Hepatitis B and Essential Mixed Cryoglobulinemia

To the Editor: The report by Levo et al.¹ of an association between hepatitis B virus (HBV) and essential mixed cryoglobulinemia (EMC) describes yet another immune-complex-mediated illness related to hepatitis B. Several questions are raised by this study, however. In the first place, unless the group of patients with EMC is compared to a control group matched for such factors as age, sex, socioeconomic status, number of transfusions, number and frequency of hospitalizations and frequency of immunosuppressive therapy, it is possible that one or more of these confounding variables was responsible for the high prevalence of HBV serologic markers.