AUTOANTIBODIES RELATED TO TREATMENT WITH CHLORTHALIDONE AND α‐METHYLDOPA

. Sera from 96 hypertensive patients and an equal number of matched controls have been studied for autoantibodies. Significantly higher frequencies were found of antibodies to gastric parietal cells (14%) and antinuclear factors (A.N.F.) (14%). The direct anti-human globulin (A.H.G.) test was positive in 5% of the hypertensive patients. No increase was found in the incidence of other autoantibodies. The occurrence of A.N.F. appeared to be related to treatment with chlorthalidone, and the incidence of a positive direct A.H.G. test to α-methyldopa therapy. A possible combined effect of these drugs on serological aberrations was observed. These aberrations appeared to be unrelated to the possible cause and severity of hypertension and to age and sex. No relation was found between treatment and antibodies to gastric parietal cells.