Clinical Analysis And Gene Mutation Study Of A Case Of Sporadic Neurofibromatosis Type 1 Complicated With Alopecia Areata And Vitiligo

Objective: The clinical manifestations and pathogenic gene mutations of a patient with neurofibromatosis type 1(NF1),alopecia areata and vitiligo were studied in order to find new mutations so as to enrich the mutation spectrum of NF1 gene in Chinese population,observe the relationship between genotype and phenotype,especially the relationship between NF1 and autoimmune diseases,,and provide theoretical basis for clinical accurate treatment and genetic counseling of pedigrees.Methods: History collection,physical examination,laboratory examination and family gene mutation detection were performed in a patient with NF1 complicated with alopecia areata and vitiligo in the outpatient clinic of our department.The peripheral venous blood samples of the patients and their families were collected,and the exon regions of about 20 000 genes in the patient’s genome were sequenced by chip capture high-throughput sequencing,and the suspected pathogenic gene mutations were screened and verified by Sanger sequencing.Results:1.The patient was an 8-year-old male with coffee spots on the torso and limbs for 8 years,recurrent scalp alopecia for one and a half years,and scalp leukoplakia for 1 year.Clinical manifestations: coffee spots scattered in trunk and limbs,freckles pigmentation in axillary area,neck nodules with irregular alopecia and leukoplakia of the scalp.Attention deficit and hyperactivity disorder,childhood autism history of more than 1 year.2.Serum immunoglobulin Ig A decreased;abdominal ultrasound showed slightly thickened liver parenchyma echo;skull CT showed round low-density shadow in Cisterna Magna region and arachnoid cyst in Cisterna Magna.3.It was found that there was a missense mutation c.1885 G > An in exon 17 of NF1 gene,which was most likely to be the pathogenic mutation in this pedigree.The Sanger sequencing method was used to verify the patients in the family and healthy controls,and the results showed that the results were consistent with genotype and phenotypic co-segregation.Conclusions:1.According to the patient’s history,clinical manifestations and family genetic mutation detection,the diagnosis was type 1 neurofibromatosis,alopecia areata,vitiligo,attention deficit hyperactivity disorder and childhood autism.2.The pathogenic mutation in this pedigree in the missense mutation c.1885 G > A newly found in the NF1 gene.3.No relationship between NF1 genotype and phenotype was found in this study.