alt55 generally refers to ALT 55U/L, which is slightly higher than normal. ALT is the acronym for alanine aminotransferase, with a normal reference range of 0 to 40 U/L (the reference range may be adjusted according to different measurement methods, depending on the local hospital.) ALT 55U/L, slightly higher than normal. ALT is mainly found in liver and myocardial tissue cells. When these tissues are diseased, it can cause a rise in serum levels of ALT, such as acute hepatitis, chronic active hepatitis, cirrhosis, fatty liver, hepatocellular carcinoma, and myocarditis, myocardial infarction, skeletal muscle disease and infectious mononucleosis. When there is an increase in alanine aminotransferase, it is recommended to consult a doctor in a timely manner to clarify the cause of the disease under the guidance of a professional physician, and to carry out targeted treatment.