Pediatrics: Diarrhea in Children

Definition of Diarrhea

• Diarrhea is the loss of more than 10ml/kg/day of fluid through stool.
• In breastfed babies, it's an increase in consistency, volume, and frequency of stool relative to their usual habits.
• In bottle-fed babies, it's three or more loose stools per day.

Clinical Types of Diarrhea

• Acute diarrhea: lasts for less than 14 days.
• Persistent diarrhea: begins as acute and lasts for 14-28 days.
• Chronic diarrhea: lasts for more than 28 days.
• Dysentery diarrhea: diarrhea with visible blood in stools.

Epidemiology and Etiology

• Diarrhea constitutes 25-30% of deaths in children below 5 years of age.
• The age incidence is between 3 months to 5 years, with a peak at 6-12 months.
• It's common in summer and autumn, but less in winter and spring.

Risk Factors for Diarrhea

• Host factors:
  • Age
  • Inadequate breast-feeding
  • Malnutrition
  • Measles infection
  • Vitamin A deficiency
  • Milk protein allergy
  • The use of oral antibiotics
  • Immunosuppression
• Behavioral factors:
  • Using contaminated feeding formula or water
  • Improper sewage disposal
  • Poor sanitary conditions
  • Day care centers

Pathophysiology of Diarrhea

• Secretory diarrhea:
  • Intestinal cells actively secrete due to secretagogues (e.g., cholera toxin)
  • Rapid development of dehydration
  • Electrolyte imbalance
• Invasive diarrhea:
  • Microbes invade intestinal mucosal cells
  • Blood and mucus in stool
  • Septicemia
  • Intestinal perforation
  • Toxic megacolon
  • HUS
• Osmotic diarrhea:
  • Ingested solutes poorly absorbed
  • Dehydration
  • Hypernatremia
• Motility disorders:
  • Increased gut motility
  • Decreased transit time
  • Malnutrition
• Decreased surface area:
  • Decreased solute absorption and transit time
  • Malnutrition (Short gut syndrome)

Differential Diagnosis of Diarrheal Disorders

• Infective diarrhea:
  • Primary GIT infection (GE)
  • Secondary (parenteral diarrhea)
  • Watery offensive for 2-4 days, then bloody with campylobacter
• Non-infective diarrhea:
  • Lactose intolerance
  • Enterohemorrhagic E coli
• Viral diarrhea:
  • Low-grade fever
  • Vomiting followed by copious watery diarrhea
  • Non-foul-smelling stool
  • Symptoms persisting for 3-8 days (intestinal flu)

Assessment of Dehydration

• Item No dehydration Some dehydration Severe dehydration
• Mental status Well, alert Restless, irritable* Lethargy, unconscious*
• Eye Normal Sunken Very sunken, dry cornea
• Tears Present Absent Absent
• Mouth and tongue Moist Dry Very dry
• Thirst (oral intake) Drinks normal Drinks eagerly* Poor or unable to drink*
• Skin pinch Goes back quickly Goes back slowly* Goes back very slowly*

Treatment Plan

• Plan A, Plan B, and Plan C are used to manage dehydration based on the severity of dehydration.