Chronic interstitial nephritis in agricultural communities: a worldwide epidemic with social, occupational and environmental determinants.

Increase in the prevalence of chronic kidney disease (CKD) is observed in Central America, Sri Lanka and other tropical countries. It is named chronic interstitial nephritis in agricultural communities (CINAC). CINAC is defined as a form of CKD that affects mainly young men, occasionally women. Its aetiology is not linked to diabetes, hypertension, glomerulopathies or other known causes. CINAC patients live and work in poor agricultural communities located in CINAC endemic areas with a hot tropical climate, and are exposed to toxic agrochemicals through work, by ingestion of contaminated food and water, or by inhalation. The disease is characterized by low or absent proteinuria, small kidneys with irregular contours in CKD stages 3­4 presenting tubulo-interstitial lesions and glomerulosclerosis at renal biopsy. Although the aetiology of CINAC is unclear, it appears to be multifactorial. Two hypotheses emphasizing different primary triggers have been proposed: one related to toxic exposures in the agricultural communities, the other related to heat stress with repeated episodes of dehydration heath stress and dehydration. Existing evidence supports occupational and environmental toxins as the primary trigger. The heat stress and dehydration hypothesis, however, cannot explain: why the incidence of CINAC went up along with increasing mechanization of paddy farming in the 1990s; the non-existence of CINAC in hotter northern Sri Lanka, Cuba and Myanmar where agrochemicals are sparsely used; the mosaic geographical pattern in CINAC endemic areas; the presence of CINAC among women, children and adolescents who are not exposed to the harsh working conditions; and the observed extra renal manifestations of CINAC. This indicates that heat stress and dehydration may be a contributory or even a necessary risk factor, but which is not able to cause CINAC by itself.

Epidemiology of chronic kidney disease in adults of Salvadoran agricultural communities.

INTRODUCTION: In El Salvador, chronic kidney disease is a serious and growing public health problem. Chronic renal failure was the first cause of hospital deaths in men and the fifth in women in 2011. OBJECTIVE: Determine prevalence of CKD, CKD risk factors (traditional and nontraditional) and renal damage markers in the adult population of specific rural areas in El Salvador; measure population distribution of renal function; and identify associated risk factors in CKD patients detected. METHODS: A cross-sectional analytical epidemiological study was conducted based on active screening for chronic kidney disease and risk factors in persons aged ≥18 years during 2009-2011. Epidemiological and clinical data were gathered through personal history, as well as urinalysis for renal and vascular damage markers, determinations of serum creatinine and glucose, and estimation of glomerular filtration rates. Chronic kidney disease cases were confirmed at three months. Multiple logistical regression was used for statistical analysis. RESULTS: Prevalence of chronic kidney disease was 18% (23.9% for men and 13.9% for women) in 2388 persons: 976 men and 1412 women from 1306 families studied. Chronic kidney disease with neither diabetes nor hypertension nor proteinuria ≥1 g/L (51.9%) predominated. Prevalence of chronic renal failure was 11% (17.1% in men and 6.8% in women). Prevalence of renal damage markers was 12.5% (higher in men): microalbuminuria, 6.9%; proteinuria (0.3 g/L), 1.7%; proteinuria (1g/L), 0.6%; proteinuria (2 g/L), 0.4 %; and hematuria, 1.5%. Prevalence of chronic kidney disease risk factors was: diabetes mellitus, 9%; hypertension, 20.9%; family history of chronic kidney disease, 16.5%; family history of diabetes mellitus, 18.5%; family history of hypertension, 30.6%; obesity, 21%; central obesity, 24.9%; NSAID use, 84.2%; smoking, 9.9%; alcohol use, 15%; agricultural occupation, 31.2%; and contact with agrochemicals, 46.7%. Chronic kidney disease was significantly associated with male sex, older age, hypertension, agricultural occupation, family history of chronic kidney disease and contact with the agrochemical methyl parathion. CONCLUSIONS: The results of this study support suggestions from other research that we are facing a new form of kidney disease that could be called agricultural nephropathy.

Clinical characteristics of chronic kidney disease of nontraditional causes in Salvadoran farming communities.

