348.1 🎓 醫孞生版

348.1.0.1 📌 䞀頁重點

348.1.0.1.1 Gastroesophageal Reflux Disease (GERD)
348.1.0.1.1.1 Definition
  • Symptoms or complications from reflux of gastric contents into esophagus
  • ~ 20% adults have weekly symptoms in US/Europe
348.1.0.1.1.2 Pathophysiology
  • Transient LES relaxations (TLESRs) — main mechanism
  • LES tone reduced
  • Hiatal hernia
  • Delayed gastric emptying
  • Increased intra-abdominal pressure (obesity, pregnancy)
  • Esophageal motility dysfunction
348.1.0.1.1.3 Symptoms

Typical: - Heartburn (retrosternal burning) - Regurgitation (acid taste)

Atypical: - Chronic cough - Wheezing / asthma - Hoarseness - Throat clearing - Globus sensation - Dental erosions - Chest pain (mimics cardiac)

348.1.0.1.1.4 Complications

Esophagitis (LA Grade A-D): - A: ≀ 5 mm - B: > 5 mm - C: < 75% circumferential - D: > 75% circumferential

Strictures (peptic, distal esophagus)

Barrett’s Esophagus: - Specialized intestinal metaplasia (replacement of squamous with columnar) - Risk factor for adenocarcinoma - Risk: 0.1-0.5% per year low-grade dysplasia; higher for high-grade

Adenocarcinoma: - Increasing incidence - Distal esophagus

348.1.0.1.1.5 Diagnosis

Clinical: - Typical symptoms + response to PPI = sufficient

EGD: - Alarm features (≥ 50-60 yo, weight loss, dysphagia, bleeding, vomiting) - Refractory symptoms - Barrett’s surveillance

24-Hour Ambulatory pH Monitoring: - Gold standard for diagnosis of acid exposure - Capsule (Bravo) or catheter-based - For PPI-refractory or atypical symptoms - Off PPI for testing

Esophageal Manometry: - For motility disorders - Required pre-fundoplication

348.1.0.1.1.6 Treatment

Lifestyle: - Weight loss - Elevate head of bed - Avoid triggers (fatty foods, citrus, chocolate, mint, caffeine, alcohol) - Avoid late meals (≥ 3 hr before bedtime) - Smoking cessation

Pharmacologic:

PPI (Proton Pump Inhibitor) — First-Line: - Omeprazole, esomeprazole, pantoprazole, lansoprazole, dexlansoprazole, rabeprazole - Take 30-60 min before meals - Once daily standard; BID for severe - Long-term concerns: B12 deficiency, hypomagnesemia, pneumonia, C. diff, CKD (controversial), osteoporosis (controversial)

H2 Receptor Antagonists: - Famotidine (preferred), ranitidine (recalled), nizatidine, cimetidine - Useful for nighttime breakthrough - Less potent than PPI - Tachyphylaxis with chronic use

Antacids: - Calcium carbonate, magnesium hydroxide - Quick relief - Short duration

Vonoprazan (Potassium-Competitive Acid Blocker, PCAB): - Newer (2022 FDA for H. pylori, 2024 for erosive esophagitis) - Faster onset + more sustained acid suppression - Better for severe esophagitis

Prokinetics: - Metoclopramide (limited use due to tardive dyskinesia) - Erythromycin (motilin agonist) - Limited evidence

Step-Up vs Step-Down: - Step-up: H2 → PPI as needed - Step-down: PPI initially, reduce over time

Surgery: - Fundoplication (Nissen 360°) for refractory or PPI-intolerant - LINX device (magnetic ring) - TIF (transoral incisionless fundoplication) endoscopic - For severe with hiatal hernia - Pre-op manometry essential

Endoscopic Therapy: - RFA (radiofrequency ablation) for Barrett’s - EMR (endoscopic mucosal resection) for nodular Barrett’s or early cancer - ESD (endoscopic submucosal dissection) for select

348.1.0.1.1.7 Barrett’s Esophagus

Definition: - Salmon-colored mucosa on EGD - Intestinal metaplasia (goblet cells) on biopsy

Risk Factors: - GERD long-standing - Obesity - Male - White - Smoking - ↑ Age

Surveillance: - EGD with biopsies - 4-quadrant biopsies every 1-2 cm - Interval based on dysplasia: - No dysplasia: every 3-5 years - Low-grade dysplasia: every 6 mo or RFA - High-grade dysplasia: RFA + EMR

Treatment: - PPI lifetime - RFA for dysplasia - EMR for nodular Barrett’s or early cancer - ESD select cases - Esophagectomy for invasive cancer

