Macro-Aspartate Aminotransferase and Monoclonal Gammopathy: A Review of Two Cases

Excerpt

Aspartate aminotransferase (AST), also known as glutamic-oxaloacetic transaminase, is one of several enzymes that exist in macromolecular form as a result of their association with other molecules, generally immunoglobulins [2]. In clinical practice, elevation of AST is generally associated with hepatic pathology. Hepatologists are commonly called to make associations between elevated transaminases and any of a number of potential causes of liver disease. Macro-AST has been detected in diseases such as acute and chronic hepatitis, other autoimmune diseases, and malignancies of the stomach, breast, and prostate [3]. Herein we present two patients who presented for medical care in the setting of hematological abnormalities in whom evaluation of hepatic function was requested due to elevated AST levels; these cases illustrate the possibility of macro-AST in patients with elevated enzyme immunoglobulin G (IgG) [1]. …