INTRODUCTION: Chronic kidney disease is a serious health problem in El Salvador. Since the 1990s, there has been an increase in cases unassociated with traditional risk factors. It is the second leading cause of death in men aged >18 years. In 2009, it was the first cause of in-hospital death for men and the fifth for women. The disease has not been thoroughly studied. OBJECTIVE: Characterize clinical manifestations (including extrarenal) and pathophysiology of chronic kidney disease of nontraditional causes in Salvadoran farming communities. METHODS: A descriptive clinical study was carried out in 46 participants (36 men, 10 women), identified through chronic kidney disease population screening of 5018 persons. Inclusion criteria were age 18-59 years; chronic kidney disease at stages 2, 3a and 3b, or at 3a and 3b with diabetes or hypertension and without proteinuria; normal fundoscopic exam; no structural abnormalities on renal ultrasound; and HIV-negative. Examinations included social determinants; psychological assessment; clinical exam of organs and systems; hematological and biochemical parameters in blood and urine; urine sediment analysis; markers of renal damage; glomerular and tubular function; and liver, pancreas and lung functions. Renal, prostate and gynecological ultrasound; and Doppler echocardiography and peripheral vascular and renal Doppler ultrasound were performed. RESULTS: Patient distribution by chronic kidney disease stages: 2 (32.6%), 3a (23.9%), 3b (43.5%). Poverty was the leading social determinant observed. Risk factor prevalence: agrochemical exposure (95.7%), agricultural work (78.3%), male sex (78.3%), profuse sweating during work (76.3%), malaria (43.5%), NSAID use (41.3%), hypertension (36.9%), diabetes (4.3%). General symptoms: arthralgia (54.3%), asthenia (52.2%), cramps (45.7%), fainting (30.4). Renal symptoms: nycturia (65.2%), dysuria (39.1%), foamy urine (63%). Markers of renal damage: macroalbuminuria (80.4%), ß2 microglobulin (78.2%), NGAL (26.1%). Renal function: hypermagnesuria (100%), hyperphosphaturia (50%), hypernatriuria (45.7%), hyperkaluria (23.9%), hypercalciuria (17.4%), electrolyte polyuria (43.5%), metabolic alkalosis (45.7%), hyponatremia (47.8%), hypocalcemia (39.1%), hypokalemia (30.4%), hypomagnesemia (19.6%). Imaging: Ultrasound showed fatty liver (93.5%) and vascular Doppler showed tibial artery damage (66.7%). Neurological symptoms: abnormal tendon reflexes (45.6%), Babinski sign and myoclonus (6.5%), sensorineural hearing loss (56.5%). CONCLUSIONS: This chronic kidney disease studied behaves clinically like chronic tubulointerstitial nephropathy, but with systemic manifestations not attributable to kidney disease. While male agricultural workers predominated, women and adolescents were also affected. Findings support a hypothesis of multifactorial etiology with a key role played by nephrotoxic environmental agents.

Histopathology of chronic kidney disease of unknown etiology in Salvadoran agricultural communities.

INTRODUCTION: For at least a decade, a chronic kidney disease unassociated with diabetes mellitus, hypertension or any of the more common traditional causes, has been reported in Salvadoran agricultural communities. OBJECTIVE: Characterize histopathology of chronic kidney disease of unknown etiology in patients from Salvadoran agricultural communities, describe renal damage associated with each disease stage, and assess associations between histopathological alterations and sociodemographic variables. METHODS: The study involved 46 patients of both sexes, aged =18 years. After clinical, laboratory and imaging examinations, kidney biopsies were performed and renal tissue assessed for interstitial fibrosis, tubular atrophy, interstitial inflammatory infiltration, sclerosis, increase in glomerular size and extraglomerular vascular lesions (according to the Banff 97 classification used for kidney transplant rejection). Special staining was done: Schiff periodic acid, Masson trichrome and methenamine silver. Immunofluorescence techniques were used to evaluate IgA, IgG, IgM, complement C1q and C3, fibrin, and kappa and lambda light chain deposits. RESULTS: The main findings were interstitial fibrosis and tubular atrophy with or without inflammatory monocyte infiltration. In addition, generalized sclerosis, increased glomerular size, collapse of some glomerular tufts, and lesions of extraglomerular blood vessels (such as intimal proliferation and thickening and vacuolization of the tunica media) were observed. Interstitial fibrosis and glomerulosclerosis were associated with male sex. Sugarcane workers showed more interstitial fibrosis and tubular atrophy and less glomerulomegaly than other occupational groups. CONCLUSION: The morphological pattern in all biopsies was one of chronic tubulointerstitial nephropathy with secondary glomerular and vascular damage, in different stages of evolution of chronic kidney disease, independent of age, sex or occupation.

