Serum Immunoglobulin Levels in Chronic Lymphatic Leukaemia

Serum immunoglobulin levels were measured in 44 patients with chronic lymphatic leukaemia and in a control group of comparable age, race, and sex. Application of two‐sided rank sum tests revealed highly significant reductions of IgG, IgA and IgM in male patients and of IgA in female patients. Slight but insignificant decreases in IgG and IgM were found in female patients. Therefore, these reductions in serum immunoglobulin levels in chronic lymphatic leukaemia are probably attributable to the disease state per se and not to the known variables of age, race, and sex. The potential usefulness of multivariate linear discriminant functions derived from the immunoglobulin levels of the control and patient populations is discussed.