Steatorrhea

Definition: What is Steatorrhea?

Steatorrhea (pronunciation: stē′ətərē′ə) came from the Greek words “stear” meaning “ fat,” and “rhoia” meaning “flow” [1].


Steatorrhea refers to elimination of fat in the stool basically because the intestines cannot absorb it well. It is further described as foul-smelling, pale, pasty, spongy, and bulky. This is the third most common cause of chronic diarrhea [2, 3, 4].

Pictures: What does Steatorrhea Look Like?

Image Source: steatorrhea.org

Steatorrhea caused by Orlistat (drug for weight loss)
Image Source: steatorrhea.org

Causes of Steatorrhea

Liver Diseases

Hepatitis, Primary Biliary Cirrhosis, Extrahepatic Biliary Obstruction

Conjugated bile salts are needed for digestion of fat. Conjugation happens in the liver. If there is disease of the liver such as those mentioned above, there will be deficient bile salts and fat malabsorption. Eventually, cirrhosis (chronic liver inflammation, cell degeneration, tissue thickening) develops, causing steatorrhea.

Short Bowel Syndrome

Short bowel syndrome is mostly associated with surgical removal of the ileum (the third part of small intestine). This also occurs in diseases wherein a large portion of the intestine does not serve its purpose, e.g. Crohn’s disease, radiation enteritis, chemotherapy. Bile acid salts should be reabsorbed in the small intestines but this becomes impaired in short bowel syndrome. This further results to malabsorption of fat [2].

Zollinger-Ellison Syndrome

Zollinger-Ellison Syndrome (ZES) is caused by gastrinoma, a tumor in the stomach. In ZES, there is an excess production of acid in the stomach. When pancreatic enzymes are exposed to this, they become inactivated. Lipase is a pancreatic enzyme that digests lipids or fats. If they become inactivated, there will be less absorption of fat, hence the steatorrhea [2, 5].

Intestinal Stasis

Stasis or dysmotility of the intestine can be caused by scleroderma or diabetes. If intestinal contents are not properly moved by peristalsis, bacterial overgrowth may develop. Normally, metabolism and deconjugation of bile acids happens in the large intestine but in this case, the bacteria metabolizes the bile acids early in the small intestine [2].

Parasitic Infections: Giardiasis, Isosporiasis, Strongyloidiasis

Giardiasis is caused by the parasite Giardia lamblia. The exact pathophysiology on how it induces steatorrhea is unknown but it most probably destroys the intestinal mucosa or deconjugates the bile salts. In every case of unexplained steatorrhea, giardiasis must be considered [5].Isosporiasis, caused by Isospora belli, is usually seen among immunocompromised patients [6].

Half of patients with strongyloidiasis, most commonly caused by Strongyloides stercoralis, show no signs and symptoms. Acute infections involve the gastrointestinal and pulmonary systems while chronic infections involve integumentary and nervous systems [7].

These parasites damage the brush border of the intestines, inhibiting the absorption of fat and nutrients [8].

Foods and Drugs

  • The following are the foods and drugs known to cause steatorrhea:
  • Peanuts
  • Laxatives
  • Bile acid sequestering resins: Cholestyramine and Colestipol
  • Olestra
  • Liquid paraffin
  • Colchicine
  • Para-aminosalicylic acid
  • Antibiotics: Tetracycline and Neomycin [2]

Diagnosis of Steatorrhea

The patient comes into the clinic with a history of oily or greasy stools that are malodorous. It often leaves a stain in the toilet bowl. Associated manifestations include weight loss, bloating, and flatulence [2, 3].

Steatorrhea is quantitatively diagnosed by 72-hour collection of fat in the stool. This is the gold standard in identifying steatorrhea. The patient takes in 100 grams of fat per day and stool is collected every 24 hours for three days. Excretion of less than 7 grams per day is considered normal. 7-14 grams per day most likely suggests malabsorption syndrome although it is not definitive because mild to moderate diarrhea and ingestion of mineral oil or castor oil can also produce steatorrhea.

If fecal fat is more than 14 grams per day, there may be maldigestive or malabsorptive disease. Highest yield of steatorrhea is caused by severe pancreatic diseases like chronic pancreatitis or carcinoma of the pancreas. The levels may reach fecal fat of more than 35 g/day.

Qualitatively, steatorrhea can be diagnosed with the use of Sudan black stains. More than 80% of patients with true steatorrhea test positive for this. This is used as a screening test or if 72-hour fecal fat collection cannot be performed. It has the ability to differentiate malabsorption of triglycerides versus free fatty acids.

However, it can only be useful if the patient has moderate to severe steatorrhea because it only correlates well with the 72-hour fecal fat collection if the value is more than 15 g/day [3, 5, 9].

Treatment of Steatorrhea

Restriction of Dietary Fat

In steatorrhea, there is excess fat in the stool, therefore the primary treatment is to lessen what is in excess. But restriction does not mean total cessation of fat intake because our body needs fat in order to function. In patients with pancreatic exocrine insufficiency, limitation to 20g of dietary fat is acceptable.

Supplemental Pancreatic Enzymes

If restriction of dietary fat is not possible or not effective, supplemental pancreatic enzymes (SPE) are necessary. To have a well-absorbed fatty meal, pancreatic lipase of 30,000 IU is generally required. The amount may be decreased for snacks. It is important to note that SPE should be taken during meals, not before or after, for maximal absorption.

When eating, secretion of gastric acid is stimulated. SPE is inactivated by gastric acid. Medications that control gastric pH is necessary to ensure effectiveness.

Supplementation of Fat-Soluble Vitamins

Fat-soluble vitamins (vitamins A, D, E, and K) are supplemented to all patients with chronic pancreatitis where steatorrhea or maldigestion is noted.

Medium-Chain Triglycerides

There are rare cases wherein SPE renders ineffectiveness. If this, plus weight loss and persistent steatorrhea occurs, medium chain triglycerides are given as supplements because they do not need lipase in order to be absorbed in the intestines, thus providing the patient fat-derived calories needed by the body [10].

Antibiotics

Antibiotics are given to patients whose steatorrhea is caused by bacterial overgrowth.

Bile Acid Sequesters

Cholestyramine is a bile acid sequester given to patients with steatorrhea if the cause is bile acid malabsorption [3].

References

  1. Mosby’s Medical Dictionary, 8th edition, 2009. Retrieved from http://medical-dictionary.thefreedictionary.com/steatorrhea
  2. Paulman PM, Paulman AA, Harrison JD. Taylor’s 10-Minute Diagnosis Manual: Symptoms and Signs in the Time-Limited Encounter, Lippincott Williams & Wilkins, 2006
  3. Cheifetz AS, et al. Oxford American Handbook of Gastroenterology and Hepatology, Oxford University Press, USA, 2011
  4. Brunzel NA, Fundamentals of Urine and Body Fluid Analysis, Elsevier Health Sciences, 2013
  5. DiMarino AJ & Benjamin SB, Gastrointestinal Disease: An Endoscopic Approach, 2nd edition, SLACK Incorporated, 2002
  6. http://emedicine.medscape.com/article/219776-clinical
  7. http://emedicine.medscape.com/article/229312-clinical
  8. Rose S, Gastrointestinal and Hepatobiliary Pathophysiology, Hayes Barton Press, 2004
  9. Humes HD, Kelley’s Essentials of Internal Medicine, Lippincott Williams & Wilkins, 2001
  10. Wilson T, Nutrition Guide for Physicians, Springer Science & Business Media, 2009

Published on by under Diseases and Conditions.
Article was last reviewed on September 11th, 2016.



Leave a Reply

Back to Top