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Updated: May 25, 2026
11:49
Trans-vivo Delayed Type Hypersensitivity Assay for Antigen Specific Regulation
Published on: May 2, 2013
Delayed anithyroid drug-induced agranulocytosis
Priscilla Mutharasan1, Wendy Oatis, Hau Kwaan
1Division of Endocrinology, Metabolism, and Molecular Medicine, Department of Medicine, Northwestern University Feinberg School of Medicine, 645 North Michigan Avenue, Suite 530, Chicago, IL 60611, USA.
Summary
Drug-induced agranulocytosis can occur after prolonged low-dose antithyroid drug treatment. Vigilance for neutropenia is crucial even after years of therapy with medications like methimazole.
Area of Science:
- Endocrinology
- Hematology
Background:
- Antithyroid drugs are standard treatment for Graves disease.
- Drug-induced agranulocytosis is a rare but serious side effect.
Observation:
- A patient with Graves disease developed agranulocytosis after 11 years of continuous low-dose antithyroid medication.
- Neutrophil count dropped to zero despite stable, low methimazole dosage for one year prior.
Findings:
- Hematologic evaluation, including bone marrow biopsy, excluded other causes of agranulocytosis.
- Discontinuation of methimazole and granulocyte colony-stimulating factor led to successful recovery.
Implications:
- Highlights the risk of late-onset agranulocytosis with antithyroid drugs.
- Emphasizes the need for ongoing monitoring for neutropenia, irrespective of treatment duration or dose.
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