Chronic interstitial nephritis of nontraditional causes in Salvadoran agricultural communities.

In El Salvador, a form of chronic kidney disease (CKD) of nontraditional causes (CKDnt) affecting farmers is being reported. Its behavior has been epidemic and is responsible for tens of thousands of deaths. This article summarizes the results obtained from a series of studies conducted to identify the epidemiology and clinical behavior of this disease, proposing a case definition and an etiopathogenic hypothesis. Methods included a survey of CKD in agricultural communities studying 2,388 people ≥ 18 years and 1,755 < 18, a descriptive clinical study followed by histopathological assessment conducted in 46 possible cases of CKDnt ≥ 18 years, and a national survey to study the prevalence of CKD and associated risk factors in 4,817 participants ≥ 20 years followed by a nested case-control study. In the agricultural communities, the prevalence of CKD in adults was 18% (men: 23.9%, women: 13.9%), 26.8% in agricultural workers (non-agricultural 13.8%), CKDnt accounted for 51.9% of cases. CKD in the population < 18 years was 3.9% (mean estimated glomerular filtration rate > 160 mL/1.73m2). The national CKD prevalence was 12.6% (urban: 11.3%; rural: 14.4%; males: 17.8%, females 8.5%), and CKDnt was only 3.8%; with associations between CKD and exposure to agrochemicals. The clinical study revealed the presence of markers of kidney damage (A3 albuminuria: 80.4%; ß2-microglobulin: 78.2%), urine electrolyte anomalies (100% hypermagnesuria, 45.7% hypernatriuria, 43.5% osmotic polyuria), abnormal osteotendinous reflexes (45.7%), sensorineural hearing loss (56.5%), and damage of the tibial arteries by Doppler imaging (66.7%). Biopsies revealed a chronic tubulointerstitial nephropathy. The etiopathogenesis of CKDnt is possibly multifactorial, including environmental contamination by agrochemicals, heat stress, and dehydration.

Thrombotic Microangiopathy in Patients Recovering from COVID-19.

INTRODUCTION: During the pandemic caused by the SARS-CoV-2 virus, some patients who develop severe forms of COVID-19 present thrombotic microangiopathy in the course of the disease's clinical progression. METHODS: Data came from direct patient observation and clinical records. We performed a kidney biopsy and used optical microscopy and immunofluorescence techniques. RESULTS: We present the case of a 78-year-old male patient, mestizo, overweight with a history of high blood pressure, ischemic cardiopathy and chronic obstructive pulmonary disease who was first admitted to the hospital due to respiratory symptoms and diarrhea related to COVID-19, from which he recovered. He was subsequently readmitted with symptoms of acute renal dysfunction accompanied by mild anemia and thrombocytopenia; at the same time, he resulted negative for COVID-19 via a real-time polymerase chain reaction test. A kidney biopsy revealed thrombi in glomerular capillaries, acute tubular necrosis, thickening of extraglomerular blood vessel walls, and C3 deposits in the glomerular tufts. CONCLUSIONS: We describe a case of thrombotic microangiopathy with kidney biopsy in a patient recovering from COVID-19. Acute renal dysfunction is a form of thrombotic microangiopathy that has been observed in patients recovering from COVID-19.

Urinary Metabolic Disorders Associated with Urolithiasis in Cuban Pediatric Patients.

INTRODUCTION: Pediatric urinary lithiasis (urolithiasis) is an important health issue linked to urinary metabolic disorders. In the United States alone, annual costs associated with urolithiasis are $229 million for hospital admissions and $146 million for emergency care. OBJECTIVE: Identify urinary metabolic disorders in Cuban pediatric patients with urolithiasis and better understand the relationship of age, demographic and anthropometric variables to urinary metabolic disorders strongly associated with urolithiasis. METHODS: We carried out a descriptive, cross-sectional study. The study universe was comprised of Cuban patients aged 2 to 19 years with urinary lithiasis who underwent renal metabolic studies at the Dr Abelardo Buch López Nephrology Institute in Havana, Cuba, from 2008 through 2019. All data were obtained from reports of the aforementioned metabolic studies. We collected the following variables: age, sex, nutritional status, urinary volume, plasma and urinary creatine concentrations; and calcium, uric acid, oxalate and citrate urinary excretions collected during a 24-hour period. We included results of urinary cystine tests and urine mini-cultures. We obtained frequency distributions for categorical and qualitative variables and calculated means and standard deviations for quantitative variables. We also evaluated homogeneity of metabolic disorders between children and adolescents. RESULTS: We studied 1592 pediatric patients, of whom 67.7% (1078/1592) were adolescents. The main metabolic disorders included hypercalciuria (39.1%; 622/1592), decreased urinary flow (22.4%; 357/1592) and hypocitraturia (18.2%; 289/1592). Hypercalciuria, hypocitraturia and hyperoxaluria were more common in children, while decreased urinary flow and hyperuricosuria were more common in adolescents. Hyperuricosuria was more frequent in male patients (6.3%; 40/639 vs. 1.8%; 8/439) and had the greatest impact on lithogenesis. Hypercalciuria was more frequent in undernourished children (62.5%; 30/48) than in overweight children (21.7%; 10/46), or those with obesity (33.3%; 15/45). CONCLUSIONS: The main metabolic disorders among Cuban pediatric patients with urinary lithiasis are: hypercalciuria, decreased urinary flow and hypocitraturia. Hypercalciuria, hypocitraturia and hyperoxaluria are more common in children, and decreased urinary flow and hyperuricosuria are more common in adolescents. Identifying urinary metabolic disorders facilitates formulation of treatment plans tailored to decreasing the likelihood of urolithiasis.

COVID-19 and the Kidneys: Risk, Damage and Sequelae.

At fi rst, COVID-19 was thought to be primarily a respiratory disease, progressing in some patients to serious respiratory symptoms, pneumonia, severe respiratory distress syndrome and even death. Later analysis revealed entire systems were compromised, affecting other vital organs, including the kidneys, and a correlation was observed between chronic kidney disease (CKD) and COVID-19 severity COVID-19 severity.

Semi-Mechanistic Pharmacokinetic Model to Guide the Dose Selection of Nimotuzumab in Patients with Autosomal Dominant Polycystic Kidney Disease.

