Clinical spectrum of neurofibromatosis type 1 among children in a tertiary care center

Objectives:To identify the clinical and neuroradiological features of neurofibromatosis type 1 and the risk of malignancy in a pediatric age group.Methods:This observational retrospective cohort study was conducted at King Saud University Medical City, Riyadh, Kingdom of Saudi Arabia, for the patients with neurofibromatosis type 1 who were seen and had follow up from January 2000 to January 2019.Results:A total of 50 children were included. Approximately 90% of patients presented with café-au-lait macules, and 34% had skin-fold freckling. Moreover, 42% of the participants had a first-degree relative with neurofibromatosis type 1, and about a quarter presented with associated epilepsy. About 90% of the neuroradiological features were consistent with those of neurofibromatosis type 1. About 52% of the patients had one or multiple types of tumors, and 34% presented with optic pathway glioma.Conclusion:This study described clinical spectrum of neurofibromatosis type 1 among children. It showed also a higher percentage of tumors than previous studies.

Neurofibromatosis type 1 (NF1) is an autosomal dominant neurocutaneous disorder, that affects 1 in 3500 people worldwide.1 The NF1 is a complex disorder involving multiple body systems, such as the integumentary, visual, skeletal, and central nervous system (CNS); hence, it has different clinical manifestations. This condition is mainly characterized by cutaneous pigmented spots referred to as cafe-au-lait macules.2 The diagnosis of NF1 is mainly based on the criteria established by the National Institutes of Health (NIH) in 1988.3 Based on these criteria, patients are diagnosed with NF1 if they meet ≥2 of the following criteria: 6 or more cafe-au-lait macules with a diameter measuring >5 mm in prepubertal individuals and >15 mm in postpubertal individuals, 2 or more neurofibromas of any type or one plexiform neurofibroma, axillary or inguinal freckling (Crowe’s sign), optic pathway glioma (OPG), 2 or more Lisch nodules, dysplasia of the sphenoid wing or thinning of the long bone cortex (-/+ pseudarthrosis), and a first-degree relative with NF1 fulfilling the above mentioned criteria. The diagnostic criteria were revised in 1997 and were continuously used without modifications.4 Moreover, patients with NF1 have a higher risk of malignancies than individuals in the general population, with an estimated prevalence of 5%, and these malignancies are usually detected during childhood.1There are no available data on the radiologic features and the signs and symptoms at the time of clinical presentation, which are essential for the clinical knowledge of physicians in identifying patients with such condition. In addition, there is a lack of information about clinical outcomes, including the risk of malignancy, among patients with NF1. Therefore, the current study aimed to evaluate the different clinical manifestations and the radiological features of NF1 among pediatric patients. Moreover, the outcomes, which are essential for urgent interventions that can improve life expectancy, were assessed.