Gastroenteritis

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Objectives

Upon finishing this module, the student will be able to:

Identify the causative organisms of pediatric gastroenteritis.
Investigate the presenting features of pediatric gastroenteritis.
Describe levels of severity of dehydration and appropriate treatment.

Contributors

Update and Original Author: James Waymack, MD.

Update Editor: Jessica Pelletier, DO, MHPE.

Last Updated: November 2024

Introduction

Pediatric gastroenteritis is a common illness that accounts for many visits to the emergency department (ED). Gastroenteritis refers to a condition of inflammation of the stomach or intestines that is manifested as nausea, vomiting, or diarrhea, and is considered acute when present for less than two weeks. By definition, the diagnosis of gastroenteritis should be supported by historical components of both vomiting and diarrhea. While often a benign and self-limited illness, there can be severe morbidity and mortality associated with gastroenteritis.

Gastroenteritis can be due to viral, bacterial, or parasitic pathogens, most often transmitted via the fecal-oral route or via contaminated food or water. The most prevalent viral cause of gastroenteritis in children worldwide is rotavirus. Rotavirus has been on the decline due to increasing vaccination rates, and the most common viral etiology for gastroenteritis in the United States is now norovirus. Enteric adenoviruses are also quite common.

The most common bacterial pathogen in developed countries is Campylobacter jejuni and other common pathogens (in order of prevalence) include Staphylococcus (S.) aureus, Salmonella, Clostridium (C.) perfringens, Shiga toxin producing E. coli (STEC), Shigella, Yersinia enterocolitica, non-cholera Vibrio species, and enterotoxigenic Escherichia coli. C. perfringens, Bacillus cereus, and S. aureus all cause illness via preformed toxins and are thus responsible for a more rapid onset of symptoms. Preformed toxins typically cause self-limited illness that lasts 24-48 hours. While C. difficile is considered the most common cause of antibiotic-induced diarrhea in adults it has historically been less common in pediatric patients. Of note, community-associated C. difficile infections have been on the rise in pediatric patients and should be considered in some cases.

Parasitic causes of acute gastroenteritis may be due to Cryptosporidium parvum, Entamoeba histolytica and Giardia lamblia. Specific risk factors for parasitic gastroenteritis include travel to endemic areas, ingestion of unfiltered water, or immunocompromised status. Fungal gastronteritis is incredibly uncommon except in cases of immunocompromise.

One must also consider other disease processes in the child who presents with abdominal pain, vomiting, or diarrhea. If any of these symptoms appears as an isolated chief complaint or the history is not consistent with sick exposures or ingestion of contaminated food products, the differential diagnosis should be expanded to include other congenital or anatomical causes of the symptoms. Though not an exhaustive list, other differential diagnoses that should be considered for pediatric patients with isolated vomiting should include inborn errors of metabolism, diabetic ketoacidosis, intussusception, pyloric stenosis, malrotation with volvulus, other bowel obstruction, migraine (including abdominal migraine), cyclic vomiting syndrome, cannabinoid hyperemesis syndrome, and increased intracranial pressure. Prematurely or incorrectly diagnosing a child with gastroenteritis could lead to misdiagnosis and further morbidity or mortality.

Common Causes of Pediatric Gastroenteritis

Bacteria

Bacteria	Incubation	Signs and Symptoms	Duration	Associated Foods	Testing	Treatment
Campylobacter jejuni	1-5 days	Diarrhea (may be bloody), cramps, fever, vomiting	5-7 days (sometimes 10+ days), usually self-limiting	Poultry, unpasteurized milk, contaminated water	Routine stool culture. Requires special culture media to grow at 42 C Antigen PCR.	Supportive care. First-line treatment is azithromycin. Quinolones may be used as alternatives, though resistance rates for azithromycin and quinolones are both rising. Amoxicillin clavulanate may be another alternative in susceptible cases. Bacteremia and extra-intestinal manifestations may occur. Guillain-Barre syndrome and reactive arthritis can be sequelae.

Bacteria	Incubation	Signs and Symptoms	Duration	Associated Foods	Testing	Treatment
Staphylococcus aureus (preformed toxin)	1-6 hours	Sudden onset of severe nausea and vomiting, abdominal cramps. Diarrhea and fever may be present.	1-3 days	Unrefrigerated or improperly refrigerated meats, potato and egg salads.	Clinical diagnosis. Routine stool culture can identify organism.	Supportive care.

