Life-threatening idiosyncratic drug-induced agranulocytosis in elderly patients

Agranulocytosis is a life-threatening disorder in any age, but particularly so in elderly patients who are receiving, on average, a larger number of drugs than younger patients. Drug-induced agranulocytosis still remains a rare event, with an annual incidence rate of approximately 3-12 cases per million population. This disorder frequently occurs as an adverse reaction to drugs, particularly antibacterials, antiplatelet agents, antithyroid drugs, antipsychotics or antiepileptic drugs, and NSAIDs. Although patients experiencing drug-induced agranulocytosis may initially be asymptomatic, the severity of the neutropenia usually translates into the onset of severe sepsis that requires intravenous broad-spectrum antibacterial therapy. In this setting, haematopoietic growth factors have been shown to shorten the duration of neutropenia. Thus, with appropriate management, the mortality rate of idiosyncratic drug-induced agranulocytosis is now 5-10%. However, given the increased life expectancy and subsequent longer exposure to drugs, as well as the development of new agents, physicians should be aware of this complication and its management.