[Acute diarrhea: stool water loss in hospitalized infants and its correlation with etiologic agents and lactose content in the diet].

Forty weaned male infants were studied during their first year of life, all hospitalized with acute diarrhea in the Gastroenterology and Metabolism Unit of the Hospital "Umberto I", São Paulo, SP, Brazil. We evaluated and quantified water fecal losses, employing the metabolic bed technique, relating the feeding formula employed with the different causal enteropathogenic agents. 67.5% of the studied infants were under six months and 40% under three months of age. Two groups were randomly assembled to receive, lactose or lactose free feeding formulae. Twenty one patients received a lactose-containing formula (Ninho 10%) and the other 19 children were fed caseine (Portagen) formulae. According to coproculture results and identification of enteropathogenic agents, we divided the studied infants relating feeding formula with the presence or absence of the enteropathogenic Escherichia coli (EPEC): I-13 with positive coproculture for EPEC and diets which included lactose--(L/EPEC+); II--eight with negative coproculture for EPEC and diets which included lactose--(L/EPEC-); III--seven with positive coproculture for EPEC and lactose free diets--(G/EPEC+); IV--12 with negative coproculture for EPEC and lactose free diets. (G/EPEC-). The most frequently isolated agent at coproculture was EPEC, in 20 of the cases (50%), followed by Campylobacter (7.5%). It was also possible to observe that the frequencies of EIEC, Salmonella and Rotavirus were all equal (2.5%). Mixed infections occurred only between EPEC and EIEC, registering a frequency of 5%. The EIEC samples, associated to EPEC 0111 were serotyped as 0 28 ac: H- and 0 152:H-. The use of metabolic bed made the evaluation of fecal volumes possible by a simple and quick technique, thus allowing a closer clinical monitoring, as well as a more reliable evaluation of the patients hospitalized with acute diarrhea. Average acceptance volumes of the formulae--either with or without lactose--were always below the amount recommended by FAO/WHO (100 kcal/day) which shows the impact of acute diarrhea on the decrease of food intake. The average volumes of watery fecal losses found among any of the studied subgroups may be considered quite relevant when compared to standard values. Especially within the L/EPEC+ group fecal losses, both on the first day (83.56 ml/kg/day) and, mainly, on the second (119.44 ml/kg/day) reached exceedingly high levels indicating a disastrous association between the presence of EPEC in the small intestine and lactose offer in the diet. Thus, the results show that there exists a positive and significant association between poor lactose absorption and the presence of EPEC in the feces. WHO's recommendation proposing the use of diluted cow milk, in universal and indiscriminate administration, in the two first days of the disease, may represent a risk factor, not only for malnutrition, but also for the survival rates of children with severe diarrhea, especially those under six months of age and hospitalized with EPEC enteroinfection.