IMPE Abstracts

Background: Current safety of Recombinant human growth hormone (rhGH) treatment arises mainly from postmarketing surveillance. Headache is a relatively frequent symptom in children under rhGH. Secondary intracranial hypertension (SIH), is an adverse effect (AE), usually occurring within the first 12 weeks of treatment associated to headaches. Permanent visual defects are the most feared complication. Scarce information exists regarding incidence and natural history of visual impairment under rhGH.

Aim: To evaluate visual impairment and/or optic nerve affection in children throughout early rhGH treatment.

Materials and Methods: Prospective interventional study conducted from February 2018 to January 2020. Children ≥4 yr who received rhGH treatment for growth hormone deficiency (GHD), 0.16-0.25 mg/kg/w; Turner syndrome (TS), small for gestational age (SGA), 0.33 mg/kg/w and Prader Willy Syndrome (PWS) 1 mg/m2/d. Patients were assessed at basal, 1, 3, and 6 months of treatment. Each visit included clinical variables (adherence, auxology, AE, presence of headache), serum IGF1, IGFBP3, glucose, insulin, aldosterone, plasma renin activity, electrolytes and ophthalmologic evaluation [fundoscopy, optical coherence tomography (OCT), retinal nerve fiber layer (RNFL), ganglionic eye complex, ocular ultrasound, intraocular pressure (IOP), autorefractometry, biomicroscopy].

Results: Sixty patients were enrolled, 12 GHD, 11 ST, 31 SGA, 3 PWS, 3 TBI (23 females), with a median age of 8.08 yr (ranged 4.24-15). Median height was -2.25 ± 1.05 SDS. Baseline ophthalmologic evaluation was normal. Abnormal ophthalmological findings were observed in 15/60 (25%). Twelve patients showed changes in OCT, spontaneous recovery occurred in 8, whereas persistence or worsening of RNFL thickening lead to an MRI assessment and lumbar puncture (LP) in 4 patients (1 GHD, 2 SGA, 1 ST); only one referred headache. LP revealed opening pressure of 19, 21, 22 and 30 mmHg, respectively, the latter assumed as SIH at 1st month. Mean IGF1 1.12 ± 1.04 SDS, IGFBP3 -0.02 ± 2.34 SDS. ∆BMI -0.45 ± 0.71 SDS. Prevalence 1.6%. All patients received acetazolamide; median time for RNFL improvement took 4 months (range 4-8). One patient developed post-dural puncture headache. Three had elevated IOP. Along the protocol 19/60 referred headache (26 events). Abnormal ophthalmological findings were observed in 3/19 (2 mild changes in OCT; 1 elevated IOP).

Conclusion: We have demonstrated a marked prevalence of abnormal ophthalmological findings upon early rhGH treatment. These observations occurred in the absence of suggestive clinical symptoms, and conversely, headache did not predict SIB. The prevalence of SIH due to rhGH is higher than previously reported.