Department of Paediatric Surgery and Urology, Birmingham Children's Hospital, Steelhouse Lane, Birmingham, B4 6NH, United Kingdom.
J Pediatr Urol. 2019 Feb;15(1):46.e1-46.e6. doi: 10.1016/j.jpurol.2018.07.021. Epub 2018 Sep 6.
Renal agenesis and multicystic dysplastic kidney (MCDK) are usually associated with either an absent or atretic ureter. Occasionally, these renal anomalies may be associated with a dilated tortuous ureter, ureterocele or other cystic malformation of mesonephric duct (MND) remnants.
The objective of this study was to identify and classify anatomical variants of tubulocystic remnants of the MND, with a secondary focus on natural history and management outcomes.
A retrospective cohort study of patients seen in the study institution between 2007 and 2014 with a tubulocystic abnormality of MND structures associated with either MCDK or renal agenesis was conducted. Medical imaging and progress notes were reviewed for all patients. Data collected included anatomical information, surgical intervention, histology and outcomes of both conservatively managed and surgically resected MND remnant structures.
Nineteen patients were identified, 5 girls and 14 boys. Median age at presentation was 4.6 years. Anomalies of the MND occurred on the left in 9 patients and on the right in 10 patients. Mean follow-up was 3.4 years. Patients fell into 3 distinct anatomical groups: Type I, including orthotopic remnants corresponding to ureteric bud structures (ureter and trigone); Type II, including ectopic MND remnants of ureteric bud structures, and Type III, including complex remnants corresponding to MND structures other than those from ureteric bud (vas, epididymis and seminal vesicles). Anomalies of structures arising from urogenital sinus and paramesonephric ducts were also identified. Most patients were asymptomatic and successfully managed conservatively. Transvesical puncture of trigonal cysts provided effective decompression in 5 patients. Partial or complete MCDK regression was seen in 7 patients, whereas MND cystic anomalies did not regress spontaneously.
When MND tubulocystic structures persist along with renal agenesis or MCDK, most arise from ureteric bud structures in an orthotopic position as a ureterocele with or without a blind-ending ureter-like structure. Less commonly, ureteric bud structures insert ectopically into the urogenital tract, or tubulocystic structures arising from the remainder of the MND occur. Embryogenesis of other urogenital structures may also be abnormal, and conditions such as Zinner syndrome and obstructed hemivagina and ipsilateral renal agenesis syndrome should be considered.
Complications are uncommon, and surgical intervention should be limited to symptomatic patients. Remnants of metanephric blastema may involute, but MND remnants persist.
肾发育不全和多囊性发育不良肾（MCDK）通常与输尿管缺失或闭锁有关。偶尔，这些肾脏异常可能与扩张性迂曲的输尿管、输尿管囊肿或中肾管（MND）残余的其他囊性畸形有关。
本研究的目的是确定和分类 MND 的管状囊性残余物的解剖变异，并次要关注其自然病史和治疗结果。
对 2007 年至 2014 年间在研究机构就诊的患有与 MCDK 或肾发育不全相关的 MND 结构管状囊性异常的患者进行了回顾性队列研究。对所有患者的医学影像学和进展记录进行了回顾。收集的数据包括解剖信息、手术干预、组织学以及保守治疗和手术切除 MND 残余物结构的结果。
共确定了 19 名患者，其中 5 名女孩和 14 名男孩。中位就诊年龄为 4.6 岁。MND 异常发生在 9 名患者的左侧和 10 名患者的右侧。平均随访时间为 3.4 年。患者分为 3 个不同的解剖学组：I 型，包括与输尿管芽结构相对应的原位残余物（输尿管和三角区）；II 型，包括输尿管芽结构的异位 MND 残余物，III 型，包括与输尿管芽结构以外的 MND 结构相对应的复杂残余物（血管、附睾和精囊）。也发现了来自尿生殖窦和中肾旁管的结构异常。大多数患者无症状且保守治疗成功。经膀胱三角区囊肿穿刺术可有效减压 5 例。7 例患者出现部分或完全 MCDK 消退，而 MND 囊性异常则不会自发消退。
当 MND 管状囊性结构与肾发育不全或 MCDK 共存时，大多数起源于输尿管芽结构的正常位置，表现为输尿管囊肿，伴有或不伴有盲端输尿管样结构。较少见的是，输尿管芽结构异位插入尿生殖窦，或 MND 管状囊性结构起源于其余部分。其他泌尿生殖结构的胚胎发生也可能异常，应考虑 Zinner 综合征和梗阻性半阴道和同侧肾发育不全综合征等疾病。
并发症罕见，手术干预应仅限于有症状的患者。后肾胚基的残余物可能会消退，但 MND 残余物仍然存在。
