ANTIINTRINSIC FACTOR ANTIBODIES IN SYSTEMIC LUPUS-ERYTHEMATOSUS

As the co-existence of pernicious anaemia (PA) and systemic lupus eryt hematosus (SLE) has been repeatedly reported, we have investigated the presence of anti-intrinsic factor antibodies (IFAb), the immunologica l hallmark of PA, in patients diagnosed with SLE. Serum cobalamin leve ls and IFAb were determined in 30 women diagnosed with SLE as well as in 45 controls. Cobalamin levels were low in 7/30 patients. IFAb were detected in 3/30 sera from patients but in none of the control sera. T he presence of IFAb was associated with a low cobalamin concentration, anaemia and macrocytosis in only one patient. There was no evident re lationship between the presence of IFAb and serological markers of SLE . We conclude that IFAb may appear in SLE patients, although the cobal amin deficiency described in SLE seems to be due to the presence of IF Ab in only a minority of cases.