Chronic kidney disease of unknown etiology in agricultural communities.

In recent years, Central America, Egypt, India and Sri Lanka have reported a high prevalence of chronic kidney disease of unknown etiology in agricultural communities, predominantly among male farmworkers. This essay examines the disease's case definitions, epidemiology (disease burden, demographics, associated risk factors) and causal hypotheses, by reviewing published findings from El Salvador, Nicaragua, Costa Rica, Sri Lanka, Egypt and India. The range of confirmed chronic kidney disease prevalence was 17.9%-21.1%. Prevalence of reduced glomerular filtration (<60 mL/min/1.73 m2 body surface area) based on a single serum creatinine measurement was 0%-67% men and 0%-57% women. Prevalence was generally higher in male farmworkers aged 20-50 years, and varied by community economic activity and altitude. Cause was unknown in 57.4%-66.7% of patients. The dominant histopathological diagnosis was chronic tubulointerstitial nephritis. Associations were reported with agricultural work, agrochemical exposure, dehydration, hypertension, homemade alcohol use and family history of chronic kidney disease. There is no strong evidence for a single cause, and multiple environmental, occupational and social factors are probably involved. Further etiological research is needed, plus interventions to reduce preventable risk factors.

Latin American Dialysis and Transplant Registry: 2008 prevalence and incidence of end-stage renal disease and correlation with socioeconomic indexes.

In 2008, 563,294,000 people were living in Latin America (LA), of which 6.6% were older than 65. The region is going through a fast demographic and epidemiologic transition process, in the context of an improvement in socio-economic indices. The Latin American Dialysis and Renal Transplant Registry has collected data since 1991, through an annual survey completed by 20 affiliated National Societies. Renal replacement treatment (RRT) prevalence and incidence showed an increase year by year. The prevalence rate (in all modalities) correlated with the World Bank country classification by income and the epidemiologic transition stage the countries were experiencing. RRT prevalence and kidney transplantation rates correlated significantly with gross national income (GNI), health expenditure in constant dollars (HeExp), % older than 65, life expectancy at birth, and % of the population living in urban settings. Kidney transplantation increased also, year by year, with more than 50% of transplants performed using kidneys from deceased donors. Double transplants were performed in six countries. RRT prevalence and incidence increased in LA, and are associated with indexes reflecting higher and more evenly distributed national wealth (GNI and HeExp), and the stage of demographic and epidemiological transition.

Chronic kidney disease and associated risk factors in the Bajo Lempa region of El Salvador: Nefrolempa study, 2009.

INTRODUCTION: In El Salvador, end-stage renal disease is the leading cause of hospital deaths in adults, the second cause of death in men and the fifth leading cause of death in adults of both sexes in the general population. OBJECTIVE: Identify risk factors for chronic kidney disease and urinary markers of renal and vascular damage, measure kidney function and characterize prevalence of chronic kidney disease in persons aged ≥18 years in the Bajo Lempa region of El Salvador. METHODS: A cross-sectional analytical epidemiological study was carried out using active screening for chronic kidney disease and associated risk factors in individuals aged ≥18 years in the Bajo Lempa Region, a rural, coastal area in El Salvador. Door-to-door visits and clinical examinations were conducted. Epidemiological and clinical data were collected including: family and personal clinical history of disease; biological, behavioral, social and environmental risk factors; physical measurements; urinalysis for markers of renal and vascular damage; and blood tests (serum creatinine, serum glucose, lipid profile). Glomerular filtration rate was calculated using the Modification of Diet in Renal Disease formula. Chronic kidney disease case confirmation was done three months later. Multiple logistic regression was used for data analysis. RESULTS: A total of 375 families and 775 individuals (343 men, 432 women) were studied-88.3% of the total resident population in the region. Elevated prevalence of risk factors was observed: diabetes mellitus, 10.3%; hypertension,16.9%; family history of chronic kidney disease, 21.6%; dyslipidemias, 63.1%; overweight, 34%; obesity, 22.4%; metabolic syndrome, 28.8%; use of non-steroidal anti-inflammatory drugs, 74.8%; infectious diseases, 86.9%; agricultural occupation, 40.6% (80.6% in men); and contact with agrochemicals, 50.3% (82.5% in men). Prevalence renal damage markers was 15.8% (greater in men): microalbuminuria 6.3%; proteinuria 5.7%; hematuria 3.5%; proteinuria-hematuria 0.3%. Proteinuria of <1 g/L predominated. Prevalence of chronic kidney disease was 17.9% (25.7% in men; 11.8% in women). Distribution by stages: stage 1, 4.6%; stage 2, 3.5%; stage 3, 6.2%; stage 4, 3.0%; stage 5, 0.6%. In patients with chronic kidney disease, most common was non-diabetic chronic kidney disease (86.3%), followed by chronic kidney disease associated with neither diabetes nor hypertension (54.7%). Prevalence of chronic renal failure was 9.8% (17% in men; 4.1% in women). Multiple logistic regression showed significant association with increasing age, male sex, hypertension and family history of chronic kidney disease. CONCLUSIONS: Elevated prevalence of chronic kidney disease, chronic renal failure and risk factors was found, compared to international reports. Most common was chronic kidney disease of unknown cause, associated with neither diabetes nor hypertension. Associations were found with age, male sex, hypertension and family history of chronic kidney disease, with decline in kidney function beginning at early ages. Male farmers have a dual burden of non traditional (occupational, toxic environmental) and traditional (vascular) risk factors that could act in synergy, contributing to kidney damage.

