Sepsis and persisting neutropenia in a drug addict

Abstract

A 38-year-old woman was brought in to the emergency room (ER) because of altered level of consciousness. She had a known history of seizure disorder but was not on any prescription medications. She also had a history of intravenous (IV) drug abuse, including cocaine, methamphetamine, and heroin. She recently described herself as being "pill-sick" which according to her partner meant that she felt unwell after a recent administration of an illicit drug.In the ER, she was hypoxemic and was intubated. She was febrile, her blood pressure was 90 systolic, heart rate 120/min, and oxygen saturation undetectable by the digital probe. Admission hemoglobin was 11.6 g/dL (mean corpuscular volume [MCV] 86), white blood count 0.8 3 10 9 /L (absolute neutrophil count [ANC], 0.2), and platelet count 97 3 10 9 /L. Rare nucleated red blood cells were seen, but no myeloblasts or other primitive cells. Coagulation studies showed INR 3.1, activated partial thromboplastin time (aPTT) 81 s, and fibrinogen 1.9 g/L. The serum creatinine was 320 mmol/L (reference range, 50-98); serum lactate measured 13.0 mmol/L (reference range, 0.5-2.2). A chest X-ray showed multiple pulmonary infiltrates and right-sided pleural effusion. A CT head scan was negative for any acute abnormality. CT chest was suspicious for a right-sided empyema, but no vegetations were seen on the heart valves. The most striking finding on her admission blood work was leukopenia with near-absence of neutrophils in the peripheral blood. The clinical picture of hypotension, tachycardia, lactic acidosis, renal failure, pulmonary infiltrates, and pleural effusion in the setting of IV drug abuse, together with thrombocytopenia, coagulopathy, and normoblastemia, suggests septicemia in the setting of pneumonia or right-sided infective endocarditis, most likely complicated by disseminated intravascular coagulation (DIC)-although fibrin D-dimer levels would be helpful in supporting the last diagnosis. Severe sepsis can result in a transient leukopenia/neutropenia, 1 although complete absence of circulating neutrophils is unusual and points to a possible de novo neutropenic disorder such as drug-induced agranulocytosis 2,3 (although the patient was not receiving any prescription medications). Current guidelines do not recommend starting this patient on G-CSF on admission due to lack of proven mortality benefit. 4,5 Circulating nucleated red blood cells (normoblastemia) portend a poor prognosis in a critically ill patient. 6 She had a central venous catheter inserted into her right internal jugular vein and was transferred to the intensive care unit (ICU) on vasopressin and norepinephrine. Blood and urine cultures were sent and the patient was started on piperacillin-tazobactam and vancomycin. Repeat blood work showed progressive thrombocytopenia, with the platelet count measuring 9 3 10 9 /L 20 h later, and with the leukocytes and ANC remaining profoundly reduced at 0.1 and 0, respectively. Repeat coagulation studies showed INR 3.9, aPTT >150, fibrinogen 2.0, and D-dimer > 20,00...