This article reports the case of a patient who developed a sudden impairment of gas exchange, renal function and a distended abdomen 13 days after admission to the intensive care unit. The combination of a sudden platelet drop, the timing of heparin administration and evidence of thromboembolic events by computed tomography (CT) led to the suspected diagnosis of heparin-induced thrombocytopenia (HIT) type II which was confirmed by laboratory testing. HIT is a life-threatening complication of heparin anticoagulation and CT is an important diagnostic instrument for detecting the location and extent of thromboembolic manifestations, thereby enabling the initiation of therapy to prevent further complications.