Objective 

To evaluate in a large group of volunteer blood donors the prevalence of antibodies to hepatitis C virus (anti-HCV) and the relation of transaminase (ALT) levels and viraemia to liver damage.

Design 

A prospective study.

Setting 

Transfusion Centre of the Autonomous Community of Madrid and the Liver Unit of the Princesa University Hospital.

Patients 

From a population of 55 587 volunteer blood donors, 160 seropositive cases were further evaluated for virological and histological assessment.

Methods 

Anti-HCV was tested by ELISA-2 and RIBA-2 assays.

HCV RNA was analysed by nested PCR.

Liver biopsies were obtained in 35 volunteer blood donors with abnormal ALT levels.

Results 

The prevalence of anti-HCV detected by ELISA-2 was 0.93%. Serum ALT was abnormal in 61 of the 160 volunteers (38.1%). Of these, RIBA-2 was positive in 96.7% and HCV RNA was detectable in 96.1%. Serum ALT was normal in the remaining 99,70.7% being RIBA-2 negative and 98.3% HCV RNA negative.

The majority of biopsies (85.6%) showed chronic hepatitis.

Conclusion 

This study demonstrates that in blood donors screening for anti-HCV, a positive ELISA-2 test, when associated with abnormal ALT levels, is effective in recognizing subjects with active infection detected by HCV RNA and liver disease.

Concerning ELISA-2 positive volunteer blood donors with normal ALT, long-term studies are warranted to elucidate whether they are really infected by HCV.