Isoniazid-Induced Systemic Lupus Erythematosus: A Case Report

Area of Science:

• Pharmacology
• Immunology
• Infectious Diseases

Background:

• Systemic lupus erythematosus (SLE) is an autoimmune disease with various known drug-induced causes.
• Tuberculosis treatment regimens may include medications with potential side effects.
• Drug-induced SLE presents a diagnostic challenge, especially when overlapping symptoms occur.

Purpose of the Study:

• To report a case of drug-induced systemic lupus erythematosus (SLE) potentially caused by isoniazid.
• To highlight the diagnostic considerations for SLE in patients undergoing tuberculosis treatment.
• To assess the causality of isoniazid in the development of SLE.

Main Methods:

• A patient diagnosed with tuberculous meningitis received antituberculosis treatment.
• Clinical presentation, laboratory investigations (including antinuclear antibody levels), and drug history were reviewed.
• Causality assessment was performed using WHO-UMC and Naranjo's criteria.
• Severity was graded using the modified Hartwig and Siegel scale.

Main Results:

• The patient developed symptoms suggestive of SLE despite antituberculosis treatment.
• Elevated antinuclear antibody levels confirmed autoimmune activity.
• Discontinuation of isoniazid led to significant clinical improvement.
• Isoniazid was identified as the probable causative agent for drug-induced SLE (WHO-UMC and Naranjo's criteria).
• The reaction was classified as moderately severe (level 4b).

Conclusions:

• Isoniazid can induce systemic lupus erythematosus (SLE).
• Early recognition and withdrawal of the offending drug are crucial for patient recovery.
• This case underscores the importance of considering drug-induced SLE in patients with unexplained autoimmune symptoms during medication therapy.