Monocyte in vitro function in systemic lupus erythematosus (SLE). III. Bactericidal activity in presence of SLE-sera.

The bactericidal activity of normal monocytes in the presence of serum from 14 patients with SLE was studied with a modification of the Maaloe technique. The bactericidal activity was impaired in the presence of sera from 8/14 patients. The group with abnormal bacterial killing showed higher clinical activity than did the group with normal killing capacity. Corticosteroid therapy was also more common among patients with reduced killing. A further difference between patients with abnormal and normal killing was that the former had more episodes of infection during a 2-year follow-up period.