Diarrhea

Traditional Approach:

Secretory — poisoned mucosal villi — “the sieve”

Cytotoxic — destroyed mucosal villi — “the shred”

Osmotic — malabsorption — “the pull”

Inflammatory — edema, motility — “the push”

Lots of overlap, difficult to apply to clinical signs and symptoms.

Bedside Approach:

Fever/No Fever, Bloody/No Blood

Non-bloody, febrile — most likely viral

Non-bloody, afebrile — may be viral

Bloody, febrile — likely bacterial

Bloody, afebrile — full stop. Eval for Hemolytic Uremic Syndrome

Workup

Ask yourself — again — why is this not… appendicitis-torsion-intussusception-etc.

Admit sick children, but most go home, so…

Non-bloody, febrile — no workup necessary; precautionary advice

Non-bloody, afebrile — be more skeptical, but generally same as above

Bloody, febrile — stool culture, follow up; do not treat empirically unless septic and admitted. Culture will dictate treat/no treat/how.

Bloody, afebrile — evaluate for hemolytic uremic syndrome, especially if under 5 years old: CBC, chemistries, UA, stool culture

Evaluate Hydration Status

Selected References

American Academy of Pediatrics. Clostridium difficile Infection in Infants and Children. Committeee on Infectious Diseases. Pediatrics. 2013; 131 (1) 196-200

Khan WA et al. Central Nervous System Manifestations of Childhood Shigellosis: Prevalence, Risk Factors, and Outcome. Pediatrics. 1999 Feb;103(2):E18

Lee JY et al. Diagnostic yield of stool culture and predictive factors for positive culture in patients with diarrheal illness. Medicine (Baltimore). 2017 Jul; 96(30): e7641.

Meropol SB et al. Yield From Stool Testing of Pediatric Inpatients. Arch Pediatr Adolesc Med. 1997 Feb;151(2):142-5.

Nelson JD et al. Treatment of Salmonella gastroenteritis with ampicillin, amoxicillin, or placebo. Pediatrics 1980; 65:1125.