV is leading cause for liver transplantion
PCR used to detect viral RNA, can be used to detect active infxn |
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Term
HDV
morphology
transmission
clinical
serology |
|
Definition
incomplete RNA virus - only infective with help of HBV
Helical nucleocapsid that requires HBV envelop (HBsAg) to be infective
blood transfusion, needles, sex, placenta
Coinfection: HBV and HDV are acquired simultaneously, cause acute hepatitis.
Superinfection: HDV infects pt with chronic HBV who can't make Anti-HBsAg Ab
-complications: fulminant hepatitis, cirrhosis
Serology isn't very helpful; detectable titers of IgM and IgG anti-HDV are present fleetingly |
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Term
HEV
morphology
transmission
clinical
misc |
|
Definition
Hepeviridae family
SS RNA
Naked
Fecal-oral
Hepatitis like HAV
Hepatitis epidemics in Asia, very rare in U.S. |
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Term
HIV
Serology
TORCH
AIDS
-opportunistic infxns
-malignancies |
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Definition
ELISA detects Ab, very sensitive but not terribly specific
give second ELISA, then confirm with Western Blot test (+ if it has bands to 2 HIV gene products - p21, gp41, gp120)
CD4 T-lymp count < 200
One of the TORCH pathogens: rate is ~30%, occurs transplacentally, during delivery, and perinatally
Staph aureus or Staph epidermidis
encapsulated: H. influenzae, Strep pneumo
Mycobacterium tb
Mycobacterium avium-intracellulare
UTI in young males
Candida albicans
Cryptococcus neoformans (often won't exhibit meningeal inflammation)
Histoplasma capsulatum, Coccidioides immitis
Herpes zoster
EBV (oral hairy leukoplakia)
HSV
CMV
Pneumocystic carinii pneumonia
Toxoplasma gondii (TORCH) - mass lesions in brains
Crytosporidium, Microsporidia, Isospora belli
B-cell lymphoma (often present with brain mass), half contain EBV DNA
Kaposi's sarcoma (cofactor is HHV-8) |
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