Autoimmune hepatitis in Singapore: a rare syndrome affecting middle-aged women

BACKGROUND AND AIM: The prevalence of autoimmune hepatitis in Singapore is unknown. Over a period of 7 years, 24 cases were diagnosed in a district general hospital in Singapore (Toa Payoh Hospital) by using the scoring system proposed by the International Autoimmune Hepatitis Group in 1993. The aims of our study were to determine the prevalence of autoimmune hepatitis in Singapore, and to investigate the characteristics and prognosis in the mainly Chinese population. METHODS: The case records of all 24 patients were reviewed, and the following parameters were recorded: age at presentation, sex, symptoms and signs at presentation, past exposure to hepatotoxic drugs, alcohol intake, blood transfusion laboratory and histological tests used to determine autoimmune hepatitis, response to treatment, complications, and survival. RESULTS: The mean age of patients was 57 years old. There was a female-male ratio of 11:1. Forty-two percent of the patients were cirrhotic at presentation. The prevalence of autoimmune hepatitis was four per 100 000, with no significant difference between Chinese, Malay and Indian patients (Odds ratio of 0.38 by the chi-squared test). Eighty-nine percent of the patients responded to treatment with the induction of prednisolone, but the relapse rate was 61%. Treatment failure occurred in one patient. The mortality rate during the 7 years of follow up was 21%, and all were caused by complications of cirrhosis. The survival at 5 years was 71%, with a standard error of 0.13. CONCLUSION: Autoimmune hepatitis in Singapore is mainly a disease in older women. The response to steroid treatment is good, with a 5-year survival rate of 71%.