Serum immunoglobulin levels in schizoaffective disorders (manic and depressive).

Immunoglobulin levels (A, G, M) were measured with Mancini's radial immunodiffusion technique (RID). IgA and IgG levels showed a statistically significant increase in schizoaffective patients compared to normals, and schizophrenics, but no modification in comparison with the affective patients. IgM also showed a statistically significant increase which may constitute a trait marker for the schizoaffective disease.