Drug safety surveillance within a strategy for the management of non-chemotherapy drug-induced neutropenia

Drug-Induced Neutropenia During Treatment of Non-Neoplastic Dermatologic Diseases: A Review

Idiosyncratic drug-induced neutropenia (DIN) is a rare, potentially fatal adverse reaction. A literature search was performed on Pubmed and Embase, targeting articles indicating neutropenia as a complication during the treatment of non-neoplastic dermatological disorders. In 66 identified articles, the common incriminated drugs included conventional oral immunomodulators, topical cytotoxic agents, antibacterials, antifungals, biologics and targeted synthetic disease-modifying antirheumatic drugs, non-steroidal anti-inflammatory drugs, and retinoids, with dapsone being reported most often. The duration of drug exposure before the diagnosis of neutropenia varied, but mostly ranged from days to weeks. The majority of patients recovered after drug discontinuation and supportive management including antibiotics and granulocyte colony-stimulating factor, but fatal cases were reported. The proposed pathogenesis of DIN consists of direct drug toxicity and immune-mediated reaction. Certain genetic variants, individual variability in enzyme efficiency, and concomitant use of other drugs may increase the risk of DIN. Being familiar with the most commonly implicated agents and risk factors helps early identification and prompt management of this potentially fatal complication.

Idiosyncratic Drug-Induced Neutropenia and Agranulocytosis in Elderly Patients

Agranulocytosis is a rare, but serious and life-threatening hematologic disorder in elderly patients. Idiosyncratic drug-induced agranulocytosis (IDIA) has been classically defined by a neutrophil count below 0.5 × 10⁹/L. The annual incidence of IDIA in Europe is about 1.6–9.2 cases per million inhabitants. Increasing age and female sex have been considered as risk factors for the development of this condition. Besides, it is well known that older people take on average more drugs than younger people. This condition is most often associated with the intake of antibacterial agents, antiplatelets, antithyroids, antipsychotics, antiepileptics and nonsteroidal anti-inflammatory drugs (NSAIDs). Initially, agranulocytosis may present without symptoms, but may quickly progress to a severe infection and sepsis. The causative drug should be immediately stopped. In febrile patients, blood cultures and where indicated, site-specific cultures should be obtained and early treatment with empirical broad-spectrum antibiotics started. Even with adequate treatment, the mortality rate is higher in elderly patients reaching up to 20%. Hematopoietic growth factors have proven to be useful as they shorten the duration of neutropenia. However, data on neutropenia and agranulocytosis in the elderly meeting the criteria of evidence-based medicine are still poor in the literature. This review analyzes the results of our experience as well as other published studies of the universal literature.