ED Management of Pediatric Gastroenteritis

          Gastroenteritis is an extremely common presentation in the pediatric ED, accounting for nearly 1.5 million annual visits in the US. Of these visits, approximately 200,000 children are hospitalized with nearly 300 resulting in death. Abroad in developing countries, the numbers are starker with nearly 2 million annual deaths from gastroenteritis – this comprises one third of all-cause mortality for children under the age of 5 (1).

Approximately 80% of gastroenteritis cases are caused by viruses with rotavirus, adenovirus, and Norwalk virus comprising the predominant species. Bacterial infections are less common in developed countries, and symptoms are usually attributed to E. coli, Campylobacter, Salmonella species, and Shigella species (1).

Gastroenteritis occurs when there is inflammation of the lining of the stomach and intestines, which leads to the typical symptoms of nausea, vomiting, diarrhea, and abdominal discomfort. Regardless of the source of infection, gastroenteritis is concerning in the pediatric population due to the associated fluid shifts, which can lead to dehydration, shock, and death. Dysentery is present when a bacterial infection leads to blood, mucus, or pus in the stool.

Gastroenteritis is a clinical diagnosis which does not require routine lab testing or imaging.(2) Testing is typically performed only when alternative diagnoses may need to be ruled out (i.e. appendicitis) or if red flags on presentation make you concerned about the severity of the gastroenteritis. Important screening factors to consider during a gastroenteritis workup include the following:

• History
  • Age < 6 mos
  • Bloody or mucous stools
  • Immunocompromised state
  • Travel history
  • Extended length of symptoms
  • Persistent fevers
  • Bloody or bilious emesis
  • Severe abdominal pain
  • Decreased wet diapers
  • Recurrence of symptoms
  • Recent antibiotic use

• Exam
  • Evidence of severe dehydration
  • Abdominal tenderness
  • Peritoneal signs
  • Altered mental status
  • Petechiae, purpura
  • Multiple organ involvement

          The morbidity and mortality associated with gastroenteritis typically arises from dehydration. Fluid shifts lead to poor fluid absorption and increased fluid loss. The associated anorexia and refusal to eat can exacerbate the condition. Assessing the level of dehydration will help better understand the severity of the illness, and help guide management and disposition.

The gold standard for calculating degree of dehydration is by dividing the weight lost during the illness by the total weight of the individual. This calculation, however, requires the pre-illness weight which is not always readily available:

Dehydration = (Pre-illness weight) – (Current weight) / (Pre-illness weight)

For example, if a 20 kg child comes in weighing 18 kg, they are (20-18)/20 = 10% dehydrated. This means that the child is 20 kg x 10% = 2 kg dehydrated. This implies the child has lost 2 L of fluid during his/her illness.

To address this problem, the WHO created a clinical tool aimed to help clinicians estimate dehydration level based upon the physical exam:

Table 1: Clinical Criteria Tool Used for Classifying Dehydration Severity
From: Hostetler, 2004 (1)

• Hydration
  • Oral rehydration (i.e. with oral rehydration solution or equivalent) is preferred in mild-moderate cases of dehydration
  • IV hydration is recommended in children who are not tolerating oral rehydration or are severely dehydrated
• Medications
  • Antiemetics, such as ondansetron, are safe adjuncts to oral rehydration
  • Bismuth salts (i.e. peptobismol) is a safe adjunct to oral rehydration
  • Antidiarrheals are not recommended
  • In the presence of hypoglycemia, D10 is recommended in infants and D25 in toddlers or adolescents
• Antibiotics
  • Empiric antibiotics are not recommended due to most cases being viral in origin
  • Even if a bacterial cause is suspected, antibiotics should not be employed unless a specific etiologic agent is identified or strongly suspected
• Lab work
  • Routine blood work is not recommended unless there is a concern for significant dehydration, which may predispose to electrolyte abnormalities (i.e. hypernatremia, hypokalemia), or an alternative diagnosis is being entertained
  • Additional tests to consider in the appropriate clinical setting include blood cultures, stool culture, stool ova and parasites, and stool leukocytes

Several groups of children may benefit from admission to the hospital

•       Severely dehydrated children
•       Mild-moderately dehydrated children who are unable to tolerate PO
•       Patients with risk factors or comorbidities (age < 6 mos, immunocompromised)
•       Patients with high probability of outpatient failure (i.e. social factors, complications from their        presentation, failure of outpatient therapy, etc…)