Makindo Medical Notes

💧 Key point: Assess clinical state carefully. Rehydration is the cornerstone of management. Altered bowel habit may suggest colorectal cancer. Causes are mainly infective, ischaemic, and malignant — clinical context is key.

📌 About

• Increased stool output >200 g/day.
• Increased stool fluid content and frequency.
• Chronic diarrhoea: duration >3 weeks.
• Steatorrhoea: >7 g fat/day in stools on a high-fat diet.

⏱️ Types of Diarrhoea

• Acute: sudden onset, <14 days (usually infective, IBD flare, drug-induced).
• Persistent: 14–30 days.
• Chronic: >30 days (often malabsorption, IBD, neoplastic, functional).

🦠 Causes

• Acute: Infective (bacterial, viral, parasitic), IBD, IBS, overflow, antibiotic-associated, C. difficile, thyrotoxicosis, laxatives, alcohol, drugs (NSAIDs, PPIs, chemotherapy).
• Persistent/Chronic: Giardia, E. histolytica, C. difficile, malabsorption, neoplasia, chronic IBD.

⚠️ Known IBD – Exclude Coexisting Infection

🟢 Mild Colitis (<4 stools/24 hr)

• Apyrexial, HR <90/min, Hb >120 g/L, ESR <10 mm/hr, small blood in stool.
• Known IBD: steroid enemas.
• Uncertain diagnosis: await histology & stool cultures; consider flex sigmoidoscopy or colonoscopy.
• DVT prophylaxis if appropriate (exclude coagulopathy first).

🔴 Severe Colitis (>8 stools/24 hr)

• Febrile >37.5°C, HR >100/min, Hb <110 g/L, ESR >30 mm/hr, blood +++ in stool.
• Inform GI registrar urgently.
• Investigations: AXR, sigmoidoscopy, stool cultures.
• Treatment: IV methylprednisolone 60 mg/24 hr (infusion) or hydrocortisone 100 mg IV QDS. Add DVT prophylaxis as per local policy.

🔍 Investigations

• FBC, U&E, LFTs, ESR, CRP.
• Endomysial antibodies, haematinics if coeliac suspected.
• Faecal calprotectin to differentiate IBD vs IBS.
• Stool cultures, C. difficile toxin (esp. if recent antibiotics).
• Ova, cysts, parasites (3 samples if risk factors).
• Blood cultures if febrile/septic.
• Plain AXR for toxic megacolon/obstruction.
• Rectal exam, sigmoidoscopy, rectal biopsy.
• Thyroid function tests.
• Always document travel history & food exposures on lab requests.

🩺 Clinical Features

• Watery stools ± mucus.
• Abdominal cramping pain.
• May be associated with fever, dehydration, or systemic upset.

📋 Common Causes – with Clinical Patterns

• Bacterial gastroenteritis: watery/bloody diarrhoea, fever, abdo pain. Confirm with stool culture/PCR. Supportive; antibiotics in severe/prolonged cases (e.g., ciprofloxacin for Campylobacter).
• Viral gastroenteritis: norovirus/rotavirus. Watery stools, nausea, vomiting. Supportive, rehydration.
• Parasitic infections: Giardia, E. histolytica, Cryptosporidium. Steatorrhoea, weight loss. Dx by stool microscopy/antigen. Rx: metronidazole (Giardia/Entamoeba), nitazoxanide (Crypto).
• C. difficile: post-antibiotics, watery/bloody stools, fever. Dx stool toxin/PCR. Rx: stop antibiotics, oral vancomycin/fidaxomicin.
• IBD: chronic diarrhoea, blood, weight loss. Dx: colonoscopy, faecal calprotectin. Rx: 5-ASA, steroids, biologics.
• Food poisoning: S. aureus, Bacillus cereus. Acute vomiting/diarrhoea post ingestion. Supportive.
• Lactose intolerance: bloating, diarrhoea post dairy. Dx: H₂ breath test. Rx: avoid lactose, lactase supplements.
• Coeliac disease: chronic diarrhoea, weight loss, anaemia. Dx: anti-tTG/EMA + biopsy. Rx: gluten-free diet.
• Medication-related: antibiotics, metformin, chemo, laxatives. Stop offending drug.
• HIV-related diarrhoea: opportunistic infections (Crypto, CMV). Chronic, weight loss. Dx: stool PCR, colonoscopy. Rx: targeted antimicrobial + ART.
• GVHD (post-transplant): chronic diarrhoea, abdo pain. Dx: biopsy. Rx: immunosuppression.
• IBS (diarrhoea-predominant): intermittent, cramps, bloating. No red flags. Dx: Rome IV. Rx: diet (low FODMAP), antispasmodics.
• Ischaemic colitis: elderly/vascular disease. Sudden pa