Use of the probability of stone formation (PSF) score to assess stone forming risk and treatment response in a cohort of Brazilian stone formers

Abstract

ARTICLE INFO ______________________________________________________________ ______________________Introduction: The aim was to confirm that PSF (probability of stone formation) changed appropriately following medical therapy on recurrent stone formers. Materials and Methods: Data were collected on 26 Brazilian stone-formers. A baseline 24-hour urine collection was performed prior to treatment. Details of the medical treatment initiated for stone-disease were recorded. A PSF calculation was performed on the 24 hour urine sample using the 7 urinary parameters required: voided volume, oxalate, calcium, urate, pH, citrate and magnesium. A repeat 24-hour urine sample was performed for PSF calculation after treatment. Comparison was made between the PSF scores before and during treatment.Results: At baseline, 20 of the 26 patients (77%) had a high PSF score (> 0.5). Of the 26 patients, 17 (65%) showed an overall reduction in their PSF profiles with a medical treatment regimen. Eleven patients (42%) changed from a high risk (PSF > 0.5) to a low risk (PSF < 0.5) and 6 patients reduced their risk score but did not change risk category. Six (23%) patients remained in a high risk category (> 0.5) during both assessments. Conclusions:The PSF score reduced following medical treatment in the majority of patients in this cohort.

Value of urinary metabolic study in patients with recurrent renal stones. Study in or a Health Area

“…La evaluación correcta del estudio está en relación entre otros factores con la recogida adecuada del mismo por parte del paciente (13), lo cual permite una orientación sobre la posible composición de la litiasis cuando no se dispone del análisis por espectrometría de infrarrojos y difracción de rayos X por los motivos que sean (14). La importancia del estudio metabólico no solo radica como hemos visto en los resultados del estudio, en el diagnóstico de alteraciones metabólicas, sino que es capaz de predecir la probabilidad de la formación de litiasis, lo cual influye de manera determinante en el tratamiento médico y seguimiento del paciente (15). En nuestra pequeña serie de pacientes de nuestra área de salud evaluados en un corto periodo de tiempo hemos demostrado que el estudio metabólico es de utilidad para el diagnóstico y poder establecer un tratamiento médico adecuado, que permita reducir el riesgo de recidiva litiásica y controlar la enfermedad.…”