Liver failure in an antimitochondrial antibody-positive patient with sarcoidosis: Primary biliary cirrhosis or hepatic sarcoidosis?

A 63-year-old white male with chronic liver disease diagnosed with PBC and later (after being diagnosed with pulmonary sarcoidosis) interpreted as sarcoidosis of the liver presented for evaluation for liver transplantation. The review of the patient's medical history revealed features supporting both a diagnosis of PBC (pruritus and the presence of AMAs) and sarcoidosis (liver, pulmonary, and thyroid granulomas). The specificity of the patient's AMAs for the major PBC autoantigen was confirmed by immunoblotting. He had a positive pulmonary gallium scan and his pulmonary symptoms responded to corticosteroid treatment, consistent with a diagnosis of sarcoidosis. Therefore, the patient has concomitant sarcoidosis and PBC. Although the review of his liver biopsies did not clearly differentiate between sarcoidosis- and PBC-induced damage, the independent impressions of three different experienced pathologists were one of hepatic sarcoidosis. He subsequently underwent liver transplantation and is doing well 7 years later. Overlap between these diseases is rare; it is equally rare that hepatic sarcoidosis results in a need for liver transplantation. The number of PBC/ sarcoidosis overlap cases in the United States reported in the literature and the reported prevalence of the two diseases in the United States is consistent with independent etiologies for these diseases. If an association does indeed exist, it may be obscured by the limitations in differentiating between these diseases. The expanded use of immunoblotting or ELISA to detect M2-specific autoantibodies may help clarify whether a true association exists between PBC and sarcoidosis.