Autosomal dominant polycystic kidney disease (ADPKD) is a genetic disease characterized by an overexpression of epidermal growth factor receptor (EGFR). Nimotuzumab is a recombinant humanized monoclonal antibody against human EGFR. The aim of this study was to develop a population pharmacokinetic model for nimotuzumab and to identify demographic and clinical predictive factors of the pharmacokinetic variability. The population pharmacokinetics (PopPK) of nimotuzumab was characterized using a nonlinear mixed-effect modeling approach with NONMEM®. A total of 422 log-transformed concentration-versus-time datapoints from 20 patients enrolled in a single-center phase I clinical trial were used. Quasi steady state approximation of the full TMDD (target-mediated drug disposition) model with constant target concentration best described the concentration-time profiles. A turnover mediator was included which stimulates the non-specific clearance of mAb in the central compartment in order to explain the reduced levels at higher doses. Covariates had no influence on the PK (pharmacokinetics) parameters. The model was able to detect that the maximum effective dose in ADPKD subjects is 100 mg. The developed PopPK model may be used to guide the dose selection for nimotuzumab during routine clinical practice in patients with polycystic kidney disease. The model will further support the ongoing investigations of the PK/PD relationships of nimotuzumab to improve its therapeutic use in other disease areas.

Epidemic of Chronic Kidney Disease of Nontraditional Etiology in El Salvador: Integrated Health Sector Action and South-South Cooperation.

In El Salvador, chronic kidney disease had reached epidemic propor-tions towards the end of this century's first decade. In 2011-2012, the Ministry of Health reported it was the leading cause of hospital deaths in men, the fifth in women, and the third overall in adult hospital fa-talities. Farming was the most common occupation among men in dialysis (50.7%). By 2017, chronic kidney disease admissions had overwhelmed hospital capacity.In 2009, El Salvador's Ministry of Health, Cuba's Ministry of Public Health and PAHO launched a cooperative effort to comprehensively tackle the epidemic. The joint investigations revealed a total prevalence of chronic kidney disease in the adult population of farming communities higher than that reported internationally (18% vs.11%-14.8%), higher in men than in women (23.9% vs 13.9%) and higher in men who were farmers/farmworkers than in men who were not (31.3% vs. 14.8%). The disease was also detected in children. An association was found between chronic kidney disease and exposure to agrochemicals (OR 1.4-2.5). In 51.9% of all chronic kidney disease cases, traditional causes (diabetes, hyperten-sion, glomerulopathies, obstructive nephropathies and cystic diseases) were ruled out and the existence of a particular form of chronic kidney disease of nontraditional etiology was confirmed (whose initial cases were reported as early as 2002). In the patients studied, functional altera-tions and histopathologic diagnosis confirmed a chronic tubulointerstitial nephritis; most presented with neurosensory hearing loss, altered tendon refiexes and tibial artery damage. The main results of this cooperation were the epidemiologic, physio-pathologic, clinical and histopathologic characterization of chronic kid-ney disease of nontraditional etiology. This characterization facilitated case definition for the epidemic and led to the hypothesis of systemic toxicity from agrochemicals (e.g., paraquat, glyphosate), which par-ticularly affect the kidneys and to which farmers/farmworkers (who may also become dehydrated in the fields) are most exposed. The research thus also laid the foundations for design of comprehensive intersectoral government actions to reduce cases and put an end to the epidemic. KEYWORDS Chronic kidney disease; chronic renal failure; tubuloint-erstitial nephritis; epidemiology; histopathology; international coopera-tion; agrochemicals; environmental pollutants, noxae, and pesticides; occupational health; PAHO; El Salvador; Cuba.

Pharmacokinetic Evaluation of Nimotuzumab in Patients With Autosomal Dominant Polycystic Kidney Disease.

Autosomal dominant polycystic kidney disease (ADPKD) is a genetic disease characterized by an overexpression and mislocalization of epidermal growth factor receptor (EGFR) to the apical membranes of cystic epithelial cells. Nimotuzumab is a humanized antibody that recognizes an extracellular domain III of human EGFR. The aim of this study was to assess the pharmacokinetic behavior of nimotuzumab in patients with ADPKD given as a single dose. A phase I, single-center, and noncontrolled open clinical study was conducted. Five patients were enrolled at each of the following fixed-dose levels: 50, 100, 200, and 400 mg. Intravenous continuous infusions of nimotuzumab were administered every 14 days during a year, except the first administration, when blood samples were drawn during 28 days for pharmacokinetic assessments. Subjects were closely monitored during the trial and at completion of the administration of nimotuzumab, including the anti-idiotypic response. For the first time, nimotuzumab was used for treating a nononcological disease. The administration of nimotuzumab showed dose-dependent kinetics. Nimotuzumab does not develop anti-idiotypic response against the murine portion present in the hypervariable region of the antibody present in the serum of the patients treated. No significant differences were found in the systemic clearance between the 100- and 400-mg dose, which indicates that the optimal biological dose is in this range of dose.

Caracterización clínico-epidemiológica de la urolitiasis / Clinical-epidemiological description of urolithiasis

Introducción: Las urolitiasis ocasionan dolor, deterioro funcional renal y notorias erogaciones económicas. Objetivos: Identificar las características clínico-epidemiológicas de la nefrolitiasis. Métodos: Estudio descriptivo, transversal. Se estudiaron 2 923 personas pertenecientes a tres consultorios del Policlínico Plaza; municipio Plaza de la Revolución, provincia La Habana, Cuba., seleccionados por muestreo simple aleatorio de los 16 con que cuenta el área de salud. Los datos se obtuvieron mediante encuesta y entrevista estructurada. La información fue procesada de forma automatizada (IBMSPSS 22.0). Se utilizó análisis de distribución de frecuencias, se calcularon tasas de prevalencia, y fue empleado el test de homogeneidad. Resultados: La prevalencia de urolitiasis fue de 4,99 por cada 100 habitantes, de 6,3 entre los varones y de 5,7 en los de piel blanca. La edad promedio al diagnóstico fue de 39,3 años. Entre los factores de riesgo de litiasis predominó la alta ingestión de oxalatos (97,3 por ciento). La ecografía fue la forma de diagnóstico más usada (67,8 por ciento). La fitoterapia fue el tratamiento médico más utilizado (69,2 por ciento). Al 16,4 por ciento de los pacientes se les expidió certificado médico en los últimos dos años. Conclusiones: La prevalencia de litiasis urinaria en el Policlínico Docente Plaza de la Revolución es elevada, con predominio en el sexo masculino, en sujetos de piel blanca y en las edades medias de la vida. La alta ingestión de oxalato es el factor de riesgo de litiasis urinaria más frecuente encontrado. La forma de diagnóstico más utilizada es la ecografía y el tratamiento más empleado es la fitoterapia(AU)

