Autoimmune Hepatitis Induced after Treatment of Syphilitic Hepatitis

We present a unique case of biopsy-proven syphilitic hepatitis which presented as severe acute liver injury with significant elevation in aminotransferases and bilirubin, and improved with antibiotic therapy. However, the patient returned weeks after initial presentation with new-onset acute liver injury and had developed hypergammaglobulinemia, positive autoantibody titers, and repeat liver biopsy demonstrating interface hepatitis, supporting a diagnosis of autoimmune hepatitis. He had an otherwise unrevealing etiologic workup, and responded to glucocorticoid therapy. We believe that syphilitic hepatitis and its treatment subsequently triggered an immunogenic response, leading to autoimmune hepatitis. Autoimmune hepatitis is a chronic liver disease thought to manifest as a result of predisposing genetic factors in combination with environmental insults, especially hepatotropic pathogens. Syphilis is a sexually transmitted disease caused by Treponema pallidum that has been associated with autoimmunity and the development of autoantibodies. We propose that in the setting of syphilitic hepatitis, a molecular mimicry event resulting from structural similarities between T. pallidum and liver antigens, as well as impaired regulatory T-cell function, led to the breakdown of immune tolerance and the onset of autoimmune hepatitis. To support this hypothesis, further molecular analyses and case series are necessary to determine if syphilitic hepatitis and its treatment are risk factors for the onset of autoimmune hepatitis. Autoimmune hepatitis should be considered early as the cause of acute liver injury in susceptible patients with risk factors for the disease, as prompt recognition and appropriate treatment may prevent progression of liver injury and result in improved outcomes.