Clinical Chemistry, Vol 29, 545-548, Copyright © 1983 by American Association for Clinical Chemistry

Sensitivity and specificity of the hydrogen breath-analysis test for detecting malabsorption of physiological doses of lactose

JL Rosado and NW Solomons

We examined the changes in sensitivity and specificity that would occur with alterations in the sample-collection schedule and (or) cutoff criterion for the increase in hydrogen concentration in breath after administration of doses of lactose in the dietary range. In a breath- analysis test to classify individuals as lactose-absorbers or lactose- malabsorbers, 41 subjects drank 360 mL of intact cow's milk, containing 18 g of lactose, and breath samples were collected and analyzed at 30- min intervals for 5 h. An increase in H2 concentration of greater than or equal to 20 microL/L above basal values at any of the 10 intervals was diagnostic of malabsorption. Increases of greater than or equal to 18 or greater than or equal to 15 microL/L were only 85% as specific in classifying the same individuals. Reduction in the number of samples tested per subject uniformly reduced the sensitivity. However, a simplified procedure suitable for field studies (in which four samples-- at 0, 2, 3, and 4 h--are collected and analyzed with greater than or equal to 20 microL/L as the cutoff value) gives 80% sensitivity and 100% specificity, as compared with the 11-sample procedure.

The following articles in journals at HighWire Press have cited this article:

				E. Renner Dietary approaches to alleviation of lactose maldigestion / Efectos de la dieta sobre la digestion de la lactosa Food Science and Technology International, January 1, 1997; 3(2): 71 - 79. [Abstract] [PDF]