Kusz Monika, Bieniaś Beata, Wieczorkiewicz-Płaza Anna, Brodzisz Agnieszka, Wieczorek Paweł, Sikora Przemysław
Department of Pediatric Nephrology.
Department of Pediatric Radiology, Medical University of Lublin, Lublin, Poland.
Medicine (Baltimore). 2019 Feb;98(7):e14529. doi: 10.1097/MD.0000000000014529.
Medullary sponge kidney (MSK) is a rare congenital abnormality characterized by cystic dilatation of the medullary collecting tubules. The disorder is likely to be complicated by nephrocalcinosis, urolithiasis, tubular dysfunctions, and urinary tract infections. In addition, it may be rarely associated with extrarenal anomalies.
We present a case of 17-year old girl who was referred for metabolic evaluation of bilateral nephrocalcinosis. Physical examination showed signs of mild, left-sided hemihypertrophy involving the lower limb, buttock, trunk, face, and tongue. The imaging studies of kidneys including intravenous urography and contrast computed tomography showed numerous medullary calcification and a typical picture of MSK-"paint brush"/"bouquet of flowers" appearance of the dilated tubules within the renal medulla. Laboratory evaluation revealed sterile pyuria, hypercalciuria, and hypocitraturia.
The patient was subsequently treated with potassium citrate, hydrochlorothiazide, low sodium and low oxalate diet accompanied by high fluid intake.
After a 1-year therapy the normalization of calciuria and citraturia occurred and no progression of nephrocalcinosis was observed.
We conclude that MSK should always be considered as a cause of nephrocalcinosis. Since the final diagnosis requires specific imaging techniques, the concomitant extrarenal abnormalities such as hemihypertrophy may facilitate diagnostic decisions.
髓质海绵肾（MSK）是一种罕见的先天性异常，其特征为髓质集合管的囊性扩张。该疾病可能并发肾钙质沉着症、尿路结石、肾小管功能障碍及尿路感染。此外，它可能很少与肾外异常相关。
我们报告一例17岁女孩，因双侧肾钙质沉着症接受代谢评估。体格检查显示有轻度左侧半身肥大的体征，累及下肢、臀部、躯干、面部和舌头。包括静脉肾盂造影和增强计算机断层扫描在内的肾脏影像学检查显示大量髓质钙化以及典型的MSK图像——肾髓质内扩张肾小管的“画笔”/“花束”外观。实验室评估显示无菌性脓尿、高钙尿症和低枸橼酸尿症。
该患者随后接受枸橼酸钾、氢氯噻嗪治疗，采用低钠和低草酸饮食并大量饮水。
经过1年治疗，尿钙和尿枸橼酸水平恢复正常，未观察到肾钙质沉着症进展。
我们得出结论，MSK应始终被视为肾钙质沉着症的一个病因。由于最终诊断需要特定的影像学技术，诸如半身肥大等并发的肾外异常可能有助于诊断决策。
