Diagnostic Approach for Child with Recurrent Epigastric Pain Relieved by Food
Direct Answer
H. pylori stool antigen test is the most appropriate initial diagnostic test for this child. 1, 2 The clinical presentation of recurrent epigastric pain that improves with eating is highly suggestive of peptic ulcer disease, and non-invasive H. pylori testing should be offered in patients without alarm features who have had symptoms for 4 weeks or longer. 2
Clinical Reasoning
Why Stool Antigen Test First
The American Academy of Pediatrics recommends beginning with conservative dietary modifications for 2-4 weeks before any invasive testing in pediatric patients with epigastric symptoms. 2 However, when symptoms persist beyond 4 weeks, non-invasive H. pylori testing becomes the next appropriate step. 2
H. pylori stool antigen testing demonstrates excellent diagnostic accuracy in children with recurrent abdominal pain: sensitivity of 85-98%, specificity of 93-100%, positive predictive value of 89.7-100%, and negative predictive value of 90-96.5%. 3, 4, 5, 6
The test is relatively simple, inexpensive, time-saving, and avoids the risks and inconvenience of endoscopy. 3, 7
When to Proceed to Upper Endoscopy
Upper endoscopy should be reserved for specific situations, not as the initial test:
Presence of alarm features: occult blood in stool (indicating GI bleeding), vomiting, fever, tachycardia, weight loss, or signs suggesting perforation. 1, 2
Failure to respond to empiric PPI therapy after 2 weeks. 2 If symptoms persist despite treatment, endoscopy becomes necessary to visualize ulcers directly, obtain tissue for histopathology, and rule out other serious conditions including eosinophilic esophagitis, Crohn's disease, and malignancy. 1
The American Gastroenterological Association recommends upper endoscopy with biopsy as the confirmatory diagnostic test only when alarm features are present, as it is the only test that simultaneously visualizes ulcers, obtains tissue for histopathology, and performs multiple H. pylori tests from biopsies. 1
Critical Pitfalls to Avoid
Never dismiss cardiac causes regardless of age—myocardial infarction can present as isolated epigastric pain in adolescents with 10-20% mortality if missed. 2 Obtain an ECG within 10 minutes if there is any concern. 2
Check for peritoneal signs suggesting perforated peptic ulcer, which carries 30% mortality if treatment is delayed. 1, 2
Do not proceed directly to endoscopy without considering non-invasive testing first, as endoscopy requires sedation with associated risks and is expensive and inconvenient in children. 3, 7
Assess for tachycardia ≥110 bpm, fever ≥38°C, or hypotension, which predict perforation or sepsis requiring immediate intervention. 2
Management Algorithm After Testing
If H. pylori stool antigen is positive: Provide eradication therapy. 2
If H. pylori stool antigen is negative but symptoms persist: Initiate full-dose PPI therapy with omeprazole 20 mg once daily before meals for 2 weeks. 2 If symptoms improve, continue for 8-12 weeks total. 2
If PPI therapy is ineffective: Reassess the diagnosis and proceed to upper endoscopy, as conditions like eosinophilic esophagitis, gastroparesis, and Crohn's disease will not respond to acid suppression. 2