The clinical and histologic presentation of autoimmune hepatitis (AIH) can be quite variable. Here, we present the microscopic features of AIH and discuss clinicopathologic findings that can be used to narrow the differential diagnosis, including the criteria proposed by the International Autoimmune Hepatitis Group.

In patients with chronic liver disease, liver biopsies are taken to evaluate extent and progression of disease, which helps guide therapy. Here, we discuss the microscopic features of chronic hepatitis and the two most common histologic scoring systems used to evaluate liver biopsies with chronic hepatitis.

Steatohepatitis is a common finding on liver biopsies. The main differential diagnosis is non-alcoholic steatohepatitis (NASH) versus alcoholic steatohepatitis. When the histologic and clinical findings are most consistent with NASH, the liver biopsies are graded and staged based on one of the following scoring systems: the Brunt system, the NASH Clinical Research Network (NASH CRN) system, and the SAF scoring system. Here, we discuss the evaluation of liver biopsies with steatohepatitis.

When interpreting a liver biopsy, it is important to be familiar with the pathologist’s armamentarium of special stains. In this post, we review the most common histochemical stains used in liver pathology.

Why do patients get liver biopsies? The main goals of a liver biopsy are to (1) render a diagnosis in a patient with abnormal liver function tests (LFTs) or a liver lesion on imaging, (2) provide staging and grading in a patient with a history of chronic hepatitis, (3) assess the liver’s response to treatment, and (4) assess the function of a liver transplant.

The outer surface of the liver is composed of a fibrous / connective tissue capsule (Figure 1). The outermost surface is covered by a thin layer of mesothelial cells that arises from the peritoneum (Figure 2).