Select stool pattern (>2‑3 weeks), growth parameters, abdominal pain, perianal disease, extraintestinal signs, and lab clues → differentiate toddler's diarrhea, celiac disease, IBD, giardia, cystic fibrosis, food allergy, and protein‑losing enteropathy.
⚠️ Red flags: weight loss, perianal disease, nocturnal diarrhea, occult blood → prompt endoscopic evaluation.
Select stool consistency (loose, greasy, bloody), growth (FTT, weight loss), perianal disease, extra‑intestinal signs (rash, arthritis), and age → system suggests toddler's diarrhea, celiac disease, IBD (Crohn/UC), cystic fibrosis, giardia, or food protein allergy, and recommends labs (fecal calprotectin, celiac panel, sweat test, endoscopy).