350.2 🩺 國考版

350.2.1 高頻考點

350.2.1.1 IBS Rome IV

  • ≥ 1 day/week abdominal pain × 3 months
  • 2+ of: defecation-related, stool frequency change, stool form change
  • Subtypes: D, C, M, U

350.2.1.2 Alarm Features (Workup)

  • ≥ 50 yo new onset
  • Weight loss
  • Hematochezia
  • Anemia
  • Family history GI cancer
  • Nocturnal symptoms

350.2.1.3 Workup (No Alarms)

  • CBC, BMP
  • Fecal calprotectin (IBD vs IBS)
  • Celiac serology
  • TSH

350.2.1.4 Pathophysiology Multifactorial

  • Visceral hypersensitivity
  • Altered motility
  • Altered microbiome
  • Low-grade inflammation
  • Brain-gut axis
  • Psychosocial
  • Post-infectious

350.2.1.5 Treatment IBS-C

  • PEG (laxative)
  • Linaclotide (Linzess, GC-C)
  • Lubiprostone (Amitiza, ClC-2)
  • Plecanatide (Trulance, GC-C)
  • Tenapanor (Ibsrela, NHE3 inhibitor)
  • Prucalopride (Motegrity, 5-HT4 agonist)

350.2.1.6 Treatment IBS-D

  • Loperamide (symptomatic)
  • Rifaximin (Xifaxan, 14-day course)
  • Eluxadoline (Viberzi, avoid pancreatitis/cholecystectomy history)
  • Alosetron (Lotronex, women, REMS)
  • Bile acid sequestrants if bile acid diarrhea

350.2.1.7 Pain Management

  • TCAs (amitriptyline 10-25 HS) — IBS-D especially
  • SSRIs — IBS-C especially
  • Antispasmodics (dicyclomine, hyoscyamine)
  • Peppermint oil
  • Pregabalin/gabapentin (off-label)

350.2.1.8 Diet

  • Low FODMAP — most evidence
  • Trigger food avoidance
  • Probiotics (specific strains)

350.2.1.9 Psychological

  • CBT — most evidence
  • Gut-directed hypnotherapy
  • Mindfulness

350.2.1.10 Functional Constipation Subtypes

  • Slow transit
  • Outlet dysfunction (pelvic floor dyssynergia)
  • Normal transit

350.2.1.11 Cannabinoid Hyperemesis Syndrome (CHS)

  • Heavy chronic cannabis
  • Cyclic vomiting
  • Relief from hot showers
  • Cessation curative

350.2.1.12 Cyclic Vomiting Syndrome

  • Migraine association
  • Amitriptyline, propranolol, topiramate

350.2.2 易混淆比范

Disorder Key Feature Treatment
IBS Rome IV pain + bowel Diet + medication by subtype
Functional dyspepsia Upper GI symptoms Per Ch348
Functional constipation Insufficient for IBS Laxatives, prucalopride
Functional diarrhea No pain Per cause
CVS Stereotyped episodes Amitriptyline preventive
CHS Cannabis + hot showers Cessation
Globus Lump sensation Reassurance, PPI

350.2.3 Special Topics

350.2.3.1 Bile Acid Diarrhea

  • Up to 30% of IBS-D
  • Diagnosed with SeHCAT or fecal bile acid
  • Cholestyramine, colesevelam

350.2.3.2 Microscopic Colitis

  • IBS-D mimic
  • Older patients
  • Diagnosis on colonoscopy biopsy
  • Treatment: budesonide

350.2.3.3 Post-Infectious IBS

  • Following gastroenteritis
  • Up to 20% develop IBS
  • More common after Campylobacter, Shigella, viral