CDn 40LGn 新发基因突变X连锁高IgM综合征1例n

• 作 者: 章学英 李玉川 陈辉 谢新宝
• 出 处: 中华实用儿科临床杂志
• 发表日期: 2021年13期
• 关键词: X连锁高IgM综合征 胆管扩张 CDn 40LGn 基因n

对2017年3月复旦大学附属儿科医院收治1例以胆管扩张为重要表现的n CDn 40LGn 新发基因突变X连锁高IgM综合征(XHIGM)患儿的临床资料进行回顾性分析。患儿为4岁男童，因反复腹泻0.5年、皮肤黄染5 d入院。胎儿期及出生史无异常；婴儿期曾患2次重症肺炎，左腋下淋巴结化脓性感染。体检发现体格发育明显落后，重度营养不良。皮肤、巩膜中度黄染，浅表淋巴结大，肝大。血白细胞、嗜酸性粒细胞升高、C反应蛋白明显升高；血红蛋白、白蛋白低下，高γ-谷氨酰转肽酶性胆汁淤积，免疫球蛋白IgG低下，IgM正常。影像学检查提示肝内外胆管弥散性扩张；肝脏病理发现胆小管增生，部分大胆管周围纤维组织增生；基因检测高通量测序发现XHIGM基因n CDn 40LGn 致病性突变(exon5 c．506A>G，p.Y169C)，母亲为携带者。入院后给予抗感染、调整饮食、白蛋白、静脉丙种球蛋白支持治疗，熊去氧胆酸利胆治疗，患儿病情好转出院。该病例提示XHIGM除常见的感染特点外，也可表现为弥散性肝内外胆管扩张、嗜酸性粒细胞明显升高。n CDn 40LGn 基因exon5 c．506A>G是该病的致病性突变。n “,”A retrospective analysis was performed on the clinical data of a child with X-linked hyper IgM syndrome (XHIGM) with cholangiectasis as a major manifestation in Children′s Hospital of Fudan University in March 2017.The patient was a 4-year-old boy who was admitted to the hospital due to repeated diarrhea for half a year and yellow skin for 5 days.No abnormalities were found in his fetal period and birth history; The patient had 2 severe pneumonias and suppurative infection of the left axillary lymph node in infancy.Physical examination revealed delayed physical development, severe malnutrition, moderately stained yellow, lymphadenopathy and hepatomegaly.Laboratory examinations showed elevated leukocyte, eosinophils and C-reactive protein, low hemoglobin and albumin, high gamma-glutamyl transpeptidase (GGT), low IgG and normal IgM.Imaging examination revealed diffuse expansion of intrahepatic and extrahepatic bile ducts.Hepatic pathology showed hyperplasia in the bile canaliculus and some fibrous tissues around the large bile ducts.High-throughput sequencing identified a pathogenic mutation in the XHIGM gene n CDn 40LGn (exon5 c. 506A>G, p.Y169C), with his mother as a carrier.After admission, the patient was given anti-infection, diet adjustment, albumin, intravenous immunoglobulin and ursodeoxycholic acid.The patient was discharged after the improvement in his condition.This case suggested that in addition to the common infection characteristics, XHIGM can also be manifested as diffuse intrahepatic, extrahepatic cholangiectasis and significantly elevated eosinophil.c.506A>G mutation inn CDn 40LGn was the pathogenic mutation of this disease.n