JC74 (Medicine) - Gastric motility problems, Benign esophageal lesions Flashcards
GERD
- Definition
- Pathophysiology
Definition: condition which develops when the reflux of stomach contents causes troublesome symptoms and/or complications
Pathophysiology:
- Imbalance between anti-reflux barriers and aggravating factors
- Anti-reflux barriers: e.g. LES, Hiatus, Oblique entrance of esophagus into stomach
- Aggravating factors: e.g. LES relaxation, Hiatus hernia, imported emptying…etc - Acid damage: mucosa expose to gastric content
- Chronic inflammation: complications e.g. esophagitis, strictures, Barret’s esophagus…etc
Physiological mechanisms against acid reflux?
Lower esophageal sphincter
Esophageal hiatus in crus of diaphragm
Oblique entrance of esophagus into stomach with Sharp angle on greater curvature (Angle of His)»_space; forms a flap/ valve
Aggravating factors of esophageal reflux
Transient LES relaxation after meal/ proximal gastric distension
Incompetent LES due to hiatus hernia or diet (fat, alcohol, chocolate, spicy food…)
Hypotensive LES after POEM surgery
Impaired esophageal emptying/ peristalsis or gastric dysmotility
Increase intra-abdominal pressure: obesity, large meal, pregnancy…
Excessive gastric acid production: e.g. H. pylori antral gastritis, Zollinger Ellison syndrome
Clinical manifestations of GERD
Heartburn sensation and acid regurgitation
- Post-prandial
- Supine or right decubitus position
- a/w water brash
Typical chest pain
Extra-esophageal symptoms: → Laryngo-pharyngeal reflux (LPR) with - Chronic cough - Hoarseness - Throat tightness → Asthma (correlated with GERD, reason unknown) → Recurrent chest infections → Dental erosion → Sleep disturbance
Complications of GERD
→ Odynophagia due to oesophagitis and ulcers
→ Dysphagia due to strictures
→ Barrett’s oesophagus
→ Adenocarcinoma
Factors that lower LES tone
→ Genetic determinants
→ Hiatus hernia
→ Diet/environment: alcohol, caffeine, smoking
→ Drugs (that cause sm relaxation), eg. NSAIDs, CCB, BB, nitrates, α-blocker, theophylline, anticholinergic
Ddx GERD
Achalasia
Zenker’s diverticulum
Gastroparesis
Angina pectoris
Causes of dyspepsia and esophagitis
Conditions most commonly associated with GERD
Pregnancy, Obesity
Long-term NG tube usage
Scleroderma (erosive GERD)
Multiple endocrine neoplasia (MEN)
Clinical classification of GERD
Montreal Classification
□ Non-erosive reflux disease (NERD) (60-80%):
→ Typical GERD symptoms but normal oesophageal mucosa with OGD
□ GERD with erosive oesophagitis (20-35%)
□ GERD with Barrett’s oesophagitis (1-5%)
Diagnostic tests for GERD (5)
Proton pump inhibitor test (first-line)
Diagnostic questionnaire: Frequency and severity of heartburn, acidity in stomach, acid regurgitation and use of antacids, >12 marks = GERD
24h Esophageal pH monitoring: Portable pH sensor and recorder/ Catheter-free pH system (BRAVO)/ Combined Multichannel Impedance and pH catheter
Upper endoscopy
Manometry: LES abnormalities
First diagnostic test for suspected GERD and NCCP (non-cardiac chest pain)
Proton pump inhibitor test
PPI empirical trail for 8 weeks
Symptoms improve = positive for GERD
ODG for GERD
- Indications
- Diagnostic of which conditions/ Role
Indications:
→ Diagnosis uncertain: atypical symptomatology or refractory to Tx
→ Alarming features suggestive of complications or malignancy
- Eg. dysphagia, odynophagia, GI bleeding, anaemia, weight loss, recurrent vomiting
→ Screening for complications if high-risk or clinically likely (eg. severe symptoms)
Role of OGD:
→ Diagnosis of erosive GERD
→ Detect complications, eg. strictures, Barrett’s oesophagus
→ Find underlying cause, eg antral gastritis, hiatus hernia
24h esophageal pH monitoring test
- Indication
- Test cut-off for Dx
Indication:
- Diagnosis of GERD refractory to treatment
Cut-off: total percentage time with pH <4.0 is over 4.2% is the distal esophagus; DeMeester score >14.72 (95th %ile) from frequency of reflux episodes and time required for
