What is the workup for a patient presenting with abdominal bloating and fullness?

Workup for Abdominal Bloating and Fullness

Begin with a thorough clinical history and physical examination, then reserve invasive testing exclusively for patients with alarm features, recent symptom worsening, or abnormal physical findings. 1

Initial Clinical Assessment

Key History Elements to Obtain

• Assess for alarm features that mandate immediate investigation: unintentional weight loss, gastrointestinal bleeding, persistent vomiting, iron-deficiency anemia, or family history of gastrointestinal malignancy 1
• In women ≥50 years old, maintain high suspicion for ovarian cancer, as bloating and abdominal fullness are often presenting symptoms in this population 1, 2
• Evaluate temporal relationship to meals and associated symptoms (nausea, vomiting, constipation, diarrhea) to guide subsequent testing 3
• Document bowel movement patterns including frequency, consistency (using Bristol Stool Scale), and difficulty with evacuation 1
• Identify potential food triggers and relationship to specific dietary components (dairy, wheat, artificial sweeteners) 1

Physical Examination Focus

• Perform digital rectal examination to identify pelvic floor disorders, which frequently present with bloating and distention 2
• Assess for objective abdominal distention (measurable increase in girth) versus subjective bloating sensation alone 2
• Evaluate for signs of systemic disease including thyroid abnormalities, ascites, or organomegaly 1

Diagnostic Testing Algorithm

First-Line Laboratory Testing (Selective, Not Routine)

Order serologic testing for celiac disease with tissue transglutaminase IgA and total IgA levels in patients with bloating, particularly those with diarrhea or weight loss 1

• If serologies are positive, small bowel biopsy is mandatory to confirm diagnosis before initiating gluten-free diet 1

When to Order Imaging and Endoscopy

Reserve abdominal imaging and upper endoscopy exclusively for patients with:

• Alarm features (weight loss, bleeding, anemia) 1
• Recent worsening of symptoms 1
• Abnormal physical examination findings 1

The yield of imaging in the absence of these features is extremely low and should be avoided 1, 2

Consider upper endoscopy in patients >40 years with dyspeptic symptoms and bloating, especially in geographic regions with high Helicobacter pylori prevalence 1

Breath Testing Strategy

Use dietary restriction first (2-week trial) as the simplest and most cost-effective approach to diagnose food intolerances 1

Reserve breath testing for patients who fail dietary restriction trials:

• Hydrogen/methane breath testing for lactose, fructose, or sucrose intolerance 1
• Small intestinal bacterial overgrowth (SIBO) testing should be limited to high-risk patients: those with chronic watery diarrhea, malnutrition, weight loss, or systemic diseases causing small bowel dysmotility (cystic fibrosis, Parkinson disease) 1

Motility Testing (Highly Selective)

Do NOT order gastric emptying studies routinely for bloating and distention alone 1

Consider gastric emptying scintigraphy only when:

• Nausea and vomiting are prominent symptoms 1, 3
• Postprandial functional dyspepsia subtype is suspected 1

Whole gut motility and radiopaque transit studies should NOT be ordered unless treatment-refractory lower gastrointestinal symptoms exist warranting evaluation for neuromyopathic disorders 1

Anorectal Physiology Testing

In patients with bloating thought to be related to constipation or difficult evacuation, order anorectal physiology testing to rule out pelvic floor disorders 1, 2

• This is particularly important as dyssynergic defecation frequently causes constipation and bloating 1

Diagnostic Criteria Application

Use Rome IV criteria to diagnose primary abdominal bloating and distention 1, 2

The patient should NOT fulfill criteria for IBS, functional constipation, functional diarrhea, or functional dyspepsia to be diagnosed with isolated functional bloating 1

Common Pitfalls to Avoid

• Do not attribute all distention to gas accumulation: even small increases in intraluminal gas (approximately 10%) can trigger significant distention in susceptible patients 2
• Avoid over-testing in functional bloating: the yield is extremely low without alarm symptoms 3
• Do not miss ovarian cancer in women ≥50 years: maintain appropriate suspicion despite benign examination 1, 2, 3
• Do not routinely order probiotics: evidence does not support their efficacy for bloating and distention 1, 2

Special Considerations

If fecal elastase testing is indicated, consider chronic pancreatitis in patients with bloating accompanied by pain despite adequate pancreatic enzyme replacement 1

Plain abdominal radiograph may occasionally reveal increased stool burden, suggesting further evaluation for slow transit constipation or pelvic floor disorder in patients with functional constipation or IBS with constipation 1