Beta-lactam-induced severe neutropaenia: a descriptive study.

The objectives of this study were to describe the characteristics and natural history of beta-lactam-induced severe neutropaenia and to evaluate the risk of recurrences after another beta-lactam readministration. Reports of pure agranulocytosis associated with a beta-lactam exposure within the 10 days preceding the neutropaenia were extracted from the French Pharmacovigilance Database over the year 2010. Cases with another evident cause or more likely attributable to another drug were excluded. Data were analyzed for demographics, clinical and biological features, prognosis factors, granulocyte colony stimulating factors administration and outcome. Sixty-two cases were included (median age: 65 years). The median duration of treatment before neutropaenia was 16 days. In 47% of cases, the diagnosis was made on a systematic blood cell count. The median neutrophil count at nadir was 0.125 × 10 /L, and bone marrow examination evidenced features of neutrophilic maturation arrest or aplasia in 21 patients, hyperplasia of granulopoietic cells in three and normal findings in five. Three patients developed severe sepsis. All but one recovered a normal blood cell count within 2-56 days after beta-lactam discontinuation. The last patient died from recurrent severe septic shock. No significant effect of granulocyte colony stimulating factor on the mean duration of haematological recovery was found. Among the 21 patients who later received another beta-lactam, two experienced recurrence of the neutropaenia after receiving a beta-lactam from another subfamily. Beta-lactam-induced agranulocytosis was usually observed after prolonged treatment, and severe complications are uncommon. In most patients, a subsequent treatment with another beta-lactam was well tolerated.