Department of Paediatric Biochemistry, Royal Hospital for Sick Children, Edinburgh, Scotland, UK.
Ann Clin Biochem. 2010 Mar;47(Pt 2):125-30. doi: 10.1258/acb.2009.009146. Epub 2010 Feb 9.
Renal stones in children, although rare, may be associated with morbidity and renal damage. Scottish children have a different ethnic composition and diet compared with paediatric populations previously studied. Urinary stone promoters include calcium, oxalate and urate. Postulated inhibitors include citrate and glycosaminoglycans (GAGs). We tested the hypothesis that Scottish paediatric stone-formers have higher excretion of urinary stone promoters (calcium/oxalate/urate) and/or lower excretion of stone inhibitors (citrate/GAGs) than children with isolated haematuria and controls.
In this case-controlled study, we measured creatinine, calcium, oxalate, urate, citrate and GAGs in random urine samples from 24 stone-formers (excluding inherited metabolic disorders), median age 10.2 (range 1.0-17.2) y; 25 patients with isolated haematuria, 6.3 (0.6-13.7) y; and 32 controls, 7.5 (0.8-14.7) y.
Excretion of urinary promoters and inhibitors differed among stone-formers, haematuria and control groups for (median (range)): calcium (0.82 (0.02-2.19), 0.43 (0.08-2.65), 0.31 (0.04-2.12) mmol/mmol creatinine, respectively, P = 0.005), citrate (0.42 (0.13-0.72), 0.33 (0.05-0.84), 0.61 (0.11-1.75) mmol/mmol creatinine, P = 0.001), calcium:citrate ratio (1.68 (0.19-4.81), 1.30 (0.19-9.57), 0.54 (0.10-2.27) mmol/mmol, P < 0.0001) and the promoter:inhibitor ratio (calcium x oxalate)/(citrate x GAGs) (8.3 (1.0-82.5), 4.3 (1.2-69.5), 2.8 (0.3-13.2) mmol/g, P < 0.0001).
Scottish paediatric stone-formers had lower urinary citrate excretion and higher urinary calcium excretion, calcium:citrate ratio and promoter:inhibitor ratio compared with controls. Urinary calcium excretion and promoter:inhibitor ratio was also higher than children with isolated haematuria. Nevertheless, marked overlap between the stone-former and haematuria groups for promoter:inhibitor and calcium:citrate ratios suggests that some patients with isolated haematuria may be at future risk of urolithiasis.
儿童肾结石虽然少见，但可能与发病率和肾损伤有关。与之前研究的儿科人群相比，苏格兰儿童的种族构成和饮食不同。尿石促进剂包括钙、草酸和尿酸。推测的抑制剂包括柠檬酸盐和糖胺聚糖（GAGs）。我们检验了苏格兰儿科结石患者的尿石促进剂（钙/草酸/尿酸）排泄更高和/或结石抑制剂（柠檬酸盐/GAGs）排泄更低的假设，与单纯血尿和对照组相比。
在这项病例对照研究中，我们测量了 24 名结石患者（不包括遗传性代谢紊乱）的随机尿样中的肌酐、钙、草酸、尿酸、柠檬酸盐和 GAGs，中位年龄为 10.2（范围 1.0-17.2）岁；25 名单纯血尿患者，6.3（0.6-13.7）岁；32 名对照组，7.5（0.8-14.7）岁。
结石患者、血尿患者和对照组的尿促进剂和抑制剂排泄存在差异（中位数（范围））：钙（0.82（0.02-2.19）、0.43（0.08-2.65）、0.31（0.04-2.12）mmol/mmol 肌酐，分别，P = 0.005），柠檬酸盐（0.42（0.13-0.72）、0.33（0.05-0.84）、0.61（0.11-1.75）mmol/mmol 肌酐，P = 0.001），钙：柠檬酸盐比值（1.68（0.19-4.81）、1.30（0.19-9.57）、0.54（0.10-2.27）mmol/mmol，P < 0.0001）和促进剂：抑制剂比值（钙 x 草酸）/（柠檬酸盐 x GAGs）（8.3（1.0-82.5）、4.3（1.2-69.5）、2.8（0.3-13.2）mmol/g，P < 0.0001）。
与对照组相比，苏格兰儿科结石患者的尿柠檬酸盐排泄较低，尿钙排泄、钙：柠檬酸盐比值和促进剂：抑制剂比值较高。尿钙排泄和促进剂：抑制剂比值也高于单纯血尿患者。然而，结石患者和血尿患者的促进剂：抑制剂比值和钙：柠檬酸盐比值之间存在显著重叠，表明一些单纯血尿患者未来可能有患尿路结石的风险。
