Trastornos glomerulares en la práctica médica / Glomerulopathies in the medical practice

RESUMEN Las glomerulopatías agrupan varias nefropatías con lesiones fundamentalmente del corpúsculo renal y que se expresan principalmente por proteinuria, hematuria, edemas e hipertensión arterial. La presentación clínica varía en dependencia del tipo de enfermedad de que se trate. Constituye la causa más frecuente de enfermedad renal crónica en adultos jóvenes, por lo que su estudio resulta imprescindible sobre todo para el nivel primario de salud. El propósito fue actualizar consideraciones pertinentes sobre la conducta diagnóstica y terapéutica integral ante una glomerulopatía y valorar emisión de recomendaciones al respecto. Se realizó una búsqueda, análisis y síntesis de información a través de Bases de datos ScieLO Cuba, ScieLO regional, Pubmed, Cumed, Clinical Key en el período 2012-2017 con las palabras clave: síndrome nefrótico, glomerulonefritis, diagnóstico, terapéutica, atención integral. El abordaje en las glomerulopatías es integral, multidisciplinario e individualizado. En Cuba constituyen la cuarta causa de enfermedad renal crónica y predomina el síndrome nefrítico agudo postinfeccioso. El método clínico juega en ello un papel trascendental a la hora de reconocer y registrar sus aspectos clínicos, su etiología, su fisiopatología, y los exámenes complementarios que confirman su presencia o sus complicaciones, así como un tratamiento oportuno que garanticen el perfeccionamiento asistencial. El arma más poderosa ante el reto de los trastornos glomerulares es la visión integradora y con enfoque individual y social protagonizado por el médico ante este grupo de nefropatías en adultos.

ABSTRACT Glomerulopathies encompass a group of several renal disorders with lesions, mainly in the renal corpuscle, expressed in proteinuria, hematuria, edemas and arterial hypertension. Their clinical manifestations change in dependence of the kind of disease. They are the most frequent cause of chronic renal disease in young adults; therefore their study is very important above all in the health care primary level. The aim was updating pertinent considerations on the diagnostic behavior and comprehensive therapy in the case of glomerulopathy, and evaluating the emission of recommendations regarding to them. A search, analysis and synthesis of information was carried out in the databases ScieLO Cuba, ScieLO regional, Pubmed, Cumed, and Clinical Key in the period 2012-2017, using the key words nephrotic syndrome, glomerulonephritis, diagnosis, therapeutics, comprehensive care. The approach to glomerulopathies is comprehensive, multidisciplinary and individualized. They are the fourth cause of chronic renal disease; the acute post-infectious nephritic syndrome predominates. The clinical method plays a transcendental role at the moment of recognizing and registering their clinical characteristics, etiology and physiopathology, while complementary tests confirm their presence or complications, and therefore an opportune treatment guarantying the healthcare improvement. The most powerful weapon against the challenge of the glomerular disorders is the integrated vision with an individual and social approach led by the physician in the case of these nephropathies in adults.

The relationship between renal warm ischemia time and glomerular loss. An experimental study in a pig model

Abstract Purpose: To investigate the glomerular number after different warm ischemia times. Methods: Thirty two pigs were assigned into four groups. Three groups (G10, G20, and G30) were treated with 10, 20, and 30 minutes of left renal warm ischemia. The sham group underwent the same surgery without renal ischemia. The animals were euthanized after 3 weeks, and the kidneys were collected. Right kidneys were used as controls. The kidney weight, volume, cortical-medullar ratio, glomerular volumetric density, volume-weighted mean glomerular volume, and the total number of glomeruli per kidney were obtained. Serum creatinine levels were assessed pre and postoperatively. Results: Serum creatinine levels did not differ among the groups. All parameters were similar for the sham, G10, and G20 groups upon comparison of the right and left organs. The G30 group pigs' left kidneys had lower weight, volume, and cortical-medullar ratio and 24.6% less glomeruli compared to the right kidney. A negative correlation was found between warm ischemia time and glomerular number. Conclusions: About one quarter of glomeruli was lost after 30 minutes of renal warm ischemia. No glomeruli loss was detected before 20 minutes of warm ischemia. However, progressive glomerular loss was associated with increasing warm ischemia time.

