Serum levels of anti-hepatitis C virus IgM core antibodies may predict the response to interferon-alpha therapy in chronic hepatitis C.

We measured the optical densities (OD) of serum anti-hepatitis C virus IgM core antibodies in 40 HCV-positive patients (24 males and 16 females) with histologically proven chronic active hepatitis but without cirrhosis. All patients were treated with i.m. injections of 3 MU thrice weekly of interferon-alpha (IFN-alpha) for 6 months and followed-up monthly. Optical densities were evaluated in thawed sera before beginning treatment and 6 months after completion, and in fresh sera obtained at the end of an 8-12-month follow-up period. Patients were grouped into three categories according to the OD obtained: < 0.3 (negative test); 0.3-0.6 (intermediate positivity); > 0.6 (high positivity). According to the response to treatment during the follow-up period, patients were further divided into three classes: sustained responders; relapsers or partial responders; non-responders. In each patient, the OD values were similar in the three determinations before, after therapy and at the end of the follow-up period. All patients with an intermediate positive test for anti-HCV IgM core antibodies were relapsers or partial responders, and all patients with high OD values were non-responders. Conversely, 71% of the patients with a negative test were sustained responders. We conclude that this cheap and easily performed test may be useful in predicting the response to IFN therapy.