Isolated prolongation of activated partial thromboplastin time following wasp sting

Reactions after bee or wasp sting are similar to anaphylaxis. Symptoms such as weakness, fatigue, vomiting, diarrhea, urticaria, and hypotension may occur. Serious toxic reactions usually occur after numerous stings. Massive bee envenomations can result in immediate onset of shock, hemolysis, rhabdomyolysis, disseminated intravascular coagulation (DIC), coma, and renal failure. In milder cases, patients may only have isolated prolonged activated partial thromboplastin time (aPTT) and normal prothrombin time (PT), clinically without a tendency to bleed. As a rule, they recover spontaneously without any complication. We report three cases of wasp stings; they all manifested prolongation of aPTT and finally recovered completely. Isolated prolongation of aPTT in cases of wasp stings may be related to an extract from the venom inhibiting the coagulation pathway.