New predictive factors of poor response to therapy in autoimmune hepatitis: role of mean platelet volume.

BACKGROUND AND OBJECTIVES: The response to immunosuppressive therapy in autoimmune hepatitis (AIH) is a matter of debate. The aim of this work is to identify the histological, biochemical, and clinical predictive factors of incomplete response/treatment failure to the standard treatment (prednisone with or without azathioprine) in a well-characterized series of AIH Egyptian patients.

PATIENTS AND METHODS: Of 49 AIH patients, only 36 patients completed this retrospective cohort study. The immunological, biochemical, histopathological, and clinical characteristics of patients were evaluated at diagnosis and during follow-up.

RESULTS: Patients were classified into two groups; group A showed a complete response to therapy (n=22; 61%) and group B showed partial response/treatment failure (n=14; 39%). In a multivariate analysis, we observed that age at diagnosis up to 22 years [odds ratio (OR): 23.22; confidence interval (CI): 3.978-135.549; P<0.001], serum albumin up to 3.2 g/dl (OR: 5.36; CI: 1.237-23.209; P=0.025), mean platelet volume (MPV) of at least 10.75 fl (OR: 16.5; CI: 3.093-88.037; P<0.001), and presence of cirrhosis at diagnosis (OR: 8.44; CI: 1.682-42.392; P=0.001) were independent variables that can predict partial response/treatment failure. MPV correlated positively with stages of fibrosis/cirrhosis and grades of activity in liver biopsy at diagnosis and correlated inversely with serum albumin and age at presentation. During therapy, group B showed a fluctuation in MPV levels, however, group A showed a progressive decline until the end point.

CONCLUSION: Our study confirmed that younger age, hypoalbuminemia, increased MPV, and cirrhosis at diagnosis were all independent predictors of incomplete response/treatment failure in AIH patients. MPV may reflect the response to therapy.