U.O. Nefrologia, Azienda Ospedaliero-Universitaria di Parma, Dipartimento di Medicina e Chirurgia, Università di Parma, Via Gramsci 14, 43126, Parma, Italy.
Casa di Cura Città di Parma, Unit of Diagnostic, Contrast enhanced and Interventional Ultrasound, Parma, Italy.
BMC Nephrol. 2020 Oct 12;21(1):430. doi: 10.1186/s12882-020-02084-1.
Medullary sponge kidney (MSK) is a rare disease characterized by cystic dilatation of papillary collecting ducts. Intravenous urography is still considered the gold standard for diagnosis. We identified a cohort of patients from our outpatient clinic with established diagnosis of MSK to outline some ultrasonographic characteristics that may help establish a diagnosis.
We conducted a retrospective study of patients seen between January 1st 2009 and January 1st 2019 in our clinic. Out of 4321 patients, 18 had a diagnosis of MSK. We reviewed their clinical and family history, laboratory data and imaging studies. Specifically, we focused on ultrasound imaging.
Patients were referred to our outpatient clinic because of renal impairment (44%), family history of nephropathy (17%), nephrolithiasis or an established diagnosis of MSK (39%). Seventy-two percent of patients presented with chronic kidney disease, 22% required hemodialysis. Urinary tract infections (44%), nephrolithiasis (33%), microscopic hematuria (50%) and proteinuria (44%) were reported. Seven patients underwent computed tomography; all of them received ultrasound. Ultrasound examination showed bilateral renal cysts, usually small and located in the renal medulla, and microcalcifications located in the medulla or within the cysts.
We identified a peculiar tetrad associated with MSK: 1) hypoechoic medullary areas, 2) hyperechoic spots, 3) microcystic dilatation of papillary zone, 4) multiple calcifications (linear, small stones or calcified intracystic sediment) in each papilla. The presence of this diagnostic tetrad, added to laboratory data and clinical history, could be helpful in the differential diagnosis to identify patients with MSK.
髓质海绵肾（MSK）是一种罕见的疾病，其特征为乳头集合管的囊性扩张。静脉尿路造影仍被认为是诊断的金标准。我们从我们的门诊中确定了一组经确诊的 MSK 患者，以概述一些可能有助于诊断的超声特征。
我们对 2009 年 1 月 1 日至 2019 年 1 月 1 日期间在我们的诊所就诊的患者进行了回顾性研究。在 4321 名患者中，有 18 名被诊断为 MSK。我们回顾了他们的临床和家族史、实验室数据和影像学研究。具体来说，我们专注于超声成像。
患者因肾功能不全（44%）、肾病家族史（17%）、肾结石或已确诊的 MSK（39%）而被转介到我们的门诊。72%的患者出现慢性肾脏病，22%需要血液透析。报告了尿路感染（44%）、肾结石（33%）、镜下血尿（50%）和蛋白尿（44%）。7 名患者接受了计算机断层扫描；他们都接受了超声检查。超声检查显示双侧肾脏囊肿，通常较小，位于肾脏髓质，并且微钙化位于髓质或囊肿内。
我们确定了与 MSK 相关的一个特殊四联症：1）低回声的髓质区域；2）高回声点；3）乳头区的微囊性扩张；4）每个乳头的多发性钙化（线性、小结石或钙化性囊内沉积物）。该诊断四联症的存在，加上实验室数据和临床病史，有助于在鉴别诊断中识别出 MSK 患者。
