Preservación de cápsula prostática y vesículas seminales en cirugía radical del cáncer vesical órgano confinado / Prostate and seminal vesicles sparing radical cystectomy for organ-confined bladder cancer

En los últimos años se ha incrementado el interés por la preservación de la cápsula prostática y vesículas seminales en la cirugía radical del cáncer vesical localmente confinado. Las indicaciones para esta técnica son pacientes jóvenes en buenas condiciones, tumores órgano confinados, cuello vesical indemne y ausencia de sospecha de cáncer prostático (CP) sincrónico. La preservación sémino-prostática logra mejores resultados postoperatorios en relación a la continencia, capacidad eréctil y eyaculatoria, comparada con la técnica quirúrgica estándar. Nuestro Servicio decidió evaluar esta situación estudiando en nuestros pacientes sometidos a cistoprostatectomía radical (CPR) por cáncer vesical estadio clínico T2, la incidencia de cáncer prostático incidental (CPI) y el compromiso neoplásico de la uretra prostática. De un total de 17 pacientes sometidos a CPR en nuestro Servicio entre junio de 2002 y abril de 2004 por cáncer vesical órgano confinado, se seleccionaron 15 casos con estadio pT2- pT3 (edad promedio 64 años, rango 52-72). Se descartó un paciente por presentar sospecha clínica de cáncer de próstata con confirmación histopatológica a la biopsia por punción ecodirigida y de la pieza operatoria, y otro paciente en quien se demostró con biopsia preoperatoria, una invasión del tumor vesical transicional a cuello vesical y uretra prostática. En cada caso seleccionado se estudiaron detenidamente los resultados de la anatomía patológica con especial énfasis en determinar la presencia de un CPI y/o la invasión neoplásica de la uretra prostática. De los pacientes sometidos a la cirugía radical estándar (n=15), ninguno manifestó sospecha clínica ni serológica de CP previo a la cirugía. Sólo en un caso se evidenció un CPI Gleason 3+3 intraglandular en50 por ciento del tejido prostático (paciente de 63 años con CPR más neovejiga ileal ortotópica). Además de este caso no se observó ninguna otra neoplasia a nivel prostático...

In the last years the interest for preserving the prostatic capsule and seminal vesicles in the radical surgery for organ confined bladder cancer has increased. The indications for this technique are: young patients in good conditions, organ confined tumors, unharmed bladder neck and no suspicion of a synchronic prostate cancer (PC). Prostate and seminal sparing achieves better results after surgery in regard to continence, erectile and ejaculatory function, compared with the standard surgical technique. Our Department decided to assess this situation in our patients subjected to radical cystoprostatectomy (RCP) for bladder cancer with clinical stage cT2, in regard to the incidence of incidental prostate cancer (IPC) and the tumoral extension to the prostatic urethra. 17 patients were indicated a RCP for organ confined bladder cancer in our Department between June 2002 and April 2004. Of these, 15 cases were identified with stage pT2-pT3 (mean age 64 years, range 52 to 72). Two patients were not included in the series: one patient with clinical suspicion for prostate cancer, (Prostate cancer was then confirmed by ultrasound guided biopsy and final pathology report after surgery), and another patient with verified transitional cell carcinoma invasion to the bladder neck and prostatic urethra. In each selected case the pathological features were carefully studied with special emphasis in determine the presence of a IPC or the tumoral invasion of the prostatic urethra. Any patient with indication of radical surgery (n=15) showed clinical or serological suspicion of PC preoperatively. In only one case, a intraglandular IPC score Gleason 3+3 was demonstrated in 50 percent of the prostatic tissue (63 year old patient with RPC and orthotopic ileal neobladder). Besides this case, no other neoplasia was observed in the prostate, prostatic urethra or seminal vesicles. A 6.6 percent of the RCP of our series presented a IPC...

