Abstract

As part of a wider survey of infections and defence mechanisms, concentrations of serum immunoglobulins IgG, IgA, and IgM were measured regularly by single radial immunodiffusion in a group of children receiving treatment for acute lymphoblastic leukaemia while in their first remission. IgM concentrations were often markedly raised at diagnosis, and IgG and IgA concentrations both began falling within one month of diagnosis. Four months after diagnosis all three had fallen significantly, but this tendency stopped after six months. Only IgG partially recovered, and non returned to pretreatment concentrations even in children followed for two years. The results suggest that vincristine and prednisone are the major factors that initiated the fall in IgG and IgA. Lowered IgM concentrations may have been due to cranial irradiation or continuous maintenance treatment, or both.