Introduction: Urolithiasis causes pain, renal functional deterioration and notorious economic expenses. Objectives: To identify the clinical-epidemiological characteristics of nephrolithiasis. Methods: A descriptive, cross-sectional study was conducted in a total of 2,923 people from to three clinics of Plaza de la Revolution Teaching Community Clinic, Plaza de la Revolution municipality, Havana province, Cuba. They were selected by simple random sampling from the 16 clinics that the health area has. The data was obtained through a survey and structured interview. The information was processed automatically (IBMSPSS 22.0). Frequency distribution analysis was used, prevalence rates were calculated and the homogeneity test was used. Results: The prevalence of urolithiasis was 4.99 per 100 inhabitants, 6.3 among men and 5.7 among white-skinned men. The average age at diagnosis was 39.3 years. Among the risk factors for lithiasis, the high intake of oxalates prevailed (97.3 percent). Ultrasound was the most used form of diagnosis (67.8 percent). Phytotherapy was the most used medical treatment (69.2 percent). A medical permit was issued to 16.4 percent of the patients in the last two years. Conclusions: The prevalence of urinary lithiasis in Plaza de la Revolution Teaching Community Clinic is high, prevailing in males, in white-skinned and middle aged subjects. High oxalate intake is the most common risk factor for urinary lithiasis found. The most used form of diagnosis is ultrasound and the most used treatment is phytotherapy(AU)

Composición de las urolitiasis y trastornos metabólicos renales en adultos cubanos

Introducción: La litiasis urinaria es una enfermedad común, cuya prevalencia se incrementa a escala nacional y planetaria. Objetivos: Conocer la composición de las urolitiasis en pacientes adultos cubanos y su relación con los trastornos metabólicos renales. Métodos: Estudio descriptivo, transversal. Universo constituido por los pacientes cubanos de 19 años y más de edad, que se realizaron estudio de composición de urolitiasis en el Instituto de Nefrología "Dr. Abelardo Buch", de La Habana, Cuba, en el período comprendido de 2011-2020. De ellos 443 se habían realizado estudio metabólico renal. Los datos fueron recogidos de los informes de resultados, de composición de litiasis y de estudio metabólico. Se utilizó análisis de distribución de frecuencias, y para identificar las relaciones, el test independencia. Resultados: En cuanto a la composición química, predominaron las litiasis de oxalato de calcio. Los trastornos metabólicos más frecuentes fueron excreción de sodio aumentada (46,7 %) y volumen urinario bajo (29,3 %). La frecuencia de pacientes con litiasis cálcicas, fue superior en los que tuvieron excreción de sodio aumentada (78,3 %), y en los que presentaron hipercalciuria (83,3 %), en contraste con las frecuencias de este tipo de litiasis, en los que no presentaron dichos trastornos (p=0,03 en ambos casos). Conclusiones: Las urolitiasis más comunes en adultos cubanos son las cálcicas, especialmente las de oxalato de calcio. Los trastornos metabólicos más frecuentes son: excreción urinaria aumentada de sodio, volumen urinario bajo y pH urinario ácido. La presencia de litiasis cálcicas se relaciona con excreción urinaria aumentada de sodio y con hipercalciuria.

Introduction: Urinary lithiasis is a common disease, whose prevalence is increasing on a national and planetary scale. Objectives: To know the composition of urolithiasis in Cuban adult patients and its relationship with renal metabolic disorders. Methods: Descriptive, cross-sectional study. Universe constituted by Cuban patients aged 19 and over, who underwent a composition study of urolithiasis at the "Dr. Abelardo Buch" Institute of Nephrology, in Havana, Cuba, in the period 2011-2020. In 443 of them, a renal metabolic study had also been carried out. The data were collected from the results reports of stone composition and metabolic study. Frequency distribution analysis was used, and the independence test was used to identify relationships. Results: Regarding chemical composition, calcium oxalate stones predominated. The most frequent metabolic disorders were increased sodium excretion (46.7%) and low urine volume (29.3%). The frequency of patients with calcium stones was higher in those with increased sodium excretion (78.3%) and in those with hypercalciuria (83.3%), in contrast with the frequencies of this type of lithiasis, in those who did not present these disorders (p=0.03 in both cases). Conclusions: The most common urolithiasis in Cuban adults are calcium ones, especially those of calcium oxalate. The most common metabolic disorders are: increased urinary sodium excretion, low urinary volume and acid urinary pH. The presence of calcium lithiasis is related to increased urinary sodium excretion and hypercalciuria.

Trastornos metabólicos urinarios en pacientes urolitiásicos con enfermedad renal poliquística y sin ella / Urinary metabolic disorders in urolithiasis patients with and without polycystic kidney disease

Introducción: La urolitiasis se ha incrementado en las últimas décadas. La enfermedad renal poliquística autosómica dominante (ERPAD), enfermedad renal hereditaria más frecuente, ocupa un lugar preponderante. Objetivos: Identificar la frecuencia de presentación de los trastornos metabólicos urinarios en pacientes litiásicos cubanos con ERPAD y sin ella Métodos: Estudio descriptivo, transversal. Fueron estudiados 579 pacientes adultos sin ERPAD, seleccionados por muestreo simple aleatorio y los 21 pacientes con ERPAD, del total de pacientes con litiasis urinaria que se realizó estudio metabólico renal en el Laboratorio de Fisiopatología Renal del Instituto de Nefrología, en el periodo 2010-2015. Los datos fueron tomados de la historia clínica y del informe de estudio metabólico renal. La información se procesó de forma automatizada (SPSS 22.0). Se utilizó el promedio, desviación estándar, análisis de distribución de frecuencias y el test de homogeneidad. Resultados: En los pacientes con ERPAD predominó el sexo femenino (57,1 por ciento), mientras que en los pacientes sin ERPAD, el masculino (63,4 por ciento). Los trastornos más frecuentes en la población no poliquística fueron hipercalciuria (45,3 por ciento) e hipofosfatemia (17,1 por ciento). En los poliquísticos, aclaramiento aumentado de ácido úrico (38,1 por ciento) e hipercalciuria (23,8 por ciento). Se encontraron diferencias estadísticamente significativas para aumento del aclaramiento de ácido úrico (p = 0,01) e hiperfosfatemia (p = 0,04). Conclusiones: Los principales trastornos metabólicos de los pacientes litiásicos, tanto poliquísticos como no poliquísticos, son el aclaramiento de ácido úrico aumentado, hipercalciuria, hiperuricosuria e hipofosfatemia, aunque el orden de presentación es diferente. El aclaramiento de ácido úrico aumentado y la hiperfosfatemia se presentan con mayor frecuencia en los pacientes litiásicos poliquísticos(AU)