Duloxetina versus placebo en el tratamiento de la incontinencia urinaria de esfuerzo: ensayo clínico controlado en mujeres de la III Región de Atacama / Duloxetine vs. placebo in the stress incontinence treatment: controled clinical assay in women of Atacama area

Actualmente para la IOE los tratamientos aceptados son el entrenamiento muscular pélvico, intervenciones de hábitos y perfil biométrico y la cirugía, no estando plenamente establecido el tratamiento farmacológico para esta patología. La efectividad de la Duloxetina está relacionada con su capacidad de inhibición de la recaptación pre sináptica neuronal de serotonina y norepinefrina en el espacio sináptico del sistema nervioso central, promoviendo un tono esfinteriano uretral más potente durante el estrés físico y llenado vesical. En la actualidad no se han reportado experiencias nacionales con este fármaco para el tratamiento de la IOE en mujeres. Objetivos: Determinar la eficacia y tolerancia de la Duloxetina en el tratamiento médico de la IOE, evaluando la mejoría en la calidad de vida, la disminución de la frecuencia de escapes urinarios y los efectos adversos. Pacientes y método: Ensayo prospectivo randomizado doble ciego que incluyó 64 mujeres no embarazadas de 23 a 73 años (promedio 54 años), con síntomas predominantes de IOE de más de 3 meses de evolución. Los criterios de inclusión fueron: frecuencia de episodios de incontinencia (FEI) >= 4 a la semana, ausencia de síntomas predominantes de urge-incontinencia, frecuencia miccional (FM) normal (<= a 7/2), capacidad vesical >= a 400 ml. medida por infusión supina y prueba de tos y pañal positivas. Se realizó estudio urodinámico a un grupo aleatorio de 30 pacientes. Las pacientes fueron randomizadas recibiendo Duloxetina (40 mg c/12 horas vo) o placebo 2 veces al día, por 3 meses. Todas ellas fueron controladas mensualmente, evaluando la FEI, FM, cuestionario de calidad de vida por incontinencia (I-QOL), efectos adversos y adhesión al tratamiento. Se utilizó el software SPSS(r) para el análisis de resultados incluyendo test de Wilcoxon y Ancova. Resultados: El promedio de la FEI disminuyó significativamente con Duloxetina versus placebo (59 por ciento vs 28 por ciento, p<0,01), siendo mayor aún en el gru...

Introduction: The stress urinary incontinence (SUI) is the most common of the urinary incontinences and it has become a relevant urological and public health problem all over the world. Currently the most accepted forms of therapy for SUI are pelvic floor muscle training, behavioural and biometrical profile interventions and surgery, pharmacological treatment is not fully established for this pathology. The entrenaeffectiveness of duloxetine is related with its ability of inhibit serotonin and norepinephrine reuptake in the synaptic space of the central nervous system, increasing the urethral sphincter tone during the physical stress and bladder filling. Currently, no national experiences have been reported with this drug for the medical treatment of the SIU in women. Objectives: To assess the efficacy and safety of duloxetine in the medical treatment of SIU, valuating improvements in life quality, the diminishing of urinary leakage frecuency and adverse events. Patients and methods: Prospective double-blind randomized study which enrolled 64 nonpregnant women aged 23 to 73 years (54 years average), with a predominant symptom of SIU of more than 3 months of evolution. The inclusion criteria were: weekly incontinence episode frecuency (IEF) of 4 or greater, the absence of predominant symptoms of urge incontinence, normal diurnal and nocturnal frecuency (≤ a 7/2), a bladder capacity of 400 ml or greater measured with supine infusion, and a positive cough stress test and stress pad test. Urodynamic study was assessed to a random group of 30 patients. Subjects were randomized to duloxetine (40 mg BID) or placebo BID, for 3 months. All of them were controlled monthly, evaluating the IEF, voiding frecuency, Incontinence Quality of Life (I-QOL) questionnaire, adverse events and adhesion to treatment. SPSS® was used to analize the results including the Wilcoxon and Ancova tests. Results: There was a significant decrease in IEF with duloxetine compared with placebo...