INTRODUCCIÓN En El Salvador, la enfermedad renal crónica terminal es la causa principal de muerte hospitalaria en adultos, la segunda causa de muerte en los hombres y la quinta causa principal de muerte entre adultos de ambos sexos en la población general. OBJETIVO Identificar los factores de riesgo de la enfermedad renal crónica y los marcadores de daño renovascular en orina, medir la función renal y caracterizar la prevalencia de enfermedad renal crónica en personas X18 años de edad en la región del Bajo Lempa en El Salvador. METODOS Se realizó un estudio epidemiológico transversal y analítico de la enfermedad renal crónica y los factores de riesgo asociados en individuos con edades X18 años por medio de pesquisa activa en la Región del Bajo Lempa, una zona costera rural en El Salvador. Se efectuaron visitas casa por casa y consultas médicas. Se recolectaron datos epidemiológicos y clínicos que incluían: historia clínica personal y familiar para la enfermedad; factores de riesgo biológicos, de conducta, sociales y ambientales; mediciones físicas; análisis de orina buscando marcadores de daño renovascular y exámenes de sangre (creatinina y glucosa en suero, lipidograma). La tasa de filtración glomerular se calculó usando la fórmula de MDRD (sigla en inglés de Modificación de la Dieta en la Enfermedad Renal). La confirmación de casos de enfermedad renal crónica se realizó en un período de tres meses. Se utilizó la regresión logística múltiple para analizar los datos. RESULTADOS Se estudiaron un total de 375 familias y 775 individuos (343 hombres, 432 mujeres), el 88,3% del total de la población residente en la región. Se observó una elevada prevalencia de factores de riesgo: diabetes mellitus en 10,3%; hipertensión en 16,9%; antecedentes familiares de enfermedad renal crónica en 21,6%; dislipidemias en 63,1%; sobrepeso en 34%; obesidad en 22,4%; síndrome metabólico en 28,8%; uso de medicamentos anti-inZ amatorios no esteroideos en 74,8%, enfermedades infecciosas en 86,9%, 40,6 % eran agricultores (80,6% de los hombres) y 50,3% tenían contacto con agroquímicos (82,5% de los hombres). La prevalencia de marcadores de daño renal fue de 15,8% (mayor en los hombres): microalbuminuria de 6,3%; proteinuria de 5,7%; hematuria de 3,5%; proteinuria-hematuria de 0,3%. Predominó la proteinuria <1 g/L. La prevalencia de enfermedad renal crónica fue de 17,9% (25,7 en los hombres; 11,8% en las mujeres). La distribución por estadios fue la siguiente: estadio 1, un 4,6%; estadio 2, un 3,5%' estadio 3, un 6,2%; estadio 4, un 3,0% y en estadio 5, un 0,6%. En pacientes con enfermedad renal crónica, la más común fue la enfermedad renal crónica no diabética (86,3%), seguida de la enfermedad renal crónica no asociada a diabetes ni a hipertensión (54,7%). La prevalencia de la insuficiencia renal crónica fue de 9,8% (17% en los hombres y 4,1% en mujeres). La regresión logística múltiple mostro una asociación significativa con el aumento de la edad, sexo masculino, hipertensión y antecedentes familiares de enfermedad renal crónica. CONCLUSIONES Se halló una elevada prevalencia de enfermedad renal crónica, insuficiencia renal crónica y factores de riesgo en comparación con lo reportado internacionalmente. La más frecuente fue la enfermedad renal crónica de causa desconocida, no asociada con diabetes ni hipertensión. Se encontraron asociaciones con la edad, sexo masculino, hipertensión e historia familiar de enfermedad renal crónica, con una disminución de la función renal que comienza a edades tempranas. Los agricultores hombres tienen la doble carga de riesgos no tradicionales (ocupacionales, toxico-ambientales) y tradicionales (vasculares) que podrían actuar de manera sinérgica, contribuyendo al daño renal. PALABRAS CLAVE Enfermedad renal crónica/epidemiologia, factores de riesgo, prevalencia, salud ocupacional, salud ambiental, plaguicidas, agroquímicos, El Salvador

