gastroenteritis%20-%20viral
GASTROENTERITIS - VIRAL
Acute gastroenteritis is a diarrheal disease of rapid onset.
Viruses are one of the common causes of acute gastroenteritis.
Rotavirus, norovirus/"Norwalk-like" virus, sapovirus, enteric adenovirus serotypes 40 and 41, astrovirus, calicivirus and enterovirus are the established viral agents causing gastroenteritis.
Rotavirus is the most common pathogen causing diarrhea in patients 3-24 months old.
Patients <3 months old are protected by maternal rotavirus antibodies that are passed transplacentally and possibly by breastfeeding.
Transmission is through fecal-oral route.

Supportive Therapy

Oral Rehydration Solution (ORS)

  • The formula recommended by the World Health Organization (WHO)
    • Concentration of: 75 mEq/L sodium, 75 mmol/L glucose with total osmolarity of 245 mOsm/L, or ½ teaspoon of salt and 6 teaspoons of sugar in 1 L of water
    • Lower osmolarity that is proportionally reduced sodium and glucose concentrations
    • The formulation has been shown to reduce vomiting and the need for intravenous (IV) fluids
  • The WHO-recommended amount to be given based on weight and age are as follows:

  • Weight Age Amount (within the first 4 hours)
    <5 kg (11 lb) <4 months 200-400 mL
    5-7.9 kg (11 lb -17 lb, 7 oz) 4-11 months 400-600 mL
    8-10.9 kg (17 lb, 10 oz - 24 lb) 12-23 months 600-800 mL
    11-15.9 kg (24 lb, 4 oz - 35 lb) 2-4 years 800-1200 mL
    16-29.9 kg (35 lb, 4 oz - 65 lb, 15 oz) 5-14 years 1200-2200 mL
    ≥30 kg (≥66 lb, 2 oz) ≥15 years 2200-4000 mL

  • Preferred 1st-line treatment in children with mild to moderate dehydration for replacement of fluid and electrolytes
  • As effective as IV fluids in rehydrating patients with mild to moderate dehydration
  • Severe vomiting, abdominal ileus and in state of hemodynamic shock are contraindications to ORS

Intravenous (IV) Fluids or Nasogastric (NG) ORS

  • Given for 4-6 hours or until adequate hydration is achieved
  • IV fluids are recommended in the following patients:
    • Severely dehydrated
    • In whom oral hydration has failed due to severe vomiting
    • Patients with intestinal ileus or intestinal obstruction
    • Patients in shock or altered mental status
  • NG ORS may be given to moderately dehydrated patients who cannot tolerate oral administration of ORS and to children who are too weak and refuse to drink which may cause insufficient hydration if only by oral intake 
  • NG feeding allows continuous ORS administration at a slow and steady amount
  • Rehydrated state should be maintained by continuous replacement of losses

Mild Dehydration

  • Administer 50-100 mL of ORS to children <2 years old, 100-200 mL to children 2-10 years old, or unlimited amount for children >10 years old, after each loose stool, or 20 mL/kg body weight/hour to replace estimated fluid deficit
  • Several trials support the use of NG ORS feeding even in patients with continuous vomiting or with presence of oral ulcers
  • Continue breastfeeding during diarrhea or resume age-appropriate feeding as soon as rehydration is complete
  • Rapid IV hydration may also be administered

Moderate to Severe Dehydration

  • Start patient on rapid IV rehydration
  • Administer 20 mL/kg body weight of IV lactated Ringer’s solution or normal saline solution (0.9% NaCl) until pulse, perfusion and mental status return to normal, followed by 100 mL/kg body weight of ORS for 4 hours or 5% dextrose ½ normal saline IV at 2x maintenance fluid rates
    • Alternatively, give 100 mL/kg body weight. Then, for infants <1 year old, give 30 mL/kg/body weight within the 1st hour, followed by 70 mL/kg/body weight within 5 hours. For children >1 year old, 30 mL/kg/body weight IV fluid may be given within the 1st 30 minutes, followed by 70 mL/kg/body weight within 2.5 hours
    • Administration of ORS should be started once patient’s condition stabilizes; it may also encourage early resumption of feeding
    • Study shows that giving of ORS may lead to rapid resolution of acidosis compared to IV fluid
Editor's Recommendations
Special Reports