Primary Biliary Cholangitis in a Patient With Multiple Sclerosis: A Case Report

Multiple sclerosis (MS) is a chronic autoimmune condition characterized by central nervous system demyelination. Its coexistence with primary biliary cholangitis (PBC), another autoimmune disease, is rarely described in the literature. This is the case of a 35-year-old Emirati female patient with a history of PBC who presented with unsteady gait and neurological symptoms. Neurological examination revealed dysmetria, wide-based gait, and brisk reflexes. MRI findings confirmed MS, and she was treated with methylprednisolone and disease-modifying therapies. MS and PBC share immune dysregulation, involving genetic loci like CD28 and T-cell-mediated mechanisms. Their coexistence complicates diagnosis due to overlapping symptoms such as fatigue and neurological impairment. While rare, concurrent autoimmune diseases in MS patients may influence disease progression and disability outcomes. This case emphasizes the need for multidisciplinary care in managing coexisting autoimmune diseases and for further research regarding the shared mechanisms of these coexisting autoimmune diseases.