Introduction: Urolithiasis has increased in recent decades. Autosomal dominant polycystic kidney disease (ADPKD), the most common of all hereditary kidney diseases, occupies a predominant position in terms of incidence. Objectives: Identify the frequency of occurrence of urinary metabolic disorders in Cuban urolithiasis patients with and without ADPKD. Methods: A descriptive cross-sectional study was conducted of 579 adult patients without ADPKD selected by simple random sampling, and 21 patients with ADPKD, from the total urolithiasis patients undergoing renal metabolic evaluation at the Renal Physiopathology Laboratory of the Institute of Nephrology in the period 2010-2015. Data were obtained from medical records and reports of renal metabolic studies. Information was processed with the statistical software SPSS version 22.0. Average and standard deviation were estimated and use was made of frequency distribution analysis and homogeneity testing. Results: A predominance was found of female sex among patients with ADPKD (57.1 percent) and male sex among patients without ADPKD (63.4 percent). The most common disorders were hypercalciuria (45.3 percent) and hypophosphatemia (17.1 percent) in the non-polycystic population, and increased uric acid clearance (38.1 percent) and hypercalciuria (23.8 percent) in polycystic patients. Statistically significant differences were found in uric acid clearance increase (p = 0.01) and hyperphosphatemia (p = 0.04). Conclusions: The main metabolic disorders of lithiasis patients, polycystic as well as non-polycystic, are increased uric acid clearance, hypercalciuria, hyperuricosuria and hypophosphatemia, with a varying order of presentation. Increased uric acid clearance and hyperphosphatemia are more common in polycystic lithiasis patients(AU)

Hallazgos ultraestructurales renales de pacientes con nefritis intersticial crónica de las comunidades agrícolas en El Salvador / Renal ultrastructural findings of patients with chronic interstitial nephritis from farming communities in El Salvador

Introducción: Desde hace 20 años se presenta en Centroamérica una enfermedad renal crónica que fundamentalmente afecta a hombres agricultores y no asociada a las causas tradicionales. Se caracteriza por presentar una nefritis intersticial crónica, en tanto las características ultraestructurales no se conocen con exactitud. En su origen se invoca el uso de agroquímicos y otros agentes nefrotóxicos, la deshidratación crónica, el consumo de medicamentos, entre otros factores. Objetivo: Describir las características ultraestructurales de la nefritis intersticial crónica en comunidades agrícolas. Método: Se realizó un estudio descriptivo de corte transversal. Se estudiaron muestras de biopsias renales de ocho pacientes con diagnóstico de nefritis intersticial crónica de las comunidades agrícolas. Resultados: De los ocho pacientes estudiados, dos (25 por ciento) trabajaban en labores agrícolas y cinco eran del sexo femenino (62,5 por ciento). Dos de los pacientes (25 por ciento) presentaban una enfermedad renal crónica estadio 2, y seis (75 por ciento) estadio 3. En cinco pacientes se hallaron fagolisosomas con presencia de componente lipídico entremezclado con material electrodenso en células del túbulo distal. En igual cantidad de pacientes se observaron cuerpos mieloides con zonas laminadas y núcleo central en células de túbulo proximal y de los vasos sanguíneos. Conclusiones: En pacientes de comunidades agrícolas que padecen nefritis intersticial crónica se evidencian fagolisosomas y estructuras mieloides en túbulos y vasos renales, cuyo contenido y origen se desconocen(AU)

Introduction: Chronic kidney disease mainly affecting male farmers and not associated to traditional causes has been present in Central America for twenty years. The condition is characterized by the presence of chronic interstitial nephritis, but its ultrastructural features are not fully known. Factors suggested as responsible for its occurrence include the use of agrochemicals and other nephrotoxic agents, chronic dehydration and medicine consumption. Objective: Describe the ultrastructural characteristics of chronic interstitial nephritis in farming communities. Method: A cross-sectional descriptive study was conducted of renal biopsy samples from eight patients diagnosed with chronic interstitial nephritis in farming communities. Results: Of the eight patients studied, two (25 percent) were farm workers and five (62.5percent) were female. Two of the patients (25 percent) had stage 2 and six (75 percent) stage 3 chronic kidney disease. In five patients evidence was found of phagolysosomes with lipid component mixed with electrodense material in distal tubule cells. An equal number of patients had myeloid bodies with laminated areas and central nucleus in proximal tubule and blood vessel cells. Conclusions: Evidence of phagolysosomes and myeloid structures of unknown content and origin was found in renal tubules and vessels of patients from farming communities diagnosed with chronic interstitial nephritis(AU)

Síndrome de nefritis tubulointersticial y uveítis / Interstitial Tubule Nephritis Syndrome and Uveitis

El síndrome de nefritis tubulointersticial y uveítis es una causa infrecuente de disfunción renal aguda en los adultos. El diagnóstico puede hacerse difícil, pues con frecuencia no coinciden temporalmente los síntomas oculares y renales. Se presentaron dos casos de síndrome de nefritis tubulointersticial y uveítis en adultos, con evolución favorable con tratamiento esteroideo sistémico(AU)

Tubulointerstitial nephritis syndrome and uveitis is an uncommon cause of acute renal dysfunction in adults. The diagnosis can be difficult, as ocular and renal symptoms often do not coincide temporarily. Two cases of tubulointerstitial nephritis syndrome and uveitis in adults, with favorable evolution with systemic steroid treatment are presented in this paper(AU)

Variabilidad anatómica de la vena yugular interna por ecografía en voluntarios sanos y pacientes en hemodiálisis / Anatomical variation of internal jugular vein by sonography in healthy volunteers and patients on hemodialysis

Introducción: se han descrito varias técnicas para canalizar la vena yugular interna, pero su canulación sobre la base de las referencias anatómicas tropieza con la variabilidad anatómica. Objetivo: identificar la disposición anatómica de los vasos del cuello en voluntarios sanos y en pacientes en hemodiálisis crónica y su relación con variables demográficas, antropométricas y clínicas. Métodos: estudio observacional, analítico, transversal, de individuos aparentemente sanos que asistieron al Servicio de Ultrasonido, entre mayo de 2011 y agosto de 2012, y todos los pacientes en hemodiálisis del Instituto de Nefrología. Se realizó ecografía por RABM, con equipo Toshiba Nemio XG Model SSA-580A con efecto Doppler, utilizando transductor lineal de 7,5 MHz. Las comparaciones iniciales entre los grupos fueron realizadas mediante el test de homogeneidad o la prueba t para muestras independientes. Para identificar la posible relación de la disposición de los vasos del cuello y las características estudiadas se utilizó el test de independencia. Resultados: más del 74 por ciento de los individuos de ambos grupos presentó una posición anatómica adecuada de las vena yugular interna. La variación más frecuente en los dos grupos fue la cabalgadura parcial; desde 6,1 por ciento en el hemicuello derecho de los voluntarios sanos, hasta 12 por ciento en el hemicuello izquierdo de los pacientes en hemodiálisis. Solo en los pacientes en hemodiálisis se encontró asociación entre el antecedente de más de 3 abordajes venosos con la variación anatómica de la vena yugular interna, tanto derecha (p= 0,04), como izquierda (p= 0,00)(AU)

