Year: 2025
Type: article
Study design: Case Report
Abstract: Hydroxychloroquine (HCQ) is often used in sarcoidosis as a steroid-sparing agent. Though generally safe, rare cardiac side effects like bradycardia can occur, especially in patients with underlying cardiac vulnerability. A 40-year-old South Asian male with biopsy-proven sarcoidosis, stable on HCQ, azathioprine, and prednisolone, presented with low-grade fever, vomiting, and diarrhea. He was febrile, but hemodynamically stable. Labs showed leukocytosis, elevated CRP, and prerenal acute kidney injury. IV hydrocortisone was started, after which he developed sudden asymptomatic bradycardia (30-40 bpm). ECG revealed sinus bradycardia with partial right bundle branch block. Cardiac enzymes and echocardiogram were normal. Despite switching to methylprednisolone, bradycardia persisted. Given the temporal correlation and exclusion of other causes, HCQ-induced bradycardia was suspected. HCQ was discontinued, and the heart rate normalized within 48 h. This case highlights the rare risk of HCQ-induced bradycardia, which can unmask or worsen occult cardiac sarcoidosis, even after long-term therapy. Clinicians should maintain vigilance for conduction abnormalities in sarcoidosis patients receiving HCQ, particularly when immunosuppressive regimens are modified.
Source: Clinical Case Reports
DOI: 10.1002/ccr3.70986
Authors: Sana Rasheed, Umaima Aijaz, Syeda Sakina Batool Naqvi, Ahmed Asad Raza, Abedin Samadi
Language: English
Subfield: Physiology
Field: Medicine
Domain: Health Sciences
Open Access status: gold
Estimated APC paid: $1,820
OpenAlex ID: W4414550368