Incidence and Clinical Features of Autoimmune Hepatitis in the Province of Santa Fe (Argentina).

OBJETIVES: The aim of the study is to investigate the incidence and clinical features of autoimmune hepatitis (AIH) in children from the province of Santa Fe, Argentina, for 10 years.

METHODS

From the records of all of the pediatric hepatologists in the province of Santa Fe, Argentina, we reviewed the clinical charts of patients <18 years who were diagnosed with AIH (simplified score >6 points) and followed between January 2003 and December 2013. Population data were extracted from the 2010 national census. Values were expressed as percentages and median ± interquartile range. Mann-Whitney U test was used for comparison between the groups.

RESULTS

Sixty-seven patients fulfilled inclusion criteria, from which 11 (16%) were later reclassified as having "autoimmune sclerosing cholangitis" according to biochemical, histological, and radiological findings. A final sample of 56 patients (39 F) with AIH was analyzed, giving an annual incidence of 0.56/100,000. Median age at presentation was 8 (5.7-11) years, and the median follow-up was 4 (2-7) years. Type 1 AIH was diagnosed in 89%. An acute presentation was observed in 53%, while 13 (23%) showed cirrhosis on initial biopsy. Prednisone (87%) and azathioprine (60%) were the most common drugs prescribed. At the end of follow-up, 53/56 (95%) were alive, including 4 patients (7%) who underwent liver transplantation.

CONCLUSIONS

AIH has an estimated incidence of 0.56/100,000 per year in children from the province of Santa Fe (Argentina). Overall survival rate was 95%. A subgroup of patients diagnosed as AIH develops predominant biliary disease and should be better classified as autoimmune sclerosing cholangitis.