Study of lithogenic factors in men and women with recurrent nephrolithiasis in the north area of Almeria

Objetivos: Estudiar los principales factores litogénicos en hombres y mujeres con litiasis urinaria recidivante en un área geográfica concreta. Material y Métodos: Estudio transversal que incluye 94 pacientes con litiasis urinaria recidivante desde junio 2014-enero 2015, en los que se realiza evaluación metabólica en sangre, orina ayunas y orina de 24 horas. Se comparan resultados medios de los parámetros estudiados según sexos y porcentaje de los principales factores de riesgo litogénicos. Estudio estadístico con SPSS 20.0, considerando significación estadística p≤0.05. Resultados: De los 94 pacientes incluidos, 60 fueron hombres y 34 mujeres, con edades medias de 49 y 51 años respectivamente, sin diferencias significativas. Los hombres presentan mayor excreción urinaria de calcio, úrico, oxalato y sodio que las mujeres y un mayor porcentaje de hiperuricosuria (>750 mg/24h) respecto a las mujeres. En las mujeres destaca en relación a los hombres un mayor porcentaje de hipovitaminosis D (<20ng/ml). La excreción de sodio se relaciona con la excreción de diferentes factores de riesgo litógeno, entre ellos el calcio. Los pacientes con pH en rango 5.5-7 presentan niveles de citrato más bajos que pacientes con pH<5.5. Conclusión:El estudio de factores litogénicos con evaluación metabólica tiene interés por los cambios que se producen según las regiones estudiadas y según otros factores como el sexo y el pH urinario.Objectives: To study the main lithogenic factors in men and women with recurrent nephrolithiasis in a particular geographical area. Material and Methods: Cross-sectional study including 94 patients with recurrent nephrolithiasis from June 2014 to January 2015, in which metabolic evaluation is performed on blood, fasting urine and 24 hours urine. Average results of the parameters studied by sex and percentage of the main lithogenic risk factors are compared. Statistical analysis with SPSS 20.0, considering statistical significance p≤0.05. Results: Of the 94 patients enrolled, 60 were men and 34 women, with mean ages of 49 and 51 years respectively, without significant difference. Men have higher urinary excretion of calcium, uric, sodium and oxalate respect women and men presented a higher percentage of hyperuricosuria (> 750 mg / 24 h) compared to women. In women, respect men, presented higher percentage of hypovitaminosis D (<20 ng / ml). Urinary sodium excretion is related to different lithiasis risk factors, including calcium. Patients with pH range 5.5-7 presented lower levels of citrate than patients with pH <5.5. Conclusion: The study of lithogenic factors with metabolic evaluation is interested in the changes that occur as the regions studied and according to other factors such as sex and urinary pH

Usefulness of measuring renal papillae in Hounsfield units in stone - forming patients

ABSTRACT Introduction: The aim of this work is to study the density of the renal papillae in stone-forming patients and to determine its usefulness. Materials and Methods: This study included a total of 79 patients diagnosed with renal stones and on whom a computed tomography without contrast was performed from June 2014 to May 2015. The patients were divided into two groups: Group 1 (single episode) included 43 patients, and Group 2 (recurrent episodes) included 36 patients. The density of six renal papillae (3 per kidney) was measured, and the means obtained were compared between Groups 1 and 2. Statistical analysis was performed using SPSS 20.0. Results: The mean papillary density in Group 1 was 32.26 (SD 4.07) HU compared to 42.36 (SD 8.03) HU in Group 2 (P=00001). A ROC curve was constructed, obtaining an optimal cut-off point of 36.8HU [area under the curve, 0.881 (95% CI; 0.804-0.958); P=0001], with a sensitivity of 80% and a specificity of 90%. The relative risk was estimated at 40.3 (95% CI; 10.8-151.1), meaning that a patient with a mean papillary density greater than 36.8HU would have a 40 times greater risk of having recurrent renal stones. The positive predictive value (PPV) was 81% and the negative predictive value (NPV) was 90%. Conclusion: The measurement of renal papillary density could be useful in predicting recurrent stone-formers. These results need to be confirmed in future studies with a greater number of patients and a longer follow-up

Usefulness of measuring renal papillae in Hounsfield units in stone - forming patients

ABSTRACT Introduction: The aim of this work is to study the density of the renal papillae in stone-forming patients and to determine its usefulness. Materials and Methods: This study included a total of 79 patients diagnosed with renal stones and on whom a computed tomography without contrast was performed from June 2014 to May 2015. The patients were divided into two groups: Group 1 (single episode) included 43 patients, and Group 2 (recurrent episodes) included 36 patients. The density of six renal papillae (3 per kidney) was measured, and the means obtained were compared between Groups 1 and 2. Statistical analysis was performed using SPSS 20.0. Results: The mean papillary density in Group 1 was 32.26 (SD 4.07) HU compared to 42.36 (SD 8.03) HU in Group 2 (P=00001). A ROC curve was constructed, obtaining an optimal cut-off point of 36.8HU [area under the curve, 0.881 (95% CI; 0.804-0.958); P=0001], with a sensitivity of 80% and a specificity of 90%. The relative risk was estimated at 40.3 (95% CI; 10.8-151.1), meaning that a patient with a mean papillary density greater than 36.8HU would have a 40 times greater risk of having recurrent renal stones. The positive predictive value (PPV) was 81% and the negative predictive value (NPV) was 90%. Conclusion: The measurement of renal papillary density could be useful in predicting recurrent stone-formers. These results need to be confirmed in future studies with a greater number of patients and a longer follow-up