Solitary functioning kidney in children: clinical implications

ABSTRACT Introduction: Children with solitary functioning kidney (SFK) are prone to develop long term problems, which are not well represented in the literature. The extent to which the presence of associated congenital anomalies of kidney and urinary tract (CAKUT) further de-stabilize renal function is to be addressed. Objective: This study was conducted to evaluate the etiology, presentation, presence of CAKUT, and renal damage in children with SFK. Methods: All children with SFK who presented to the department of pediatric surgery from March 2014 to May 2016 were included in the study. Children with malignancy were excluded from the study. Results: Of the 20 patients with SFK, 14 (70%) had primary SFK (8 with agenesis and 6 with multicystic dysplastic kidney), 6 (30%) belonged to secondary SFK group, among them 3 had pelviureteric junction obstruction, 2 had posterior urethral valves and 1 had vesicoureteric reflux. Eight (40%) had associated CAKUT, 4 (20%) were asymptomatic while 8 (40%) had UTI and 6 (30%) had hypertension. Ten (50%) patients had reduced glomerular filtration rate (GFR) suggesting compromised renal function. Conclusion: Children with SFK have high morbidity especially when associated with ipsilateral CAKUT. Long-term periodical follow up is essential in these patients to improve clinical outcome.

摘要
引言：孤立肾（solitary functioning kidney, SFK）患儿易出现远期并发症，但现有文献对这类长期问题的记载尚不充分。目前尚未明确合并先天性肾及尿路畸形（congenital anomalies of kidney and urinary tract, CAKUT）会在多大程度上进一步损害肾功能，该问题有待进一步探讨。
目的：本研究旨在评估孤立肾患儿的病因、临床表现、合并CAKUT情况及肾损伤状况。
方法：纳入2014年3月至2016年5月于小儿外科就诊的所有孤立肾患儿作为研究对象，排除合并恶性肿瘤的患儿。
结果：本研究共纳入20例孤立肾患儿，其中14例（70%）为原发性孤立肾（8例为肾缺如，6例为多囊性发育不良肾）；6例（30%）为继发性孤立肾，其中3例合并肾盂输尿管连接部梗阻，2例合并后尿道瓣膜，1例合并膀胱输尿管反流。8例（40%）患儿合并CAKUT；4例（20%）无临床症状，8例（40%）出现尿路感染，6例（30%）合并高血压。10例（50%）患儿肾小球滤过率（glomerular filtration rate, GFR）降低，提示肾功能受损。
结论：孤立肾患儿的临床并发症发生率较高，尤其是合并同侧CAKUT的患儿。此类患者需接受长期定期随访，以改善临床预后。