Hepatitis C Flashcards
acute hepatitis C
infection that develops during the first 6 months following the exposure
chronic hepatitis C
HCV infection that persists beyond 6 months following exposure
Hep C virus pathogen
Hepacivirus C
RNA virus
risk of chronic infection depends on hosts ability to clear infection through activation of innate pathway
6 genotypes
reinfection with another HCV genotype is possible
transmission methods
parenteral - needle shharing among IVDU, needlestick injury, blood transfusion, dialysis
organ transplantation
sexual - rare in contrast to HBV and HIV
perinatal (vertical)
risk factors for HCV infection
injection drug use
HBV or HIV
Hx of incarceration
recieved blood transfusion or organ transplant before 1992
incubation period
2 weeks to 6 months
acute course of disease
asymptomatic in 80% of cases
malaise, fever, myalgias, arthralgias
RUQ pain, tender hhepatomegaly
nausea, vomitng, diarrhoea
jaundice, possibly pruritis (due to elevated bilirubin)
chronic course of disease
seen especially in asymptomatic individuals as treatment may be delayed or not initiated
findings often mild and non specific eg. fatigue
liver cirrhosis
extrahepatic features
extrahepatic features of HCV
haem: mixed cryoglobulinaemia, lymphoma, immune tyhrombocytopaenic purpura, autoimmune hemolytic anaemia, monoclonal gammopathies
renal - membranoproliferative GN, membranous GN
rheum - polyarteritis nodosa, sjogren syndrome
dermatological - porphyria cutanea tarda, lichen planus
endocrine - T2DM, autoimmune thhyroiditis
vascular - leukocytoclastic vasculitis
other - sialadenitis
screening for HCV in people without risk factors
everyone at least once per lifestime age >18
once per pregnancy
the CDC recommends against universal screening in settings where HCV disease prevelance is <0.1%
screening for people with risk factors
one time:
- upon diagnosis with HIV
- individuals <18 years with risk factors
- infants born to HCV pos mothers
repeat screening
- after exposure to HCV within 48 hours and then >6 months
- annual for people who inject drugs, Men with HIV who have unprotected sex with men, Men who have sex with men taking HIV preexposure prophylaxis
Hepatitis C tests for people who are HCV naive
Anti-HCV antibodies (EIA/ELISA immunoassay): as initial test for immunocompetant individuals who are HCV naive
Hepatitis C tests for people with prior HCV infection or immunocompromise
HCV RNA qualitative PCR
after seroconversion from prior HCV infection, HCV antibodies wil;l remain positive for life and have no further diagnostic utility
why are antibody tests less effective in immunocompromise
immunocompromise may prevent people from being able to produce antibodies
seroconversion may be delayed or absent
interpretation of hepatitis C tests
how to tell between acute or chronic infection
in contrast to Hep A and Hep B infections, there is no serologic or virology assay for HCV that distinguishes between acute and chronic infection
how long until antibodies are detectable on immunoassay
as long as 6 weeks
how long until RNA HCV is detectable on qualitative PCR
as long as 2-3 weeks
laboritory studies for workup
quantitative PCR for HCV RNA viral load
routine studies: FBC, UECs
hepatocellular enzymes
cholestasis parameters
liver synthetic function tests
HIV, HAV, HBV for coinfection
serum pregnancy test
hepatocellular enzyme changes
transaminases (ALT and AST)
are involved in amino acid metabolism and used clinically as parameters of hepatocellular injury
will be normal or raised
fluctuating ALT peaks indicate acute HCV infection
cholestasis parameters changes
raised GGT
raised alk phos
raised bilirubin
liver synthetic function tests
alterations indicate cirrhosis
decreased albumin
decreased total protein
increased PT/INR
liver biopsy
consider if aeitiology of hepatitis is unknown
consider if liver fibrosis staging would alter treatment
acute phase pathology
focal areas of macrovesicular steatosis
bile duct injury
sinusoidal inflammation of hepatic cells
lobular involvement in the form of eosinophillic single cell necrosis
chronic phase pathology
lymphoid follicles in portal triad
necroinflammation of periportal liver cells
variable degree of fibrosis
severe hepatocyte injury
general principles of treatment
the goal of treatment is sustained virological response (SVR)
refer patients with end-stage liver disease for liver transplant evaluation
antiviral therapy
always treated with multidrug approach (no antivirals approved for monotherapy)
- direct acting antvirals: antivirals target and inhibit HCV encoded proteins that are essential for the HCV replication cycle
- interferon plus ribavirin was the preferred treatment before the development of DAAs
acute and chronic infections are treated the same
are DAAs or interferon or ribavirin based therapies preferred
DAAs have superior efficacy and safety profiles
supportive care
in all individuals with HCV:
- avoid hepatotoxic drugs and alcohol
- counsel about HIV and hep B prevention
- counsel regarding adherance, reinfection prevention, and medication risks
offer Hep A and B vaccination for Hep A and B seronegative individuals
give harm reduction strategies and refer for treatment for substance abuse for IVDU