Albuminuria as a marker of kidney and cardio-cerebral vascular damage. Isle of Youth Study (ISYS), Cuba.

INTRODUCTION: The disease complex comprised of atherosclerosis, chronic kidney disease (CKD) and other associated chronic vascular diseases is the leading cause of mortality worldwide. Microalbuminuria is a marker for vascular damage in the heart, kidney and brain. This paper presents selected findings of the clinical-epidemiological Isle of Youth Study (ISYS) of markers for kidney and vascular damage from chronic vascular diseases and their common risk factors in total population, focusing on Phase 2 reassessment (in 2010) of Phase 1 (2004 to 2006) results. OBJECTIVES: (1) Update the prevalence of risk factors in the study population aged ≥20 years (adult population). (2) Confirm presence of microalbuminuria in at-risk adults diagnosed as presumptive positives in Phase I. (3) Evaluate association between microalbuminuria and selected risk factors. METHODS: Of 3779 adults positive for microalbuminuria in ISYS Phase 1, 73.1% were reevaluated. The risk-factor questionnaire was re-administered and blood pressure, weight and height were measured. Blood was tested for creatinine, glycemia, cholesterol and triglycerides. Glomerular filtration rate was calculated using the Modification of Diet in Renal Disease (MDRD) formula. Albuminuria was measured in urine using Micral-Test (Germany) and albumin/creatinine ratio (ACR) by nephelometry. This paper uses ACR as the reference for analyzing risk factor associations. Double-entry tables were developed to analyze association among microalbuminuria, risk factors and co-morbidities. RESULTS: Most prevalent risks were hypertension, consumption of nonsteroidal anti-inflammatory drugs (NSAIDs), excess weight and hypertriglyceridemia. Microalbuminuria was confirmed in 18% of cases, using the same test. Elevated prevalence of microalbuminuria was positively associated with advancing age, male sex, underweight, smoking, NSAID use, dyslipidemia, hypertension, diabetes, heart disease and stroke. CONCLUSIONS: The at-risk cohort studied presented low levels of confirmation for positive microalbuminuria. Positive microalbuminuria stratified individuals at greatest risk, except for obesity.

Prevalence of Obesity and its Association with Chronic Kidney Disease, Hypertension and Diabetes Mellitus. Isle of Youth Study (ISYS), Cuba.