Resultados de la técnica TOT con anestesia peridural en el tratamiento quirúrgico de la incontinencia urinaria de esfuerzo / TOT procedure results under peridural anesthesia in the surgical treatment of stress urinary incontinence

Se evalúa prospectivamente la eficacia y seguridad de la técnica de sling transobturador (TOT) realizada mediante la utilización de anestesia peridural (AP), en el tratamiento quirúrgico de la IOE femenina. Se estudian 52 pacientes mujeres, portadoras de IOE y/o incontinencia urinaria mixta (IUM), asociadas con hipermovilidad uretral, las que fueron sometidas a TOT bajo AP, entre junio de 2003 y abril de 2005, en nuestra Institución. El promedio de edad fue 57,1 años (43 a 76). 20 pacientes (38 por ciento) presentaban IOE pura y 32 pacientes (62 por ciento) tenían IUM. La malla utilizada en todos los casos fue de polipropileno no elástico. En todas la pacientes se realizó AP que permitió mantener el control voluntario del piso pelviano. Se utilizó un acceso perineal percutáneo con agujas helicoidales, posicionando la malla a nivel medio suburetral. La correcta tensión de la malla se logró hasta poder evidenciar la desaparición de escape uretral con vejiga llena, mediante maniobras de Valsalva efectuadas por la paciente, en posición de Trendelemburg invertido de 40º. El promedio de la duración de la cirugía fue de 26 minutos. La sonda (SUV) fue retirada antes de 24 horas postoperatorias. Todos los pacientes tuvieron un seguimiento postoperatorio con cuestionario de síntomas, examen clínico, test de escape uretral con vejiga llena y medición de residuo postmiccional (RPM) cada 3 meses. En la IUM, se inició tratamiento con oxibutinina o trospio 2 meses antes y por 2 meses postoperatorios. El promedio de seguimiento fue de 1,2 años (3-24 meses), al 6º mes el 92 por ciento estaba completamente curado de su IOE. Al 1º año de seguimiento un 88 por ciento (n=46) estaba sin IOE y un 82 por ciento (n=43) no refería incontinencia de urgencia. No se describieron accidentes intraoperatorios. No se presentó retención aguda de orina (RAO) post retiro de SUV, en tanto que al año de seguimiento se evidenciaron sólo 3 pacientes (6 por ciento) con RPM elevado (>80 ml). Creemos...

Fusión esplenogonadal: reporte de 1 caso / Splenogonadal fusion: report of one case

Se presenta el caso de un paciente operado por tumor testicular izquierdo, cuyo estudio anatomopatológico concluyó una fusión esplenogonadal. Se entrega información respecto a esta rara malformación y se mencionan herramientas diagnósticas que pueden ayudar al diagnóstico preoperatorio con la consiguiente reducción de la cirugía radical testicular.

Validación de un modelo predictivo para la presencia y localización del compromiso extracapsular en cancer de próstata / Validation of predictive model for the presence and location of the extracapsular commitment in prostate cancer

El conocimiento de la presencia y localización de la extensión extracapsular (EEC) en el cáncer de próstata antes de la cirugía, ayuda sustancialmente a la toma de decisiones y prevee resultados postoperatorios más confiables para el Urólogo y su paciente. Hasta antes de la creación del nomograma de Ohori no existía un modelo predictivo que determinar la presencia y localización de la invasión extracapsular en el cáncer clínicamente localizado. El objetivo del estudio fue validar la utilidad clínica de un modelo predictivo para establecer la probabilidad lado específica de la EEC en la prostatectomía radical (PR), basado en la utilización de algunas variables clínico-patológicas del cáncer prostático. Estudiamos 48 hombres con estadio clínico TIc-T3 sometidos a PR, divididos en 2 grupos: 17 pacientes que presentaron compromiso extracapsular en la biopsia postoperatoria (estadios pT3) y otro grupo de 31 pacientes sin EEC (estadios pT2). A todos se les aplicó retrospectivamente las variables predictivas del nomograma de Ohori las que incluían para cada lóbulo: el estadio T clínico, el score Gleason, porcentaje de muestras positivas, porcentaje de cáncer en las muestras y el PSA preoperatorio. Las predicciones obtenidas en ambos grupos fueron confrontadas con el resultado anatomopatológico definitivo de la pieza operatoria. Del total de lóbulos prostáticos con EEC (n=20 lóbulos) el nomograma arrojó una probabilidad de 50 por ciento en todos ellos menor o igual al 80 por ciento en 90 por ciento de éstos (n=18 lóbulos). Al analizar los 76 lóbulos sin EEC obtuvimos una probabilidad mayor o igual al 10 por ciento e incluso menor o igual al 5 por ciento en 90 por ciento de los especímenes (n=69 lóbulos). Recomendamos el uso rutinario de este modelo predictivo en la práctica clínica, ya que es una herramienta válida para la elección del tipo de cirugía y principalmente en la decisión de preservar o no los nervios cavernosos.

