Fatty or Thick Stool
Buttock Rectum | Gastroenterology | Fatty or Thick Stool (Symptom)
Steatorrhea is the medical term for fat in stool. Fat in the stool can cause bulky stool that floats, has an oily or greasy appearance, and smells foul. Fat in the stool is fat that the digestive tract was unable to absorb. Temporary steatorrhea may result from dietary changes or intestinal infections. Steatorrhea that is persistent may result from diseases of the biliary tract, pancreas, or intestines.
Fat absorption is dependent upon bile (which is produced in the liver and stored in the gallbladder), pancreatic lipases (enzymes that break down fat), and normal intestine function. Absence of bile is often due to blockage of the biliary tract and can result in pale colored fatty stool and jaundice. Absence of pancreatic lipases is uncommon, but can occur as a result of a diseased pancreas, cystic fibrosis, or an abnormality that is present at birth.
Possible biological causes can be lack of bile acids (due to liver damage, hypolipidemic drugs, or having had the gallbladder removed in a cholecystectomy), defects in pancreatic enzymes, and defective mucosal cells. The absence of bile acids will cause the feces to turn gray or pale. Another cause of steatorrhea is due to the adverse effect of octreotide or lanreotide, which are analogs of somatostatin, used clinically to treat acromegaly. Steatorrhea can also be due to eating indigestible oils or fats, such as Olestra, or as a side effect of medicines that prevent the absorption of dietary fats, such as Orlistat.