SUMMARY 15N-yeast protein absorption, nitrogen and fat retention, stool reducing substances, and lactate concentrations were measured in 22 infants who had had severe diarrhoea for 7 days. Stool losses of nitrogen and fat were large. and an appreciable proportion appeared to be endogenous. The supply of nitrogen and energy might have been a limiting factor in tissue repair if stool weight exceeded 30 g/kg body weight a day. These results differ from those in older children with kwashiorkor complicated by diarrhoea of similar severity. There are also differences in cellular immunity3 and gut morphology.4This paper reports the results of a study on protein absorption and nitrogen and fat balance in infants with prolonged diarrhoea.
Patients and methodsThe infants aged between 3 weeks and 1 year had a history of diarrhoea for less than 72 hours when they were admitted to hospital for intravenous rehydration. Diarrhoea persisted and 6 days after admission they still required intravenous fluids to maintain hydration. No antibiotics or chemotherapeutic agents other than penicillin had been given and most infants had been fed on full-cream or modified cows' milk formula followed by a soybased formula. There was no oedema, and none of the skin lesions associated with nutritional diseases.On day 7, 35 boys were taken into the study and nursed on metabolic beds for 5 days. Routine investigations included urine and stool specimens examined microscopically and cultured. Blood culture, haemoglobin, total serum protein, serum protein electrophoresis, serum electrolytes, pH, Pco2, and standard bicarbonate estimations were also done. If clinically indicated the investigations were repeated. All the infants were given parenteral penicillin and gentamicin in case of undetected infection.During the first 24 hours all the infants received 120 ml of full-cream cows' milk formula per kg body weight. Infants were then allocated randomly to one of 3 commercial feeds; a full-cream cows' milk formula (Nespray), a soy-based formula with the carbohydrate as sucrose (Sobee), or a casein-based, low-lactose formula with glucose as the principal carbohydrate (AL 110). If the bacteriological screening tests showed that an infant had a urinary tract infection, a known pathogen in the stool, or a bacteraemia, he was excluded from the study. Three infants who were subsequently found to have monosaccharide intolerance were also excluded. The