Epidemiología de los cánceres urológicos en la Tercera Región de Atacama / Epidemiology of urological cancers in the Tercera Región de Atacama

Si se consideran todos los cánceres, el cáncer de próstata es el tumor maligno más frecuentemente diagnosticado en E.E.U.U., ocupando el segundo lugar entre las causas de muerte por cánceres en hombres, y el sexto lugar en la incidencia general de cánceres. En relación a las otras neoplasias génitourinarias, los registros internacionales de incidencia y mortalidad para cáncer de vejiga, renal, testicular y peneano son significativamente menores. En nuestro país no se conocen cifras de incidencia real de estas patologías, existiendo registros publicados sólo para algunas regiones y provincias de Chile. El propósito de esta investigación es determinar la magnitud de las tasas de incidencia anuales de estas neoplasias en la III Región de Atacama durante el período anual de septiembre de 2002 a agosto de 2003. Se observaron tasas de incidencia sorprendentemente altas para cáncer de próstata en comparación con otras regiones de Chile (58 x 100.000 hombres y un índice Swarop de 317,4 x 100.000 hombres mayores de 50 años). Para cáncer vesical, la tasa de incidencia fue de 9,40 x 100.000 habs. y 16,93 x 100.000 si consideramos sólo población masculina. La tasa de incidencia real para cáncer renal fue de 6,95 x 100.000 habs. con un índice Swarop de 35,25 x 100.000 habs. mayores de 50 años. En relación al cáncer testicular y de pene se obtuvieron tasas de incidencia de 7,25 x 100.000 hombres y 2,41 x 100.000 hombres, respectivamente. Además, se describen otros atributos y variables epidemiológicas como edad promedio, rangos de edad, tasas ajustadas por grupo etáreo y se esbozan ciertas apreciaciones en relación a eventuales factores de riesgo.

[Relationship between serum testosterone levels and prostatic cancer]. / Relación entre niveles de testosterona en suero y cáncer prostático.

INTRODUCTION: The association between testosterone and prostate cancer badly is understood. The testosterone levels are not conclusive to distinguish benign prostate processes of malignant. The objective of our work is to determine the relation between levels of serum testosterone and prostate cancer. MATERIAL AND METHOD: 38 patients with prostate cancer and a control group of 32 were studied in prospective form, with ages that fluctuated between the 50 and 80 years. The total and free testosterone was determined by radio-immunoensayo. The statistical analysis was descriptive inferential, with bands of 95% confidence. RESULTS: The average values of total and free testosterone, were significantly smaller in patients with prostate cancer. Any correlation between gleason, prostate antigen and stage with testosterone, was not demonstrated. CONCLUSIONS: Our work demonstrated that the testosterone is significantly smaller in the patients with prostate cancer that in the controls.

Inflammation, not hyperhomocysteinemia, is related to oxidative stress and hemostatic and endothelial dysfunction in uremia.

