OBJECTIVES: This prospective study was initiated to assess the significance of spot urine specimens (SU) for the metabolic evaluation of stone formers. METHODS: 68 stone patients (51 males, 17 females) and 20 controls (9 males, 11 females) participated. On 3 consecutive days, urine was collected. Fasting (SU1) and postprandial (SU2) SU were obtained. From these, aliquots were taken, all the other urine was mixed to obtain 24-hour timed specimens (24hU). In all specimens, pH, specific gravity, creatinine, calcium, magnesium, phosphate, citrate, uric and oxalic acids were measured. The latter analytes were related to creatinine (mmol/g creatinine). Pearson correlation coefficients with their levels of significance and the day-to-day variation were calculated. Using the values in the control group, normal values (means +/- 2 SD) were established. RESULTS: There was a significant correlation (p < 0.0001) between SU and 24hU for all parameters examined. The day-to-day variation of all analytes was considerable in SU and 24hU. CONCLUSIONS: Despite a minor inaccuracy by relating parameters to creatinine, SU are sufficient in the routine metabolic evaluation of stone formers, since a third of all 24hU has to be rejected because of considerable collection errors. SU circumvent this problem. Because of the day-to-day variation, 3 SU should be obtained to overcome the doubtful significance of one single specimen.
OBJECTIVES: This prospective study was initiated to assess the significance of spot urine specimens (SU) for the metabolic evaluation of stone formers. METHODS: 68 stone patients (51 males, 17 females) and 20 controls (9 males, 11 females) participated. On 3 consecutive days, urine was collected. Fasting (SU1) and postprandial (SU2) SU were obtained. From these, aliquots were taken, all the other urine was mixed to obtain 24-hour timed specimens (24hU). In all specimens, pH, specific gravity, creatinine, calcium, magnesium, phosphate, citrate, uric and oxalic acids were measured. The latter analytes were related to creatinine (mmol/g creatinine). Pearson correlation coefficients with their levels of significance and the day-to-day variation were calculated. Using the values in the control group, normal values (means +/- 2 SD) were established. RESULTS: There was a significant correlation (p < 0.0001) between SU and 24hU for all parameters examined. The day-to-day variation of all analytes was considerable in SU and 24hU. CONCLUSIONS: Despite a minor inaccuracy by relating parameters to creatinine, SU are sufficient in the routine metabolic evaluation of stone formers, since a third of all 24hU has to be rejected because of considerable collection errors. SU circumvent this problem. Because of the day-to-day variation, 3 SU should be obtained to overcome the doubtful significance of one single specimen.
Authors: Pallavoor S Anandaram; Alan R De Bolla; Peter R Hudson; Gareth K Davies; Purnendu Majumdar; Clive P Williams Journal: Urol Res Date: 2006-05-06
Authors: Miguel Angel Arrabal-Polo; Salvador Arias-Santiago; María Sierra Girón-Prieto; Felix Abad-Menor; Fernando López-Carmona Pintado; Armando Zuluaga-Gomez; Miguel Arrabal-Martin Journal: Urol Res Date: 2012-04-07