UNASSIGNED: In a 6-year-old girl examined for abdominal pain, a cystic mass in the upper part of the right kidney was detected during an abdominal ultrasound. She was referred to pediatric oncology and urology for suspicion of a tumorous mass and the condition was assessed as a cystic nephroma. A heminephrectomy was then performed on the upper cystic part of the right kidney. The histological examination was inconclusive; therefore, genetic testing was recommended. Kidney and liver cysts were detected sonographically in the mother, but DNA analysis of the PKD1 and PKD2 genes did not reveal any pathogenic variant; the cause of the pathological formation in the kidneys remained unclear. Nine years later, next-generation sequencing of a panel of genes for kidney disease was performed and a heterozygous deletion was found on chromosome 16; this included exon 13 of the IFT140 gene. The same deletion was found in the patient\'s mother. Currently, the patient is 14 years old and has mild sonographic findings, normal glomerular filtration, mild proteinuria, and hypertension.
UNASSIGNED: Pathogenic variants of the IFT140 gene very rarely cause ADPKD; however, they should be considered in all children with autosomal dominant forms of PKD and asymmetric/atypical cystic kidney involvement or negative findings of PKD1 and PKD2.
■在一个6岁的女孩因腹痛进行检查时,在腹部超声检查中发现右肾上半部分的囊性肿块。她因怀疑肿瘤肿块而被转诊至儿科肿瘤科和泌尿科,并被评估为囊性肾瘤。然后在右肾的上囊性部分进行了肾切除术。组织学检查尚无定论;因此,建议进行基因检测。在母亲的超声检查中检测到肾脏和肝脏囊肿,但是PKD1和PKD2基因的DNA分析没有发现任何致病变异;肾脏病理形成的原因尚不清楚。九年后,对一组肾脏疾病基因进行了下一代测序,在16号染色体上发现了杂合缺失;这包括IFT140基因的外显子13.在患者的母亲身上也发现了同样的缺失。目前,患者14岁,有轻微的超声检查结果,正常肾小球滤过,轻度蛋白尿,和高血压。
■IFT140基因的致病变体很少引起ADPKD;然而,所有常染色体显性遗传形式的PKD和不对称/非典型囊性肾受累或PKD1和PKD2阴性的儿童都应考虑这些因素.