GRANULOCTYE-COLONY STIMULATING FACTOR IN THE TREATMENT OF CARBIMAZOLE-INDUCED AGRANULOCYTOSIS

Abstract

INTRODUCTION
Agranulocytosis is a rare complication of anti-thyroid treatment and may have life-threatening consequences. Current management involves timely identification of the condition and cessation of the causative drug. Supportive management and broad-spectrum antibiotics remain the mainstay of treatment. Granulocyte-colony stimulating factor (G-CSF) may also be considered. This is usually followed by definitive treatment of hyperthyroidism once the patient has recovered.

CASE
A 51-year-old gentleman with a history of thyrotoxicosis started on carbimazole 6 months ago presented with fever and odynophagia. A full blood count showed agranulocytosis with a
neutrophil count of 0.03 103/µL. He was admitted to the hospital and given filgrastim and broad-spectrum antibiotics. His counts showed improvement after 10 days and radioactive iodine treatment was subsequently planned. This gentleman showed poor response to initial filgrastim treatment and only appeared to respond subsequently after a higher filgrastim dose (600 µg).

CONCLUSION
Studies have shown mixed results in terms of reduction in haematologic recovery time after G-CSF administration. Possible explanations include the differences in doses of G-CSF used in various studies and differences in bone marrow characteristics of the treated patients. The costeffectiveness and usefulness of routine total white count monitoring in asymptomatic patients is debatable. This case illustrates the possible role of G-CSF in the management of anti-thyroid medication induced agranulocytosis although more research is required in this area. Patient education and awareness remains a major area of concern. Early education by their treating physician is essential.