Evaluation of Headache in a Child on Somatropin Therapy
A 9-year-old male who develops headache while on somatropin requires immediate evaluation for intracranial hypertension (benign intracranial hypertension/pseudotumor cerebri), which is a known adverse effect of growth hormone therapy that typically occurs within the first 8-12 weeks of treatment. 1
Immediate Clinical Assessment
Perform a fundoscopic examination to evaluate for papilledema, which is the hallmark sign of intracranial hypertension and can lead to permanent vision loss if untreated. 1 This examination should be done urgently, as the FDA label specifically warns about intracranial hypertension as a significant adverse reaction in children receiving somatropin. 1
Key Clinical Features to Assess
- Measure vital signs including blood pressure, as hypertension can contribute to headache and must be excluded. 2
- Conduct a complete neurologic examination to identify any focal neurologic deficits, altered mental status, or signs of increased intracranial pressure. 2
- Evaluate for specific symptoms of intracranial hypertension: visual changes (blurred vision, diplopia), nausea, vomiting, or tinnitus. 1
- Document headache characteristics: onset (sudden vs. gradual), severity, location, quality, timing, and any associated symptoms. 2
Neuroimaging Decision Algorithm
When MRI Brain is Indicated
If papilledema is present on fundoscopic examination, obtain MRI brain with and without IV contrast to exclude structural causes (tumor, hydrocephalus) and evaluate for signs of intracranial hypertension. 2 MRI is preferred over CT in non-emergency settings because it avoids radiation exposure and provides superior soft tissue detail. 2
When CT Head is Indicated
If the child presents with acute severe headache, altered mental status, or focal neurologic deficits, obtain non-contrast CT head emergently to exclude hemorrhage, mass effect, or hydrocephalus. 2 CT is faster and does not require sedation in most 9-year-olds, making it appropriate for emergency evaluation. 2
When Imaging May Not Be Immediately Necessary
If the headache is mild, the neurologic examination is completely normal, there is no papilledema, and vital signs are normal, you may observe closely with re-examination in 24-48 hours. 2 However, given the specific context of somatropin therapy and the known association with intracranial hypertension, a lower threshold for imaging should be maintained. 1
Management Based on Findings
If Intracranial Hypertension is Confirmed
- Discontinue somatropin immediately if intracranial hypertension is diagnosed. 1
- Refer to pediatric neurology and ophthalmology for co-management and monitoring of visual function. 1
- Consider lumbar puncture (after imaging excludes mass lesion) to measure opening pressure and confirm diagnosis. 2
If Imaging is Normal
- Re-evaluate the need for continued somatropin therapy versus temporary discontinuation while monitoring symptoms. 1
- Consider other causes of headache including migraine, tension-type headache, or viral illness, which are common in this age group. 2
- Ensure close follow-up with repeat fundoscopic examination if headaches persist or worsen. 2
Critical Pitfalls to Avoid
- Never restart somatropin without ophthalmologic clearance if intracranial hypertension was diagnosed, as recurrence can occur. 1
- Do not attribute headaches to "stress" or "primary headache" without first excluding intracranial hypertension in a child on growth hormone therapy. 1
- Avoid delaying fundoscopic examination, as papilledema can progress rapidly to permanent vision loss. 2, 1
- Do not perform lumbar puncture before neuroimaging if there are any signs of increased intracranial pressure or focal neurologic findings, as this risks herniation. 2