Do plasma anti phospholipid antibodies in patients with autoimmune haemolytic anaemia correlate with reduced levels of erythrocyte complement receptor 1?

ABSTRACT

Anti phospholipid antibody (APA), of both IgG and IgM class, was assayed in plasma obtained from patients with autoimmune haemolytic anaemia (AHA) and active haemolysis. Although plasma APA was elevated in some AHA patients, when compared to a normal control population, there was no apparent correlation with levels of erythrocyte complement receptor 1 (RBC-membrane CR1) in this patient group. However, there appeared to be a correlation between RBC-membrane CR1 and plasma IgG APA in a subset of the AHA patients with low RBC-membrane CR1. The potential significance of this observation was complicated by the majority of these patients having a plasma APA within the normal range. These results suggest that the reported inverse correlation between APA and RBC-membrane CR1 may not be definitive.