Glomerular loss after arteriovenous and arterial clamping for renal warm ischemia in a swine model

ABSTRACT PURPOSE: To evaluate the glomerular loss after arteriovenous or arterial warm ischemia in a swine model. METHODS: Twenty four pigs were divided into Group Sham (submitted to all surgical steps except the renal ischemia), Group AV (submitted to 30 minutes of warm ischemia by arteriovenous clamping of left kidney vessels), and Group A (submitted to 30 minutes of ischemia by arterial clamping). Right kidneys were used as controls. Weigh, volume, cortical volume, glomerular volumetric density (Vv[Glom]), volume-weighted glomerular volume (VWGV), and the total number of glomeruli were measured for each organ. RESULTS: Group AV showed a 24.5% reduction in its left kidney Vv[Glom] and a 25.4% reduction in the VWGV, when compared to the right kidney. Reductions were also observed when compared to kidneys of sham group. There was a reduction of 19.2% in the total number of glomeruli in AV kidneys. No difference was observed in any parameters analyzed on the left kidneys from group A. CONCLUSIONS: Renal warm ischemia of 30 minutes by arterial clamping did not caused significant glomerular damage, but arteriovenous clamping caused significant glomerular loss in a swine model. Clamping only the renal artery should be considered to minimize renal injury after partial nephrectomies.

Quantitative analysis of the renal aging in rats. Stereological study

ABSTRACT PURPOSE: To evaluate the renal function and the renal histological alterations through the stereology and morphometrics in rats submitted to the natural process of aging. METHODS: Seventy two Wistar rats, divided in six groups. Each group was sacrificed in a different age: 3, 6, 9, 12, 18 and 24 months. It was performed right nephrectomy, stereological and morphometric analysis of the renal tissue (renal volume and weight, density of volume (Vv[glom]) and numerical density (Nv[glom]) of the renal glomeruli and average glomerular volume (Vol[glom])) and also it was evaluated the renal function for the dosage of serum creatinine and urea. RESULTS: There was significant decrease of the renal function in the oldest rats. The renal volume presented gradual increase during the development of the rats with the biggest values registered in the group of animals at 12 months of age and significant progressive decrease in older animals. Vv[glom] presented statistically significant gradual reduction between the groups and the Nv[glom] also decreased significantly. CONCLUSIONS: The renal function proved to be inferior in senile rats when compared to the young rats. The morphometric and stereological analysis evidenced renal atrophy, gradual reduction of the volume density and numerical density of the renal glomeruli associated to the aging process.

Patogênese e tratamento da glomerulonefrite - uma atualização / Pathogenesis and treatment of glomerulonephritis-an update

Resumo A presente revisão traz os conceitos mais atuais acerca dos fatores de risco genéticos, eventos etiológicos, respostas nefritogênicas e tratamento dos principais tipos de glomerulonefrite (GN) imunomediada. Tais patologias incluem GN pós-infecciosa, nefropatia por IgA, doença por anticorpo antimembrana basal glomerular (anti-MBG), vasculite associada a ANCA (VAA) e nefrite lúpica. Apesar da(s) etiologia(s) da maioria dos casos de GN permanecer indefinida, acredita-se que seu início se deva, em grande parte, a insultos ambientais, particularmente na forma de processos infecciosos que deflagram respostas de hospedeiro em indivíduos geneticamente suscetíveis, levando assim a quadros de GN. A concepção mecanicista em torno dessas patologias evoluiu a partir da visão mais antiga de que a maioria seria consequência do aprisionamento glomerular de complexos imunes pré-formados para a percepção atual de que as mesmas, em sua maioria, são doenças autoimunes por natureza mediadas por anticorpos e linfócitos T reativos a auto-antígenos. O tratamento da GN não tem acompanhado os progressos na compreensão de sua patogênese. Os papéis recentemente atribuídos a mediadores mais antigos como complemento e proteínas reguladoras do complemento lançam luz sobre novos alvos terapêuticos.

Abstract This review updates current concepts of the genetic risk factors, etiologic events, nephtitogenic responses and treatment of the major immunologically mediated types of glomerulonephritis (GN). These include post-infectious GN, IgA nephropathy, anti-glomerular basement membrane (GBM) antibody disease, ANCA-associated vasculitis (AAV) and lupus nephritis. Although the etiology(s) of most GNs remain undefined, many are now believed to be initiated by environmental insults, particularly infectious processes, that trigger host responses in genetically susceptible individuals which lead to GN. Mechanistic concepts of these diseases have evolved from earlier views that most were consequent to glomerular trapping of preformed immune complexes to the current view that most of these diseases are auto-immune in nature mediated by both antibodies and T cells reactive with self-antigens. Therapy of GN has lagged behind advances in understanding pathogenesis. Newly appreciated roles for older mediators like complement and complement regulatory proteins offer new therapeutic targets.

