Stool_Osmotic_Gap v.1
Stool osmotic gap determines if chronic diarrhea is osmotic or secretory in nature.
To calculate the stool osmotic gap.
Use with persistent (>4 weeks) watery diarrhea (>3 episodes/day) to guide diagnosis and treatment. The calculation relies on the assumption that stool osmolarity is fairly constant and similar to serum osmolarity (290-300 mmol/L). Formula: Stool Osmolal Gap = Stool Osm - (2 * (Na + K))
Not to be used in the evaluation of acute diarrhea.
1. Eherer AJ, Fordtran JS. Fecal osmotic gap and pH in experimental diarrhea of various causes. Gastroenterology. 1992 Aug;103(2):545-51. doi: 10.1016/0016-5085(92)90845-p. PMID: 1634072.
OBSERVATION.stool_osmotic_gap.v0, OBSERVATION.lab_test_stool.v0
