Evaluation of Clinical Findings and NF1 Genetic Variants in Patients Diagnosed with Neurofibromatosis Type 1: A Single-Center Experience

Objective: Neurofibromatosis type 1 (NF1) is a common neurocutaneous syndrome with multisystemic involvement that facilitates tumour formation. The aim of this study was to evaluate the demographic and clinical characteristics as well as genetic results of pediatric patients diagnosed with neurofibromatosis type 1. Materials and Methods: This retrospective, cross-sectional descriptive study included 23 patients. Main disease criteria, clinical features, and genetic results obtained using next-generation sequencing and multiple-ligation probe amplification techniques were recorded. Information on zygosity, mutation types, variant positions, ACMG classification and inheritance models were analysed. Results: Café-au-lait spots were present in all patients. Inguinal/axillary freckling was the second most common finding seen in 60.9% of patients. Lisch nodules were observed in patients older than six years, whereas choroidal abnormalities were common in younger patients. Optic glioma was found in 13% of patients and cutaneous neurofibromas in 21.7% of patients, which is lower than that observed in adult patients. Focal signal intensity image was more common in patients with cognitive impairment (OR: 4.50, CI 95% 0.659-30.715, p=0.02). Epilepsy was diagnosed in two patients and treated with a single drug. Macrocephaly (30.4%) was the most common cranial deformity. Missense mutations (43.5%) were the most common, while one frameshift novel mutation (c.6771del. K2257Nfs*8) was identified. Conclusion: The emergence of new genetic technologies and advances in health care may facilitate earlier diagnosis of neurofibromatosis and the prediction and treatment of complications that may develop.