What is steatorrhea? 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. Inflammation of the lining of the intestines, which may occur with conditions such as ulcerative colitis (inflammation of the colon and rectum), Crohn’s disease (inflammation of the bowels), and celiac disease (a severe sensitivity to gluten in the diet), can interfere with absorption of fats. Also, fat absorption may be affected by surgical removal of a portion of the intestines. Often, steatorrhea is a short-lived problem related to diet or infection; however, if it lasts for more than a couple of weeks, becomes more severe, or is accompanied by other symptoms, it may be due to a more serious condition. Seek immediate medical care (call 911) if you have bloody stool, black or tarry stool, stool with pus, severe abdominal pain or cramping, or high fever (higher than 101 degrees Fahrenheit). If your steatorrhea is persistent or causes you concern, seek prompt medical care.