17-year-old patient with neutropenia and fever during therapy with analgesics

History and admission findings: A 17-year-old patient was admitted to the hospital because of fever, shivering and odynophagia. After a pathologic fracture of the neck of the femur because of a preexisting bone cyst he had been taking a combined analgetic therapy with tilidin, metamizole and diclofenac for three weeks. Physical examination was completely normal. Investigations: The differential blood count revealed a severe neutropenia of <100/mu l and an elevated C-reactive protein. Several blood cultures were negative. Despite multiple diagnostic procedures no focus of infection could be detected. A bone marrow biopsy showed an impaired maturation of granulocyte precursor cells with a predominance of promyelocytes. Acute leukaemia could be excluded. This finding is typical for a e. g. metamizole-induced agranulocytosis. Treatment and course: Treatment consisted of reverse isolation, intravenous broad-spectrum antibiotics and granulocyte colony-stimulating factors. In the following days, the clinical condition of the patient improved considerably and the neutrophil blood count normalized. Conclusion: This case report presents the clinical course of an acute drug-induced agranulocytosis. This condition has to be considered as a rare but potentially life-threatening side effect of a variety of drugs, for example metamizole, and requires immediate treatment.