Morphologic evaluation of renal function using semi-quantitative method in primary nonproliferative glomerular diseases.

Context: Fibrosis is universally accepted as a poor prognostic finding in renal pathology. Semi-quantitative assessment is widely used for prognostication in pathology. Aims: We propose a semi-quantitative method to prognosticate primary nonproliferative glomerular diseases. Settings and Design: A semi-quantitative method based on Banff schema, 97 classification has been modified to suit the requirements. Glomerular, tubulointerstitial, and vascular compartments were scored independently, and the scores were totaled to obtain total scores. Materials and Methods: Seventy-six renal biopsies were assessed by semi-quantitative scores and the individual compartmental and total scores were correlated with serum creatinine levels. Follow-up was available in 24 cases. Statistical Analysis: Pearson correlation coefficient, two-tailed t test, to determine the P value. Results: P values were significant for the total scores as well as individual compartments. There is a linear correlation between the scores and serum creatinine levels. A total score of ≥5 was significant. Conclusions: The semi-quantitative scoring system based on modified Banff schema, 1997 is useful in prognosticating renal biopsies in primary nonproliferative glomerular diseases.

Low-Intensity physical activity beneficially alters the ultrastructural renal morphology of spontaneously hypertensive rats

INTRODUCTION AND OBJECTIVE: Kidney disorders can cause essential hypertension, which can subsequently cause renal disease. High blood pressure is also common among those with chronic kidney disease; moreover, it is a well-known risk factor for a more rapid progression to kidney failure. Because hypertension and kidney function are closely linked, the present study aimed to observe the beneficial effects of low-intensity physical activity on structural and ultrastructural renal morphology and blood pressure in normotensive and spontaneously hypertensive rats. METHOD: Male Wistar-Kyoto rats and spontaneously hypertensive rats were randomly allocated into four groups: sedentary or exercised Wistar-Kyoto and sedentary or exercised spontaneously hypertensive rats. The exercise lasted 20 weeks and consisted of treadmill training for 1 hour/day, 5 days/week. RESULTS: The exercised, spontaneously hypertensive rats showed a significant blood pressure reduction of 26 percent. The body masses of the Wistar-Kyoto and spontaneously hypertensive strains were significantly different. There were improvements in some of the renal structures of the animals treated with physical activity: (i) the interdigitations of the proximal and distal convoluted tubules; (ii) the basal membrane of the proximal and distal convoluted tubules; and (iii) in the basal membrane, slit diaphragm and pedicels of the glomerular filtration barrier. The spontaneously hypertensive rats also showed a decreased expression of connexin-43. CONCLUSION: Physical exercise could be a therapeutic tool for improving kidney ultrastructure and, consequently, renal function in hypertensive individuals.

Mecanismos fisiopatológicos del desbalance glomérulo-tubular en la hipertensión arterial / Pathophysiological mechanisms of the lack of glomerulus-tubule balance in arterial high blood pressure

Las actuales tendencias e hipótesis para interpretar los mecanismos etiopatogénicos de la hipertensión arterial esencial, involucran al sistema renal como mecanismo preponderante en la regulación a largo plazo de la presión arterial y la existencia en él de algún fenómeno que puede conllevar a desbalance glomérulo-tubular, con preponderancia tubular Aunque el análisis de este último hecho no ha sido como tal abordado en la patogénesis del síndrome hipertensivo. Con el objetivo de interpretar el papel del desbalance glomérulo-tubular, con preponderancia tubular en la fisiopatología de la hipertensión arterial como fenómeno en el que confluyen múltiples mecanismos fisiopatológicos renales ya descritos, se revisaron estos últimos, de forma integrada y su relación causal con el desbalance glomérulo-tubular, con preponderancia tubular. La preponderancia tubular, punto común de los mecanismos que se discuten, favorece la disminución de la excreción fraccional de Na+, la retención hidrosalina y la elevación de la presión arterial

The current trends and hypotheses to know the etiopathogenesis mechanisms of the essential arterial high blood pressure involved the renal system as a prevailing mechanism in the long-term regulation of arterial pressure and the existence in it of some phenomenon that could lead to a glomerulus-tubule lack of balance with tubular preponderance. Although the analysis of this latter fact, has not been approached as such in pathogenesis of hypertensive syndrome. With the aim of to interpret the role of glomerulus-tubule lack of balance with tubular preponderance in pathophysiology of arterial high blood pressure as a phenomenon in which converging multiple renal pathophysiological mechanisms already described, these latter were reviewed in a integrated way and its causal relation with the above mentioned lack of balance with tubular preponderance. This preponderance, a common point of discussed mechanisms, favors the decrease of a fractional releasing of Na+, the hydrosaline retention and the raise of arterial pressure

