PT Test

Prothrombin Time (PT):

Another measure of hepatic synthetic function is the prothrombin time. Prothrombin time is affected by proteins synthesized by the liver. Particularly, these proteins are associated with the incorporation of vitamin K metabolites into a protein. This allows normal coagulation (clotting of blood). Thus, in patients who have prolonged prothrombin times, liver disease may be present. Since a prolonged PT is not a specific test for liver disease, confirmation of other abnormal liver tests is essential. This may include reviewing other liver function tests or radiology studies of the liver. Diseases such as malnutrition, in which decreased vitamin K ingestion is present, may result in a prolonged PT time. An indirect test of hepatic synthetic function includes administration of vitamin K (10mg) subcutaneously over three days. Several days later, the prothrombin time may be measured. If the prothrombin time becomes normal, then hepatic synthetic function is intact. This test does not indicate that there is no liver disease, but is suggestive that malnutrition may coexist with (or without) liver disease.

Use the table below for reference