Introduction: several techniques have been described for channeling the internal jugular vein, but the approach based on the anatomical references encounters anatomical variability. Objective: identify the anatomical arrangement of the neck vessels in healthy volunteers and in patients who hemodialysis for long, and its relationship to demographic, anthropometric and clinical variables applied. Methods: an observational, analytical, cross study was conducted in apparently healthy individuals who attended the ultrasound service, from May 2011 to August 2012, and in all hemodialysis patients at the Nephrology Institute. Ultrasonography was performed by AMFN, with Nemio XG Toshiba Model SSA-580A Doppler Effect, using 7.5 MHz linear transducer. The initial comparisons between groups were performed using the homogeneity test or t test for independent samples. Chi-Square Test of Independence was used to identify the possible relationship of the arrangement of the neck vessels and the characteristics studied. Results: more than 74 percent of patients in both groups presented a proper anatomical position of the internal jugular vein. The most frequent variation in the two groups was the partial overriding from 6.1 percent of right hemi-neck in healthy volunteers to 12 percent of left hemi-neck in patients on hemodialysis. Only in hemodialysis patients association was found between a history of more than 3 venous approaches to anatomical variation of the internal jugular vein, both right (p = 0.04) and left (p = 0.00)(AU)

Composición de las urolitiasis en pacientes cubanos por sexo / Composition of urolithiasis in Cuban patients by sex

INTRODUCCIÓN: las urolitiasis implican morbilidad y costos económicos sustanciales. Para su manejo resulta fundamental una evaluación clínica y de laboratorio, que incluya el estudio de la composición química. OBJETIVO: determinar la frecuencia de presentación de los diferentes tipos de urolitiasis según su composición y su relación con el sexo de los sujetos. MÉTODOS: estudio descriptivo, transversal. Se incluyeron las urolitiasis de adultos cubanos, enviadas al Laboratorio de Fisiopatología Renal del Instituto de Nefrología para estudio de composición química, en el período 2001-2011. Las litiasis fueron analizadas con un espectroscopio infrarrojo modelo Philips PU9516. Los diferentes compuestos se identificaron mediante comparación con espectros de referencia. Toda la información fue procesada automatizada (SPSS 15.0.). Se utilizó análisis de distribución de frecuencias. Para probar la existencia de diferencias entre los sexos, en cuanto al tipo de litiasis, se emplearon los tests: de independencia y exacto de Fisher. RESULTADOS: de las 1851 litiasis analizadas, 1316 (71,1 %) eran litiasis simples. Las litiasis simples de oxalato de calcio constituyeron el 46,8 % del total. Dentro de las compuestas, las más frecuentes fueron las de oxalato de calcio más fosfato de calcio (24,7 %). La frecuencia de las litiasis de oxalato de calcio y ácido úrico resultó mayor entre los hombres (p= 0,00), y las de fosfato de calcio y de estruvita (p= 0,00), entre las mujeres. CONCLUSIONES: los cálculos cálcicos, fundamentalmente de oxalato de calcio monohidratado, son los más comunes en la población litiásica estudiada. Las litiasis de oxalato de calcio y ácido úrico son más comunes entre los hombres, mientras las de estruvita y fosfato de calcio lo son, entre las mujeres.

INTRODUCTION: urolithiasis imply significant morbidity and economic costs. For its management, it is fundamental to make clinical and lab evaluation including the study of the chemical composition. OBJECTIVE: to determine the frequency of occurrence of several types of urolithiasis according to their composition and relationship with the individual's sex. METHODS: descriptive and cross-sectional study that included urolithiasis of Cuban adults sent to the Renal Physiopathology Lab of the Institute of Nephrology for the study of chemical composition in the 2001-2011 period. A Philips PU9516 infrared spectroscope served to analyze lithiasis. The various compounds were identified by comparing them with the reference spectra. All the data were collected and processed with SPSS 15.0; the frequency distribution analysis. Independence test and Fisher's exact test were used to confirm the differences between sexes in terms of type of lithiasis. RESULTS: of 1815 analyzed lithiasis, 1316 (71.1 %) were simple. Simple calcium oxalate lithiasis represented 46.8 % of the total number. In the combinations, the most frequent were calcium oxalate plus calcium phosphate (24.7 %). The frequency of calcium oxalate and uric acid lithiasis was higher in men (p= 0.00 and those of calcium phosphate and struvite (p= 0.00) in women. CONCLUSIONS: calcium stones, mainly monohydrated calcium oxalate, are the most common in the studied lithiatic population. Calcium oxalate and uric acid are the commonest in men whereas struvite and calcium phosphate are more frequent in women.

pH urinario y estado nutricional en pacientes cubanos con urolitiasis / Urinary pH and nutritional status in Cuban ptients with urolithiasis

INTRODUCCIÓN: la obesidad y las urolitiasis son problemas crecientes en el mundo. El pH urinario ácido (bajo) predispone a las urolitiasis. OBJETIVO: determinar la posible relación entre el peso corporal y el índice de masa corporal con el pH urinario en pacientes litiásicos. MÉTODOS: estudio observacional analítico transversal en el que se incluyeron todos los pacientes litiásicos adultos cubanos que se hicieron estudio metabólico renal en el Instituto de Nefrología entre enero de 2011 y diciembre de 2012, que no presentaran ninguna condición con reconocida influencia sobre el pH urinario. Se midió el pH urinario y se hizo minicultivo con una muestra de orina en ayunas. Se midió el peso, la talla y se calculó el índice de masa corporal. La información se procesó mediante el paquete estadístico SPSS versión 15.0. Fue calculada la media, la desviación estándar, máximo y mínimo de edad, peso e índice de masa corporal. Las comparaciones entre las variables se hicieron por análisis de varianza. RESULTADOS: fueron estudiados 1 724 pacientes con una edad promedio de 41,6 años y una relación hombre/mujer de 2,1/1. El pH urinario medio disminuyó 0,23 unidades del sextil de menos peso corporal al de mayor peso (p= 0,00). El pH urinario medio fue de 5,69 en desnutridos y normopesos, en sobrepesos fue de 5,59 y de 5,53 en obesos (p= 0,00). CONCLUSIÓN: el pH urinario en ayunas tiene una relación inversa con el peso corporal y el índice de masa corporal en pacientes adultos con litiasis urinarias sin infección del tracto urinario.

