Onset & Duration: When did the colour change start? Persistent or intermittent?
Stool Characteristics: Colour, consistency (loose, hard, bulky), presence of blood/mucus.
Associated Symptoms: Abdominal pain, bloating, diarrhoea, constipation, jaundice, fatigue, weight loss.
Dietary Factors: Recent foods (beetroot, spinach, food dyes), iron supplements, travel history.
Medical History: Hepatobiliary disease, IBD, coeliac, pancreatitis, medications (antibiotics, antacids, iron).

🩺 2. Physical Examination

General: Look for jaundice, pallor, dehydration, cachexia.
Abdomen: Distension, tenderness, hepatosplenomegaly, abnormal bowel sounds.
Rectal Exam: Stool colour/consistency, check for blood.

🔬 3. Investigations

Stool Tests: FOBT, stool culture, faecal fat, calprotectin/lactoferrin.
Blood Tests: CBC, LFTs, amylase/lipase, renal profile, electrolytes.
Imaging: Abdominal US/CT, endoscopy/colonoscopy if bleeding suspected.

🎨 4. Stool Colour – Causes & Clinical Notes

⚫ Black (Melaena): - Upper GI bleed (ulcer, varices, gastritis) → black, tarry stool, anaemia, dizziness. - Non-pathological causes: iron, bismuth meds.
🔴 Red (Haematochezia): - Lower GI bleed (haemorrhoids, diverticulosis, colorectal cancer, IBD). - Bright red blood on tissue = likely anal fissure/haemorrhoids. - Urgent eval if persistent or with weight loss.
⚪ Pale/Clay-Coloured: - Biliary obstruction (gallstones, cholestasis, biliary atresia). - Hepatic disease (hepatitis, cirrhosis). - Often with jaundice, dark urine, pruritus.
💛 Yellow/Greasy (Steatorrhoea): - Fat malabsorption (coeliac, chronic pancreatitis). - Giardiasis or excess dietary fat. - Foul-smelling, floating stools with weight loss.
🟩 Green: - Rapid gut transit (gastroenteritis, IBS). - Green leafy vegetables, iron supplements, food dyes. - Usually benign if transient.
⚪ White/Chalky: - Barium after imaging. - Bile duct obstruction or severe hepatobiliary disease. - Needs correlation with jaundice and hepatology work-up.

🛠️ 5. Management

Treat underlying cause: - Infections → antibiotics/antiparasitics. - GI bleed → PPI, endoscopy, surgery if severe. - Malabsorption → gluten-free diet (coeliac), enzyme replacement (pancreatitis). - Obstruction → surgical/endoscopic relief.
Medication Review: Adjust or stop contributing drugs (iron, antacids, antibiotics).
Dietary Advice: Explain benign food-related changes (beetroot, spinach, supplements).
Follow-Up: Monitor patients with chronic GI/hepatobiliary disease or unexplained persistent colour changes.

💡 Clinical Pearls

Persistent black or red stools → always exclude GI bleeding 🚨.
Pale stools + dark urine + jaundice → think obstructive jaundice.
Yellow greasy stools → suspect malabsorption (esp. coeliac, pancreatic insufficiency).
Green stools in children are often dietary or viral – usually benign.

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Change in stool colour

🧾 1. Clinical History

🩺 2. Physical Examination

🔬 3. Investigations

🎨 4. Stool Colour – Causes & Clinical Notes

🛠️ 5. Management

💡 Clinical Pearls

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