Bacteria	Incubation	Signs and Symptoms	Duration	Associated Foods	Testing	Treatment
Salmonella	1-5 days	Diarrhea (possibly bloody), fever, vomiting, abdominal cramps.	5-7 days	Contaminated eggs or poultry, reptiles/amphibians and birds, raw fruits and vegetables, oral-fecal route.	Routine stool cultures or PCR.	Supportive care. Antibiotics not indicated unless S. typhi or S. paratyphi with extra-intestinal spread. Consider amoxicillin, ceftriaxone, ciprofloxacin, or ampicillin, gentamicin, TMP-SMX or quinolones for non-typhoidal S. enterica. For S. enterica typhi or paratyphi, ceftriaxone or ciprofloxacin are first-line; ampicillin, azithromycin, and TMP-SMX are alternatives. Reactive arthritis and erythema nodosum can be sequelae

Bacteria	Incubation	Signs and Symptoms	Duration	Associated Foods	Testing	Treatment
C. perfringens	8-14 hours	Abdominal cramping, watery diarrhea, vomiting, fever.	12-24 hours	Contaminated food ingestion	Stool culture.	Usually self-limiting.

Bacteria	Incubation	Signs and Symptoms	Duration	Associated Foods	Testing	Treatment
E. coli 0157:H7 & Shiga-toxin producing E. coli	1-9 days	Severe diarrhea that is watery but often becomes bloody, abdominal pain and vomiting, little or no fever present (usually), more common in children under four years old.	5-10 days	Undercooked beef, hamburger, unpasteurized milk or juice, raw fruits and vegetables, contaminated water, petting zoos.	Stool culture. 0157:H7 requires special culture media or PCR testing.	Supportive care. Monitor renal function, hemoglobin, and platelets closely. 0157:H7 can cause HUS. Antibiotics and antimotility agents may promote the development of HUS.

Bacteria	Incubation	Signs and Symptoms	Duration	Associated Foods	Testing	Treatment
Shigella	1-5 days	Abdominal cramps, fever, diarrhea. Stools may contain blood and mucus.	5-7 days	Food or water contaminated with human feces, daycare, fecal-oral route.	Routine stool cultures or PCR.	Supportive care. Azithromycin, ceftriaxone, or ciprofloxacin are first-line; ampicillin or TMP-SMX are alternatives (if susceptible). Intestinal perforation, toxic megacolon, reactive arthritis, and erythema nodosum can be sequelae.

Bacteria	Incubation	Signs and Symptoms	Duration	Associated Foods	Testing	Treatment
Yersinia	4-6 days	Abdominal cramps, right lower quadrant abdominal pain that may mimic appendicitis, diarrhea with or without blood.	10 days	Typically foodborne from raw/undercooked pork, unpasteurized milk, contaminated drinking water	Stool culture or PCR.	TMP-SMX is first-line; cefotaxime or ciprofloxacin are alternatives. Bacteremia and extra-intestinal manifestations may occur. Reactive arthritis and erythema nodosum can be sequelae.

Bacteria	Incubation	Signs and Symptoms	Duration	Associated Foods	Testing	Treatment
Vibrio	12-24 hours for non-cholerae; 2 hours-5 days for V. cholerae	Abdominal cramping, watery diarrhea (for V. cholerae, profuse diarrhea with "rice-water" stools).	1-7 days	Fecal-oral route, ingestion of untreated drinking water, raw/undercooked fish and shellfish, person-to-person transmission is rare.	Stool culture, PCR, or RDT	Doxycycline is first-line for V. cholerae; azithromycin, ceftriaxone, and ciprofloxacin are alternatives. Non-cholerae Vibrio species are usually self-limiting. If invasive, consider ceftriaxone plus doxycycline as first-line (an aminoglycoside plus TMP-SMX is alternative). Live-attenuated oral vaccine is available for disease prevention of V. cholerae.

Bacteria	Incubation	Signs and Symptoms	Duration	Associated Foods	Testing	Treatment
Enterotoxigenic E. coli	1-5 days	Watery diarrhea, abdominal cramps, some vomiting.	3-7+ days	Water or food contaminated with human feces.	Stool culture. ETEC requires special testing (PCR) for identification.	Supportive care, antibiotics rarely needed. TMP-SMX and quinolones recommended if indicated.

