一般人群中髓质海绵肾(MSK)的确切患病率尚不清楚,多数患者无临床症状,而是由于其他原因行放射学检查而偶然发现的。一项研究估计MSK的患病率约为5/100 000。[14]Mayall GF. The incidence of medullary sponge kidney. Clin Radiol. 1970 Apr;21(2):171-4.http://www.ncbi.nlm.nih.gov/pubmed/5420265?tool=bestpractice.com 在施行静脉尿路造影术(intravenous uography, IVU)患者中,MSK患病率约为0.5%~1%。[15]Palubinskas AJ. Medullary sponge kidney. Radiology. 1961 Jun;76:911-9.http://www.ncbi.nlm.nih.gov/pubmed/13732350?tool=bestpractice.com 其他研究显示,MSK的患病率在有反复发作的钙肾结石患者中估计为3%~5%,在钙结石患者中为20%~25%。[16]Cameron JS. Medullary sponge kidney. In: Davison AM, Cameron JS, Grunfeld J-P, et al, eds. Oxford textbook of clinical nephrology, vol 3. 3rd ed. Oxford, UK: Oxford University Press; 2495-501.[17]Parks JH, Coe FL, Strauss AL. Calcium nephrolithiasis and medullary sponge kidney in women. N Engl J Med. 1982 May 6;306(18):1088-91.http://www.ncbi.nlm.nih.gov/pubmed/7070404?tool=bestpractice.com[18]Yendt ER, Jarzylo S, Finnis WA, et al. Medullary sponge kidney (tubular ectasia) in calcium urolithiasis. In: Smith LH, Robertson WG, Finlayson B, eds. Urolithiasis: clinical and basic research. New York, NY: Plenum; 1981:105-12.[19]Jungers P, Lacour E, Daudon M. Nephrolithiasis in patients with medullary sponge kidney. In: Borghi L, Meschi T, Briganti A, et al, eds. Proceedings of the 8th European Symposium on Urolithiasis. Parma, Italy: Editoriale Bios; 1999:589-91.
一些研究提示MSK多见于女性,然而其他研究则发现不存在性别差异。[17]Parks JH, Coe FL, Strauss AL. Calcium nephrolithiasis and medullary sponge kidney in women. N Engl J Med. 1982 May 6;306(18):1088-91.http://www.ncbi.nlm.nih.gov/pubmed/7070404?tool=bestpractice.com 由于MSK是进展性疾病,患者可能直到30岁以后才得以诊断。[2]Forster JA, Taylor J, Browning AJ, et al. A review of the natural progression of medullary sponge kidney and a novel grading system based on intravenous urography findings. Urol Int. 2007;78(3):264-9.http://www.ncbi.nlm.nih.gov/pubmed/17406139?tool=bestpractice.com 这种疾病多发生于30年龄段和50年龄段人群, 流行病学研究没有任何证据显示某特定人种、种族有高患病率。
患病率之间存在差异可能与放射学检查方法和研究人群特征不同有关,此外,计算机体层成像(CT)平扫已经代替 IVU 作为肾结石的诊断标准,这将可能导致 MSK 检出率降低。