Immunoglobulins in alopecia areata.

Serum immunoglobulin levels (IgA, IgM, IgG) were measured by radial immunodiffusion in 57 subjects with varying degrees of alopecia areata. Both IgA and IgM fell with increasing severity of disease as judged by the area of scalp involved. IgM in subjects with extensive disease was significantly lower than that of an age- and sex-matched control group.