BACKGROUND: Several cardiovascular risk factors are present in patients with chronic renal failure (CRF), among which are systemic inflammation and hyperhomocysteinemia. Increased oxidative stress, endothelial activation/dysfunction, and coagulation activation are considered integral components of the inflammatory response, but have also been proposed as mediators of plasma homocysteine (tHcy)-induced cell damage. Using correlation analysis, we assessed the relative contributions of inflammation and hyperhomocysteinemia in the abnormal oxidative stress, endothelial activation/dysfunction, and hemostasis activation in patients with CRF. METHODS: The relationships of inflammatory proteins and tHcy with plasma markers of these processes were studied in 64 patients with CRF (serum creatinine 526 +/- 319 micromol/L) on conservative treatment, comparing the results with healthy controls (N = 15 to 40, depending on the measured variable) of similar sex and age. RESULTS: Patients had significant increases in inflammatory cytokines (TNF-alpha and IL-8) and acute-phase proteins (C-reactive protein, fibrinogen and alpha1-antitrypsin). tHcy was increased in 87.5% of patients (mean = 27.1 micromol/L, range 6.5 to 118). Patients had significant increases in (1) indices of oxidative stress: TBARS (thiobarbituric acid-reactive species), a marker of lipid peroxidation and AOPP (advanced oxidation protein products), a marker of protein oxidation; (2) endothelial cell markers such as von Willebrand factor (vWF:Ag), soluble ICAM-1 and soluble thrombomodulin (sTM); (3) markers of intravascular thrombin generation: thrombin-antithrombin complexes (TAT) and prothrombin fragment F(1+2) (PF(1+2)); and (4) indices of activation of fibrinolysis: plasmin-antiplasmin complexes (PAP), fibrin degradation products (FnDP) and fibrinogen degradation products (FgDP). tHcy was significantly correlated with plasma creatinine (r = 0.29, P < 0.018) and with serum folate (r = -0.38, P < 0.002). However, no significant correlations were observed between tHcy and TBARS, AOPP, vWF:Ag, sICAM-1, sTM, TAT, F(1+2), sTF, PAP, FnDP, and FgDP. Conversely, acute-phase proteins showed significant, positive correlations with most markers of oxidative stress, endothelial dysfunction and hemostatic activation. CONCLUSIONS: Systemic inflammation, which is closely associated with augmented oxidative stress, endothelial cell dysfunction and hemostatic activation, emerges as a major cardiovascular risk factor in CRF. tHcy is unrelated to these events. Thus, alternative mechanisms through which hyperhomocysteinemia could predispose to vascular lesion and thrombotic events in CRF needs to be investigated.

Increased activation of protein C, but lower plasma levels of free, activated protein C in uraemic patients: relationship with systemic inflammation and haemostatic activation.

Chronic renal failure (CRF) courses with both systemic inflammatory reaction and haemostatic activation. We explored the relationship of these processes with plasma levels of free, activated protein C (APC) and complexes of APC with its inhibitors in patients with CRF under conservative treatment. Plasma concentrations of inflammatory cytokines [tumour necrosis factor alpha (TNFalpha) and interleukin 8], acute-phase proteins (C-reactive protein, fibrinogen, alpha1-anti-trypsin and von Willebrand factor), and markers of haemostatic activation (thrombin-anti-thrombin complexes, plasmin-anti-plasmin complexes, and fibrin and fibrinogen degradation products) were higher in patients than in controls. Inflammatory and haemostatic markers were significantly and positively correlated. Total plasma APC and APC:alpha1-anti-trypsin (alpha1AT) complexes were 44% and 75% higher in patients than in controls (P = 0.0001), whereas free APC was 20% lower (P < 0.015). No significant difference was observed in APC:protein C inhibitor (PCI) complexes between both groups. The free/total APC ratio was significantly lower in patients than in controls (P < 0.0001). Total plasma APC and APC:alpha1AT were positively correlated with activation markers of haemostasis and acute-phase proteins, whereas free APC was inversely correlated with plasma levels of creatinine, acute-phase proteins and fibrin degradation products (FnDP). Systemic inflammation and activation of haemostasis are interrelated processes in CRF. APC generation was increased in response to elevated thrombin production, but the inflammatory reaction, associated with increased synthesis of alpha1AT, reduced its anticoagulant effect. Lower free plasma APC in CRF may be pathogenically associated with atherothrombosis, a major cause of death in this disease.

