A CLINICAL AND SEROLOGICAL COMPARISON OF FAMILIAL AND NONFAMILIAL SYSTEMIC LUPUS-ERYTHEMATOSUS IN IRELAND

Seventeen families, in which the diagnosis of SLE could be verified in two relatives, were included in the study. The diagnosis was made acc ording to the revised 1982 ARA criteria. We compared the 34 cases of f amilial SLE in these 17 families with 34 non-familial SLE controls mat ched for age, sex, ethnicity and duration of disease. Comparisons were made for the presence of 26 clinical and 11 serological features. The frequency of clinical features was similar between the groups. The fr equency of anti-Ro antibody was higher in the non-familial group (15 o ut of 34 compared to 6 out of 34, P = 0.036, McNemar's test), although this was not significant after application of Bonferoni's correction for the number of comparisons. No cases of familial IgA or familial co mplement deficiency were identified. It was noted that 10 of the 34 no n-familial patients and only one of the familial patients had the comb ination of anti-Re antibody and photosensitivity. The findings of this study support the hypothesis that familial SLE and non-familial SLE a re the same clinical entity, although there are differences in the sub types of disease.