What is the best course of action for an 8-year-old boy with nighttime vomiting (emesis) of mucous, poor appetite, and lower back pain for 4 weeks, with an X-ray showing bowel gas and no fever or upper respiratory symptoms?

Urgent Spine MRI Required for Suspected Spinal Neoplasm

This 8-year-old requires immediate MRI of the complete spine without and with IV contrast to evaluate for spinal neoplasm, which is the most likely diagnosis given the constellation of nighttime vomiting, 4-week history of lower back pain, and poor appetite. 1

Critical Red Flags Present

This child has multiple concerning features that mandate urgent advanced imaging:

• Night pain lasting >4 weeks is a cardinal red flag for spinal pathology in children 1
• Nighttime vomiting is a classic presentation of spinal neoplasm, occurring in 25-30% of children with these tumors 1
• Poor appetite combined with these symptoms suggests systemic illness from neoplasm 1
• The abdominal X-ray showing only bowel gas effectively rules out gastrointestinal obstruction, redirecting focus to the spine 2, 3

Why Spinal Neoplasm is Most Likely

Persistent nighttime back pain refractory to rest is the most common symptom of spinal neoplasm in children, present in 25-30% of cases. 1 The American College of Radiology specifically identifies this presentation pattern as highly concerning for:

• Intramedullary tumors (astrocytoma, ependymoma) - most common intraspinal tumors in children 1
• Benign bone tumors (osteoid osteoma, osteoblastoma, aneurysmal bone cyst) 1
• Malignant processes (leukemia, lymphoma) 1

The nighttime vomiting in this context likely represents increased intracranial pressure from a spinal cord tumor or referred symptoms from spinal pathology, not a primary gastrointestinal process. 1

Immediate Imaging Protocol

Order MRI complete spine without and with IV contrast as the initial study, bypassing plain radiographs. 1

The 2025 ACR Appropriateness Criteria explicitly state that when intraspinal neoplasm is suspected with clinical symptoms, MRI can be obtained forgoing conventional radiography to promptly identify pathology given its high sensitivity and specificity. 1 The contrast-enhanced study is essential because:

• It distinguishes inflammatory, infectious, and neoplastic processes 1
• It evaluates for epidural extension and soft tissue involvement 1
• It assesses for multifocal disease along the entire spine 1

Plain radiographs have low sensitivity for early spinal pathology and would only delay definitive diagnosis. 1

Why This is NOT Gastroenteritis or GERD

Several features argue strongly against common gastrointestinal diagnoses:

• Gastroenteritis presents with acute onset, typically includes diarrhea, and resolves within days - not 5 nights of isolated vomiting 4, 5, 6
• GERD causes postprandial vomiting throughout the day, not isolated nighttime episodes, and doesn't explain the back pain 1, 7
• The absence of fever, upper respiratory symptoms, and diarrhea makes viral illness unlikely 4, 5
• The mucousy vomit without bile or blood, combined with normal bowel gas pattern, rules out mechanical obstruction 2, 3

Critical Management Steps

1. Obtain MRI complete spine without and with IV contrast urgently (within 24-48 hours) 1
2. Consult pediatric neurosurgery or oncology immediately if imaging confirms neoplasm 1
3. Perform careful neurologic examination looking for motor weakness, gait disturbance, sensory changes, or bowel/bladder dysfunction - these indicate advanced disease 1
4. Assess for systemic symptoms including weight loss, fever, or night sweats that might suggest malignancy 1

Common Pitfall to Avoid

Do not attribute these symptoms to "just gastroenteritis" or GERD and delay spine imaging. 1 The American College of Radiology emphasizes that delay in imaging when spinal neoplasm is suspected can result in catastrophic consequences, including permanent neurologic deficit from spinal cord compression. 1 The combination of nighttime symptoms (both pain and vomiting) lasting weeks in a child is spinal neoplasm until proven otherwise.

The mucousy nighttime vomiting is likely a manifestation of increased intracranial pressure or autonomic dysfunction from spinal pathology, not a primary GI disorder. 1