Pediatric Infectious Diarrhea

Pt with no h/o inflammatory bowel disease and no recent infections/hospitalizations presents with acute onset diarrhea. Reports fever, N/V, abdominal pain. Recently returned from international vacation; family went swimming and consumed shellfish, raw milk, unpasteurized juice, undercooked meats/fish/eggs, and uncooked produce while abroad. Fever, dry mucous membranes, abdominal pain, joint pain, erythema nodosum on exam.

  • Labs

    • Obtain CBC, CMP

    • Obtain U/A to r/o HUS

    • Bloody stools with fever: Evaluate stool culture for Yersinia, Campylobacter, Salmonella enterica, Shigella, STEC

    • Pt > 2 y/o with exposure to abx within previous 12 weeks: Obtain C. difficile PCR

    • Diarrhea lasting > 14 days: Evaluate for parasitic infection

    • Pt with h/o AIDS: Obtain stool cultures for cryptosporidium, Cyclospora, Cystoisospora, microsporidia, Mycobacterium avium complex, and cytomegalovirus

  • Treatment

    • Maintain hydration: Recommend electrolyte maintenance solution (see notes for recipe) and/or apple juice mixed half-and-half with water

    • Pt younger than 3 months with recent international travel, fever ≥ 100.4°F, abdominal pain, suspected shigella infection: Start empiric azithromycin 10 mg/kg qd x 3 days (max/adult dose = 500 mg)

  • Parents advised that infectious diarrhea is generally self-limited

Notes

  • Etiology

    • Report any diarrhea potentially caused by food or water-borne illness to identify possible outbreaks

    • Post-infectious irritable bowel syndrome due to recent infection should be considered and ruled out

  • Bloody diarrhea

    • Bloody diarrhea mnemonic: You're Constantly SShitting Erythrocytes (Yersinia, Campylobacter, Salmonella/Shigella, E. coli)

    • STEC: Shiga toxin-producing E. Coli

  • Physical Exam

    • Assess patient's volume status on exam to identify possible dehydration, e.g. mucous membranes

    • Extraintestinal and/or post-infectious manifestations may include reactive arthritis, erythema nodosum, or glomerulonephritis

  • Treatment

    • Oral rehydration therapy recipe: Mix 6 teaspoons sugar + 1/2 teaspoon salt in 1 liter of water and boil; allow to cool before consumption

    • See JAMA article: Electrolyte maintenance solution vs. dilute apple juice

    • IDSA Criteria for Empiric Antibiotic Therapy

      • Pt < 3 m/o with suspected bacterial etiology

      • Suspected Shigella infection with abdominal pain and documented fever ≥ 100.4°F (38°C)

      • Recent international travel with temperature ≥ 100.4°F (38°C) and/or s/sx sepsis