Autoimmune associations in a Mexican cohort with primary biliary cholangitis

Introduction: Several groups have reported associations of primary biliary cholangitis with other autoimmune entities, particularly Sjogren's syndrome and hypothyroidism. Its prevalence and characteristics in Mexican patients is unknown. Aim: To determine the frequency and characteristics of autoimmune diseases in a Mexican cohort of patients with primary biliary cholangitis. Materials and methods: The medical records of patients that presented with primary biliary cholangitis within the time frame of 2005 and 2012 were reviewed and assessed for other autoimmune diseases. Results: Seventy-eight patients, 75 women and 3 men, were included. Their mean age was 55.8 years. Seventy-three cases had positive antimitochondrial antibodies (94.8%) and disease was confirmed in 5 through liver biopsy. Five patients (8%) had anti-smooth muscle antibodies and 55/78 (70.5%) had antinuclear antibodies by indirect immunofluorescence. Forty-nine patients (62.8%) were positive for an autoimmune disease other than primary biliary cholangitis. Among those, 20 patients had one associated disease, 14 had 2, and 15 patients had 3 concomitant diseases. They included: Sjogren's syndrome in 23/78 patients (29.5%), dysthyroidism in 21/78 cases (26.9%), Raynaud syndrome in 11/78 (14.1%), CREST syndrome in 9/78 patients (11.4%), rheumatoid arthritis in 6/78 patients (7.7%), vitiligo in 5/78 (6.4%), scleroderma in 4/78 patients (5.1%), and other diseases in 8 patients. In 12/78 patients (15.4%), there was a documented family background of autoimmune disease. Conclusions: The presence of autoimmune associations in our cohort was frequent, and similar in characteristics to the information reported by other groups. The clinical implications of those findings remain to be determined.