BLACK AND BROWN WIDOW SPIDER BITES IN SOUTH-AFRICA - A SERIES OF 45 CASES

Cases of black widow (Latrodectus indistinctus) and brown widow (L. ge ometricus) spider bites referred to the Tygerberg Pharmacology and Tox icology Consultation Centre from the summer of 1987/88 to the summer o f 1991/92 were entered into this series. Of a total of 45 patients, 30 had been bitten by black and 15 by brown widow spiders. It was eviden t that black widow spider bites caused a more severe form of envenomat ion than brown widow bites, characterised by generalised muscle pain a nd cramps, abdominal muscle rigidity, profuse sweating, raised blood p ressure and tachycardia. The symptoms and signs of brown widow bites w ere mild and tended to be restricted to the bite site and surrounding tissues. Conditions which should be considered in the differential dia gnosis include cytotoxic spider bite, scorpion sting, snakebite, acute abdominal conditions, myocardial infarction, alcohol withdrawal and o rganophospate poisoning. To prevent the development of complications, the administration of black widow spider antivenom is recommended in s evere cases because untreated latrodectism could become protracted, wi thout improvement, for several days.