II. Epidemiology
- 
                          Incidence
                          - U.S. Outpatient Visits: 1.5 Million per year
- U.S. Hospitalizations: 200,000 per year
- Deaths- U.S.: 300 per year
- World: 2.5 Million per year (age under 5 years)- Fifth leading cause of death in children worldwide)
 
 
 
III. Definitions: Diarrhea
- See Pediatric Vomiting
- 
                          General- See Diarrhea
- Sudden increased stool frequency and looseness
- Three or more watery or loose stools per day
 
- Types- Non-Inflammatory Diarrhea- Watery stools without blood or mucus
- Small Intestine involvement without mucosa destruction
 
- Inflammatory Diarrhea- Bloody stools with mucus (Stool Leukocytes)
- Large Intestine involvement
- Associated with fever, vomting and abdominal tenderness
 
 
- Non-Inflammatory Diarrhea
- Severe Diarrhea by frequency (inaccurate, use degree of Dehydration status to grade severity)
- Green Stools- Suggests very rapid transit
- Seen in moderate to severe Diarrhea
 
IV. Causes
- See Infectious Diarrhea Causes
- 
                          Viruses (75-90% of cases)- Rotavirus (most common)- Fever in 50% of cases
- Age 5 years most typically affected
- Most cases occur in winter
- Fecal Leukocytes present in 12% of cases
 
- Norovirus or Norwalk Virus- No associated fever
- Occurs November to April in 80% of cases
 
- Enteric Adenovirus
- Astrovirus
 
- Rotavirus (most common)
- 
                          Bacteria (10-20% of cases, especially Inflammatory Diarrhea)- Escherichia coli- Accounts for 10% of Bacterial Diarrhea
- Fever in 20% of cases
- Most common in Summer
 
- Campylobacter jejuni- Fever in 80% of cases
- Occurs all year but peaks in July
- Bloody Diarrhea with Fecal Leukocytes
 
- Salmonella- Bloody Diarrhea
 
- Shigella- High fever (and Febrile Seizures)
- Bloody Diarrhea
 
- Yersinia enterocolitica
- Clostridium difficile
 
- Escherichia coli
- 
                          Parasites (<5%, especially cases lasting >14 days)- Giardia lamblia- No associated fever
 
- Cryptosporidium- Associated with fever
 
 
- Giardia lamblia
V. History
- Onset and Duration of Diarrhea
- Fever and associated symptoms
- Emesis Frequency and character
- 
                          Stool Frequency and Character- Watery stools
- Foamy stools
- Bloody stools
 
- Urinary output (minimums listed below)- Infant: Three or more times per day
- Child: Two or more times per day
 
- Feeding history- Oral Rehydration Solution use prior to evaluation
 
- Mental status (Behavior and activity)
- Recent Medications- Antibiotics in the last 3 months
 
- Possible ingestions
- Contagious contacts
- Recent travel
- Pet exposure
VI. Symptoms: Red Flags
VII. Signs
VIII. Differential Diagnosis
- Gastrointestinal causes
- Extra-Intestinal causes
IX. Labs
- See Pediatric Dehydration
- Labs are not indicated in most cases of mild to moderate Diarrhea
- Indications- Severe Diarrhea or Inflammatory Diarrhea (blood, mucous)
- Moderate to severe Dehydration
- Immunocompromised
- Suspected Sepsis
 
- Basic chemistry panel- Serum Sodium
- Serum Potassium
- Serum Glucose
- Serum Creatinine
- Serum bicarbonate- Level >15 mEq/L correlates with <5% Dehydration
 
 
- Fecal specimen tests (consider when specifically indicated)- Stool Ova and Parasites (and GiardiaAntigen)- Consider for persistent or recurrent Diarrhea lasting longer than 2 weeks
- Consider for travel to endemic regions
 
- Clostridium difficile Toxin B- Consider if recent Antibiotics or other Clostridium difficile risk factors
 
- Rotavirus- Define start of an epidemic
- Define the cause when considering more serious possibilities
 
- Direct fecal smear for Stool Leukocytes- Rarely indicated
- Gross blood or Fecal Occult Blood has similar sensitivity for Inflammatory Diarrhea
 
- Stool enteric pathogen PCR or NAT panel (specific organisms included varies by manufacturer)
- Stool Culture- Rarely indicated due to low Test Sensitivity
 
 
- Stool Ova and Parasites (and GiardiaAntigen)
X. Management
XI. Prevention
- See Water Disinfection
- See Traveler's Diarrhea Prevention
- See Foodborne Illness Prevention
- 
                          Rotavirus Vaccine (Rotarix, RotaTeq)- Safe, effective oral Live Vaccine
- Three dose Vaccine part of the Primary Series in the first year of life in the United States
 