INTRODUCTION: obesity and urolithiasis are growing problems in the world. The acid (low) urinary pH predisposes urolithiasis. OBJECTIVE: determine the possible relationship between body weight and body mass index (BMI) with urinary pH in patients with kidney stones. METHODS: a cross-sectional observational study was conducted in all Cuban adults lithiasic patients who underwent renal metabolic study at the Nephrology Institute from January 2011 to December 2012, and who did not have any conditions with recognized influence on urinary pH. Urinary pH was measured and a mini-culture was performed on a fasting urine sample. Weight, height and body mass index were registered. The information was processed using SPSS version 15.0. Mean age, standard deviation of minimum and maximum age, weight and body mass index were calculated. Comparisons between variables were made by analysis of variance. RESULTS: 1 724 patients were studied with age average of 41.6 years and a male/female ratio of 2.1/1. The urinary pH mean decreased 0.23 sextile units from less to heavier body weight (p= 0.00). The urinary pH mean was 5.69 in malnourished and normal weight patients, it was 5.59 in overweight patients, and 5.53 in those obese (p= 0.00). CONCLUSION: fasting urinary pH is inversely related to body weight and body mass index in adult patients with urinary lithiasis without infection of the urinary tract.

Niveles séricos de magnesio en pacientes oncológicos tratados con nimotuzumab / Serum magnesium levels in oncologic patients treated with nimotuzumab

INTRODUCCIÓN: con el empleo de anticuerpos monoclonales anti-receptor del factor de crecimiento epidérmico (EGFR), se reportan efectos adversos, entre ellos hipomagnesemia e hipocalcemia. El nimotuzumab, anti-EGFR de producción nacional, tiene otras particularidades en su mecanismo de acción. OBJETIVO: analizar si la administración de este fármaco causa hipomagnesemia e hipocalcemia secundaria, como el resto de los anti-EGFR. MÉTODOS: los pacientes del estudio provienen del ensayo clínico controlado: Uso del anticuerpo monoclonal nimotuzumab en el tratamiento de pacientes con carcinoma de células escamosas de cabeza y cuello, en estadios avanzados. De cada uno de los dos grupos de tratamiento del ensayo fueron seleccionados, mediante muestreo simple aleatorio, 12 pacientes. Se registraron las variables demográficas y antropométricas; se realizaron las determinaciones de calcio y magnesio, utilizando muestras de suero obtenidas durante el ensayo clínico y conservadas a ­86 °C. La información fue procesada automatizada; paquete estadístico SPSS 15.0. Para determinar cambios en las concentraciones de Ca y Mg se utilizaron, respectivamente, los test de Friedman y de rangos con signos de Wilcoxon. En la comparación entre grupos se empleó el test de Wilcoxon-Mann-Whitney. RESULTADOS: los dos grupos de sujetos mostraron características semejantes. En el grupo tratado con nimotuzumab, las medias de las concentraciones de Mg fueron de 2,06; 2,17 y 2,11 mg/dL, al inicio, a las 3 sem y al final del tratamiento (p= 0,72). No existieron diferencias al comparar los cambios en las concentraciones de Mg y Ca entre ambos grupos (p= 0,07 y p= 0,86). CONCLUSIÓN: no existen evidencias para plantear que el nimotuzumab produzca hipomagnesemia e hipocalcemia secundarias, en cursos de tratamiento de 200 mg semanales por 6 sem.

INTRODUCTION: some adverse effects have been reported with the use of monoclonal antibodies against Epidermal Growth Factor Receptor (EGFR), including hypomagnesaemia and hypocalcaemia. Nimotuzumab is a Cuban anti-EGFR antibody with a particular mechanism of action, so it is important to know if Nimotuzumab causes these adverse effects. OBJECTIVE: assess whether the administration of this drug causes hypomagnesemia and secondary hypocalcemia, like other anti-EGFR. METHODS: patients on this study came from the controlled clinical assay: Use of Monoclonal Antibody Nimotuzumab in Treatment of Patients with Squamous-Cell Carcinoma of the Head and Neck In Advance Stages. 12 patients were taken by simple random sampling from each group of treatment of clinical assay (total 24). Demographic and anthropometric variables were recorded and mensuration of calcium and magnesium were done from serum samples obtained during clinical assay and preserved at ­86 °C. Information was processed using statistical package SPSS 15.0. Friedman test and Wilcoxon test were used to assess changes in Ca and Mg concentrations. Wilcoxon-Mann-Whitney test was used to compare the groups. RESULTS: both groups of subjects had similar characteristics. In the group of patients treated with nimotuzumab, Magnesium concentrations mean were 2.06, 2.17 and 2.11 mg/dL, at the beginning, after three weeks and at the end of treatment, respectively (p=0.72). There were not differences in Mg and Ca concentration changes along the study between groups (p= 0.07 y p= 0.86). CONCLUSIONS: there are not evidences to establish that nimotuzumab causes hypomagnesaemia and secondary hypocalcaemia in treatment of 200 mg a week during six weeks.

Experiencia de 20 años en biopsia renal percutánea en adultos del Instituto de Nefrología / Twenty years of experience of the Nephrology Institute in performing percutaneous renal biopsy in adults

INTRODUCCIÓN: la biopsia renal percutánea constituye un elemento clave en el manejo de la enfermedad renal crónica, además de tener gran valor en la evaluación de la disfunción renal aguda y en el establecimiento de pronósticos. OBJETIVOS: conocer las indicaciones de la biopsia renal percutánea de riñones propios, en el Instituto de Nefrología entre 1988 y el 2007; las complicaciones relacionadas, los diagnósticos y su relación con la forma de presentación de la enfermedad renal a través de estudio descriptivo y transversal. MÉTODOS: los datos primarios para esta investigación fueron recolectados de la boleta de biopsia. Todas las biopsias renales durante los años de estudio fueron realizadas, siguiendo el protocolo del Departamento de Anatomía Patológica. La información fue procesada automatizada; paquete estadístico SPSS 22.0. Se utilizó análisis de distribución de frecuencias, promedio y desviación estándar en las variables cuantitativas y el test de independencia para identificar posibles relaciones entre variables. RESULTADOS: la edad media de los pacientes fue de 35,9 años. El 49,6 % eran hombres. Presentaron complicaciones 59 pacientes (3,9 %), fundamentalmente sangramientos. El síndrome nefrótico (47,0 %) y el síndrome nefrítico (11,2 %) fueron las indicaciones más comunes. Predominaron las enfermedades glomerulares (91,3 %) y dentro de estas las glomerulopatías primarias (75,3 %). Los diagnósticos más comunes fueron la glomeruloesclerosis segmentaria y focal (20,6 %) y la glomerulopatía proliferativa mesangial (16,8 %). CONCLUSIONES: la indicación más común de biopsia renal percutánea, es el síndrome nefrótico y la complicación más frecuente, el sangramiento. Los diagnósticos más usualmente realizados son: glomerulesclerosis segmentaria y focal, glomerulopatía proliferativa mesangial y nefritis lúpica.

