Lupus in the family--analysis of a cohort followed from 1978 to 1999.

Familial lupus is recognised but rarely described in mother-daughter case pairs. We describe the prevalence of lupus occurring in the first degree relatives of a cohort of 300 lupus patients under long-term follow-up at a specialised lupus clinic. Three instances of mothers and their daughters who both developed the disease are described in detail to try and ascertain whether there are any particular clinical/serological/genetic factors in common which might explain the phenomenon.