THE lactose intolerance is diagnosed from the correlation of symptoms and clinical aspects of the patient with some tests available.
O lactose intolerance test assesses the absorption capacity of lactose by the intestine. The patient ingested, in a fast, a liquid that contains lactose. The blood glucose level is evaluated before and after the ingestion of the liquid to compare. If there is no increase in blood glucose, the test is considered positive and intolerance can be proven to depend on the correlation of clinical symptoms.
Another test that can be done is expired hydrogen test. In this test, the patient also fasted the lactose-containing substance and, after a few hours, the rate of hydrogen at the expiration is evaluated. When it is high, it indicates that lactose is not being adequately absorbed by the body and therefore the possibility of lactose intolerance is high.
Another less commonly used test is the measurement of fecal acidity. This test is performed from the stool just eliminated by the person. When acidity is high there is a high chance of being due to lactose intolerance.
These examinations may be requested after the clinical evaluation of the gastroenterologist, general practitioner or family doctor.
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