Non-traditional risk factors for atherosclerosis.

During the last 10 years, several "non-traditional" risk markers for atherosclerosis have been identified. Among them, new markers of lipoprotein metabolism (i.e. lipoprotein [a]), endothelial dysfunction (i.e. homocysteine), hemostasis (i.e. fibrinogen) and inflammation (i.e. C-reactive protein) have been linked to an excessive risk of cardiovascular disease. These factors should help the clinician to better identify individuals at risk of premature atherosclerotic disease and/or improve the predictive value of established risk factors for atherosclerosis. Finally, these factors are expected to improve the knowledge in the pathophysiology of cardiovascular diseases, and perhaps to impact future therapeutic decisions. In this review article, we will analyze the markers in which there are at least some evidence to support their acceptance as "non-traditional risk factors" for atherosclerotic disease.

Tranexamic acid inhibits fibrinolysis, shortens the bleeding time and improves platelet function in patients with chronic renal failure.

BACKGROUND: A defect in platelet function is the main determinant of the prolonged bleeding time in chronic renal failure (CRF). We previously reported a significant correlation between platelet abnormalities and elevated plasma markers of plasmin and thrombin generation. Our aim was to explore the effect of inhibiting both plasmin action with tranexamic acid (TA) and thrombin production with low molecular weight heparin (LMWH), on the bleeding time (BT) and platelet function in patients with CRF. METHODS: 37 patients with CRF (mean creatinine 8.6 +/- 4.4 mg/dl) under conservative treatment, with prolonged BT, entered this study and received TA during 6 days, with (n = 24) and without LMWH (n = 13). BT, platelet aggregation/secretion, platelet granule contents, von Willebrand factor and parameters of coagulation and fibrinolysis were recorded before and at the end of treatment. RESULTS: The BT was shortened in 26/37 (67%) patients. This effect was associated with significant improvement of platelet aggregation and secretion, with decrease to a normal range of fibrin/fibrinogen degradation products, mild increase in plasmin-antiplasmin complexes and pronounced reduction of circulating plasminogen. No differences were seen among patients with or without LMWH. No serious side effects or complications were observed. INTERPRETATION: These findings indicate that the activation of fibrinolysis plays a significant role in the defect of primary hemostasis in patients with CRF. Inhibition of plasmin activity with TA shortens the BT and improves platelet function in the majority of patients with severe disease.

Tuberculosis genitourinaria en la Araucania: experiencia en el Hospital Regional de Temuco / Genitourinary tuberculosis at Araucanía: experience at Hospital Regional de Temuco

Se estudian 62 casos con tuberculosis genitourinaria tratados entre 1989 y 1996. Corresponden a 41 hombres y 21 mujeres con un promedio de edad de 42,6 años. El 58,1 por ciento habita en localidad rural y un 37,1 por ciento tiene ascendencia mapuche. El 32,3 por ciento tiene antecedentes de tuberculosis anterior o concomitante. La latencia entre inicio de síntomas y diagnóstico fue de 13,1 meses, debutando el cuadro principalmente con hematuria macróscopica (45,2 por ciento), irritación vesical (44,9 por ciento) y dolor y/o aumento de volumen escrotal. La confirmación diagnóstica fue realizada en un 83,9 por ciento mediante cultivo y/o biopsia. Urocultivo de Koch fue positivo en un 69,4 por ciento. En el 90 por ciento la ecotomografía renal y un 74 por ciento la pielografía endovenosa resultaron alteradas, siendo el órgano más afectado el riñón. Fueron intervenidos quirúrgicamente 21 pacientes (33,9 por ciento). En 11 casos la evolución fue hacia una insuficiencia renal crónica. Todos recibieron tratamiento médico con esquema abreviado de 7 meses

Reproductive seasonality of corriedale rams under extensive rearing conditions.

