2311 Syphilis Hepatitis Presenting as a Mimic of Primary Biliary Cholangitis

Abstract

INTRODUCTION: Primary Biliary Cholangitis (PBC) is a progressive cholestatic liver disease defined by autoimmune destruction of intrahepatic bile ducts. Patients typically present with a cholestatic liver injury pattern. Anti-mitochondrial antibody (AMA) is present in 95% of PBC diagnoses thus, an AMA titer of 1:40 in addition to alkaline phosphatase (ALP) greater than 1.5 times the upper limit of normal is diagnostic of PBC (1). Syphilis is a sexually transmitted infectious disease caused by transmission of Treponema pallidum. The highest risk populations are men who have sex with men (MSM) and persons living with HIV. Syphilis has been further associated with HIV infection considering shared risk factors and transmission routes. While the staged progression of syphilis is well-documented, not all presentations are readily observed by clinicians considering the variability of the disease. One variation that is sparingly seen is syphilis presenting as acute hepatitis. CASE DESCRIPTION/METHODS: A 54 year-old man living with HIV presented to University of Kentucky Hospital with one week of abdominal pain, vomiting, and a diffuse non-pruritic rash. Upon admission he was noted to have a cholestatic liver injury pattern. Laboratory evaluation revealed AST 91, ALT 120, ALP 832, total bilirubin 6.4, and CD4 count 336. The acute hepatitis panel was negative. Abdominal CT and ultrasound failed to demonstrate biliary ductal dilation. Further investigation revealed an RPR titer 1:256 and an anti-mitochondrial M2 antibody IgG of 83.5U. The patient was treated for syphilis with doxycycline due an allergy to penicillin. Subsequently there was complete resolution of the cholestatic liver injury and a final diagnosis of syphilis hepatitis. DISCUSSION: In this report, we present a case of syphilis that presented similar to PBC with a consistent serologic pattern and a positive AMA. Other reports have recognized syphilis as a reversible cause of cholestatic liver injury. One study in particular, recognized a high false positive AMA rate in patients with syphilis (2). As, syphilis is a easily targeted cause of liver injury, we suggest testing high-risk patients with a presumed diagnosis of PBC.