First use of G-CSF in chlorpromazine-induced agranulocytosis: a report of two cases

Non-chemotherapy drug-induced agranulocytosis

Acute agranulocytosis is a rare, potentially life-threatening condition, which is attributable to drugs in > 70% of cases. Agranulocytosis is characterised by a peripheral neutrophil count < 0.5 x 10(9)/l. It often manifests with a severe sore throat, but isolated fever, pneumonia or septicaemia are not uncommon. Agranulocytosis may be caused by many drugs. High-risk drugs include antithyroid drugs, clozapine, ticlopidine, sulfasalazine, dipyrone, trimethoprim/sulfamethoxazole, carbamazepine and probably rituximab. Suspect drugs should be stopped immediately. In febrile patients, blood cultures and, where indicated, site-specific cultures should be obtained and treatment with empirical broad spectrum antibiotics started. Haematopoietic growth factors should be considered in patients with poor prognostic factors (e.g., a neutrophil count < 0.1 x 10(9)/l), severe clinical infection or severe underlying disease or comorbidity. Case fatality has decreased to ~ 5% in recent years, probably owing to improved intensive care treatment and increased alertness of physicians to this severe adverse reaction.

Nonchemotherapy drug-induced agranulocytosis: a review of 118 patients treated with colony-stimulating factors

To determine the role of growth factors in nonchemotherapy drug-induced agranulocytosis, we reviewed 118 published reports of administration of colony-stimulating factors for the disorder. Main outcomes were total duration of neutropenia and mortality. The mean time to neutrophil recovery was 4.6 +/- 3.2 days and 7.7 +/- 5.1 days in patients with a granulocyte count at diagnosis of 0.1-0.5 x 10(3)/mm3 and less than 0.1 x 103/mm3, respectively. The mortality rate was 4.2%. Without therapy with growth factors, the mean time to neutrophil recovery after discontinuation of the offending agent was reported to be 10 +/- 8 days. The mortality rate was 16% in one study. We conclude that hematopoietic growth factors may shorten the duration of neutropenia and reduce mortality in patients with severe drug-induced agranulocytosis.

Idiosyncratic drug-induced haematological abnormalities. Incidence, pathogenesis, management and avoidance

Haematological dyscrasias remain important because they are potentially fatal. Their accurate reporting is required to confirm the cause-effect relationship of suspected adverse drug reactions (ADRs); to estimate their incidence; and, by risk-benefit analysis of such events, to introduce preventive measures to reduce their impact. Limitations within the available data on haematological ADRs are reviewed and some suggestions made for improvement. The drugs most commonly associated with haematological dyscrasias are listed. An understanding of the pathogenesis of haematological dyscrasias is essential for their effective management and these are briefly reviewed. Features common to the management of the different types of haematological dyscrasia include the early involvement of a haematologist and drug information pharmacist and the accurate identification and early withdrawal of any likely offending agent. Guidelines for the management of drug-induced aplastic anaemia, agranulocytosis, thrombocytopenia and haemolytic anaemia are presented and the potential value of granulocyte and granulocyte-macrophage colony-stimulating factors (G-CSF; GM-CSF) in the management of agranulocytosis is specifically mentioned. Finally, general principles are discussed whereby serious haematological ADRs might be prevented. These include: the importance of continuing education for drug prescribers; policies on the restricted prescribing of likely offending agents; the use of written instructions for patients; and, the use of haematological monitoring. The guidelines presented in this article should be adapted to meet local circumstances and would prove suitable subjects for audit of their effectiveness.