348.1.0.1.2 Eosinophilic Esophagitis (EoE)
348.1.0.1.2.1 Definition
  • Chronic immune-mediated esophageal inflammation
  • ≥ 15 eosinophils/HPF on biopsy
  • Symptoms of esophageal dysfunction
348.1.0.1.2.2 Epidemiology
  • Increasing (atopic populations)
  • Young to middle-aged adults
  • Male predominance
  • Family clustering
  • Atopic comorbidities (allergic rhinitis, asthma, atopic dermatitis, food allergies)
348.1.0.1.2.3 Symptoms
  • Dysphagia (#1 in adults)
  • Food impaction (recurrent)
  • Chest pain
  • Heartburn
  • Failure to thrive (pediatric)
348.1.0.1.2.4 Diagnosis
  • EGD: linear furrows, concentric rings (“trachealization”), white exudates, strictures
  • Biopsy: 4-6 samples from multiple levels, ≥ 15 eos/HPF
  • Excluded: PPI-responsive, GERD with high eos
  • Allergy testing optional
348.1.0.1.2.5 Treatment
  • PPI (first-line; 30-40% respond)
  • Swallowed topical corticosteroids (STC): fluticasone, budesonide
  • Diet: 6-food elimination diet (dairy, wheat, egg, soy, nuts, seafood)
  • Dupilumab (anti-IL-4Rα) — LIBERTY-EoE-TREET (2022) + FDA 2022
  • Endoscopic dilation for strictures
  • Tezepelumab (anti-TSLP) — emerging
  • Cendakimab (anti-IL-13) — Phase 3
348.1.0.1.3 Achalasia
348.1.0.1.3.1 Definition
  • LES failure to relax + absent peristalsis
  • “Bird beak” appearance on esophagram
  • Progressive dysphagia + weight loss
348.1.0.1.3.2 Diagnosis
  • Manometry (gold standard):
    • Chicago Classification (Types I-III)
    • Type I: classic (no contractility)
    • Type II: with compression (panesophageal pressurization)
    • Type III: spastic
  • Esophagram: bird beak
  • EGD: rule out pseudoachalasia (cancer)
348.1.0.1.3.3 Treatment
  • Pneumatic dilation (endoscopic)
  • Peroral endoscopic myotomy (POEM) — newer
  • Heller myotomy (surgical) — traditional
  • Botox injection (temporary; elderly)
  • Medical: nitrates, CCBs (limited)
  • Type III achalasia: POEM preferred
348.1.0.1.4 Diffuse Esophageal Spasm (DES)
348.1.0.1.4.1 Clinical
  • Chest pain mimicking cardiac
  • Dysphagia
  • Triggered by stress, hot/cold
348.1.0.1.4.2 Diagnosis
  • Manometry: > 20% premature contractions
  • “Corkscrew esophagus” on barium
348.1.0.1.4.3 Treatment
  • CCBs, nitrates
  • POEM for refractory
348.1.0.1.5 Scleroderma Esophagus
348.1.0.1.5.1 Clinical
  • Heartburn + dysphagia
  • LES dysfunction + absent peristalsis
  • Reflux + Barrett’s risk
348.1.0.1.5.2 Treatment
  • High-dose PPI
  • Promotility (limited)
348.1.0.1.6 Esophageal Cancer
348.1.0.1.6.1 Subtypes

Adenocarcinoma: - Increasing in US/Europe - Distal esophagus - Barrett’s metaplasia precursor - Risk factors: GERD, obesity, smoking, male, white, Helicobacter (negative — protective against adeno)

Squamous Cell Carcinoma: - Decreasing - Mid-upper esophagus - Risk factors: smoking + alcohol (synergistic), HPV, hot beverages, achalasia, lye injury, tylosis, Plummer-Vinson

348.1.0.1.6.2 Staging
  • TNM
  • EUS for T and N
  • PET-CT for distant mets
348.1.0.1.6.3 Treatment
  • Early (T1aN0): EMR or ESD
  • Locally advanced: neoadjuvant chemoradiation → esophagectomy
  • Metastatic: chemotherapy + immunotherapy
    • Pembrolizumab + chemo (KEYNOTE-590) — first-line for esophageal squamous and adenocarcinoma
    • Nivolumab + ipilimumab + chemo (CheckMate 648)
    • Adjuvant nivolumab (CheckMate 577) post-chemoradiation/surgery if residual disease
348.1.0.1.6.4 Adjunctive
  • Stent for palliation (dysphagia)
  • PEG tube for nutrition
  • Pain management
  • Palliative care

348.1.0.2 🩺 床邊速查

  • GERD: heartburn + regurgitation; PPI foundation; lifestyle + endoscopy if alarm features
  • Barrett’s: salmon mucosa + intestinal metaplasia; surveillance + RFA for dysplasia
  • EoE: dysphagia + food impaction; ≥ 15 eos/HPF; PPI/STC + dupilumab (LIBERTY-EoE 2022)
  • Achalasia: bird beak + dysphagia; manometry; POEM or Heller myotomy or dilation
  • Esophageal SCC: smoking + alcohol synergy
  • Esophageal adenocarcinoma: GERD + Barrett’s; KEYNOTE-590 pembrolizumab + chemo
  • Vonoprazan: PCAB newer (FDA 2022 H. pylori, 2024 erosive esophagitis)