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This update provides a comprehensive overview of Hepatitis C, detailing its transmission, diagnosis, and treatment from a primary care perspective. With approximately 4 million Americans infected, Hepatitis C is the leading cause of liver disease and transplantation. Key points include the natural progression to chronic infection, risk factors for cirrhosis and hepatocellular carcinoma, and the importance of both patient education and management plans. The evolving landscape of treatment options, including interferon and ribavirin therapies, is also discussed.
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Hepatitis C Update: A Primary Care Perspective Jay Fathi, M.D. February 2003
Overview—an epidemic • RNA virus; discovered by cloning in 1988 • First serologic test 1990 • Approximately 4 million Americans infected; most common liver disease in US, most common indication for transplantation • Roughly 30,000 new cases annually; only 30% diagnosed
Overview (cont.) • 85% become chronically infected • 10,000 deaths annually • Incidence falling recently; prevalence increasing over last decade
Natural Course • Acute infection: asymptomatic or mild illness • Virus detectable by PCR-RNA in 2-4 weeks after exposure usually • Roughly 15% spontaneously clear virus; remain Ab-positive but are PCR-RNA negative • 20% (3-30% depending on study) develop cirrhosis, usually over many years • Alcohol, co-morbid HIV, Hep B increase risk
Natural Course (cont.) • 20% cirrhotic patients (5% of total) develop hepatocellular carcinoma; survival after Dx of HCC is 6 months-2 years • Clinic course varies greatly case by case
Transmission • Contaminated blood most infectious (transfusions prior to 1992, now needle-sharing, intranasal cocaine) • Sexual transmission (less than 5%) • Perinatal transmission (approx. 5%); dependent on maternal viral load • Shared razors, toothbrushes, open cuts, etc.
Transmission (cont.) • Occupational exposure (roughly 2% with needlesticks) • ALWAYS USE UNIVERSAL PRECAUTIONS
Diagnosis • Enzyme immunoassays • PCR (viral load), qualitative vs. quantitative useful to follow treatment response • Viral load not correlated with disease progression • Genotyping (when considering treatment) • Complete Hep screen, HIV
LFTs • LFTs are not well correlated with hepatic fibrosis • Fairly specific; poor sensitivity • Normal LFTs somewhat reassuring, but hepatic fibrosis can still exist • Biopsy-gold standard for assessing disease progression
Patient Education • Avoid hepatotoxins (esp. ALCOHOL!!!) • General healthcare maintenance (diet, smoking cessation, exercise, etc.) • Weight loss—can help steatosis and may possibly alter course of disease • Immunizations (Hep A, B, pneumovax, Td, flu shot, etc.)
Education (cont.) • Do not donate blood, share needles or inhalation devices for recreational drugs, cover wounds, discuss possible sexual/perinatal transmission • Support groups
Treatment • 18-60 years old (**) • Persistently elevated LFTs (?) • PCR positive, biopsy positive • Studies currently ongoing in other populations (children, older adults, severe cirrhotics, etc.)
Treatment (cont.) • No current substance abuse • Patient interested in therapy • *No current substance abuse, generally healthy, no unstable psychiatric disorders*
Treatment (cont.) • Interferon plus oral ribavirin • Usually 12 months, 1-3 weekly injections, very costly ($15,000 for Ribavirin alone) • Side effects –flu-like symptoms, alopecia, bone marow suppression, cardiac and pulmonary impairment, thyroid/ocular abnormalities, seizures, exacerbation of any pre-existing psychiatric abnormalities
Treatment (cont.) • Pegylated interferon: higher clearance rates, once-weekly injections, less psychiatric SE • Lasting (?) clearance of virus in 20-50% patients • Resposne to treatment somewhat dependent on genotype (1 most prevalent in US, likely most virulent also) • Genotype I, previous non-responders, African Americans less responsive to treatment
Treatment (cont.) • Depression (‘emotional disturbances’) most common reason for discontinuation • 20% or more drop out of treatment before 48 week course completed • Protease Inhibitors: promising preliminary data • Milk thistle? Data shows no improvement
Frequent Co-morbidities • HIV, Hep B, alcohol abuse, other substance abuse, psychiatric disorders (depression, bipolar), homelessness, etc.
Suggested Management Plan • Check PCR; if negative, periodically screen with ALT and/or PCR (Q2-5 years?) to ensure patient has definitively cleared virus • If PCR positive, assess if patient is candidate for therapy and give thorough counselling about disease/treatment/etc. to see if they are interested
Management plan (cont.) • If yes to both (PCR positive, interested in treatment), refer for liver biopsy • Primary care clinician must be able to competently counsel patients regarding the myriad of complicating issues • Each patient must be managed individually
Hepatitis B • Double-stranded DNA virus • Global prevalence: 5% • Approximately 400 million people! • Mostly in SE Asia, Philippines, Middle East, Africa, parts of S. America • Lowest prevalence: US, Canada, N. Europe • US: 1 million chronically infected (chronic carriers)
Transmission • Blood, body fluids (saliva, semen) • Most common mode of spread in US: sexual contact (heterosexual and homosexual) • Most common mode of spreas worldwide: VERTICAL TRANSMISSION
Acute to chronic infection • After acute infection, 5-10% of adults become chronically infected • Up to 90% of neonates become chronically infected when vertical transmission occurs • HBcAB+ evidence of prior infection • HBsAg + chronically infected • HBcAB + and HBsAg negative: prior infection, have cleared virus
Chronic Hep B • HBeAg—indicative of replication and infectivity • HBeAg + “Replicators,” more infections, poor prognosis • 15-20% progress to cirrhosis in 5 years • HBeAg negative---- “Non-replicators,” less infectious, better prognosis • Both should be referred to specialist for likely liver biopsy, treatment evaluation
Treatment • Interferon, 3TC (lamivudine) • Fairly low numbers re: response rates • Hepsera (Adefovir)—new treatment • 50-60% ‘cure rate’ (?) in studies • Liver fibrosis improved on biopsy • SE: 25% can experience exacerbation of hepatitis
Prevention • IMMUNIZATION !!!!!!!!!!!!!!!!!!!!!!!!! • ALL infants • High risk adults • All adults?