Nephrolithiasis and Rare Nephrocalcinosis Study Group, Italian Society of Nephrology, 00185 Rome, Italy.
Department of Biostatistics, Consortium for Biological and Pharmacological Evaluations (CVBF), 27100 Pavia, Italy.
Nutrients. 2024 Sep 4;16(17):2984. doi: 10.3390/nu16172984.
Dietary factors may be implicated in the formation of kidney stones and should be closely monitored. To achieve this aim, patients are routinely assessed by means of generic dietary recall, a tool widely used by authors in a range of extensive patient populations to record food intake; the findings obtained, however, may be skewed due to dietary variations and underestimation of the effect of food additives. Fifty Frequent Kidney Stone Formers (FKSFs, mean age: 54.3 ± 13.9 years) with normal kidney function, absence of comorbidities, and reliable compliance were selected from a total of 68 patients' resident in Sardinia, an Italian island where genetic admixtures have been relatively rare for generations. The study, conducted from 1 January 2020 to 31 December 2023, was aimed at assessing nutritional values based on the meticulous recording of food quantities, quality, and potential modifications related to food preparation. Patients were selected during an initial clinical check-up and all efforts made to ensure they were capable of reliably recording all food and drinks consumed. A seven-day food diary was provided in which food and drink intake and their impact on 24 h urine output was recorded. The following parameters were measured in both foods and urine output: citrates, oxalates, calcium, phosphorous, uric acid, proteins and nitrogen compounds, magnesium, sulfates, potassium, carbohydrates, free fatty acids. Study outcomes established the presence of hypocitraturia, hyperoxaluria, hypercalciuria, and moderately high levels of nitrogen compounds. Univariate analysis followed by multivariate analysis for further confirmation were performed and the following observations made. Citrate intake correlated with citraturia but did not promote oxaluria; calcium intake promoted onset of sulfaturia, azoturia, and ammoniuria, whilst magnesium correlated with magnesiuria but not with oxaluria, calciuria, phosphaturia, and azoturia; sulfate intake elicited onset of azoturia but not kaliuresis; potassium intake promoted oxaluria and protein intake resulted in onset of ammoniuria and azoturia. (A) The chemical composition of urine based on dietary intake is hard to predict without taking into account the presence of dietary and urinary interferents; (B) the geographic isolation of patients studied underlines the importance of epigenetics in maintaining a traditional dietary heritage. (C) Moreover, the widespread use of food additives should consistently be taken into account to ensure a correct diagnosis of FKSF and set up a valid treatment plan.
饮食因素可能与肾结石的形成有关，应密切监测。为此，通过常规的饮食回顾评估患者，这是一种广泛应用于各种大型患者群体以记录食物摄入量的工具；然而，由于饮食变化和对食物添加剂影响的低估，所得结果可能存在偏差。从撒丁岛的 68 名患者中选择了 50 名常发性肾结石形成者（FKSF，平均年龄：54.3±13.9 岁），这些患者肾功能正常，无合并症，且具有可靠的依从性。这项研究于 2020 年 1 月 1 日至 2023 年 12 月 31 日进行，旨在根据食物数量、质量和与食物准备相关的潜在变化的详细记录来评估营养值。患者在初次临床检查时被选择，并尽一切努力确保他们能够可靠地记录所有消耗的食物和饮料。提供了一份为期七天的食物日记，记录食物和饮料的摄入量及其对 24 小时尿液输出的影响。在食物和尿液输出中测量了以下参数：柠檬酸盐、草酸盐、钙、磷、尿酸、蛋白质和氮化合物、镁、硫酸盐、钾、碳水化合物、游离脂肪酸。研究结果确定了低柠檬酸尿症、高草酸尿症、高钙尿症和中等水平的氮化合物的存在。进行了单变量分析，然后进行了多变量分析以进一步确认，并得出以下观察结果。柠檬酸摄入量与柠檬酸尿症相关，但不促进草酸尿症；钙摄入量促进了硫酸盐尿症、氮尿症和氨尿症的发生，而镁与镁尿症相关，但与草酸尿症、钙尿症、磷尿症和氮尿症无关；硫酸盐摄入量引起氮尿症，但不引起钾尿症；钾摄入量促进了草酸尿症，而蛋白质摄入量导致了氨尿症和氮尿症的发生。（A）如果不考虑饮食和尿液干扰物的存在，仅凭饮食摄入就很难预测尿液的化学成分；（B）研究患者的地理隔离强调了表观遗传学在维持传统饮食遗产方面的重要性。（C）此外，应始终考虑广泛使用食品添加剂，以确保正确诊断 FKSF 并制定有效的治疗计划。
