VI- Viral Hepatitis Flashcards
acute hepatitis presentation
- jaundice
- dark urine
- acholic stool (light or clay colored)
- prodrome- headache, myalgia, arthralgia, fatigue, nausea, vomit, pharyngitis, fever
acute hepatitis lab values
- bilirubin > 3, typically b/t 5-20
- ALT and AST
chronic hepatitis definition
hepatitis that doesn’t resolve in 6 mo
-predisposes to liver cirrhosis and hepatocellular carcinoma
fulminant hepatitis presentation
- rapid, severe hepatitis
- massive hepatic necrosis
- encephalopathy
- edema
complications of fulminant hepatitis
- cerebral edema
- brainstem compression
- GI bleeding
- sepsis
- organ failure
Hep A features
- picornavirus +ssRNA
- incubation 2-4 weeks
- fecal oral transmission
- no chronic infection
Hep B features
- hepadnavirus dsDNA
- 6 week - 6 m incubation
- body fluid transmission
- yes develop to chronic
Hep C features
- flavivirus- enveloped +ssRNA
- 2 mo incubation
- body fluid transmissin- esp injection drugs
- yes chronic infection
Hep D features
- deltavirus
- 2-12 week incubatin
- body fluid transmissin
- yes chronic
Hep E features
- hepevirus +ssRNA
- 6-8 week incubation
- fecal oral transmission
- no chronic
Hep A diagnosis
- acute infection has IgM Ab
- anti HAV IgG for protective immunity
Hep A outcomes
- resolution within 2 mo
- rarely causes fulminant
og symps usually asymptomatic all age groups
HAV vaccine
-2 doses of inactivated whole virus IM injection
-all kids at 1 should get
-high risk groups include homosex men, travelers, illegal drug users, clotting factor disorders, close contact with international adoptee, occupation
Hep B histology
- dane particles aka complete virions infectious with HBeAg, HBcAg, HBsAg
- tubes and spheres of incomplete noninfectious particles coated by HBsAg
acute HBV antibodies if cleared
- initial rise in IgM anti-HBc
- isotype switch to IgG anti-HBc
will have anti-HBs (surface)
acute HBV antibodies if chronic
- rise and decline of IgM anti-HBc
- anti-HBc (core) instead of surface like clearance
Hep B outcomes
- half are asymptomatic
- if symps then milder than HAV acute hepatitis
Hep B chronic treatments
- oral polymerase inhibitors - lamivudine (nucleoside reverse transcriptase inhib) and tenofovir disoproxil fumarate (acyclic nucleotide analogue polymerase inhib)
- cell intrinsic immune modulator - pegylated interferon (long acting interferon bound to polyethelene glycol) injected
HBV vaccine
-protein vaccine with HBsAg
-IM injection 3 doses for routine vaccination kids or pre exposure high risk adults
groups for post exposure prophylaxis HBV
- premature infants with mothers HBsAg pos or unknown status
- full term infant with HBsAg pos mother
- percutaneous expsoure of health care workers
combo of vaccine + Hep B immunoglobulin
HCV processing
- HCV virion
- +ssRNA genome translated
- immature viral polyprotein proteolysed by HCV NS3/4A
- mature viral proteins replicated by HCV NS5B RdRp and HCV NS5A
- -ssRNA
- virion assembly by HCV NS5A
Hep C testing guidelines
one time for: all indivs 18+, under 18 if inc risk, prenatal care
periodic for: inc risk exposure groups
annual for: injection drug users, HIV infected men, men taking pre-exposure prophylaxis
HCV diagnosis
- screening test for anti-HCV antibodies
- confirmatory test for detection of viral genome
Hep C outcomes
majority develop to chronic, some acute but symps milder than HAV or HBV,
-some rapid progress to cirrhosis
HCV treatments
-combo therapy with direct acting antivirals for 12-24 weeks, no vaccine
-can simplify if chronic without cirrhosis and not previously received treatment
-recommended for all patients acute or chronic
HCV antivirals
- protease inhibitors - glecaprevir, prevents cleavage to mature protein
- RNA polymerase inhibitors - sofosbuvir, prevents genome rep
- HCV HS5A inhibitors - pribentasvir, velpatasvir, stops replication and virion assembly
Hep D structure
small circular ssRNA
-two proteins cover virions (delta short and delta long)
-helper dependent bc needs Hep B surface antigen to form external surface AND replication requires HBV proteins
HDV outcomes
fulminant hepatitis more likely outcome if double infected with B and D
-directly injures hepatocytes instead of immune resp
HDV diagnosis
- elisa to detect anti-HDV antibodies or delta antigens
- no specific treatments
- prevent by HBV vaccine
Hep E treatment
- alleviate symptoms
- prevent by clean water and proper food handling
