New-onset Systemic Lupus Erythematosus after Methimazole Exposure Followed by Autoantibody Emergence
Abstract
Methimazole-associated new-onset systemic lupus erythematosus (SLE) is rare and it may be difficult to distinguish from classic drug-induced lupus. We report a 19-year-old man who developed fever, polyarthralgia, rash, and ocular pain three months after initiating methimazole for Graves' disease. At symptom onset, antinuclear antibodies and ANCA were negative, and there was no hypocomplementemia. Despite methimazole withdrawal, inflammation persisted. During the subsequent clinical course, ANA and MPO-ANCA became positive, in conjunction with the emergence of anti-double-stranded DNA antibody and hypocomplementemia, thus fulfilling the classification criteria for SLE. Early seronegativity does not exclude evolving SLE and represents an important diagnostic pitfall. Clinicians should be aware that MPO-ANCA positivity may further complicate the differential diagnosis in such cases.
Related
- Clinical Phenotype, Treatment Exposure, Treat-to-Target Status, and Longitudinal Outcomes in Juvenile-Onset Systemic Lupus Erythematosus: A Single-Center Retrospective Cohort Study
- Comparison Between Systemic Lupus Erythematosus Patients with and Without Family History of Systemic Lupus Erythematosus—A Single-Center Retrospective Study
- Germinal center and extrafollicular dysregulation in systemic lupus erythematosus: Mechanisms and therapeutic opportunities
- Recurrent Pericarditis With Cardiac Tamponade in a Patient With Systemic Lupus Erythematosus: A Case Report
- Case report: Incidental finding of a duplicated right vertebral artery in a 17-year-old female with suspected systemic lupus erythematosus
BibTeX
@article{ishida2026newonset,
title = {{New-onset Systemic Lupus Erythematosus after Methimazole Exposure Followed by Autoantibody Emergence}},
author = {Ayaka Ishida and Ryoko Asano and Satoshi Yamaguchi and Ikuma Okada and Miho Yamazaki and Naonori Sugishita and Masatoshi Kawataka and Toshiki Kido and Hiroyuki Hounoki and Masaru Kato},
journal = {Internal Medicine},
year = {2026},
month = jul,
doi = {10.2169/internalmedicine.7691-26},
url = {https://www.jstage.jst.go.jp/article/internalmedicine/advpub/0/advpub_7691-26/_article},
note = {CC BY-NC-ND},
}
RIS
TY - JOUR
TI - New-onset Systemic Lupus Erythematosus after Methimazole Exposure Followed by Autoantibody Emergence
AU - Ayaka Ishida
AU - Ryoko Asano
AU - Satoshi Yamaguchi
AU - Ikuma Okada
AU - Miho Yamazaki
AU - Naonori Sugishita
AU - Masatoshi Kawataka
AU - Toshiki Kido
AU - Hiroyuki Hounoki
AU - Masaru Kato
PY - 2026
DA - 2026/07/11
JO - Internal Medicine
DO - 10.2169/internalmedicine.7691-26
UR - https://www.jstage.jst.go.jp/article/internalmedicine/advpub/0/advpub_7691-26/_article
AB - Methimazole-associated new-onset systemic lupus erythematosus (SLE) is rare and it may be difficult to distinguish from classic drug-induced lupus. We report a 19-year-old man who developed fever, polyarthralgia, rash, and ocular pain three months after initiating methimazole for Graves' disease. At symptom onset, antinuclear antibodies and ANCA were negative, and there was no hypocomplementemia. Despite methimazole withdrawal, inflammation persisted. During the subsequent clinical course, ANA and MPO-ANCA became positive, in conjunction with the emergence of anti-double-stranded DNA antibody and hypocomplementemia, thus fulfilling the classification criteria for SLE. Early seronegativity does not exclude evolving SLE and represents an important diagnostic pitfall. Clinicians should be aware that MPO-ANCA positivity may further complicate the differential diagnosis in such cases.
SN - 1349-7235
SN - 0918-2918
ER -