chronic hepatitis C

chronic hepatitis C
Name	Chronic hepatitis C
Caption	Diagram of the Hepatitis C virus particle.
Field	Infectious disease, Hepatology
Symptoms	Often asymptomatic; can include fatigue, jaundice, abdominal pain
Complications	Cirrhosis, Hepatocellular carcinoma, Liver failure
Duration	Lifelong without treatment
Causes	Infection by Hepatitis C virus
Risks	Intravenous drug use, unsafe medical procedures, Blood transfusion
Diagnosis	Antibody testing, HCV RNA testing, Liver biopsy
Treatment	Direct-acting antiviral medications
Prevention	Screening of blood donations, harm reduction programs
Frequency	~58 million globally (WHO estimate)
Deaths	~290,000 annually

chronic hepatitis C is a persistent infection with the Hepatitis C virus that leads to ongoing inflammation of the liver. It is a major global cause of Cirrhosis and primary liver cancer, often progressing silently for decades before significant liver damage becomes apparent. The advent of Direct-acting antiviral therapies has transformed its management, offering high cure rates.

Signs and symptoms

Most individuals with chronic hepatitis C are asymptomatic for many years. When symptoms do occur, they are often non-specific and may include profound fatigue, mild right upper quadrant abdominal discomfort, and joint pains. More overt signs of advanced liver disease can emerge, such as jaundice, ascites, and confusion due to increased portal pressure. Itching and the appearance of spider angiomas are associated with impaired bile flow and hormonal changes.

Causes and transmission

The sole cause is persistent infection with the Hepatitis C virus, a member of the Flaviviridae family. The primary mode of transmission globally is through exposure to infected blood. This historically occurred via unscreened blood transfusions and blood products, a risk largely mitigated in countries following guidelines from the AABB and FDA. Presently, sharing injection equipment is the most common route. Other risks include unsafe medical injections, long-term hemodialysis, and occupational needlestick injuries among healthcare workers. Mother-to-child transmission occurs in a minority of births, and sexual transmission is considered inefficient.

Diagnosis

Diagnosis is a two-step process beginning with a serological test for HCV antibodies, such as the enzyme-linked immunosorbent assay. A positive antibody test indicates exposure but not necessarily ongoing infection, necessitating confirmation with a nucleic acid test for HCV viral RNA, which confirms active viremia. Following diagnosis, assessment of liver fibrosis is critical, which can be done non-invasively via transient elastography (FibroScan) or serum markers like the FIB-4 index, or invasively via percutaneous liver biopsy. Viral genotyping is performed to guide antiviral therapy selection.

Treatment

The standard of care is therapy with direct-acting antiviral medications, which target specific proteins of the Hepatitis C virus such as NS5A, NS5B polymerase, and NS3/4A protease. Regimens like sofosbuvir/velpatasvir or glecaprevir/pibrentasvir achieve sustained virological response, considered a cure, in over 95% of patients across all major genotypes. These oral regimens, typically lasting 8 to 12 weeks, have largely replaced older therapies involving pegylated interferon and ribavirin. Treatment decisions are informed by the AASLD and IDSA guidelines.

Prognosis and complications

The natural history is highly variable; many live for decades without major sequelae, while others progress to compensated cirrhosis within 20 to 30 years. Major complications arise from advanced portal hypertension and include bleeding esophageal varices, hepatic encephalopathy, and kidney failure. The most feared complication is the development of hepatocellular carcinoma, which carries a high mortality rate. Extrahepatic manifestations are common and can involve the immune system, leading to conditions like mixed cryoglobulinemia, B-cell non-Hodgkin lymphoma, and membranoproliferative glomerulonephritis.

Epidemiology

The World Health Organization estimates approximately 58 million people have chronic infection globally, with about 1.5 million new acute infections annually. Prevalence is highly heterogeneous, with historically high rates in regions like Egypt (linked to past schistosomiasis treatment campaigns) and Pakistan. In the United States, the CDC identifies the highest incidence among adults born between 1945 and 1965. Major initiatives like the WHO Global Health Sector Strategy aim for elimination by 2030 through expanded screening and treatment access.

Category:Hepatitis C Category:Viral diseases Category:Chronic diseases