Maternal undernutrition and the offspring kidney: from fetal to adult life

Maternal dietary protein restriction during pregnancy is associated with low fetal birth weight and leads to renal morphological and physiological changes. Different mechanisms can contribute to this phenotype: exposure to fetal glucocorticoid, alterations in the components of the renin-angiotensin system, apoptosis, and DNA methylation. A low-protein diet during gestation decreases the activity of placental 11ß-hydroxysteroid dehydrogenase, exposing the fetus to glucocorticoids and resetting the hypothalamic-pituitary-adrenal axis in the offspring. The abnormal function/expression of type 1 (AT1R) or type 2 (AT2R) AngII receptors during any period of life may be the consequence or cause of renal adaptation. AT1R is up-regulated, compared with control, on the first day after birth of offspring born to low-protein diet mothers, but this protein appears to be down-regulated by 12 days of age and thereafter. In these offspring, AT2R expression differs from control at 1 day of age, but is also down-regulated thereafter, with low nephron numbers at all ages: from the fetal period, at the end of nephron formation, and during adulthood. However, during adulthood, the glomerular filtration rate is not altered, due to glomerulus and podocyte hypertrophy. Kidney tubule transporters are regulated by physiological mechanisms; Na+/K+-ATPase is inhibited by AngII and, in this model, the down-regulated AngII receptors fail to inhibit Na+/K+-ATPase, leading to increased Na+ reabsorption, contributing to the hypertensive status. We also considered the modulation of pro-apoptotic and anti-apoptotic factors during nephrogenesis, since organogenesis depends upon a tight balance between proliferation, differentiation and cell death.

Renal tubular and glomerular function in children with iron deficiency anemia

Iron deficiency anemia [IDA] resulting from lack of sufficient iron for synthesis of hemoglobin is most common hematologic disease of infancy and childhood. There is little information about the renal function in iron deficiency anemia. The aim of the present study was to examine the renal function in children with iron deficiency anemia. This case-control study was performed in children with iron deficiency anemia [n=20] and healthy age matched subjects [n=20]. Blood and urine samples were obtained for hematological and biochemical investigation. Statistical analysis was performed by unpaired sample t-test and Pearson's correlation coefficient. Fractional excretion of sodium [FENa+] was significantly higher in children with iron deficiency anemia than control subjects [P=0.006]. There was no significant difference in the level of urine specific gravity, calcium/creatinine ratio, beta 2-microglobulin and creatinine clearance between case and control groups [P>0.05]. There was no correlation between FENa and Hb [r=0.13, P=0.57], FENa+ and Fe+2 [r=0.079, P=0.72], FENa+ and TIBC [r=-0.083, P=0.71], FENa+ and ferritin [r=0.039, P=0.86] as well as Hb and beta 2-microglobulin [r=0.02, P=0.37] in IDA patients. The results showed that FENa+ was higher in children with iron deficiency anemia than in normal subjects. The findings revealed evidence of tubular damage in IDA; this needs confirmation by more investigation

Determination of renal function in long-term heart transplant patients by measurement of urinary retinol-binding protein levels

Significant improvements have been noted in heart transplantation with the advent of cyclosporine. However, cyclosporine use is associated with significant side effects, such as chronic renal failure. We were interested in evaluating the incidence of long-term renal dysfunction in heart transplant recipients. Fifty-three heart transplant recipients were enrolled in the study. Forty-three patients completed the entire evaluation and follow-up. Glomerular (serum creatinine, creatinine clearance measured, and creatinine clearance calculated) and tubular functions (urinary retinol-binding protein, uRBP) were re-analyzed after 18 months. At the enrollment time, the prevalence of renal failure ranged from 37.7 to 54 percent according to criteria used to define it (serum creatinine > or = 1.5 mg/dL and creatinine clearance <60 mL/min). Mean serum creatinine was 1.61 ± 1.31 mg/dL (range 0.7 to 9.8 mg/dL) and calculated and measured creatinine clearances were 67.7 ± 25.9 and 61.18 ± 25.04 mL min-1 (1.73 m²)-1, respectively. Sixteen of the 43 patients who completed the follow-up (37.2 percent) had tubular dysfunction detected by increased levels of uRBP (median 1.06, 0.412-6.396 mg/dL). Eleven of the 16 patients (68.7 percent) with elevated uRBP had poorer renal function after 18 months of follow-up, compared with only eight of the 27 patients (29.6 percent) with normal uRBP (RR = 3.47, P = 0.0095). Interestingly, cyclosporine trough levels were not different between patients with or without tubular and glomerular dysfunction. Renal function impairment is common after heart transplantation. Tubular dysfunction, assessed by uRBP, correlates with a worsening of glomerular filtration and can be a useful tool for early detection of renal dysfunction.

