GPs should follow up all patients with a mildly raised alanine aminotransferase level to rule out hidden hepatitis C infection, say researchers.
The Dutch study looked at the prevalence of hidden hepatitis C infection in primary care patients and a cut-off for investigating raised ALT levels.
The researchers identified patients referred by their GP for liver enzyme testing with a mildly elevated ALT test result (30-100 IU/l) and grouped them by the different ranges of ALT elevation – 30-50 IU/l, 50-70 IU/l and 70-100 IU/l. Each group contained 250 samples, and each patient was tested for hepatitis C and hepatitis B.
They found prevalence of hepatitis C was not elevated in patients with an ALT level of 30-50 IU/l, but the prevalence of positive anti-hepatitis C test results was 2.0% in the 50-70 IU/l ALT level group and 1.2% in those with an ALT level of 70-100 IU/l.
They concluded that in primary care patients with an ALT elevation between 50 IU/l and 100 IU/l the risk of hepatitis C infection was substantially elevated.
Study lead Professor Charles Helsper, assistant professor and lecturer for GP-specialty training at Utrecht University, said: ‘It is recommended that in all patients with an ALT elevation of 50 UI/l-100 UI/l, particularly those for whom no clear explanation for the ALT elevation is found, diagnostic follow-up for hepatitis C is performed.'
British Journal of General Practice 2012; 62: e212-e216