Incompatibility associated with the bite of a brown recluse spider (Loxosceles reclusa)

Abstract

Red cell samples from a patient who was suffering from massive hemolysis due to a brown reculse spider (L. reclusa) bite were reactive by indirect antiglobulin test with most ABO-compatible serum samples. Spider venom, enzymes related to those in spider venom and antisera to plasma proteins and Rh antigens were used to investigate the unusual reactivity of the patient''s cells. IgG was detected on the patient''s cells by indirect antiglobulin tests. Cells treated with brown recluse spider venom or phosphatidylcholine phosphatidyhydrolase reacted similarly. Sphingomyelinase D, which was identified in brown recluse spider venom, may be related to the unusual reactivity of the patient''s cells. Unexpected reactions were observed when venom-treated cells were tested with Rh antibodies: O negative cells absorbed and eluted anti-D from Rh immune globulin; E negative cells were reactive with a commercial anti-E reagent.