What is the diagnostic approach for Gastroesophageal Reflux Disease (GERD)?

How to Diagnose GERD

For patients with typical GERD symptoms (heartburn and regurgitation) without alarm features, begin with an empiric 4-8 week trial of once-daily PPI therapy before meals—this serves as both diagnostic test and initial treatment. 1, 2

Initial Clinical Assessment

Identify typical vs. atypical presentations:

• Typical symptoms with highest specificity for GERD are heartburn and acid regurgitation 1, 3
• Atypical symptoms include dysphagia, chest pain, chronic cough, laryngitis, asthma, and dental erosions 1
• Alarm features requiring immediate endoscopy: weight loss, dysphagia, or epigastric mass on examination 4

Diagnostic Algorithm Based on Presentation

For Typical GERD Symptoms (Heartburn/Regurgitation)

Step 1: Empiric PPI Trial

• Start once-daily PPI before meals for 4-8 weeks 1, 2
• If inadequate response, increase to twice-daily dosing 1
• Taper to lowest effective dose if symptoms resolve 1

Step 2: If PPI Trial Fails

• Proceed directly to upper endoscopy to evaluate for erosive esophagitis, Barrett's esophagus, strictures, or alternative diagnoses 4, 1
• Obtain at least 5 esophageal mucosal biopsies if dysphagia is present to rule out eosinophilic esophagitis 4

Step 3: If Endoscopy is Normal

• Perform esophageal manometry to rule out achalasia, distal esophageal spasm, or other motility disorders that mimic GERD 4, 1
• Ensure some peristaltic function is preserved (important if considering anti-reflux surgery) 4

Step 4: Ambulatory Reflux Monitoring

• Perform off PPI therapy using catheter-based pH monitoring, wireless pH capsule, or combined impedance-pH monitoring 4, 1
• This determines if excessive esophageal acid exposure exists when acid suppression is withheld 4
• For patients with previously confirmed GERD and refractory symptoms, pH-impedance monitoring on PPI therapy can distinguish PPI-refractory GERD from PPI-controlled GERD 5

For Atypical or Extraesophageal Symptoms (Without Typical GERD Symptoms)

Do NOT start with empiric PPI trial—proceed directly to objective testing. 4, 1

The rationale: PPI trials have sensitivity of only 71-78% and specificity of 41-54% even for typical reflux symptoms, and performance is substantially lower for extraesophageal manifestations 4. Additionally, symptom improvement on PPI may result from mechanisms other than acid suppression and should not confirm GERD diagnosis 4, 1.

Diagnostic approach:

• Perform upper endoscopy first 1
• Follow with esophageal manometry 1
• Complete with ambulatory reflux monitoring off PPI therapy 4, 1
• No single test conclusively identifies GERD as the cause of extraesophageal symptoms—diagnosis requires global clinical impression from symptoms, treatment response, endoscopy, and reflux testing combined 4, 1

Specific Diagnostic Tests

Upper Endoscopy

• Assess for erosive esophagitis, Barrett's esophagus with biopsy when present, peptic stricture, hiatal hernia, and alternative diagnoses 1, 2
• Indicated for alarm symptoms or failed empiric PPI therapy 1, 2

Esophageal Manometry

• Localizes the lower esophageal sphincter for pH probe placement 1
• Evaluates peristaltic function and contractile reserve 1, 5
• Rules out achalasia, distal esophageal spasm, and other motility disorders 4, 1

Ambulatory Reflux Monitoring Options

• Catheter-based pH monitoring: quantifies distal esophageal acid exposure 6
• Wireless pH capsule: allows 48-96 hour monitoring 1
• Combined impedance-pH monitoring: detects both acid and non-acid reflux events, distinguishes hypersensitivity syndromes from functional syndromes 4, 6

Critical Pitfalls to Avoid

• Never rely solely on PPI response to confirm GERD diagnosis, as improvement may occur through placebo effects or non-acid suppression mechanisms 4, 1
• Do not continue long-term PPI therapy without objective confirmation of GERD 1, 2
• Do not assume all extraesophageal symptoms are GERD-related without proper testing—consider large differential of alternative diagnoses 4, 1
• Do not perform reflux monitoring on PPI therapy for initial diagnosis—unclear relevance of normative data makes interpretation difficult 4
• Do not skip esophageal biopsies when evaluating dysphagia—obtain at least 5 specimens to exclude eosinophilic esophagitis 4