Publication of the Week - 06/07/2024


Antithyroid Drug-Induced Agranulocytosis: A Case Report


Micaela MacKay 1, Madison C Clewis 1, Patrick Sweet 1




Agranulocytosis is a rare but life-threatening complication of methimazole and propylthiouracil, antithyroid drugs (ATDs) prescribed for the treatment of hyperthyroidism. We report the case of a 41-year-old female who presented to our institution with complaints of fevers, chills, sore throat, myalgias, and generalized weakness one month after treatment initiation with methimazole. A complete blood count at admission revealed agranulocytosis with an absolute neutrophil count of 0/μl. After discontinuation of the medication, she was treated with granulocyte-colony stimulating factor and intravenous broad-spectrum antibiotics, which improved her condition on day seven of hospitalization. Although agranulocytosis is a rare complication of antithyroid drugs, providers must maintain a high index of clinical suspicion as prompt diagnosis and treatment are essential. After the diagnosis is confirmed with an absolute neutrophil count <500/μl, management involves discontinuation of the offending agent and initiation of intravenous broad-spectrum antibiotics. Granulocyte-colony stimulating factor, commonly employed in addition to antibiotics, is a controversial treatment option and more research demonstrating its efficacy is necessitated. Preventing mortality associated with antithyroid drug-induced agranulocytosis is achieved through patient education at the time of ATD initiation. 20% lower (hazard ratio, 0.80; 95% CI, 0.67 to 0.95, P=0.01). Serious adverse events were reported in a lower percentage of participants in the semaglutide group than in the placebo group (49.6% vs. 53.8%).