Antithyroid Drug-Induced Agranulocytosis: A Case Report.

Abstract

Agranulocytosis is a rare but life-threatening complication ofmethimazole 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 offevers, chills, sore throat, myalgias, and generalized weakness one monthafter treatment initiation withmethimazole. 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 suspicionas 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 optionand 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.