Criteria for Assessing Fat Absorption in Normal Subjects and Sprue Patients

Abstract

Summary 1. The literature dealing with absorption and excretion of fecal fat by normal subjects and sprue patients is reviewed. 2. In a series of 41 sprue patients and 19 normal subjects studied by us, in which the percentage of fat in dried feces was exclusively determined, only 29.2 per cent of the sprue and 5.3 per cent of the normals had more than 30 per cent fat in the dried feces. The limitations of this procedure for evaluating fat loss in normal subjects and sprue cases is discussed. 3. In another series, percentage fat in dried feces as well as percentage fat absorption, were determined in 7 normal and 7 sprue cases receiving similar care. The percentage of fat in dried feces indicated that 2 out of the 7 sprue cases suffered from abnormal fat absorption. On the other hand, the percentage fat absorption disclosed that 5 out of the 7 patients had definite signs of abnormal fat absorption. One of the 2 remaining sprue cases was a very early case. After repeated studies it always showed normal absorption. The other was a frank clinical case of sprue, which could not be properly evaluated because of low intake of fat. Daily fecal fat excretion of all the sprue cases averaged 12.5 gm., a value significantly higher than that obtained for the normals. None of the 7 normal subjects treated in a way similar to the sprue patients showed any signs of abnormal fat absorption either when the percentage of fat in dried feces or the percentage of fat absorption was used as an index to assess this condition. The daily fecal fat excretion of the normal group averaged 4 gm. 4. In both sprue and normal subjects the partition of the fecal fat was as follows: the split fat of the sprue group was slightly higher than the normals; the neutral fat was nearly the same as the normals, and the unsaponifiable matter was about half as large as the normals. The possible significance of these results is discussed.