KLHL40基因复合杂合变异导致先天性线状体肌病一例

Congenital nemaline myopathy caused by KLHL40 gene complex heterozygous variations:a case report

本文报道了1例KLHL40基因复合杂合突变导致线状体肌病的病例。患儿女,生后即起病,以"气促、肌力、肌张力低"为主要表现,常规治疗后症状加重,体格检查示四肢肌力低、肌张力低,原始反射均未引出;血清肌酸激酶升高。患儿未行肌肉活检。采用全外显子组二代测序证实患儿存在KLHL40基因复合杂合突变,包括c.932G>T(p.R311L)和c.1487T>A(p.M496K),并且分别来源于父母,其中c.932G>T(p.R311L)为已发现的突变位点,c.1487T>A(p.M496K)为新发现的突变位点。线状体肌病是一种罕见的先天性肌肉疾病,肌纤维中发现线状体是特征性肌肉病理改变。病理及基因诊断是诊断线状体肌病的金标准。

This article reported a case of nemaline myopathy caused by KLHL40 gene complex heterozygous mutations.This baby girl presented with shortness of breath,low myodynamia,and low muscle tension immediately after birth.However,her symptoms became worse after conventional treatment.Physical examination found lower muscle strength and muscle tone in four limbs and no primitive reflexes.The biochemistry test showed increased serum creatine kinase(CK).A muscle biopsy was not performed.The second-generation gene test confirmed the KLHL40 gene complex heterozygous mutations,which was a known mutation c.932G>T(p.R311L)and a de novo mutation c.1487T>A(p.M496K),inherited from the father and mother,respectively.Nemaline myopathy is a rare congenital muscular disease characterized by nemaline bodies in muscle fibers.Pathological and genetic diagnoses are the gold standards for the diagnosis of this disease.