Nutritional effects and management of diarrhoea in infancy.

The interactions between diarrhoeal disease and nutritional status are complex and synergistic. These are serious issues globally because they affect hundreds of millions of young children and annually cause > 3 million deaths in children aged under 5 y. Despite intensive field-based and laboratory studies over three decades, many questions remain unanswered about the causes, pathophysiology and best approaches to management and prevention of this "diarrhoea-malnutrition" syndrome. Oral rehydration therapy (ORT) has been a major advance and has saved many lives from acute diarrhoea. However, persistent diarrhoea is now a major problem and is very significant because of its strong negative impacts on nutritional status and because persistent diarrhoea and dysentery are now major causes of infant and young child deaths. ORT provides clear and practical methods for replacement of fluid and electrolyte losses during diarrhoea. Rehydration salts can be made available as (i) a simple, easy-to-use package, complete with user instructions; (ii) cereal-based formulae based on widely available ingredients that can be prepared domestically or commercially; and (iii) home-made mixtures of sugar and salt which should be simple to prepare but are risky because of inadequate understanding about their preparation at home and the chance of mixing the ingredients inaccurately and giving them wrongly. Continuation and encouragement of breastfeeding is an important strategy to prevent and control diarrhoea and as part of its management. Early refeeding during diarrhoea is another important principle to help to reduce its duration, severity and its nutritional impacts. Supplementation with specific dietary ingredients, such as vitamin A, zinc and folate, is rather contentious and drug therapy is of little value unless specifically indicated. Some patients may require enteral nutrition or parenteral nutrition but these require specialized equipment and skills that are usually beyond the reach of developing countries and infants and children who live in remote areas.