differential diagnosis of prolonged PT and PTT

Last reviewed 01/2018

Diseases which may increase both PT and PTT include:

• liver disease
• vitamin K deficiency
• disseminated intravascular coagulation
• heparin
• warfarin
• isolated factor deficiencies - II, V, X - all rare

Note:

• vitamin K deficiency is distinguished from liver disease by its response to vitamin K therapy
• platelet count and fibrinogen levels are usually decreased in DIC but normal in vitamin K deficiency and liver disease