The objective of the present study was to describe seasonal changes in scrotal circumference (SC), live weight (LW), sperm morphology and plasma levels of testosterone (T) and thyroxine (T4) in young Corriedale rams reared under extensive conditions typical for the southern Latin American region. A total of 31 Corriedale rams, 11 months of age and with a LW of 36 +/- 1.1 kg and (SC) of 23.0 +/- 0.5 cm at the beginning of the experiment (September) were kept on natural pastures. At monthly intervals LW was recorded, animals were clinically examined, and SC was measured. None of the animals were used for breeding. Fifteen animals were randomly selected and bled once a month from January to December and plasma concentrations of T and T4 were determined. In addition, one semen sample was collected by electroejaculation and morphological studies were performed. The mean individual LW increase was 18 kg (50% of the initial LW) during the experiment (p < 0.01). LW decreased in autumn, with the nadir in late autumn. SC reached mean maximum levels in late summer (31.1 +/- 0.4 cm, p < 0.01), then decreased until the beginning of winter (26.3 +/- 0.4 cm, p < 0.01) and remained low until early spring (27.5 +/- 0.5 cm, p > 0.05) to increase again between mid-spring and the end of the experimental period the following summer (30.7 +/- 0.5 cm, p < 0.01). The mean SC in winter was 16% lower than that in late summer. Semen could be collected from the rams throughout the experiment. Frequencies of sperm head, mid-piece and total abnormalities showed monthly variation (p < 0.05), but tail abnormalities were not affected by month. Low abnormalities were found in autumn (9.4% +/- 2.2%). T was high during autumn (p < 0.01). Minimal T4 concentrations were observed during late summer and early autumn (p < 0.01) when T levels were high. Maximum T4 concentrations were registered in late autumn (p < 0.01); when SC was decreasing; in mid-spring (p < 0.01) one month after shearing and in early summer (p < 0.01). The results suggest that Corriedale rams under Uruguayan extensive management systems show a reproductive seasonality that, in general terms, coincides with photoperiodic variations.

Endothelial cell markers in chronic uremia: relationship with hemostatic defects and severity of renal failure.

Plasma von Willebrand factor antigen, soluble thrombomodulin, and tissue factor were increased in 31 patients with severe chronic renal failure (creatinine clearance <20 ml/min) under conservative treatment, whereas plasminogen activator inhibitor antigen did not differ significantly from healthy controls. No correlation among plasma levels of these proteins was found. Three patterns of relationship between endothelial cell markers and hemostatic defects were identified: 1) Plasma thrombomodulin, a marker of endothelium damage, was found an independent predictor of bleeding time and platelet aggregation, and secretion defects, and was also related to the severity of renal failure; 2) von Willebrand factor antigen, an index of endothelial cell activation and secretion, was significantly correlated with intravascular markers of thrombin and plasmin generation and with platelet adenosine triphosphate content, but not with plasma creatinine levels; and 3) tissue factor and plasminogen activator inhibitor antigen levels were not statistically correlated with the diverse hemostatic defects. Activation of coagulation and fibrinolysis, secondary to endothelial cell activation, appearing early during the evolution of chronic renal failure, is pathogenically related to the platelet dysfunction, and probably to development of atherosclerosis and thrombotic events in this disease. The progression of chronic renal failure, through endothelial cell damage, would lead to aggravation of the platelet functional defect potentiating the hemorrhagic risk.

Hemostatic disorder of uremia: the platelet defect, main determinant of the prolonged bleeding time, is correlated with indices of activation of coagulation and fibrinolysis.

