Role Of Zinc In Diarrhoea: Nestle

Speaker: Dr. Mohd. Rezaul Karim, M.D, Professor & Head of Department of Pediatrics Chittagong Medical College & Hospital. Chittagong, Bangladesh Presented at: Nestlé Nutrition Institute, Bangladesh

Summary

Arising from contaminated water and food resources, diarrhoea affects children below the age of 5years. Diarrhoea is fast becoming a leading cause of morbidity in children leading to the death of a million children every year. Caused by bacteria, virus and parasitic organisms, the majorly lasting impact ease is dehydration. Breast feeding, intake of Oral Rehydration Salts, and consumption of appropriate nutrient rich foods are some of the commonly undertaken sound measures to treat diarrhoea. Zinc supplements are beneficial in treating acute diarrhoea in children; it leads to increased levels of cellular immunity and antibodies. In stunted children, it enhances the rate of growth.

Diarrhoea is defined as the passage of 3 or more loose or liquid stools per day. It is the consistency of the stools rather than the number that is more important. Frequent passing of stool is not diarrhoea, nor is the passing of loose stools by breastfed babies. Diarrhoea mainly affects children under five years old. It is a leading cause of child morbidity and mortality in the world, and mostly results from contaminated food and water sources. Worldwide, around 1 billion people lacks access to safe water and 2.5 billion have no access to basic sanitation. There are four clinical types of diarrhoea, Acute watery diarrhoea which starts suddenly, most episodes recover or self-limiting within 3 -7 days, and may last up to 14 days. More than 75% of all episodes arc of acute watery diarrhoea. Acute bloody diarrhoea is one with visible blood in the faeces also called dysentery; and, abdominal cramps, fever, anorexia and rapid weight loss may present. Persistent diarrhoea starts acutely and lasts 14 days or longer. Five percent of acute diarrhoea may persist beyond 2 weeks. Chronic diarrhoea is one which lasts more than 4 weeks.

Diarrhoea is commonly associated with Zinc deficiency and it also leads to additional zinc losses. Zinc deficiency affects various mucosal functions: Disrupts intestinal mucosa, reduces brush border enzymes, increases mucosal permeability, and increases intestinal secretion. Zn helps to maintain the gut mucosal integrity to reduce or prevent fluid loss. Zn deficiency is biochemically defined as serum concentration less than 9 umoL/L. Low Zn greatly alters host defence systems, leading to opportunistic infections and mortality rates. On the other hand, short periods of Zn supplementation substantially improve immune defence in individuals with these diseases. It also leads to disturbances in the production and potency of several cytokines. Zinc supplements have been shown to have a beneficial effect on acute diarrhoea in children.

Zn supplementation is a new addition to the diarrhoea treatment strategy. Evidences have shown that Zn reduces overall diarrhoea prevalence by 25%, reduces hospitalization from diarrhoea by 30% and decreases its duration by 20%. It also reduces recurrences within ensuing 2-3 months by 35%. Zn is now being recommended for the standard case management of both dysenteric and non-dysenteric diarrhoea by WHO and UNICEF. A dose of 20 mg per day for 10-14 days for children and 10 mg per day for infants under 6 months has been recommended by WHO and UNICEF in acute diarrhoea.