What is the recommended approach to diagnose Gastroesophageal Reflux Disease (GERD) in a patient, possibly with a history of obesity or smoking?

How to Diagnose GERD

For patients with typical reflux symptoms (heartburn and regurgitation) without alarm features, initiate an empiric trial of PPI therapy for 4-8 weeks and reserve objective testing for those who fail to respond adequately. 1

Initial Clinical Assessment

Symptom-Based Diagnosis

• Heartburn and acid regurgitation are the cardinal symptoms of GERD and are highly specific for the diagnosis. 2, 3
• Patients presenting with typical symptoms (heartburn, regurgitation) without alarm features can be diagnosed clinically and treated empirically. 1
• Alarm symptoms requiring immediate endoscopy include: dysphagia, bleeding, anemia, weight loss, and recurrent vomiting. 1

Risk Factor Assessment

• Evaluate for obesity, tobacco smoking, and genetic predisposition, which increase GERD risk. 3
• In patients with obesity or smoking history, these factors support the clinical diagnosis and emphasize the need for lifestyle modification. 1, 4

Diagnostic Algorithm Based on Symptom Type

For Typical Esophageal Symptoms (Heartburn/Regurgitation)

Step 1: Empiric PPI Trial

• Start with single-dose PPI therapy for 4-8 weeks. 1
• A positive response (≥75% reduction in symptom frequency) supports the diagnosis of GERD. 2
• If partial response, escalate to twice-daily PPI dosing for an additional 4-8 weeks. 1

Step 2: Objective Testing for Non-Responders

• Perform upper endoscopy (EGD) to assess for erosive esophagitis, Barrett's esophagus, hiatal hernia, and strictures. 1
• If endoscopy is negative or shows only mild findings, proceed to ambulatory reflux monitoring off PPI therapy. 1

For Extraesophageal Symptoms (Chronic Cough, Dysphonia, Globus)

Perform upfront objective reflux testing off medication rather than an empiric PPI trial. 1

• This approach is critical because 50-60% of patients with extraesophageal symptoms will not have GERD and will not respond to anti-reflux therapies. 1
• Empiric PPI trials have substantially lower diagnostic performance for extraesophageal symptoms (sensitivity 71-78%, specificity 41-54%). 1
• Cost-effectiveness studies favor early testing with reflux monitoring over empiric PPI trial in extraesophageal reflux. 1

Objective Testing Methods

Upper Endoscopy (EGD)

Indications for endoscopy include:

• Alarm symptoms (dysphagia, bleeding, anemia, weight loss, recurrent vomiting). 1
• Typical GERD symptoms persisting despite 4-8 weeks of twice-daily PPI therapy. 1
• Men older than 50 years with chronic GERD symptoms (>5 years) and additional risk factors (nocturnal reflux, hiatal hernia, elevated BMI, tobacco use) to screen for Barrett's esophagus and esophageal adenocarcinoma. 1
• Severe erosive esophagitis after 2 months of PPI therapy to assess healing and rule out Barrett's esophagus. 1

Key endoscopic findings:

• Grade erosive esophagitis according to Los Angeles classification (LA Grade B or higher supports GERD diagnosis). 1
• Assess for hiatal hernia (Hill grade of flap valve) and measure axial hernia length. 1
• Inspect for Barrett's esophagus using Prague classification and biopsy when present. 1

Ambulatory Reflux Monitoring

Wireless pH monitoring (96-hour) is the preferred method when available:

• Perform off PPI therapy to objectively assess acid exposure time (AET). 1
• Normal AET (<4.0%) on all 4 days has an odds ratio of 10.0 for predicting successful PPI withdrawal. 1
• Abnormal AET on ≥2 days has an odds ratio of 5.3 for predicting need for continuing PPI treatment. 1

24-hour pH-impedance monitoring is an alternative:

• Use off PPI therapy when wireless monitoring is unavailable and expertise in frame-by-frame interpretation exists. 1
• Preferred for evaluating extraesophageal symptoms as it detects weakly acidic, non-acidic, and proximal reflux episodes. 1
• Can be performed on twice-daily PPI in patients with previously proven GERD to determine mechanism of persistent symptoms. 1

Diagnostic Criteria Based on Testing Results

Confirmed GERD Diagnosis

Presence of any of the following:

• Los Angeles Grade B or higher esophagitis on endoscopy. 1
• AET >4.0% on at least 1 day of wireless pH monitoring, particularly if ≥2 days with AET >6%. 1
• Los Angeles Grade C or D esophagitis, bi-positional reflux, extreme acid exposure (AET >12% or DeMeester score >50), or large hiatal hernia represents severe GERD. 1

Borderline GERD

• Los Angeles Grade A esophagitis and/or elevated AET not meeting full GERD criteria. 1

No GERD (Functional Disorder)

• Normal endoscopy AND physiologic AET (<4.0%) on all days of wireless pH monitoring. 1
• These patients likely have functional esophageal disorder or reflux hypersensitivity and should be weaned off PPI. 1

Special Considerations

When to Perform Testing Off vs. On PPI

• Off PPI: For initial diagnosis in patients without typical symptoms, extraesophageal symptoms, or uncertain diagnosis. 1
• On PPI: Only in patients with established GERD diagnosis who have persistent symptoms despite high-dose acid suppression, to evaluate for ongoing acid or non-acid reflux. 1

Common Pitfalls to Avoid

• Do not rely solely on PPI response for diagnosis, as placebo effects occur and symptom response does not confirm GERD. 1
• Do not perform multiple empiric trials of different PPIs in extraesophageal symptoms—proceed to objective testing after one failed 12-week trial. 1
• Do not assume endoscopy alone rules out GERD, as 50-85% of GERD patients have non-erosive reflux disease requiring pH monitoring for diagnosis. 3, 5

Pre-Surgical Evaluation

• Objective documentation of pathologic GERD is mandatory before anti-reflux surgery. 1, 5
• Candidacy requires confirmatory evidence of pathologic GERD, exclusion of achalasia, and assessment of esophageal peristaltic function with high-resolution manometry. 1, 4