Efecto de diferentes grados de actividad física en la presentación de cambios anatómicos e histológicos relacionados con el envejecimiento renal / Effect of different levels of physical activity upon anatomical and histologic changes related to renal aging

Objetivos: determinar los cambios anatómicos del ejercicio en el envejecimiento renal. Metodología: estudio longitudinal experimental durante 54 semanas. Se tomaron 120 ratones machos cepa Suizo, los cuales según su actividad se dividieron en 3 grupos: sedentarios, normales y activos. El ejercicio se moduló con el espacio habitacional y el acceso al alimento. Se sacrificaron 3 animales por grupo desde la 9ª semana de edad cada 9 semanas. Se consideraron animales jóvenes aquellos menores de 27 semanas y viejos los mayores de 36. Los ratones y sus riñones se pesaron, y se estableción la relación peso riñones/peso ratón. Del riñón izquierdo de cada animal se midió la corteza y se realizó el estudio histológico con las coloraciones clásicas. Los cortes fueron analizados por 2 patólogos que no conocían el propósito del estudio; describieron cambios glomerulares y túbulo intersticiales, los cuales se clasificaron de nulos a severos. Se midieron áreas glomerulares y la relación luz/pared arterial. Resultados: El máximo crecimiento renal se observó a las 18 semanas. En la semana 54, los sedentarios tuvieron menor espesor cortical (2288,65 ± 552,75) que los normales (2502,7 ± 163,81) y los activos (2609,46 ± 273,28), con n=3 para todos los grupos. El área glomerular fue significativamente menor (P= 0,035) en sedentarios (8657,33 ± 1954,38), comparativamente con los activos (10318,64 ± 2425,14), pero entre los normales (9791,52 ± 2211,63) y los otros dos grupos no existieron diferencias significativas: n=18 para cada grupo. La atrofia tubular en animales viejos fue del 55,5 por ciento en los sedentarios, mayor que en normales y activos, en los cuales fue del 44,4 por ciento no significativo. La nefritis intersticial fue menor en normales (55,5 por ciento), en comparación con los sedentarios y activos (77,7 por ciento) no significativo. Conclusión: el grupo sedentario presentó mayor compromiso estructural en el envejecimiento renal. Aunque el ejercicio moderado puede li...

Microalbuminuria as a predictor of early glomerular injury in children with sickle cell disease.

OBJECTIVE: A cross sectional study was carried out to determine the prevalence of microalbuminuria in the pediatric patients with sickle cell disease. METHODS: The study was carried out on 64 pediatric patients aged less than 14 years with documented HbSS, HbAS and HbS beta thalassemia, Microalbuminuria was estimated using single radial immuno diffusion technique. Majority of the study subjects were of HbSS type. 38.5% had symptoms for > 2 years. 18.8% of the study population had significant microalbuminuria (19.2% of SS type and 18.8% of Hb AS types). RESULT: Microalbuminuria excretion was significantly more in patients > 9 years of age as compared to young patients (p < 0.05). Mean serum creatinine levels did not show any significant difference in the various study groups. CONCLUSION: Microalbuminuria estimation is a very important clinical marker of preclinical glomerular damage in patients with sickle cell disease. It estimation would help in the early detection of such patients and prompt initiation of therapy.

