[Fatal necrotizing fasciitis due to Serratia marcescens]

An 81 year old female patient with chronic heart failure and atrial fibrillation receiving anticoagulant therapy, was admitted with progressive pain on her right leg for the past 24 hours, associated to local erythema, edema and warmth. The lesion evolved at the same site where she presented a chronic ulcer for the previous 5 months managed only with local care. At admission a necrotic plaque on the affected site was perceived; there was no hypotension or mental confusion but signs of a deep venous thrombosis on the involved leg were found. She was febrile (37.8 degrees C) and with tachychardia (126 per minute). Laboratory evaluation revealed normal white blood cell count and a subtherapheutic anticoagulant INR value. A chest x-ray showed infiltrates on the left lower lung lobe. On the following hours the lesion evolved with increasing pain, haemorrhagic bullae and a purulent discharge through the ulcer, with the patient developing mental deterioration, hypotension, respiratory failure and shock. The patient received intravenous ciprofloxacin and clindamycin and was operated 15 hours after admission performing an over-the knee amputation. A cardiac catheterization demonstrated a low cardiac output (2.3 L/min), and both a high systemic vascular resistance (2888 din.s.cm(-5)) and pulmonary capillary wedge pressure (17 cm H(2)0), results compatible with cardiogenic shock. Evolution was progressively worse and she died of multiple organic failure 36 hours after admission. Two blood culture samples grew Serratia marcescens. No necropsy was performed and cultures taken from the leg remained negative.