Introduction: Obesity is a social disease constituting a global pandemic. It is present in 90% of diabetic and 65% of hypertensive patients. It is associated with cardiometabolic syndrome and with damaging physiopathological mechanisms, particularly for the vascular system and the kidneys. On Cuba's Isle of Youth, a community-based epidemiological study of chronic kidney disease (CKD), hypertension (HTN), diabetes mellitus (DM) and cardio-cerebral vascular disease was carried out in total population, including an examination of common risk factors. Objective: Based on the Isle of Youth Study (ISYS) data, determine prevalence of obesity and overweight, and their association with CKD, HTN, DM, and shared risk factors for all these conditions in total population of the Isle of Youth, Cuba. Methods: Phase 1: Population diagnosis (November 2004-April 2006): 96.6% of the Isle of Youth's total population (80,117) was studied, including all ages and both sexes. Information was offered to the public, and written informed consent obtained. Screening was conducted by participant questionnaire including risk factors, physical measurements (weight, height, blood pressure and body mass index), and a single first-morning urine sample to determine the presence of vascular-renal damage markers ­ proteinuria and hematuria (Combur 10 Test, Roche), and microalbuminuria (Micral Test, Roche). When results were positive, serum creatinine was determined and glomerular filtration rate (GFR) estimated with Modification of Diet in Renal Disease (MDRD) formula for adults and Schwartz formula for children <15 years. Data obtained were analyzed to determine association of participants' nutritional status with prevalence of chronic kidney disease, hypertension and diabetes mellitus, as well as a set of common risk factors. Results: Population <20 years: Obesity prevalence 3.2%; positive urine markers in 56.9% of obese and 8.9% of non-obese participants; positive albuminuria in 38% of obese and 3% of non-obese. Obese participants were found to be hyperfiltrating. DM prevalence was 9.5% in obese and 1.1% in non-obese participants. Population ≥20 years: Overweight, 31.3%; obese, 13.4%. Positive markers in normal-weight, overweight and obese individuals were 18.3%, 21.2% and 32.7%, respectively; microalbuminuria values increased with weight. Obese individuals were found to be hyperfiltrating. HTN prevalence in normal-weight, overweight and obese individuals was 18.3%, 31.5%, and 51.0% respectively; DM rates were 2.8%, 5.2% y 11.3%, respectively. Conclusion: In Cuba, obesity poses significant risk for vascular and renal damage and should be the focus of increased prevention efforts.

Design & Methodology of the Isle of Youth Community-Based Epidemiological Study of CKD, Cardio-cerebral Vascular Disease, Hypertension, and Diabetes Mellitus (ISYS).

UNLABELLED: The methodology is described in detail for the population-based Isle of Youth Study (ISYS) for epidemiological evaluation of CKD associated with cardio-cerebral vascular disease, arterial hypertension, diabetes mellitus, and other risk factors. BACKGROUND: Chronic kidney disease emerges as an important and growing global health problem associated with an increase in the incidence and prevalence of the above mentioned diseases. ISYS Objectives: Ascertain CKD morbidity and its relation to chronic vascular diseases and other risk factors in whole population of Cuba's Isle of Youth special municipality. METHOD: 96.6% of the Isle of Youth's total population (80,117 inhabitants) was studied, all ages and both sexes, November 15, 2004-April 30, 2006. The public was offered general information on the objectives and benefits of the study, and participants provided informed consent. Active screening was performed via personal interview questionnaire and urine sample to determine markers of kidney damage: proteinuria and hematuria (Combur-10-Test) and microalbuminuria (Micral-Test), according to a diagnostic algorithm. For those testing positive for any marker, serum creatinine was studied and glomerular filtration rate (GFR) calculated - in adults by Cockcroft-Gault and Modification of Diet in Renal Disease (MDRD) formulas and in children aged <15 years, by Schwartz - to stratify CKD by stages. Blood pressure, height, weight, and body mass index (BMI) were determined. EXPECTED RESULTS: Prevalence of kidney damage markers in general population and risk groups; relationship in population between CKD and cardio-cerebral vascular disease, diabetes mellitus, hypertension, and other risk factors; comparison of Cockcroft-Gault and Modification of Diet in Renal Disease (MDRD) formulas for measuring the GFR and their application to studies involving mass population screenings; and stratification of CKD in population. CONCLUSIONS: ISYS Phase I, active screening of markers for renal damage was concluded using the methodology described above; results are pending publication. (Abstract) Erratum Almaguer López M, Herrera Valdés R, Chipi Cabrera J, Toirac Cabrera X, Castellanos Rabanal O, Bacallao Gallestey J. Design & methodology of the Isle of Youth community-based epidemiological study of CKD, cardio-cerebral vascular disease, hypertension, and diabetes mellitus (ISYS). MEDICC Review. 2007;9(1):23-9. The correct formula for MDRD appearing on page 27 is: MDRD GFR = 186.3 x serum creatinine (mg/dL)-1.154 x age-0.203 x 0.742 for females x 1.21 if the person is black.

Chronic kidney disease in Cuba: epidemiological studies, integral medical care, and strategies for prevention.

