Systemic lupus erythematosus (SLE) induced by quinidine

Area of Science:

• Rheumatology
• Clinical Pharmacology
• Drug-Induced Diseases

Background:

• Systemic lupus erythematosus (SLE) is a chronic autoimmune disease.
• Drug-induced lupus erythematosus (DILE) is a recognized phenomenon.
• Quinidine's potential to induce SLE-like symptoms was previously rarely documented.

Observation:

• Five patients presented with an SLE-like syndrome during quinidine therapy.
• Clinical manifestations included typical SLE signs, symptoms, and laboratory abnormalities.
• No recurrence of symptoms was observed after steroid withdrawal.

Findings:

• Quinidine administration was temporally associated with the development of an SLE-like syndrome.
• Discontinuation of quinidine led to symptom improvement.
• Prednisone therapy further resolved the observed clinical and laboratory abnormalities.

Implications:

• Quinidine should be considered a potential cause of drug-induced lupus erythematosus.
• Clinicians should be vigilant for SLE-like symptoms in patients taking quinidine.
• Further research into the mechanisms of quinidine-induced autoimmunity is warranted.