I was diagnosed with autoimmune hepatitis but they did not do a liver biopsy. should i insist on one?

You can see a liver specialist. If the diagnosis was made without a liver biopsy, you likely don’t need one. You likely had blood work done that showed this diagnosis. But, a liver specialist could be certain that you have been diagnosed correctly and guide your treatment. A biopsy can be done if the liver specialist thinks it is necessary. Good luck!

A good diagnostic algorithm can be found at my.clevelandclinic.org in which a liver biopsy is to be considered, agree with previous answer that a gastroenterologist specializing in liver diseases or a hepatologist would be best to weigh in and coordinate in case a biopsy would still prove useful to confirm diagnosis and assess for severity.