Department of Urology, Mayo Clinic, Rochester, Minnesota 55905, USA.
Urology. 2012 Feb;79(2):277-81. doi: 10.1016/j.urology.2011.07.1414. Epub 2011 Oct 19.
Medullary sponge kidney (MSK) is a disorder characterized by tubular dilation of renal collecting ducts and cystic dilation of medullary pyramids that has been associated with stone disease. The significance of nephrolithiasis and the mechanisms by which it occurs are incompletely understood. We describe clinical and metabolic features of nephrolithiasis in a cohort of patients with MSK.
Records were reviewed of 56 patients, all with radiographic diagnosis of medullary sponge kidney and data collected pertaining to presentation, stone events and recurrences, stone composition, and metabolic profile to perform a descriptive study with median 3.7 years follow-up.
Nephrolithiasis was confirmed radiographically in 39/56 patients (69.6%). No patient without evidence of nephrolithiasis developed a stone event, whereas 13/39 (33%) of those with nephrolithiasis developed a recurrent stone event. Stones were composed of calcium oxalate monohydrate, calcium oxalate dihydrate, calcium phosphate apatite, and uric acid. Metabolic profile was obtained for 26 of 39 (67%) stone-forming patients demonstrating abnormalities in 22/26 (84.6%). These included hypercalciuria, 58% (15/26); low urine volume, 35% (9/26); hyperuricosuria, 27% (7/26); hypocitraturia, 19% (5/26); elevated urine sodium, 15% (4/26); and hyperoxaluria, 12% (3/26).
Many patients with MSK have no evidence of nephrolithiasis. Among those who do, recurrence is common, and metabolic profile and composition are varied as in the general stone-forming population.
海绵肾（MSK）是一种以肾小管扩张和肾髓质锥体囊性扩张为特征的疾病，与结石病有关。肾结石的意义及其发生机制尚不完全清楚。我们描述了一组 MSK 患者肾结石的临床和代谢特征。
回顾了 56 例患者的病历，所有患者均经影像学诊断为海绵肾，并收集了与表现、结石事件和复发、结石成分和代谢特征相关的数据，以中位数为 3.7 年的随访进行描述性研究。
39/56 例（69.6%）患者经影像学证实有肾结石。无肾结石证据的患者均未发生结石事件，而 39 例肾结石患者中有 13 例（33%）发生了复发性结石事件。结石由一水合草酸钙、二水草酸钙、磷酸钙磷灰石和尿酸组成。对 39 例结石形成患者中的 26 例（67%）进行了代谢特征分析，结果显示 22/26（84.6%）存在异常。这些异常包括高钙尿症，占 58%（15/26）；低尿容量，占 35%（9/26）；高尿酸尿症，占 27%（7/26）；低柠檬酸尿症，占 19%（5/26）；尿钠升高，占 15%（4/26）；高草酸尿症，占 12%（3/26）。
许多 MSK 患者无肾结石证据。在有肾结石的患者中，复发很常见，代谢特征和成分与一般结石形成人群相似。
