Gastroenteritis - Viral

Definition

Viral gastroenteritis in children is an acute inflammation of the stomach and intestines caused by viruses, leading to diarrhea, vomiting, abdominal pain, and sometimes fever, typically self-limiting.

Epidemiology

• Most common cause of acute diarrhea in children worldwide
• Peak incidence in children under 5 years of age
• Rotavirus is the leading cause of severe pediatric gastroenteritis globally
• Norovirus is a common cause of outbreaks in daycare and school settings
• Transmission occurs via fecal-oral route, contaminated food/water, and close contact

Etiology

• Rotavirus (most severe in infants and young children)
• Norovirus (common in outbreaks and older children)
• Adenovirus types 40 and 41
• Astrovirus
• Sapovirus
• Mixed viral infections in immunocompromised children

Pathophysiology

• Viruses infect and damage enterocytes lining the small intestine
• Loss of absorptive surface leads to malabsorption and osmotic diarrhea
• Enterotoxins or viral proteins may stimulate secretory diarrhea
• Altered intestinal motility contributes to vomiting and cramping
• Immune response generates fever and systemic symptoms
• Most infections are self-limited, but severe dehydration can occur