Bacteria	Incubation	Signs and Symptoms	Duration	Associated Foods	Testing	Treatment
Clostridioides difficile toxin	Can appear weeks after antibiotic cessation	Watery diarrhea that can progress to severe colitis/toxic megacolon	Variable	Fecal-oral route, often associated with antibotic use.	PCR combined with toxin testing; institutional algorithms should be followed.	Antibiotic cessation, supportive care. Oral vancomycin or fidaxomicin (preferred over metronidazole). Antibiotics not indicated for asymptomatic colonization.

Viral

Bacteria	Incubation	Signs and Symptoms	Duration	Associated Foods	Testing	Treatment
Norovirus and Sapovirus	12-48 hours	Nausea, vomiting (more prevalent in children), abdominal cramping, diarrhea (more prevalent in adults), fever, myalgia, headache.	1-3 days	Fecal-oral route and aerosolized vomit, contaminated food or water (shellfish), ready-to-eat foods. Highly contagious, common settings include cruise ships, daycares, and schools.	Clinical diagnosis, negative bacterial culture, stool negative for WBCs, PCR assays are available.	Supportive care, rehydration, good hygiene.

Bacteria	Incubation	Signs and Symptoms	Duration	Associated Foods	Testing	Treatment
Rotavirus and enteric Adenovirus	2-4 days	Vomiting, watery diarrhea, low-grade fever, temporary lactose intolerance.	3-8 days	Fecal-contaminated foods, fomites, ready-to-eat foods. Aerosol transmission may be possible	Identification of virus in stool via PCR immunoassay.	Supportive care. Severe diarrhea may require fluid and electrolyte replacement.

Bacteria	Incubation	Signs and Symptoms	Duration	Associated Foods	Testing	Treatment
SARS-CoV-2	2-14 days	Acute COVID-19, fever, chills, cough, dyspnea, fatigue, myalgia, headache, sore throat, congestion, nausea, vomiting, diarrhea. MIS-C - fever, abdominal pain, vomiting, diarrhea, rash, conjunctivitis.	Acute symptoms less than 2 weeks, prolonged symptoms may last months (fatigue, anosmia, dysgeusia).	Respiratory aerosols and droplets.	PCR or antigen testing of nasal swabs.	Supportive care, rehydration, airborne precautions.

Bacteria	Incubation	Signs and Symptoms	Duration	Associated Foods	Testing	Treatment
Hepatitis	28 days average	Diarrhea, dark urine, jaundice, flu-like symptoms (fever, headache, nausea, abdominal pain).	2 weeks-3 months	Shellfish, raw produce, contaminated drinking water.	Increase in ALT, bilirubin, positive IgM, anti-hepatitis A antibodies.	Supportive care, prevention with immunization.

Parasites

Bacteria	Incubation	Signs and Symptoms	Duration	Associated Foods	Testing	Treatment
Giardia lamblia	1-4 weeks	Diarrhea, stomach cramps, flatulence, weight loss.	2-4 weeks	Uncooked food, contaminated water (hiking or camping).	Stool examination for ova and parasites (may need three samples), antigen testing or immunoassay.	Tinidazole or nitazoxanide are first-line; metronidazole is an alternative.

Bacteria	Incubation	Signs and Symptoms	Duration	Associated Foods	Testing	Treatment
Cryptosporidium	1-11 days	Diarrhea (usually watery), stomach cramps, bloating, flatulence, nausea, fever.	Remitting and relapsing for weeks to months.	Uncooked or contaminated food, drinking water.	Specific examination of stool for cryptosporidium, may need to examine food or water. Immunoassay and PCR available.	Supportive care, self-limited, consider nitazoxanide if severe.

Bacteria	Incubation	Signs and Symptoms	Duration	Associated Foods	Testing	Treatment
Cystoisospora	1-2 days	Non-bloody diarrhea and crampy abdominal pain.	Variable	Travel to tropical climates, immunocompromised.	Examination of stool for oocysts, intestinal biopsy is sometimes required.	TMP-SMX is first-line; ciprofloxacin is second-line. TMP-SMX prophylaxis indicated for HIV patients with CD4 count <200/mm3

