Diarrhea is the second leading cause of death in children worldwide, and accurately assessing dehydration status remains a crucial step in preventing morbidity and mortality from this disease. While children with severe dehydration require immediate treatment with intravenous fluids, children with mild to moderate dehydration have a significant reduction in hospital length of stay and fewer adverse events when treated with relatively inexpensive oral rehydration solution (ORS). While several clinical scales have been developed for assessing dehydration in children, these scales have never been prospectively validated in a low-income country setting, where the vast majority of diarrhea morbidity and mortality occurs in children.

The investigators hypothesize that new clinical and ultrasound-based tools will improve the diagnosis of severe dehydration in children with diarrhea in low-income countries, reducing the morbidity and mortality that occurs as a result of under-diagnosis of severe dehydration as well as the adverse events and inappropriate utilization of scarce resources that occurs as a result of over-diagnosis of severe dehydration.

Background:

Children under five experience 1.7 billion episodes of diarrhea each year, resulting in 36 million cases of severe disease and 700,000 deaths, or 10% of all child deaths worldwide. As the severity of diarrheal disease can vary quite widely in children, accurately assessing dehydration status remains a crucial step in preventing morbidity and mortality. While children with severe dehydration require immediate treatment with intravenous fluids to prevent hemodynamic compromise, organ ischemia, and death, children with mild to moderate dehydration have a significant reduction in hospital length of stay and fewer adverse events when treated with relatively inexpensive oral rehydration solution (ORS). The World Health Organization (WHO), the US Centers for Disease Control and Prevention (CDC), and the European Society of Paediatric Gastroenterology, Hepatology and Nutrition (ESPGHAN) recommend separating children with acute diarrhea into three groups to determine management based on the presence or absence of various clinical signs: no dehydration (<3%), some dehydration (3-9%), and severe dehydration (>9%). These authorities recommend treating children with some dehydration with ORS and limiting IV hydration to children with severe dehydration, in order to prevent the inappropriate utilization of scarce hospital resources and the adverse events associated with a more liberal use of IV hydration in children. However, no clinical prediction model for severe dehydration has ever been empirically derived and validated in a developing world setting, where the vast majority of diarrheal deaths occur in children each year.

Study Objectives:

As part of this study, the investigators will derive a new clinical prediction rule for severe dehydration in children with diarrhea in the developing world. In addition, the investigators will validate and assess the reliability of ultrasound of the inferior vena cava (IVC) for predicting severe dehydration in children with diarrhea. Finally, the investigators will compare the accuracy of each of these new diagnostic tools to that of the WHO scale, the current standard for assessing dehydration in most low-income countries.

Study Design:

The investigators will enroll a prospective cohort of children under five admitted with diarrhea and dehydration to the Dhaka Hospital of the International Center for Diarrheal Disease Research, Bangladesh (ICDDR,B). Research staff will identify eligible children on arrival and obtain informed consent from their guardian. Children will be weighed on arrival and assessed clinically for the presence or absence of signs of dehydration. A brief ultrasound of the IVC will also be performed. Children will then be rehydrated according to standard hospital protocols, with their weight checked regularly until they achieve a stable, post-hydration weight. Greater than 9% difference between admission weight and stable weight (or post-illness weight) will be considered the gold standard for severe dehydration, against which the investigators will determine the accuracy of our new clinical and ultrasound-based assessment tools.

Ethical Protection of Human Subjects:

Children enrolled are very unlikely to be exposed to any additional risks or discomforts, either mental or physical, as a result of participating in this study. Study procedures will include physical exam and ultrasound, neither of which will expose children to increased harm, and study procedures will not delay any immediately necessary care, such as IV fluids. All data collected will be kept strictly confidential in a password-protected database. In addition to obtaining ethical approval from the Lifespan Institutional Review Board (IRB), the investigators have also already obtained approval from the ICDDR,B Ethical Review Committee.

Inclusion Criteria:

1. Age 5 years (60 months) or younger
2. History of diarrhoea (defined as 3 or more loose stools per day)
3. Children observed in the rehydration ward

Exclusion Criteria:

1. Chronic diarrhoea (greater than 2 week duration)
2. Clear alternative diagnosis to gastroenteritis on presentation
3. Previously enroled in this research study

Children under five with acute diarrhea observed in the rehydration ward of the Dhaka Hospital of ICDDR,B.