Primary Biliary Cholangitis Diagnosed During Follow-Up of a Man with HIV Infection and Syphilis: A Case Report

Abstract

Background In people living with HIV, syphilis may present atypically and can involve the liver, making the etiology of liver injury difficult to determine. Primary biliary cholangitis (PBC), an autoimmune cholestatic liver disease, has rarely been reported in patients with HIV infection. Case Presentation A 34-year-old man was admitted in November 2024 with newly diagnosed HIV infection. Laboratory testing showed a viral load of 666,642 copies/mL, a CD4+ T cell count of 99 cells/μL (CD4 percentage, 4.31%), and positive syphilis serology with a TRUST titer >1:256. He also had liver dysfunction and a right hepatic lesion. Initial liver biopsy suggested severe infection-related liver injury with bile duct damage. However, a syphilitic etiology remained presumptive. After antiretroviral therapy, anti-syphilitic treatment, and supportive care, liver enzymes normalized and the hepatic lesion regressed markedly. Antinuclear and antimitochondrial antibodies, both negative at baseline, became positive during follow-up. Repeat liver biopsy performed in August 2025, approximately nine months after the initial admission, confirmed PBC stage 1–2, ursodeoxycholic acid therapy was initiated after the diagnosis was established. Conclusion In HIV-infected patients with active syphilis and liver dysfunction, abnormalities should not be attributed to infection alone. Syphilis-associated liver injury in this case remained presumptive. Recognition of PBC during immune recovery after ART suggests a possible association, not proof of causation by syphilis or immune reconstitution. Dynamic follow-up, autoantibody monitoring, and repeat liver biopsy when clinically indicated may help identify coexisting autoimmune liver disease.