Bacteria	Incubation	Signs and Symptoms	Duration	Associated Foods	Testing	Treatment
Entamoeba histolytica	2-4 weeks	Diarrhea (often bloody), frequent bowel movements, lower abdominal pain, dissemination to liver and other organs can occur.	Maybe protracted (several weeks to months)	Uncooked food or contaminated water, travel to tropical climate/areas with poor sanitation, MSM.	Examination of stool for cysts and parasites (may need at least three samples), immunoassay or PCR. Serology for long-term infections.	Metronidazole

Fungi

Bacteria	Incubation	Signs and Symptoms	Duration	Associated Foods	Testing	Treatment
Microsporidia	Up to 3 weeks	Watery, non-bloody diarrhea, abdominal cramping. In chronic cases, dehydration and failure to thrive.	Typically 2 weeks	HIV infection, not on ART, immunocompromised, travel, extremes of age.	Stool testing or intestinal biopsy.	ART for patients with HIV. Enterocytozoon bieneusi and Vittaforma corneae are also treated with fumagillin (not available in the US); other strains treated with albendazole. Disseminated infection may occur.

Case Study

A two-year-old male presents to the ED with a two-day history of vomiting and diarrhea. The patient's mother reports that he began vomiting two days ago, followed by the onset of diarrhea later that day. The vomit is non-bilious, and the diarrhea is described as watery, occurring approximately six times per day. The mother has not noted any blood in the stool. She reports a decreased appetite and oral intake over the last 24 hours, promoting the visit. The mother reports a low-grade fever of 100.5 F (38.1 C) is obtained. Previously, the boy was healthy with a normal birth history and is up-to-date on vaccinations. The boy attends daycare, has no recent travels, and no one else is sick at home. On physical examination, the patient is tired-appearing but non-toxic. Heart rate is 130 beats per minute, respiratory rate is 24 breaths/min, and blood pressure is 90/55 mmHg. Mucous membranes appear dry, eyes are slightly sunken, capillary refill is three seconds, and skin turgor is decreased. The abdomen is non-distended, mildly tender throughout, and hyperactive bowel sounds are present.

Initial Actions and Primary Survey

As with any patient, the examination begins with the ABCs. Airway and breathing should be assessed for adequacy and intervened upon with endotracheal intubation and mechanical ventilation if the child demonstrates signs of respiratory failure. As part of the circulation evaluation, an assessment of hydration status can occur shortly after the physician arrives at the bedside. If the child exhibits signs of severe dehydration immediate resuscitation measures should be enacted. Full cardiac monitoring with pulse oximetry and frequent blood pressure assessment should be established. Intravenous (IV) access and crystalloid resuscitation is necessary for severe dehydration. Severely dehydrated children should receive 30 ml/kg bolus over one hour for infants < 12 months and over 30 minutes for children 12 months-five years. This should be followed by 70 ml/kg over five hours for infants <12 months and over 2.5 hours for children 12 months-years years. If IV access is unobtainable, intraosseous placement should be considered early in the management of the severely dehydrated patient. As soon as the severely dehydrated child can drink, they should receive oral rehydration solution (ORS) at 5 ml/kg/hr.

Symptoms Associated with Dehydration

Symptom	Minimal or no dehydration (<3% loss of body weight)	Mild-moderate dehydration (3-9% loss of body weight)	Severe dehydration (>9% loss of body weight)
Mental Status	Well; alert	Normal, fatigued or restless, irritable	Apathetic, lethargic, unconscious
Thirst	Drinks normally; might refuse liquids	Thirsty, eager to drink	Drinks poorly; unable to drink
Heart Rate	Normal	Normal to increased	Tachycardia, with bradycardia in most severe cases
Quality of Pulses	Normal	Normal to decreased	Weak, thread, impalpable
Breathing	Normal	Normal; fast	Deep
Eyes	Normal	Slightly sunken	Deeply sunken
Tears	Present	Decreased	Absent
Mouth and Tongue	Moist	Dry	Parched
Skinfold	Instant recoil	Recoil under two seconds	Recoil over two seconds
Capillary Refill	Normal	Prolonged	Prolonged; minimal
Extremities	Warm	Cool	Cold; mottled; cyanotic
Urine Output	Normal to decreased	Decreased	Minimal

Presentation

The clinical presentation of patients with acute gastroenteritis is variable depending on the pathogen and the amount of inoculum the patient is exposed to. The most common symptoms are nausea and vomiting followed shortly after by diarrhea. Diarrhea may be watery, as is often the case with viral causes and toxin-producing bacteria. Invasive bacteria such as Campylobacter, Shigella, Salmonella, and enteroinvasive E. coli (shiga-toxin producing) will often produce bloody diarrhea. Regarding parasitic causes of gastroenteritis, Entamoeba may be associated with bloody diarrhea while large amounts of flatulence could suggest infection with Giardia. Many causative organisms of gastroenteritis have associated symptoms that may include fever and abdominal cramping. If there is a prolonged or severe course of illness dehydration, weight loss and malnutrition may occur.

