Neurofibromatosis type 1 and infantile spasms

• Published in: Child's nervous system Vol. 25; no. 2; pp. 211 - 216
• Main Authors: Ruggieri, Martino, Iannetti, Paola, Clementi, Maurizio, Polizzi, Agata, Incorpora, Gemma, Spalice, Alberto, Pavone, Piero, Praticò, Andrea Domenico, Elia, Maurizio, Gabriele, Anna Lia, Tenconi, Romano, Pavone, Lorenzo
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Berlin/Heidelberg : Springer-Verlag 01-02-2009; Springer-Verlag
• Subjects: Adolescent; Child; Child, Preschool; Developmental disorders; Female; Genotype; Humans; Infant; Infantile spasms; Italy - epidemiology; Male; Medicine; Medicine & Public Health; Mutation; Neurofibromatosis; Neurofibromatosis 1 - complications; Neurofibromatosis 1 - epidemiology; Neurofibromatosis 1 - genetics; Neurofibromin 1 - genetics; Neurosciences; Neurosurgery; Original Paper; Phenotype; Prevalence; Prospective Studies; Retrospective Studies; Spasms, Infantile - epidemiology; Spasms, Infantile - etiology; Italy; Developmental disorders; Infantile spasms; Neurofibromatosis
• ISSN: 0256-7040; 1433-0350
• DOI: 10.1007/s00381-008-0706-5

Background There is no agreement on the prevalence, natural history and outcome of infantile spasms (IS) in neurofibromatosis type 1 (NF1). By contrast, its prevalence and outcome are well characterised in the setting of other neurocutaneous disorders (e.g. tuberous sclerosis). Materials and methods The aim of the present study was to try to establish a genotype-phenotype correlation in IS in the setting of NF1. A retrospective (years 1990-2000) and prospective (years 2000-2006) study in three paediatric centres in Italy were taken as referral populations for: (1) children with NF1 and (2) neurological problems in childhood. Results Ten NF1 patients have had IS. The calculated population-based: (1) prevalence of IS in NF1 (0.76%) was higher than the reported frequency of IS in the general population (0.02-0.05%) and (2) frequency of NF1 in the IS series in two out of three centres (0.62-0.90%) was lower than the estimated frequencies in the literature (1.5-3.0%). Patients had psychomotor delay preceding the spasms (50%), symmetrical spasms (50%), typical (80%) and modified (20%) hypsarrhythmia and foci of spikes and waves and a good response to corticosteroid treatment (50%). Outcome was good in 30%. Imaging revealed high-signal foci in atypical locations (sub-cortical and central brain regions). Deoxyribonucleic acid analysis revealed three novel NF1 gene mutations without genotype-phenotype correlation. Conclusion Even though the combination of IS and NF1 does not seem to be coincidental, it is certainly an unusual event in NF1--rarer than in other neurocutaneous disorders. Spasms in NF1 are not associated with specific genetic defects.