Llamazares-Azuara L, Rodríguez-Martínez M, González-Castillo C, Blanco-Varela ML

Language: Spanish
References: 27
Page: 10-14
PDF size: 56.75 Kb.

ABSTRACT

Introduction: Amongst the 24 h urine preservation methods are those that consist in performing the urinre collection in containers containing acids or alcalis as the analyt of interest. That make necessary to perform several collections increasing the patient’s risks. Objective: To evaluate the effect of adding conservative before or after the 24 h urine collection on the concentration of creatinine, calcium, phosphorus, uric acid, oxalate and citrate. Methods: 25 voluntaries collected urine for 24 h. They isovolumetrically aliquoted each micturition into containers which contain (A = HCl, B = NaOH) or not conservator (C = SC). These containers were delivered in the lab before 2 h of the last micturition. The aliquotes A,B, and C were realliquoted (10 mL). The C container aliquotes were acidified (+HCl) or alcalinized (+NaOH), or added EDTA (+EDTA) or nor added any conservative (SC). All aliquotes were diluted, except in those in which citrate was measured, and then freezed. The determinations were done within 5-15 days. Results: The creatinine concentration was only subestimated with +NaOH method. Calcium, phosphorus,oxalate and uric acid were similar independently of the method. Citrate concentration was significantly lower with +NaOH method. Conclusions: To measure the concentration of analytes in previosuly acidified or alcalinized 24 h urine collections is unnecessary, since that the in situ addition of acid or alcali in the lab gives the same results without detriment in its reliability.

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