Prevalence and outcome of hypernatremic dehydration among under-5 children with diarrhoea at the University Teaching Hospital,Lusaka,Zambia

Abstract

Introduction: Diarrhoea is the second commonest cause of under-five mortality globally (second to Pneumonia) and kills one (10 percent) out of every 10 children who die before their fifth birthday. In Zambia dehydration due to diarrhoea is a leading cause of morbidity and mortality among under-five children. Hypernatraemic dehydration is the most dangerous and fatal form of dehydration. Despite the availability of well known effective treatment modalities for dehydration in diarrhoea, mortality remains high in many developing countries. The situation is not any different in Zambia and at The University Teaching Hospital (UTH) Department of Paediatrics. In view of the high mortality of children due to diarrhoea, it is not known whether hypernatraemic dehydration could be a significant contributing factor. This study therefore sought to determine the prevalence and outcome of hypernatraemic dehydration as a possible contributing factor to the high mortality rate among children with diarrhoea. Objective To determine the prevalence and outcome of hypernatraemic dehydration among under-five children presenting with diarrhoea associated dehydration to UTH Department of Paediatrics. Method: The study was a prospective cohort study conducted at the UTH Department of Paediatrics. The study population was under-five children presenting with acute diarrhoea with dehydration. Independent variables were age, sex, feeding modality, prior ORS therapy, rotavirus vaccine status and serum sodium. The dependent or outcome variables were discharge/mortality and duration of hospital stay. Data analysis was done with the help of SPSS version 20. vi Results: There were a total of 148 participants with an almost 1:1 male/female ratio (73/75), mean age of 14.7 months ranging 1-60 months. The prevalence of hypernatraemic dehydration was approximately 19 percent (29/148) among children presenting with diarrhoea and dehydration. The prevalence is within the range of 10-20 percent cited in many previous studies, however relatively higher than most previous studies done in other countries. Hypernatraemia was associated with a high risk of mortality (7/29) with an OR 5.8 (adjusted OR 3.6, 95% CI 2.9- 8.0, p 0.002), compared to (7/74) OR 1.8 (adjusted OR 1.1, 95% CI 0.8-2.2, p 0.06), and (5/33) OR 3.1 (adjusted OR 2.3, 95% CI 1.7-4.4, p 0.03) for normal and low initial sodium level respectively. Hypernatraemia was also associated with longer hospital stay with a mean duration of 3.09 days (74.2hrs) compared to 2.01 days (48.2 hours) and 2.13 days (51.1 hours) for normal and low sodium respectively. Conclusion: Hypernatraemia is prevalent among under-five children presenting with diarrhoea at UTH department of peadiatrics and probably a major contributing factor to high diarrhoeal associated mortality. Recognition of its occurrence through diligent laboratory services is therefore critical for appropriate patient care. Key words: Under-five years, diarrhoea, dehydration, and hypernatraemia.