Moxalactam-Associated Platelet Dysfunction

Abstract

<h3>To the Editor.—</h3> The recent article by Weitekamp and Aber (1983;249:69) called our attention to a patient who we recently saw with spontaneous lower gastrointestinal (GI) tract bleeding while he was receiving moxalactam disodium therapy. <h3>Report of a Case.—</h3> A 72-year-old man (four weeks after aortocoronary bypass surgery) experienced a spontaneous, massive lower GI tract hemorrhage on the 20th day of moxalactam disodium therapy (1 g every 12 hours) for<i>Acinetobacter calcoaceticus</i>var<i>anitratus</i>pneumonia. Sigmoidoscopy and angiography showed no focus of hemorrhage. Laboratory studies at this time disclosed the following values: prothrombin time, 10 s (reference range, 23 to 26 s); platelet count, 836,000/ cu mm (reference range, 150,000 to 400,000/cu mm); bleeding time, longer than 20 minutes (reference range, 2.5 to 9 minutes); and creatinine, 3 mg/dL (reference range, 0.8 to 1.5 mg/dL). Platelet aggregation studies demonstrated an absent second-phase wave with both 2×10^-6M adenosine diphosphate