Variant syndromes of autoimmune hepatitis.

The diagnostic criteria for each of the three major autoimmune liver diseases must be codified and the boundaries between diseases established. There will always be syndromes with mixed or atypical features because classically defined disorders represent only the outer ends of the diagnostic spectrum. It is only after boundaries have been decided by consensus that the true variants of autoimmune liver disease can be appreciated. Until then, both the diagnosis and treatment of these syndromes will be arbitrary and unclear.