JACHO Notice

Stool Acidity Test

This procedure is used to diagnose lactose intolerance in infants and children.  In adults, lactose intolerance is diagnosed using the lactose tolerance test or hydrogen breath test.  Lactose is the predominant sugar found in milk.  This procedure is preferred for young children and infants because of the large doses of lactose required for other types of diagnostic testing, which could lead to diarrhea and, ultimately, dehydration in young people.

In addition to producing hydrogen and other gases in the colon, certain bacteria also produce lactic and other acids which are excreted in the stool.  In this procedure, the patient is given a small sample of lactose to ingest.  If the lactose is not digested properly, the bacteria in the colon will produce acid and the acidity level of the stool will rise.  This rise in acid level can then be measured and a lactose intolerance diagnosis can be made.