Antineutrophil Cytoplasmic Antibody-Positive Small-Vessel Vasculitis Associated with Antithyroid Drug Therapy: How Significant Is the Clinical Problem?

Abstract

BACKGROUND:

The aim of this review was to delineate the characteristics of antineutrophil cytoplasmic antibody (ANCA)-associated small-vessel vasculitis associated with antithyroid drugs (ATD). A PubMed search was made for English language articles using the search terms antithyroid drugs AND ANCA OR ANCA-associated vasculitis.

SUMMARY:

The literature includes approximately 260 case reports of ANCA-associated small-vessel vasculitis related to ATD, with 75% of these associated with thiouracil derivatives (propylthiouracil [PTU]) and 25% with methyl-mercapto-imidazole derivatives (MMI/TMZ). The prevalence of ANCA-positive cases caused by ATD varied between 4% and 64% with PTU (median 30%), and 0% and 16% with MMI/TMZ (median 6%). Young age and the duration of ATD therapy were the main factors contributing to the emergence of ANCA positivity. Before ATD therapy initiation, the prevalence of ANCA-positive patients was 0-13%. During ATD administration, 20% of patients were found to be positive for ANCA. Only 15% of ANCA-positive patients treated with ATD exhibited clinical evidence of vasculitis, corresponding to 3% of all patients who received ATD. Clinical manifestations of ANCA-associated vasculitis related to ATD were extremely heterogeneous. When vasculitis occurred, ATD withdrawal was usually followed by rapid clinical improvement and a favorable prognosis.

CONCLUSIONS:

ANCA screening is not systematically recommended for individuals on ATD therapy, particularly given the decreasing use of PTU in favor of TMZ/MMI. Particular attention should be given to the pediatric population with Graves' disease who receive ATD, as well as patients treated with thiouracil derivatives and those on long-term ATD therapy.

• Authors: Anne-Sophie Balavoine, Daniel Glinoer, Sylvain Dubucquoi, Jean-Louis Wémeau
• Journal: Thyroid : official journal of the American Thyroid Association (Thyroid) Vol. 25 Issue 12 Pg. 1273-81 (Dec 2015) ISSN: 1557-9077 [Electronic] United States
• PMID: 26414658 (Publication Type: Journal Article, Review)

Chemical References

• Antithyroid Agents
• Methimazole
• Propylthiouracil

Topics

• Age Factors
• Anti-Neutrophil Cytoplasmic Antibody-Associated Vasculitis (epidemiology)
• Antithyroid Agents (therapeutic use)
• Humans
• Hyperthyroidism (drug therapy)
• Methimazole (therapeutic use)
• Prevalence
• Propylthiouracil (therapeutic use)
• Time Factors