Immunologic derangement in myotonic dystrophy--abnormal contact sensitization to dinitrochlorobenzene.

A broad spectrum of immunologic parameters was investigated in 13 cases of myotonic muscular dystrophy (MyD), including those for cellular immunity which has attracted little attention in the past. One was a 46-year-old woman having both MyD and a thymoma. This association between MyD and thymoma is probably coincidental without biologic significance. There was no evidence of malignancy in the remaining 12 patients. The delayed cutaneous hypersensitivity reaction to dinitrochlorobenzene was anergic in 3 patients and showed impaired positive reactivity in 3 patients, as compared with no failure of response in normal adults or children with Duchenne muscular dystrophy. A high proportion of patients with MyD displayed positive tuberculin reactions, as did controls. Our case of MyD with a thymoma showed marked lymphocytopenia in peripheral blood, but the number of lymphocytes in peripheral blood in the remaining 12 patients was normal. Uptake of tritiated thymidine by lymphocytes in the presence of phytohemagglutinin was normal. Serum gammaglobulin was reduced in 4 patients with MyD. The mean value of serum immunoglobulin level was decreased only in the class of IgG. A wider derangement of immunologic function may occur in MyD than was previously recognized.