Agranulocytosis

Agranulocytosis is an acute, severe hematologic emergency characterized by a profound deficiency of neutrophils, defined strictly as an Absolute Neutrophil Count (ANC) less than 100 cells per microliter of blood. This condition, predominantly acquired and often idiosyncratic in adults (up to 70% of cases are drug-related), renders the patient extremely susceptible to life-threatening bacterial and fungal infections. The primary source of morbidity and mortality is overwhelming sepsis. Pathogenetically, agranulocytosis results from either immune-mediated destruction of circulating neutrophils or direct toxic suppression/maturation arrest of myeloid precursors in the bone marrow. Definitive management demands the immediate cessation of the suspected causative agent, prompt collection of microbiological cultures, and rapid initiation of empirical intravenous broad-spectrum anti-pseudomonal antibiotic therapy. Granulocyte Colony-Stimulating Factor (G-CSF) is typically utilized in high-risk patients to accelerate neutrophil recovery, thereby mitigating the risk of fatal infection.