What does stool osmotic gap mean?

Stool osmotic gap is a measurement of the difference in solute types between serum and feces, used to distinguish among different causes of diarrhea. Feces is normally in osmotic equilibrium with blood serum, which the human body maintains between 290–300 mOsm/kg.

What does stool osmolality mean?

What is this test? This test measures the concentration (osmolality) of certain particles in a sample of your watery stool. The amount of sodium, potassium, and other substances in your stool can affect its consistency. The test is used to find out why your stool isn’t solid.

What are stool electrolytes?

Sodium and potassium salts are the primary stool solutes. The sodium plus potassium concentration in stool usually ranges between 130 and 150 meq/L. Other cations, such as calcium and magnesium, are present at much lower concentrations.

What is a secretory diarrhea?

Diarrhea, defined as loose stools, occurs when the intestine does not complete absorption of electrolytes and water from luminal contents. This can happen when a nonabsorbable, osmotically active substance is ingested (“osmotic diarrhea”) or when electrolyte absorption is impaired (“secretory diarrhea”).

What is normal pH stool?

An acidic stool can indicate a digestive problem such as lactose intolerance, an infection such as E. coli or rotavirus, or overgrowth of acid-producing bacteria (such as lactic acid bacteria). The average pH for a healthy person has a reference range of 7.0 to 7.5.

Can a stool sample detect laxatives?

Thin layer chromatography (TLC) of urine or stool is the only commercially available test for these laxatives. Such testing is considered highly reliable, but its accuracy in clinical practice is unknown.

Are feces acidic?

The pH of human feces is variable but usually alkaline. An acidic stool can indicate a digestive problem such as lactose intolerance, an infection such as E. coli or rotavirus, or overgrowth of acid-producing bacteria (such as lactic acid bacteria).

How do you check pH of stool?

Test procedure At least half a milliliter of feces is collected, and a strip of nitrazine paper is dipped in the sample and compared against a color scale. A pH of less than 5.5 indicates an acidic sample.

What is the difference between a loose stool and diarrhea?

If you have diarrhea, you’ll also have loose or watery stools. However, if you have loose stools from time to time, it doesn’t mean you have diarrhea. In order for loose stools to be considered diarrhea, they have to occur repeatedly. If you have loose stools three or more times per day, then it’s diarrhea.

How do you lower stool pH?

Intake of oat bran (75−100 g/day over a 14-day period) has been shown capable of reducing fecal pH by 0.4 units. There is evidence, however, that high fecal pH may be secondarily rather than primarily related to cancer risk.

When to use stool osmolar / osmotic gap?

Stool Osmolar/Osmotic Gap. Determines if chronic diarrhea is osmotic or secretory in nature. Use with persistent (>4 weeks) watery diarrhea (>3 episodes/day) to guide diagnosis and treatment. Useful to determine whether chronic watery diarrhea is from osmotic or secretory causes.

What’s the difference between diarrhea and stool OSM?

The difference between the two types of diarrhea stands between the secreted sodium and potassium ions which make a big percentage of stool osm in secretory diarrhea while in the osmotic one they make up a small percentage of stool osm because of the other unabsorbed molecules being present,…

Why do I need an osmolality stool test?

This test also is used to find out whether your diarrhea is osmotic or secretory. Osmotic diarrhea results from something drawing water into your bowel. Secretory diarrhea happens when your body releases water into the bowel when it shouldn’t. Why do I need this test?