INTRODUCTION: percutaneous renal biopsy is a key element in the management of the chronic kidney disease in addition to having great value in the evaluation of acute kidney dysfunction and in making prognoses. OBJECTIVE: to identify the indications for percutaneos renal biopsy of native kidney in the Nephrology Institute from 1988 to 2007; the related complications, the diagnoses and their relationship with the form of presentation of the renal disease through a descriptive cross-sectional study. METHODS: primary data for this research work were gathered from the biopsy form. All the renal biopsies performed during the study years followed the Pathological Anatomy Department protocol. The statistical package SPSS 22.0 was used for data processing. Frequency distribution analysis, averages and standard deviation were used in the quantitative variables whereas the independence test served to identify possible associations of variables. RESULTS: the average age of patients was 35.9 years. In the group, 49.6 % were men. Fifty nine patients presented (3.9 %) presented with complications, mainly bleeding. Nephrotic syndrome (47 %) and nephritic syndrome (11.2 %) were the most common indications for biopsy. Glomerular diseases (91.3 %) predominated and primary glomerulopathies prevailed among them (75.3 %). The most common diagnoses were focal and segmental glomerulosclerosis (20.6 %) and mesangial proliferative glomerulopathy (16.8 %). CONCLUSIONS: the most common indication of percutaneous renal biopsy is the nephrotic syndrome whereas the most frequent complication is bleeding. The usual diagnoses were focal and segmental glomerulosclerosis, mesangial proliferative glomerulopathy and lupus nephritis.

Estimación de la función renal mediante creatinina sérica y fórmulas predictivas en población litiásica cubana / Stimation of renal function from serum creatinine and predictive formulas in Cuban population with lithiasic

Introducción: la función renal puede ser estimada mediante la creatinina sérica o por fórmulas predictivas, de ahí que resulte importante evidenciar el valor de estos métodos. Objetivo: determinar la validez de la creatinina sérica y la fiabilidad de las fórmulas de estimación de la función renal en población litiásica cubana. Métodos: se realizó un estudio transversal. Se estudiaron 6 290 pacientes con litiasis urinarias que se realizaron estudio metabólico en el Instituto de Nefrología entre 2006 y 2011, 4 133 (65,7 por ciento) del sexo masculino y 2 157 (34,3 por ciento), del femenino. La información fue procesada utilizando el paquete estadístico SPSS 15.0. Para evaluar la capacidad diagnóstica de la creatinina sérica se emplearon curvas ROC y en el análisis de la fiabilidad de las fórmulas, diagramas de Bland y Altman. Resultados: las fórmulas con menor diferencia promedio con respecto al aclaramiento de creatinina fueron en la ERC (TFG ≤ 90 mL/min/1,73 m²): Cockcroft-Gault (3,81 mL/min/1,73 m²; DE 19,20 mL/min/1,73 m²), Salazar-Corcoran (-4,47 mL/min/1,73 m²; DE 18,40 mL/min/1,73 m²) y Levey (MDRD) (4,69 mL/min/1,73 m²; DE 13,75 mL/min/1,73 m²) y en IRC (TFG < 60 mL/min/1,73 m ²): Levey (MDRD) (1,39 mL/min/1,73 m²; DE 10,22 mL/min/1,73 m²), Jelliffe 1 973 (2,15 mL/min/1,73 m²; DE 10,87 mL/min/1,73 m²) y Salazar-Corcoran (-4,47 mL/min/1,73 m²; DE 18,40 mL/min/1,73 m²). La ecuación de Baracskay tuvo la mayor diferencia promedio (-9,67 mL/min/1,73m²; DE 17,04 mL/min/1,73 m²). El valor óptimo de corte para la creatinina sérica en ERC fue 1,07 mg/dLy 0,89 mg/dL, en hombres y mujeres, respectivamente. Conclusiones: los resultados de este estudio sugieren que la fiabilidad de las fórmulas predictivas es alta, con excepción de la de Baracskay, utilizada en ancianos...

Introduction: renal function may be estimated from serum creatinine or with prediction formulas. Hence the importance of being aware of the usefulness of these methods. Objective: determine the validity of serum creatinine and the reliability of renal function estimation formulas. Methods: a cross-sectional study was conducted of 6 290 patients with urolithiasis (4 133 male and 2 157 female -65.7% and 34.3 percent, respectively-) undergoing metabolic studies at the Institute of Nephrology from 2006 to 2011. Data were processed with the statistical software SPSS version 15.0. ROC curves were used to evaluate the diagnostic capacity of serum creatinine. Reliability of the formulas was assessed with Bland-Altman plots. Results: the formulas with the smallest mean difference with respect to creatinine clearance were the following: for ERC (GFR ≤ 90 mL/min/1.73 m²): Cockcroft-Gault (3.81 mL/min/1.73 m²; DE 19.20 mL/min/1.73 m²), Salazar-Corcoran (-4.47 mL/min/1.73 m²; DE 18.40 mL/min/1.73 m²) and Levey (MDRD) (4.69 mL/min/1.73 m²; DE 13.75 mL/min/1.73 m²) and for IRC (GFR < 60 mL/min/1.73 m ²): Levey (MDRD) (1.39 mL/min/1.73 m²; DE 10.22 mL/min/1.73 m²), Jelliffe 1 973 (2.15 mL/min/1.73 m²; DE 10.87 mL/min/1.73 m²) and Salazar-Corcoran (-4.47 mL/min/1.73 m²; DE 18.40 mL/min/1.73 m²). The Baracskay formula showed the greatest mean difference (-9.67 mL/min/1.73m²; DE 17.04 mL/min/1.73 m²). Optimal cutoff value for serum creatinine in ERC was 1.07 mg/dL and 0.89 mg/dL for men and women, respectively. Conclusions: results suggest that the reliability of prediction formulas is high, except for Baracskay's, which is used in elderly patients...

