Several studies concerning isolated lactase deficiency have appeared recently.1-9 Agreement has not been reached, however, concerning the interpretation of human intestinal disaccharidase activity 10 and the lactose tolerance test.11,12 Previous studies from our laboratory reported early experience with oral tolerance tests using different amounts of lactose13 and described seven individuals with isolated lactase deficiency.14,15 Through a cooperative study involving three medical centers, we have now accumulated data on 47 individuals with this defect. The current report compares the findings in these persons with those in a group of subjects with normal lactase activity and presents our concept of the significance of an isolated lactase deficiency based on these results.
Material and Methods
The studies were done on 170 individuals. There were 109 males, 61 females, 145 whites, 22 Negroes, and three American Indians. The patients ranged in age from 3 to 80 years with only three
Welsh JD, Rohrer V, Knudsen KB, Paustian FF. Isolated Lactase DeficiencyCorrelation of Laboratory Studies and Clinical Data. Arch Intern Med. 1967;120(3):261–269. doi:10.1001/archinte.1967.00300030003003