If the infectious agent produces a preformed toxin, such as S. aureus or B. cereus, vomiting and diarrhea will occur in a matter of hours after ingestion of contaminated food. In the case of most bacterial pathogens, the incubation period will be two to five days. Viral illnesses have an incubation period of 12 hours to three days, and parasitic agents may take two days to four weeks to manifest symptoms. Exposure of a traveler or hiker to untreated water and illness that persists for more than seven days should prompt evaluations for protozoal pathogens. One of the major clinical features of protozoal diarrheas is a prolonged course. Patients who have persistent diarrhea should have stools tested for Entamoeba histolytica antigen, Giardia intestinalis antigen, and Cryptosporidium parvum antigen by enzyme immunoassay (EIA) or PCR.

Upon the initial evaluation of the child presenting with acute vomiting or diarrhea, obtaining a history focused on the onset of symptoms, the number of emesis and diarrhea episodes, presence of bilious vomiting or hematemesis, melena or hematochezia, fever, presence of pain, and any associated symptoms will be helpful in clinically diagnosing acute gastroenteritis. Further history eliciting possible sick contacts, exposure to contaminated food or water, travel history, immunocompromised status, recent antibiotic use, and sexual history may prove helpful. Clues to the child’s hydration status can also be gained from the parents by way of the history. Asking questions regarding the patient’s behavior or activity level, oral intake, and the number of wet diapers or voids since the onset of symptoms can suggest if he or she is still adequately hydrated.

Like the history, a careful physical examination can help narrow the differential diagnosis. While a complete physical examination should be performed on every pediatric patient, in the case of acute gastroenteritis, the most useful components of the exam will come from the child’s general appearance (looking for lethargy), vital signs (including tachycardia and hypotension), and general appearance assessing for any signs of dehydration (including dry mucous membranes, delayed capillary refill, sunken eyes, and skin tenting). The abdomen should also be assessed for distension, bowel activity, tenderness, and rigidity that may prompt further consideration of other causes of the child’s acute vomiting or diarrhea, if abnormal. In the case of gastroenteritis, the abdomen should be relatively benign with physical exam findings commonly being some mild diffuse tenderness and hyperactive bowel sounds.

Diagnostic Testing

Serum laboratory studies may not be necessary for the child who presents with acute gastroenteritis unless they are severely dehydrated. If the child appears moderately or severely dehydrated, a basic metabolic profile and glucose measurement may help guide management by assessing for electrolyte imbalance (hyponatremia, hypernatremia, or hypokalemia), dehydration (metabolic acidosis), acute renal failure, or hypoglycemia. Infants have a relatively high glucose requirement and low glycogen stores, so they may develop hypoglycemia when energy requirements rise. Checking blood sugar can be especially important in this population.

Stool cultures and specific pathogen testing are usually not necessary in the well-appearing child who is bound for discharge, and the results will require some time to return. Stool samples should be obtained for any child exhibiting symptoms suggestive of invasive diarrhea, such as blood or mucous in stool, if they are started on antibiotic therapy, hospitalized, or immunocompromised. Common stool studies include bacterial stool culture, assessment for stool leukocytes, and occult blood. Certain culture medium may be required for select pathogens such as Salmonella, Shigella, and E. coli O157:H7. If there has been recent antibiotic use and symptoms are severe, assessment for C. difficile toxin and PCR should also be considered, and institutional protocols should be followed for testing. Some cases of infectious diarrhea, such as E. coli O157:H7 and hepatitis A, require reporting to public health departments. Clinicians should be aware of the reporting guidelines for communicable diseases for their practice location.

Making a Diagnosis

Gastroenteritis is largely a clinical diagnosis, though the identification of a specific organism (in severe, non-self-limiting cases) may involve diagnostic testing. Clinicians should consider alternate diagnoses in children with isolated vomiting in the absence of diarrhea, though it should be noted that vomiting can precede diarrhea in cases of gastroenteritis.