oesophagus to clear acid
24h esophageal pH test
- Modalities
- Advantages
- Disadvantages
Modalities:
- Antimony probe with portable pH recorder
- Catheter-free pH monitoring capsule with portable pH recorder
- Combined multichannel impedance and pH catheter
Advantages:
- Gold standard in GERD dx: High sensitivity for GERD
Disadvantages:
- Low sensitivity for NERD (non-erosive)
- Unpleasant procedure
- Not freely available
Comparative advantages between 2 modalities for esophageal pH monitoring
Capsule/ BRAVO system:
- Wireless, more convenient, less uncomfortable
- Placed during endoscopy > more specific and directed placement
- Offers 48h recording time
- Multiple capsules placed for more data
Multichannel intraluminal impedance (MII)
- Detects impedance between ring electrodes + pH monitoring»_space; detects acid and non-acid reflux
- Better dx of NERD
Endoscopy for GERD
- Normal endoscopic finding can Dx GERD, True or False
False
Endoscopy can Dx erosive GERD (30%), but cannot cover non-erosive GERD (70%)
Endoscopy can be normal in NERD even with abnormal esophageal pH
Clinical classification for esophagitis
LA classification of oesophagitis:
→ Grade A: ≥1 isolated mucosal breaks ≤5mm long not extending between tops of 2 mucosal folds
→ Grade B: ≥1 isolated mucosal breaks >5mm long not extending between tops of 2 mucosal folds
→ Grade C: ≥1 mucosal breaks bridging tops of folds but involving <75% of circumference
→ Grade D: ≥1 mucosal breaks briding tops of folds and involving >75% of circumference
Esophageal manometry
- Indications
- Function
Indication:
→ Symptoms suggestive of oesophageal motility disorder, eg. dysphagia, regurgitation
→ Prior to surgical therapy to r/o oesophageal motility disorder
Role: assess oesophageal motility to → R/o oesophageal motility disorder → Assess LES function: - Transient LES relaxation (TLESRs) - Hypotensive LES
Management options for GERD
- Lifestyle modifications
Lifestyle modification:
□ Stop smoking and drinking
□ Reduce weight
□ Elevate head of bed + avoid tight clothing
□ Diet changes:
→ Eat small meals, avoid late meals
→ Avoid reflux-promoting agents, eg. alcohol, coffee, chocolate etc (not evidence-based)
□ Drug changes: consider alternatives to reflux-promoting drugs, eg. theophylline, anticholinergics
Medical management options for GERD
Indication for each option
Acid-reducing agents: antacids, H2RA, PPI
- Antacids: symptoms management
- H2RA: add-on therapy for bedtime breakthrough GERD symptoms despite PPI; Tachyphylaxis
- PPI ***: symptom management, superior relief of heartburn/ regurgitation, healing esophagitis
(Prokinetics: metoclopramide, cisapride, sucralfate, baclofen have no role anymore)
PPI therapy for GERD
- Indications for maintenance therapy
- Risks of long-term use
Indication:
Long-term maintenance: Erosive esophagitis (LA grade C/D), Peptic stricture, Barrett’s esophagus
Intermittent maintenance: NERD patient with severe GERD symptoms, responsive to PPI
Risks:
Causative: Clostridium difficile infection***
Associative: Pneumonia, gastric cancer, OP, CKD, Stroke, Dementia…etc
Medical management options for GERD
- list examples of each class of drug
→ Antacids: Triact, magnesium / aluminum hydroxide
→ H2RA: cimetidine, raniditine, famotidine
→ PPI: omeprazole, lansoprazole, esomeprazole
Management of refractory GERD
Modifications to existing treatment? Investigations?
- Optimize PPI: dose, timing, compliance; switch class of PPI
- Add-on therapy:
- Nocturnal H2RA for night-time symptoms
- Alginate for post-dinner symptoms - Find cause:
- Early upper endoscopy if red-flag symptoms
- 24h pH monitoring and impedance study
- Esophageal manometry - Definitive surgery
First-line investigation and treatment for dyspepsia
Pt >60 years old or any alarming features of malignancy:
- Early endoscopy
Pt <60 years old without alarming features of malignancy:
- H.pylori test and treatment
- Empirical PPI +/- TCA or prokinetics
- Psychotherapy (last-line)
