Efavirenz-Induced Hepatitis Mimicking Autoimmune Hepatitis: A Case Report

Efavirenz is a widely used and effective non-nucleoside reverse transcriptase inhibitor (NNRTI) for the treatment of HIV. Hepatotoxicity, although recognized, typically occurs early in the course of NNRTI therapy. However, delayed liver injury resembling autoimmune hepatitis is rare. We report a 62-year-old HIV-positive man on long-term efavirenz who developed new, asymptomatic elevations in liver enzymes after years of stable antiretroviral therapy. Work-up revealed elevated levels antinuclear antibodies (ANA) IgG after exclusion of metabolic and viral hepatitis. Although biopsy findings suggested autoimmune hepatitis, the absence of other autoimmune features and the patient's stable HIV control prompted reconsideration of the diagnosis. A multidisciplinary team suspected efavirenz-related liver injury, and the drug was replaced with Raltegravir while the rest of the antiretroviral therapy (ART) regimen was maintained. Immunosuppression was withheld to observe the biochemical response. Following Efavirenz withdrawal, liver enzymes, IgG, and ANA levels normalized, and liver stiffness on FibroScan improved. This case highlights the challenge of distinguishing autoimmune hepatitis from drug-induced liver injury when autoimmune markers are present and emphasizes the importance of considering late ART toxicity, as timely drug withdrawal can lead to full recovery without immunosuppression.