Conventional malabsorption tests: do they detect the adult patient with villous atrophy?

A total number of 134 patients with subtotal or partial villous atrophy, of whom 49 had dermatitis herpetiformis, were investigated with blood folate assay and xylose and lactose absorption tests. Faecal fat excretion was determined in 71 patients without dermatitis herpetiformis (coeliac group). A comparison was made between three patient groups, the patients with dermatitis herpetiformis and the coeliac patients studied in 1970-74 and 1975-79, respectively. From clinical and biochemical analyses of these patients we conclude that although a combination of the four malabsorption tests used here still detect a majority of coeliac patients, small intestinal biopsy may reveal villous atrophy also in patients without any laboratory evidence for malabsorption by these commonly used tests. In dermatitis herpetiformis, however, the sensitivity of the tests used was low; these malabsorption tests therefore have little diagnostic value in this category of patients.