Pediatric Gastroenteritis in Emergency Medicine Workup

Updated: Apr 18, 2023
  • Author: Adam C Levine, MD, MPH; Chief Editor: Kirsten A Bechtel, MD  more...
  • Print

Approach Considerations

Workup of acute gastroenteritis should begin by using elements of the history and physical examination to determine the severity of dehydration, which in turn is used to guide overall management. Although the criterion standard for dehydration in children remains the percentage change between their pre-illness weight and admission weight, an accurate and recent pre-illness weight is rarely available in children presenting with acute gastroenteritis. [28]  Many clinical scales have been developed and recommended over the years for predicting dehydration severity in young children. [28, 29, 30, 31, 32, 33, 34, 35]  However, only the Dehydration: Assessing Kids Accurately (DHAKA) score and the Clinical Dehydration Scale (CDS) have been externally validated against a physiologic criterion standard (see Tables 1 and 2 below). Other clinical scales have shown mixed results in validation studies or have not been validated at all. [36, 37, 38, 39, 40, 41]

The CDS consists of four clinical characteristics: general appearance, eye level, mucous membranes, and presence of tears. [34, 38, 42, 43]  All clinical characteristics are measured on a 3-point ordinal scale, where the patient is given a value of 0, 1, or 2 for each assessment. The CDS is an 8-point rating scale with patients who score a 0 being categorized as having no dehydration, those with a score of 1-4 being categorized as having some dehydration, and those with a score of 5-8 having severe dehydration. [34, 38]  In its initial derivation study at a single hospital in Canada, the CDS had strong discriminatory power for detecting moderate-severe dehydration, with a Ferguson’s d of 0.83. [34]  A validation study conducted at three hospitals in Europe found a strong correlation between the CDS and the criterion standard of percent weight change with rehydration, as well as good reliability with a Kappa score of 0.65 (95% CI, 0.43-0.87). [37, 43]

The DHAKA Score comprises four clinical signs including general appearance, skin pinch, presence of tears, and respiration depth. It was derived in a prospective cohort study of patients under 5 years of age in Dhaka, Bangladesh, and later prospectively validated in both Bangladesh and Zambia. [33, 41, 42]  The DHAKA Score is a 12-point scale in which patients with a score of 0-1 are categorized as having no dehydration, 2-3 some dehydration, and 4-12 severe dehydration. [42]  Each 1-point increase in the DHAKA Score predicts an increase of 0.6% in the percentage dehydration of the child. [42]  Upon external validation in a new cohort of patients in Bangladesh, the DHAKA Score was found to be both accurate and reliable with an ordinal c-index of 0.82 and interclass correlation coefficient of 0.94. [40, 42]  More recently, the DHAKA Score was externally validated in Zambia where it had the highest accuracy for assessing dehydration among several different scores. [33, 43]

 Although concerns have been raised regarding the use of clinical signs for assessing dehydration in children with undernutrition (wasting), one study conducted in Bangladesh found that nutritional status did not impact the accuracy of the DHAKA Score or CDS. [44]

Table 1: Dehydration: Assessing Kids Accurately (DHAKA) Score (Open Table in a new window)

Clinical Sign Finding Points
General Appearance Normal 0
Restless/irritable 2
Lethargic/unconscious 4
Tears Normal 0
Decreased 1
Absent 2
Skin Pinch Normal 0
Slow 2
Very slow 4
Respirations Normal 0
Deep 2

Total: ≥4 severe dehydration, 2-3 some dehydration, 0-1 no dehydration.

Adapted from: External Validation of the DHAKA score and comparison to the current IMCI algorithm for the assessment of dehydration in children with diarrhoea. Lancet Global Health. 2016 Oct;4(10):e744-51.

Table 2: Clinical Dehydration Scale (Open Table in a new window)

General Appearance Normal Thirsty, restless, or irritable Lethargic or unconscious
Eyes Normal Slightly sunken Very sunken
Mucous Membranes Moist Dry Very dry
Tears Tears present Decreased tears Absent tears

Adapted from Parkin PC, Macarthur C, Khambalia A, Goldman RD, Friedman JN. Clinical and laboratory assessment of dehydration severity in children with acute gastroenteritis. Clin Pediatr (Phila). 2010 Mar;49(3):235–9.


Laboratory Studies

The vast majority of children who present with acute gastroenteritis do not require serum or urine tests, as they are unlikely to be helpful in determining dehydration severity. In a meta-analysis of 6 studies, among all laboratory tests only serum bicarbonate (< 17) had statistically significant positive and negative likelihood ratios for detecting moderate dehydration, and these were not better than current clinical prediction models. [45]

Clinically significant electrolyte abnormalities are rare in children with moderate dehydration. However, any child being treated with IVF for severe dehydration should have baseline electrolytes, bicarbonate, and urea/creatinine drawn. Laboratory tests may also be indicated in patients with diarrhea whose history and physical examination suggest etiologies other than infectious gastroenteritis.

Stool culture may be helpful in children presenting with bloody diarrhea or recent travel to a low-resource setting. Children older than 12 months of age with a recent history of antibiotic use should have stool tested for C difficile toxins. Those with a history of prolonged watery diarrhea (>14 days) or travel to an endemic area should have stool sent for ova and parasites or molecular testing for intestinal parasites.

Any child with evidence of systemic infection (ie, sepsis) should have a complete workup, including complete blood count (CBC), stool cultures, and blood cultures. If indicated, urine cultures, chest radiography, and/or lumbar puncture should be performed.


Imaging Studies

Abdominal films are not indicated in the management of acute gastroenteritis. If the clinician suspects a diagnosis other than acute gastroenteritis based on history and physical examination findings, appropriate imaging modalities should be pursued.

Several studies have evaluated the use of point of care ultrasound for assessing dehydration in children. Whereas ultrasound measurement of carotid flow time was found to be a poor predictor of severe dehydration in children with acute diarrhea, the inferior vena cava to aorta ratio has been shown to be statistically associated with dehydration severity. [46, 47, 48, 49]  However, more recent studies have not found ultrasound of the inferior vena cava to aorta ratio accurate enough to be used as an independent diagnostic tool for measuring dehydration severity in children with acute diarrhea, nor did it offer improvement over the accuracy of clinical examination alone. [50, 51]