The role of Ascaris lumbricoides in the nutrition of the host effect of ascariasis on digestion of protein

Abstract
1. (1) An investigation was undertaken to determine the effect of moderately heavy or heavy infestation with Ascaris lumbricoides on the digestion and absorption of protein in poorly nourished children. Nine children harbouring roundworms were maintained in hospital for 18 to 19 days on a diet permitting a constant nitrogen intake throughout the experimental period. Faecal nitrogen in 24-hour collections of faeces before and after worming was estimated. 2. (2) In every one of the subjects investigated, the faecal nitrogen per 24 hours was lower after disinfestation than that excreted prior to worming. The average values for faecal N were 1.315 g. and 0.755 g. per 24 hours respectively. The difference was statistically highly significant. 3. (3) A method has been described for the determination of the N content of ascaris eggs. In four children, the egg N component varied from 19.2 to 26.1 mg. per 24 hours in a total faecal N range of 0. 875 g. to 2.470 g. 4. (4) In two worm-free subjects it was demonstrated that the administration of anthelmentic and cathartic did not cause a fall in faecal N as was observed after worming in nine worm-carrying children. 5. (5) In view of the above, it is suggested that in nine children investigated above, the presence of Ascaris lumbricoides in the small intestine interfered with the digestion and absorption of dietary protein. The probable ways in which this interference is caused have been discussed. 6. (6) It is further suggested that when the protein in the diet is inadequate, incomplete digestion resulting in deficient absorption of protein may be of great significance as one of the aetiological factors in the causation of nutritional oedema syndrome (kwashiorkor) which, in young children, is the result, primarily of subacute protein deficiency.