Lesser quantities are found in the kidneys, heart, and skeletal muscle. Injury or disease affecting the liver parenchyma win cause a release of this hepatocellular enzyme into the bloodstream, thus elevating serum ALT levels. Generally, most ALT elevations are caused by liver dysfunction. Therefore this enzyme is not only sensitive, but also quite specific in indicating hepatocellular disease. Useful for hepatic cirrhosis, and other liver disease.
Diagnostic codes are to be used at their highest level of specificity.
Fourth and fifth digits should be utilized when they are available. EMC and hard copy claims will be monitored for appropriateness and frequency. Medicare does not provide coverage for tests obtained for screening purposes or for tests obtained for medically unnecessary indications. Follow-up testing performed at a frequency greater than is necessary for the reasonable medical management of the patient's condition is not covered. Ravel, R., Clinical Laboratory Medicine, 5th Edition, pg.