Azithromycin-related agranulocytosis in an elderly man with acute otitis media

Non-chemotherapy drugs inducing agranulocytosis: a disproportionality analysis based on the FAERS database

Introduction

Non-chemotherapy drug-induced agranulocytosis (NCDIA) is a serious adverse reaction that significantly increases the risk of life-threatening infections. Although the association between certain non-chemotherapy drugs and agranulocytosis has been documented, a comprehensive analysis using a large-scale pharmacovigilance database is lacking. This study aimed to systematically identify and characterize NCDIA by analyzing adverse event reports from the FAERS database.

Methods

We conducted a retrospective analysis of NCDIA reports from the FAERS database spanning from 2004 to 2024 Q1. Drugs were classified using the Anatomical Therapeutic Chemical (ATC) classification system, with chemotherapy agents (ATC code L01) excluded. The Reporting Odds Ratio (ROR) method was employed to detect potential adverse event signals. Positive signals were defined as cases with at least three reports and a lower 95% confidence interval (CI) of ROR greater than one. Time-to-event analysis was also performed to examine onset patterns across different demographic groups and drugs.

Results

A total of 10,913 NCDIA reports were identified from the FAERS database. Disproportionality analysis revealed significant signals for 166 non-chemotherapy drugs related to agranulocytosis, which were systematically classified into three risk categories: known (n = 111), possible (n = 25), and new potential risks (n = 30). This classification system enables us to identify drugs with known risks, those that might pose a risk, and new risks warranting further investigation. Demographic analysis revealed that females, children (<18 years), and the elderly (≥65 years) experienced earlier onset of agranulocytosis. Drug-specific onset timing analysis provided evidence for optimizing monitoring protocols. Notably, NCDIA-associated mortality rates showed a significant decrease from 11.91% (2004-2010) to 7.28% (2021-2024) (P < 0.001).

Conclusion

This comprehensive pharmacovigilance study not only confirmed previously known NCDIA associations but also identified new potential risk drugs. The novel risk classification system and detailed onset timing analysis provide valuable insights for clinical monitoring. The findings of earlier onset in specific populations and declining mortality trends have important implications for developing targeted surveillance strategies and improving patient safety management.

Febrile neutropenia due to COVID-19 in an immunocompetent patient

While lymphopenia has been a common finding in COVID-19 infection, particularly in severe cases, febrile neutropenia has been very rarely reported in immunocompetent patients with COVID-19. Herein, we report the case of a 76-year-old hypertensive and diabetic man who was hospitalised with severe COVID-19 infection and developed delayed-onset severe neutropenia with neutropenic fever, which responded to treatment with antibiotics and granulocyte colony-stimulating factor. This case highlights the importance of identifying a rare complication (febrile neutropenia on the fifth week) of COVID-19 infection in hospitalised patients by intensive monitoring and aggressive management for favourable outcomes.

Febrile neutropenia due to COVID-19 in an immunocompetent patient

While lymphopenia has been a common finding in COVID-19 infection, particularly in severe cases, febrile neutropenia has been very rarely reported in immunocompetent patients with COVID-19. Herein, we report the case of a 76-year-old hypertensive and diabetic man who was hospitalised with severe COVID-19 infection and developed delayed-onset severe neutropenia with neutropenic fever, which responded to treatment with antibiotics and granulocyte colony-stimulating factor. This case highlights the importance of identifying a rare complication (febrile neutropenia on the fifth week) of COVID-19 infection in hospitalised patients by intensive monitoring and aggressive management for favourable outcomes.

Pure White Cell Aplasia and Necrotizing Myositis

Pure white cell aplasia (PWCA) is a rare hematologic disorder characterized by the absence of neutrophil lineages in the bone marrow with intact megakaryopoiesis and erythropoiesis. PWCA has been associated with autoimmune, drug-induced, and viral exposures. Here, we report a case of a 74-year-old female who presented with severe proximal weakness without pain and was found to have PWCA with nonspecific inflammatory necrotizing myositis and acute liver injury on biopsies. These findings were associated with a recent course of azithromycin and her daily use of a statin. Myositis improved on prednisone but PWCA persisted. With intravenous immunoglobulin and granulocyte-colony stimulating factor therapies, her symptoms and neutrophil counts improved and were sustained for months.

Azithromycin-induced agitation and choreoathetosis

We report a child who developed agitation and choreoathetoid movements with azithromycin therapy on 2 separate occasions. In both instances, the symptoms resolved when the antibiotic was discontinued. By means of the Naranjo adverse drug reaction probability scale, we classified this event as a probable adverse drug reaction (score of 6 points). To our knowledge, this is the first published case of azithromycin-induced agitation with choreoathetosis. Because this is a widely used medication for many common infectious conditions, including otitis media and pneumonia, this potential serious adverse reaction should be considered.