[Hepatitis C. Diagnostic and prognostic aspects from the insurance medicine viewpoint].

Hepatitis C is a chronic infection with potentially serious long-term effects. An acute clinical presentation is the exception, often the disease is only diagnosed through routine screening (e.g. as a blood donor) or work-up for elevated liver enzymes. The silent course of this disease also makes it difficult to interpret epidemiological studies. Potential biases need to be considered which may lead to underestimation or overestimation of prevalence and incidence data. Special attention is needed in evaluating long-term effects as the studies usually deal with small numbers of HCV positives and their selection may not have been randomised. An assessment of the prognosis is difficult, especially in the absence of a series of liver enzyme measurements and if the viral load is unknown. The wide availability of diagnostic tests harbours a potential for anti-selection. Caution is therefore required when designing underwriting guidelines; only well documented cases should be accepted. A response to therapy (e.g. with interferon), alone, does not prove a good prognosis, rather, the course over a 2-year follow-up may give relevant prognostic information.