Enfermedad renal quística adquirida y su relación con variables clínicas, demográficas y antropométricas en pacientes dialíticos / Acquired renal cystic disease and its relationship to clinical, demographic and anthropometric variables in patients on hemodialysis

Introducción: la enfermedad renal crónica (ERC) se asocia frecuentemente con enfermedad renal quística adquirida (ERQA). En el orden clínico, esta última suele ser asintomática, pero puede complicarse con carcinoma renal. Objetivo: identificar la frecuencia de presentación de ERQA y la posible relación de la longitud renal, el número y tamaño de los quistes, con características de pacientes en hemodiálisis. Métodos: se realizó un estudio analítico, transversal, en el cual se incluyó a todos los pacientes del Servicio de Hemodiálisis del Instituto de Nefrología, en tratamiento en junio de 2012. Fueron excluidos los que tenían enfermedad quística como causa de ERC, los nefrectomizados y aquellos con mala ventana ecográfica. La ecografía renal se realizó con equipo Toshiba Nemio XG de alta resolución y transductor convexo de 3,5 MHz. La información fue procesada de forma automatizada mediante el paquete estadístico SPSS, versión 15.0. Para identificar las posibles relaciones entre las variables fueron utilizados los test de Wilcoxon-Mann-Whitney y de Kruskal-Wallis. También se empleó el coeficiente de correlación lineal de Pearson (r). Resultados: el 38,4 por ciento de los pacientes presentó ERQA. Se encontró asociación del número de quistes con el tiempo en hemodiálisis, la dosis de eritropoyetina utilizada y las cifras de hemoglobina (p< 0,05 en los 3 casos). Entre tiempo en hemodiálisis y número de quistes, la relación fue directa y moderada (r= 0,60). Conclusiones: la frecuencia de ERQA es elevada en pacientes en hemodiálisis. El número de quistes aumenta con el tiempo en tratamiento y los pacientes con mayor número de quistes poseen valores más elevados de hemoglobina y requieren de dosis más bajas de eritropoyetina...

Introduction: chronic kidney disease (CKD) is frequently associated with acquired renal cystic disease (ARCD). The latter condition is usually clinically asymptomatic, but it may complicate with renal carcinoma. Objective: identify the frequency of presentation of ARCD and the possible relationship of renal length and the number and size of cysts, to characteristics of patients on hemodialysis. Methods: an analytical cross-sectional study was conducted of all the patients on hemodialysis at the Institute of Nephrology in June 2012. Patients with cystic disease as the cause of CKD, nephrectomized patients and those with a poor echographic window were not included. Renal echography was performed with high resolution Toshiba Nemio XG equipment and a 3.5 MHz convex transducer. Data was processed with the statistical software SPSS version 15.0. The Wilcoxon-Mann-Whitney and Kruskal-Wallis tests were used for identification of the possible relationships between variables. The Pearson linear correlation coefficient (r) was also used. Results: 38.4 percent of the patients had ARCD. An association was found between the number of cysts and the time on hemodialysis, the doses of erythropoietin used, and hemoglobin values (p< 0.05 in the three cases). The relationship between time on hemodialysis and number of cysts was direct and moderate (r= 0.60). Conclusions: the frequency of ARCD was high among patients on hemodialysis. The number of cysts increased with treatment time. Patients with a greater number of cysts have higher hemoglobin values and require smaller doses of erythropoietin...

Ingestión de sodio en pacientes litiásicos y su relación con variables demográficas y nutricionales / Sodium intake in lithiasic patients and its relationship to demographic and nutritional variables

Introducción: la medición de la excreción urinaria de sodio es importante en pacientes con litiasis urinaria, pues su excreción elevada predispone a hipercalciuria, el trastorno metabólico urinario más frecuente. Objetivo: determinar la ingestión (igual a excreción) de sodio e identificar su posible relación con variables demográficas y nutricionales, en pacientes con litiasis urinaria. Métodos: se desarrolló un estudio analítico, transversal, de los pacientes con litiasis urinaria que se hicieron estudio metabólico renal en el Instituto de Nefrología, entre enero 2011 y diciembre 2012. Se excluyeron los pacientes con factores que modifican la excreción de sodio. Las determinaciones de creatinina fueron realizadas por el método cinético de Jaffé, con espectrofotómetro Jenway®; las mediciones del sodio urinario, con analizador electrolítico marca Roche®. La información fue procesada de forma automatizada (SPSS versión 15.0). En cada categoría de las variables fueron calculadas media y desviación estándar de la excreción de sodio (mEq/d). Las comparaciones de los promedios se realizaron mediante la prueba t o mediante ANOVA. Resultados: de 1 985 pacientes estudiados, 1 363 fueron del sexo masculino (68,7 por ciento) y 622, del femenino (31,3 por ciento). La excreción urinaria media de sodio fue 235,29 mEq/d, globalmente, y resultó mayor en los hombres (252,69 mEq/d), al ser comparada con la de las mujeres (197,14 mEq/d) (p= 0,00). También se encontraron diferencias al comparar la excreción de sodio entre las categorías de valoración nutricional (p= 0,00) y de excreción de creatinina (p= 0,0). Conclusiones: la excreción urinaria de sodio es elevada en pacientes urolitiásicos, mayor en los hombres y en los sujetos con sobrepeso y obesidad...

Introduction: measurement of urinary sodium excretion is important in patients with urolithiasis, for a high level of excretion leads to hypercalciuria, the most common urinary metabolic disorder. Objective: to determine sodium intake (equal to excretion) and identify its possible relationship to demographic and nutritional variables in patients with urinary lithiasis. Methods: an analytical cross-sectional study was conducted in patientes with urinary lithiasis undergoing metabolic renal study at the Institute of Nephrology from January 2011 to December 2012. Patients with factors modifying sodium excretion were excluded. Creatinine determinations were made with Jaffé's kinetic method using a Jenway™ spectrophotometer. Urinary sodium was measured with a Roche™ electrolytic analyzer. Data was processed with the statistical software SPSS version 15.0. Variables for each category were estimated as mean and standard deviation of sodium excretion (mEq/d). Comparisons of averages were made with the t test or ANOVA. Results: of the 1 985 patients studied, 1 363 were male (68.7 percent) and 622 were female (31.3 percent). Global mean sodium urinary excretion was 235.29 mEq/d, greater in men (252.69 mEq/d) than in women (197.14 mEq/d) (p= 0.00). Differences were also found when sodium excretion was compared by nutritional assessment (p= 0.00) and creatinine excretion (p= 0.0). Conclusions: urinary sodium excretion is high in patients with urolithiasis. Values are higher in men, and in overweight and obese individuals...