What are the potential diagnoses for an 8-year-old male with intermittent vomiting, abdominal pain, and poor appetite for 4 days without fever, chills, or diarrhea?

Potential Diagnoses for an 8-Year-Old with Intermittent Vomiting and Abdominal Pain

The most critical diagnoses to exclude immediately are intussusception and appendicitis, as both can present with intermittent vomiting and abdominal pain in this age group and carry significant morbidity if missed. 1, 2

Immediate Life-Threatening Considerations

Intussusception

• Peak incidence is 5-9 months but can occur up to age 5 years, with 10-25% having an identifiable pathologic lead point in older children 1
• Classic presentation includes intermittent, colicky abdominal pain with sudden episodes where the child draws knees to chest, followed by calm periods between episodes 1
• Vomiting (often bilious as obstruction progresses) and lethargy are key features 1
• Ultrasound is the diagnostic test of choice with 98.1% sensitivity for the characteristic target lesion 1
• Plain radiographs can be normal even with intussusception present 2

Appendicitis

• Unlike adults, young children may display only lethargy or poor feeding rather than classic peritoneal signs 2
• Can present with persistent right lower quadrant tenderness, voluntary guarding, and poor oral intake 3
• Repeated physical examinations are essential as the clinical picture evolves 2
• Ultrasound can identify findings consistent with acute appendicitis 3

Malrotation with Intermittent Volvulus

• Bilious vomiting indicates intestinal obstruction requiring immediate surgical evaluation 4
• Abdominal radiographs can be normal even with early volvulus 2
• Upper GI series is the diagnostic test of choice if malrotation is suspected 5

Common Non-Emergent Diagnoses

Gastroenteritis

• Most common cause of vomiting in children, typically presents with diarrhea (absent in this case), though vomiting can precede diarrhea 6
• Usually viral etiology with rapid onset 6
• The absence of diarrhea after 4 days makes isolated gastroenteritis less likely 6

Gastroesophageal Reflux Disease (GERD)

• Can present with vomiting and abdominal pain in school-age children 5
• Milk protein allergy can mimic GERD and should be considered 5
• Upper endoscopy with biopsy is indicated if symptoms fail to respond to conservative management or if there is poor weight gain 5

Eosinophilic Esophagitis

• In children, presents with non-specific symptoms including abdominal pain and vomiting, particularly in younger age groups 5
• Children aged 6-10 years commonly present with abdominal pain (median age 9 years) 5
• Requires upper endoscopy with esophageal biopsies for diagnosis 5

Cyclic Vomiting Syndrome (CVS)

• Characterized by stereotypical episodes of acute-onset vomiting lasting less than 7 days, with at least 3 discrete episodes per year 5
• Abdominal pain is present in most patients during CVS episodes and should not preclude diagnosis 5
• Episodes often occur in early morning hours and may have prodromal symptoms lasting approximately 1 hour 5
• Triggers include stress (70-80% of patients), sleep deprivation, hormonal fluctuations, and infections 5

Cannabinoid Hyperemesis Syndrome (CHS)

• Less likely in an 8-year-old but should be considered in adolescents with episodic vomiting 7
• Requires cannabis use >1 year before symptom onset with frequency >4 times per week 7
• Compulsive hot-water bathing behavior reported in 71% of cases 7

Critical Diagnostic Approach

Red Flags Requiring Immediate Evaluation

• Bilious vomiting = intestinal obstruction until proven otherwise 4
• Blood in vomit or stool suggests GI bleeding, intussusception, or serious pathology 4
• Abdominal distension or significant tenderness points toward obstruction or appendicitis 4
• Poor weight gain or weight loss elevates concern from functional to organic disease 4
• Fever with toxic appearance suggests sepsis, meningitis, or appendicitis 4

Initial Workup

• Detailed history of fluid intake/output, character of vomit (bilious vs non-bilious), pattern of pain (constant vs intermittent), and associated symptoms 6
• Physical examination with particular attention to hydration status, abdominal tenderness location and quality, and repeated examinations over time 2
• Basic laboratory workup including CBC, electrolytes, glucose, liver function, lipase, and urinalysis 7

Imaging Strategy

• Ultrasound is first-line imaging for suspected intussusception or appendicitis in children 1, 3
• Plain abdominal radiographs have limited value but may show obstruction patterns or complications 1, 8
• Upper GI series if malrotation suspected or to exclude anatomic abnormalities 5
• Avoid routine gastric emptying scans as they have limited utility 7

Critical Pitfalls to Avoid

• Do not rely on normal abdominal radiographs to exclude intussusception or early volvulus 2
• Do not dismiss intermittent symptoms—serious pathology like intussusception can have pain-free intervals where children appear happy and playful 2
• Do not assume gastroenteritis without diarrhea after 4 days of symptoms 6
• Do not perform repeated endoscopies looking for a cause, as they may only show epiphenomena of recent vomiting (mild gastritis, Mallory-Weiss tear) 7
• Maintain high index of suspicion as young children may not localize pain well or describe symptoms clearly 2