Fecal Fat

From Health Facts
Jump to: navigation, search
Latest Edit: Hector 2014-03-24 (EDT)

See Also Lab Tests

The Fecal Fat test is conducted to confirm the diagnosis of steatorrhea. Steatorrhea may be suspected when a patient has large, greasy, and foul-smelling stools. An abnormal high fecal fat content can confirm this diagnosis.[1]


  • This test measures the fat content in stool.
  • The most reliable measurement can be obtained from a total output of fecal fat per 24 hours in a 3-day stool collection.
  • Any condition that may cause malabsorption or maldigestion is associated with fecal fat.

Patient Preparation

  • Patient may be given instructions on an appropriate diet.
  • Factors which can cause increased levels
  • Drugs: enemas and laxatives, especially mineral oil
  • Factors which can cause decreased levels
  • Drugs: Metamucil and barium

Clinical Implications

High levels indicate:

  • Cystic fibrosis
  • Malabsorption secondary to sprue, celiac disease, Whipple disease, Crohn disease (regional enteritis), or radiation enteritis
  • Maldigestion secondary to obstruction of the pancreatobiliary tree (e.g., cancer, stricture, gallstones)
  • Short-gut syndrome secondary to surgical resection, surgical bypass, or congenital anomaly

Low levels indicate:

  • None noted

Associated Tests

  • D-Xylose absorption


  1. Pagana Kathleen D, Pagana Timothy J (2006) Mosby's Manual of Diagnostic and Laboratory Tests, Mosby.