Treatment

As described above, treatment begins with the initial assessment and resuscitation of the child if they show signs of severe dehydration. If the child appears to be only mildly or moderately dehydrated, a trial of an antiemetic such as ondansetron (available as a liquid or orally dissolving tablet) may be attempted to facilitate oral rehydration. The fluid of choice for oral rehydration therapy should be an isotonic solution that includes water, sodium, chloride, glucose, and bicarbonate. There are various formulations available the most common being Pedialyte. The World Health Organization also publishes guidelines on the production and administration of ORS. Care should be taken to avoid hypotonic (pure water) or hypertonic (broth) solutions as these can lead to hypernatremia or hyponatremia, especially in younger children and infants. Total intake should be 30-50 ml/kg for the mildly dehydrated child and 60-80 ml/kg for the moderately dehydrated child, with 25% of the goal intake administered each hour for four hours while being observed in the ED.

Empiric antimicrobial therapy is often not required for the child presenting with gastroenteritis. Antibiotic therapy does not usually decrease the duration of symptoms and may cause further complications for the child. Consideration for antimicrobial therapy should be made if bloody diarrhea is present, the likelihood for complications is high (age < one year, immunosuppression, septicemia, or chronic disease), hospitalization, or if stool cultures suggest a specific bacterial pathogen where antibiotic treatment would be of benefit. If the history supports parasitic infection, antimicrobial therapy should be considered as well.

Antidiarrheal or antimotility compounds are not recommended for children with gastroenteritis as they may prolong infection or cause complications due to an accumulation of bacterial toxins if present. Probiotics and zinc supplementation are gaining favor in the management of acute gastroenteritis as they may decrease the duration of illness. The Infectious Diseases Society of America (IDSA) acknowledges that while probiotics may be of benefit, there is significant heterogeneity in the literature as to which probiotics, doses, and duration are most effective. Systematic review and meta-analysis data suggest that S. boulardii combined with zinc may be the most effective supplement combination. Smectite and symbiotics combined with zinc may also be beneficial for diarrhea reduction in acute gastroenteritis. One caveat is that zinc supplementation may only be beneficial in children ages six months-five years who are at risk for malnutrition or live in a country with a high prevalence of zinc deficiency. Thus, the decision to prescribe zinc should be considered on a case-by-case basis. Diluted milk, kaolin-pectin, micronutrients, prebiotics, and vitamin A have not shown benefit for diarrhea reduction.

Emergency Department Disposition

Most cases of mild to moderate gastroenteritis can be managed on an outpatient basis given the child can maintain hydration. The child should be observed in the ED for a period of time to ensure tolerance of oral intake. The child may benefit from a short course of antiemetics on an outpatient basis to avoid vomiting while hydrating. Aggressive parental education on rehydration as well as monitoring for signs of dehydration is key prior to discharge. They should be encouraged to follow up with their pediatrician in two-three days for reassessment and return to the ED for any concerns of worsening or inability to stay hydrated. If there is any concern for deterioration of the patient’s clinical status or the inability to perform oral rehydration after a short course of observation, the child should be admitted to the hospital for observation and IV fluids.

Pearls and Pitfalls

To make the diagnosis of gastroenteritis, the child should have elements of both vomiting and diarrhea.
Misdiagnosing more severe medical conditions such as gastroenteritis can lead to further morbidity or mortality.
The mainstay of treatment is rehydration, with oral rehydration being preferred if the child is able.
Stool cultures should be obtained in children presenting to the ED with diarrhea whose symptoms are severe, if they are immunocompromised, or who have blood and mucus in their stool.
Antibiotics are not helpful in most cases of pediatric gastroenteritis, unless there is no clinical improvement and stool cultures are positive.

Case Study Resolution

The patient was determined to be moderately dehydrated, most likely secondary to viral gastroenteritis. Ondansetron oral disintegrating tablet (ODT) was administered and oral rehydration was provided. The patient was observed for four hours and was able to tolerate liquids towards the end of the visit. Diagnostic testing was determined to not be required. The mother was counseled on home care and continued use of prescribed ondansetron ODT at home. Return red flags including worsening appearance or lethargy, uncontrolled vomiting, persistent fevers, bloody stools, increasing abdominal pain, or any other concerns were discussed. The mother was encouraged to have the child follow up with his pediatrician in two-three days if the patient's symptoms continued.

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