Abstract：【Objective】To summarize the clinical manifestations of a case of Birk Barrel syndrome caused by KCNK9 gene mutation in our hospital, and to explore the characteristics and treatment of gene mutation of related diseases. 【Methods】The clinical datas of a case of Birk-Barel syndrome diagnosed and treated by the Department III of Neonatology in Hunan Children's Hospital in March 2019 were analyzed retrospectively. Using "KCNK9 gene", "KCNK9 imprinting syndrome" and "Birk-Barel syndrome" as key words to search databases at home and abroad, such as Wanfang database, CNKI and PubMed (from the establishment of database to May 2020), this paper summarizes the variation characteristics of KCNK9 gene and the clinical manifestations, treatment and prognosis of children with Birk-Barel syndrome. 【Results】This case is a boy. The main manifestations are: poor sucking, narrow and long craniofacial region, maxillary protrusion, mandibular retrusion, palmar penetration of both hands, contracture of index finger, middle finger and ring finger of both hands, inability to passively straighten, low muscle tension of limbs, incomplete original emission. High precision clinical exon sequencing showed that KCNK9 gene heterozygous mutation (NM-016601), the mutation site was c.706G > A (p.g236R). At present, there was no case report of Birk-Barel syndrome caused by KCNK9 gene mutation in China. A total of 20 cases of children with 3 articles abroad were retrieved, and 21 cases were added with this case. In 20 cases, the change of heterotopia was mainly c.770g > A, c.706g > C, c.706g > A, c.710c > A. In this case, the change of amino acid was p.a236n (1/21).【Conclusion】The main clinical manifestations of Birk-Barel syndrome are: congenital central hypotonia (manifested as hypokinesia, drowsiness, weak crying), severe eating difficulties caused by facial weakness and poor sucking, developmental retardation or mental retardation, and deformity. Treatment needs multidisciplinary intervention and regular follow-up and evaluation.
李军帅, 廖镇宇, 黄瑞文. KCNK9基因变异导致Birk-Barel综合征一例并文献复习[J]. 医学临床研究, 2020, 37(11): 1612-1615.
LI Jun-shuai, LIAO Zhen-yu, HUANG Rui-wen. Birk Barel Syndrome Caused by KCNK9 Gene Mutation: A Case Report and Literature Review. JOURNAL OF CLINICAL RESEARCH, 2020, 37(11): 1612-1615.
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2020, Vol. 37 