The experience of the Republic of Cuba regarding epidemiological studies, integral medical care, and strategies for the prevention of chronic kidney disease is summarized in this report. Cuba has a National Program for Chronic Renal Disease, Dialysis, and Renal Transplantation. There is a national nephrology net, integrated by the Institute of Nephrology as the coordinator center, that has 47 nephrology services with a hemodialysis unit (24 of them with peritoneal dialysis unit), 9 transplantation centers, 33 organ procurement hospitals, and 5 histocompatibility laboratories. In 2004, the incidence rate in dialysis patients was 111 pmp, and the prevalence rate was 149 pmp, demonstrating an increasing mean of 17.0% and 10.0% per year, respectively. Renal transplantation rate was 16.6 pmp. The detection, registration, and follow-up of patients with chronic kidney disease (serum creatinine > or =1.5 mg/dL or glomerular filtration rate <60 mL/min) by family doctors was 9,761 patients, 0.87 patients per 1,000 inhabitants. In the 1980s, three population-based screening studies were performed to define the burden of chronic renal failure in different regions of Cuba. The prevalence rate was 1.1, 3.3, and 3.5 per 1,000 inhabitants, respectively. At present, another three population-based screening studies are ongoing in order to detect the chronic kidney disease in earliest stages. The continuing medical education activities have been very useful in raising the awareness of medical doctors and the basic health staff about the threats posed by and the strategies to prevent, diagnose, and treat chronic kidney disease.

Red de Información en nefrologia: visión del usuario / Net of Information in nefrologia: the user's vision

Se presenta la planificación estratégica y los resultados alcanzados por la Red Informática de Nefrología Cubana, cuyo núcleo radica en el Instituto Nacional de Nefrología Dr Abelardo Buch López, rector, cuna y escuela de la especialidad. Basado en el apoyo del Estado cubano y la cooperación internacional, se logra el financiamiento para un proyecto de informatización de la red nacional de Nefrología en tres vertientes: 1- Creación de una moderna red local hospitalaria; 2- Unión de los 47 Servicios de Nefrología del país con la oficina de Coordinación del programa de Nefrología, en un portal único con interconexión permanente para responder a los requerimientos del sistema; 3- Laboratorio Epidemiológico Renal de la Isla de la Juventud para el estudio de la enfermedad vascular. Los progresos obtenidos en su perfeccionamiento y desarrollo muestran cómo se puede materializar la aspiración de lograr en este 2006 la informatización total de la Nefrología cubana en sus diferentes vertientes: estadísticas de dirección, epidemiología, registro de enfermos renales e historia clínica computarizada, diálisis y trasplante, operativos de trasplante y selección de la pareja donante-receptor,teleconferencias, servicios de segunda opinión y control de la calidad(AU)

Primary health care strategies for the prevention of end-stage renal disease in Cuba.

End-stage renal disease (ESRD) is a major health problem in the world, including Cuba. There is an increasing trend in both the incidence and prevalence of ESRD. Global projections consistently show an increase of patients in maintenance dialysis, and also an epidemic trend in diabetes mellitus and hypertension, two diseases that are leading causes of ESRD in most countries. A new paradigm is necessary to handle this major health problem, such as a public health model that integrates health promotion and disease prevention. In 1996, the Ministry of Public Health of Cuba launched a national program for the prevention of chronic renal failure (CRF). The progressive implementation of this program follows several steps: the analysis of the resources and health situation in the country; epidemiological research to define the burden of CRF; continuing education for nephrologists, family doctors, and other health professionals; and reorientation of primary health care toward increased nephrology services, intervention, and surveillance. The main outcomes of the program have been: a rational redistribution of nephrology services in corresponding health areas of primary health care; nephrologists being brought closer to the community; an improvement in the knowledge and ability of family doctors and nephrologists in the prevention of chronic renal disease; an increase in the number of patients with CRF (serum creatinine > or = 133 micromol/L or > or = 1.5 mg/dL, or a glomerular filtration rate < 60 mL/min) who are registered in primary health care every year, from a prevalence of 0.59 per 1,000 inhabitants at the beginning of the program in 1996 to 0.92 per 1,000 inhabitants in 2002, with a mean prevalence growth of 9.2% per year; a significant reduction (0.1%) in the incidence of viral hepatitis B in dialysis patients after the implementation of vaccination against viral hepatitis B in CRF patients who are registered in primary health care; and the implementation of CRF surveillance in primary health care, which provides periodic information on CRF burden, patterns, and trends to assist evidence-based public-health decision making, and measures the impact of interventions in the population. Primary health care is an essential tool, and the community is an appropriate social space for health promotion and the prevention of CRF and ESRD.