Renal dysfunction in patients with sickle cell anemia or sickle cell trait

Patients with sickle cell anemia (Hb SS) or sickle cell trait (Hb AS) may present several types of renal dysfunction; however, comparison of the prevalence of these abnormalities between these two groups and correlation with the duration of disease in a large number of patients have not been thoroughly investigated. In a cross-sectional study using immunoenzymometric assays to measure tubular proteinuria, microalbuminuria, measurement of creatinine clearance, urinary osmolality and analysis of urine sediment, we evaluated glomerular and tubular renal function in 106 adults and children with Hb SS (N = 66) or Hb AS (N = 40) with no renal failure (glomerular filtration rate (GFR)>85 ml/min). The percentage of individuals with microalbuminuria was higher among Hb SS than among Hb AS patients (30 vs 8 per cent, P<0.0001). The prevalence of microhematuria was similar in both groups (26 vs 30 per cent, respectively). Increased urinary levels of retinol-binding protein or ß2-microglobulin were detected in only 3 Hb SS and 2 Hb AS patients. Urinary osmolality was reduced in patients with Hb SS or with Hb AS; however, it was particularly evident in Hb SS patients older than 15 years (median = 393 mOsm/kg, range = 366-469) compared with Hb AS patients (median = 541 mOsm/kg, range = 406-722). Thus, in addition to the frequently reported early reduction of urinary osmolality and increased GFR, nondysmorphic hematuria was found in 26 and 30 per cent of patients with Hb SS or Hb AS, respectively. Microalbuminuria is an important marker of glomerular injury in patients with Hb SS and may also be demonstrated in some Hb AS individuals. Significant proximal tubular dysfunction is not a common feature in Hb SS and Hb AS population at this stage of the disease (i.e., GFR>85 ml/min)

Nefritis colagena / Collagen nephritis

En los últimos años se ha descripto un nuevo tipo de glomerulopatía primaria, denomminada nefritis colágena, caracterizada por la acumulación masiva de colágeno fibrilar en mesangio y membrana basal glomerular sin asociación con patología osteoarticular. Se comunica aquí el primer caso en nuestro medio. Se trata de una paciente de 26 años con síndrome nefrótico y progressiva caída del filtrado cuya biopsia renal mostró una esclerosis focal y segmentaria en la microscopia óptica. La evaluación ultraestructural reveló acúmulos en membrana basal y mesangio de colágeno fibrilar que permitió el diagnóstico de esta entidad.

Función renal en el infarto agudo del miocardio / Renal function in acute myocardial infarction

Introducción. El infarto agudo del miocardio frecuentemente se asocia a disfunción renal. Objetivo. Reportar las alteraciones de la función renal en pacientes con infarto agudo del miocardio. Pacientes y métodos. Estudiamos prospectivamente 25 pacientes que ingresaron a una unidad de cuidados coronarios/unidad de cuidados intensivos (UCC/UCI) con infarto agudo del miocardio no complicado. Se hizo seguimiento de la función renal a las 24 y 72 horas de evolución a través de la evaluacion de las fuciones glomerular y tubular. Resultados. La diuresis disminuyó significativamente después de 72 horas; la función glomerular no cambió a las 24 horas pero se deterioró 72 horas más tarde; la función tubular se alteró durante las primeras horas y se normalizó al final del estudio; solo un paciente se complicó con isuficiencia renal aguda. Conclusión. La función renal se alteró transitoriamente durante las primeras 72 horas de evolución del infarto agudo del miocardio. La insuficiencia renal es poco frecuente

Glomerular hemodynamics during abortion induced by RU 486 and sepsis in rats

1. Acute renal failure is a very common consequence of septic abortion. Whole kidney and glomerular hemodynamics were evaluated in virgin (V), pregnant (PREG) and aborted (ABOR) euvolemic Munich-Wistar rats before and after E. coli (0111-B4) endotoxin (LPS) infusion in order to evaluate the effect of septic abortion on the renal microcirculation. 2. Abortion induced by RU 486 blunted the increase in glomerular filtration rate (GFR) induced by normal pregnancy (0.86 +/- 0.03 vs 0.63 +/- 0.07 ml/min, P < 0.05). In virgin rats, RU 486 did not modify the parameters of renal function. Significant alterations occurred in whole kidney and single nephron function. However, the changes in whole kidney function in the ABOR group were significantly higher than those observed for the V group (reductions in GFR were 42 in V and 80 in ABOR, RPF decreased 34 in V and 76 in ABOR, TRVR increased 82 in V and 400 in ABOR). 3. Mean single nephron glomerular filtration rate (SNGFR) was reduced in all groups after LPS (44 in V, 43 in V+RU, 55 in PREG, 60 in ABOR), due to significant decreases in glomerular plasma flow rate, QA (42 in V, 55 in V+RU, 53 in PREG, 57 in ABOR) and in glomerular ultrafiltration coefficient, Kf (46 in V, 47 in V+RU, 45 in PREG, 67 in ABOR). 4. These data show that LPS induced significant alterations in renal function in all groups. However, aborted rats were more sensitive to the effects of LPS than V rats. These results indicate that abortion may potentiate the effects of endotoxemia on renal function elevating the extent of acute renal failure and thus the mortality rate.