Hepatitis C virus antibodies and other markers of blood-transfusion-transmitted infection in multi-transfused Cuban patients.

BACKGROUND: HCV was initially identified in 1989 when it was found to be the primary causative agent of non-A, non-B hepatitis,a condition associated with high rates of progressive and end-stage liver disease, cirrhosis, and hepatocellular carcinoma. Since then, appreciation of the significant worldwide health impact of HCV infection has grown. HCV infection was identified as a public health problem in Cuba in the 1990s. Despite universal blood donor screening, which was achieved in 1995 using the Cuban immunoassay system UMELISA HCV, the infection is still found in multi-transfused patients. OBJECTIVES: To determine the magnitude of HCV, HBV and HIV-1&2 infections among Cuban blood recipients and to assess the role of potential risk factors. STUDY DESIGN: Cross-sectional study of 318 patients from Havana City, Pinar del Río and Villa Clara, who had been previously treated with 10 or more units of allogenic blood or blood components in at least two different occasions. The patients were evaluated for HCV Ab, HBsAg, anti-HBc Ab, and HIV-1&2 Ab. Data management and statistical analysis were performed using EpiInfo and SSPS software. RESULTS: Prevalence rates were 51.6% for HCV Ab; 5.3% for HBsAg; 45.0% for anti-HBc and 0% for HIV-1&2 Ab. Ten (3.1%) patients were co-infected with HCV and HBV Blood transfusion was not identified as the main risk factor for HCV transmission. The number of blood units received by the patients was not statistically associated with the HCV Ab prevalence. CONCLUSIONS: Infection with HCV was identified more frequently than HBV and HIV among our study population. Patients undergoing hemodialysis were at the highest risk of becoming infected. Medical procedures including surgery, transplantation, invasive odontology, and sharing or reuse of needles and syringes, are associated with higher HCV Ab seroprevalences compared with blood transfusion alone.

Antígeno HLA B-27 como marcador genético en la espondilitis anguilosante. Estudio de 40 casos / HLA B27 antigen as a genetic marker for ankylosing spondylitis. Study of 40 cases

El ejemplo más evidente de asociación de un antígeno del sistema HLA y una enfermedad, es el del antígeno B-27 y la espondilitis anquilosante. El grado de esta asociación varía en las diferentes poblaciones. Son estudiados 40 casos de pacientes con esta afección residentes en Ciudad de La Habana y comparadas las frecuencias fenotípicas del sistema HLA encontradas, con las de 109 individuos normales considerados como representativos de la población cubana en su conjunto. En los enfermos el antígeno HLA B-27 estuvo presente en el 55 porciento de los casos, mientras que sólo se encontró en el 5 porciento de la población normal. La diferencia es estadísticamente significativa(AU)

HLA y asma / HLA and asthma

Se estudiaron 90 asmáticos provenientes de los servicios de alergología de los hospitales docentes, "Enrique Cabrera" y "William Soler" de Ciudad de la Habana. El grupo control estuvo constituido por 109 personas normales estudiadas durante el Taller Internacional de Histocompatibilidad celebradoen la Habana en mayo de 1974. Para clasificar el tipo hístico se utilizaron 118 antisueros que definían la presencia de 26 antígenos HLA. Se utilizó la técnica de linfocitoxicidad NIH estandarizada. El análisis estadístico se realizó por elestadígrafo X² en la corrección de Yates. Al comparar la frecuencia fenotípica de los antígenos HLA de los loci A y B se encontró aumento estadísticamente significativo del antígeno HLA-A9 en los asmáticos, en relación con el grupo control(AU)

Glomerulonefritis rápidamente progresiva ( No estreptocócica ): estudio de 9 casos / Progressive glomerulonephritis ( non-streptococcal): a nine-case study

Se informa que en un período de 5 años, entre diciembre de 1967 y diciembre de 1972, ingresaron en el instituto de Nefrología, 9 casos de glomerulonefritis rápidamente progresiva ( no estreptocócica ), los cuales fueron analizados en los aspectos fundamentales de su comportamiento clínico y humoral. Se realizó una valoración semicuantitativa de las lesiones histológicas observadas en la muestra de tejido renal, obtenidas por punción percutánea, nefrectomía o necropsia. Se analizaron los resultados de la terapéutica con drogas inmunosupresoras y anticoagulantes en 2 casos, y los del transplante renal realizados en 3(AU)