Several parameters of primary hemostasis and markers of activation of coagulation and fibrinolysis were measured in 48 patients with severe (creatinine clearance < 20 ml/min) chronic renal failure (CRF) without dialysis and disease or drugs affecting hemostasis. Bleeding time (BT) was prolonged in 25/48 patients, and was correlated with age of patients, severity of renal failure, hematocrit, impairment in platelet aggregation-secretion and decrease in platelet ATP content. Defects in von Willebrand factor played no role in the prolongation of the BT. Multivariate analysis showed that only platelet dysfunction and severity of renal disease were independent predictors of the BT in uremia. The platelet functional disorder was significantly correlated with a reduction in platelet ATP and ADP. High levels of plasma thrombin-antithrombin complexes (TAT), prothrombin fragment F1 + 2, fibrinogen and factor VIIc were observed in patients with CRF, as described in prethrombotic states. Plasmin-antiplasmin complexes (PAP), fibrinogen and fibrin degradation products (FgDP, FnDP) were significantly increased, and the activity of plasminogen activator inhibitor (PAI-1) was slightly reduced, denoting an activation of fibrinolysis. A negative correlation was found between platelet levels of ATP and ADP with plasma TAT, F1 + 2 and PAP. Furthermore, plasma PAI-1 activity was negatively correlated with the BT and was lower in patients with prolonged BT as compared with controls and patients with normal BT. These links between primary hemostasis and activation of coagulation and fibrinolysis suggest that increased intravascular generation of thrombin and/or plasmin is an important mediator of the defects in primary hemostasis, prolongation of the BT and, probably, bleeding in CRF.

Pharmacokinetics of vancomycin in patients with severely impaired renal function.

The pharmacokinetics of 1 g dose of intravenous vancomycin was studied in 8 patients with severe renal failure. Serum vancomycin levels were determined by fluorescence polarization immunoassay. After single dose of vancomycin peak concentrations ranged from 37.8 microg.ml-1 to 109.3 microg.ml-1 (mean 64.9 +/- 21.7 microg.ml-1). Vancomycin trough concentration 168h after administration of the antibiotic ranged from 2.23 microg.ml-1 to 11.42 microg.ml-1 (mean 6.55 +/- 2.8 microg.ml-1). The data were analyzed using a PCNONLINE computer program, and in all patients a triexponential model described how concentrations decreased in time. Three-compartment parameters obtained from the 8 patients were t1/2 alpha = 0.312 +/- 0.242 h, t1/2 beta 6.012 +/- 5.36 h, and t1/2 gamma = 131.0 +/- 46.7 h. Vd = 0.158 +/- 0.121 1.kg-1, Vdss = 0.920 +/- 0.248 1.kg-1 and total Cl = 0.10 +/- 0.049 1.h-1 per kg of weight. Between 1.5% and 21.2% of the administered vancomycin dose was eliminated during hemodialysis. The dialysis clearance of vancomycin ranged from 50.6 ml.min-1 to 76.8 ml.min-1 (average: 62.4 +/- 10.4 ml.min-1. However, after dialysis plasma concentrations returned to pre-dialysis values. In accordance to our kinetic study 1 g of vancomycin given every 7 days is adequate treatment for methicillin-resistant Staphylococcus aureus infections in patients with severe renal failure whose creatinine clearance is lower than 10 ml.min-1.

Radiopharmacological evaluation in dogs of a new renal function agent.

The hydrophilic penta-anionic complex [Technetium (Carboxymethylisocyanide)6]-5, [Tc(CNCH2COO-)6]-5 (Tc-CAMI) was synthesized to evaluate its potential as a renal function imaging agent. The compound contains six distally arranged carboxyl groups that can act as substrates for the organic acid receptor of the renal cell to effect tubular secretion of this agent. Dynamic gamma-camera imaging of 99mTc-CAMI was performed in normal dogs to compare its bio-distribution and pharmacokinetics with those of proven tubular secretion (99mTc-MAG3) and globular filtration (99mTc-DTPA) agents. The relative difference between the observed mean renal transit times (MRTT) of 99mTc-CAMI and 99mTc-MAG3 was 0.15 compared with 1.24 for 99mTc-CAMI and 99mTc-DTPA. Pathological models of obstructive uropathy, renal arterial stenosis and renal denervation were produced in the same animals to demonstrate the diagnostic potential of the agent. These experiments and data showing that probenecid competes with 99mTc-CAMI for renal transport indicate that this compound functions as a tubular secretion agent and may be useful for monitoring renal function in various disease states.

[Renal and respiratory failure in a pregnant woman with progressive systemic sclerosis. Anatomo-clinical case]. / Insuficiencia renal y respiratoria en una embarazada con esclerosis sistémica progresiva. Caso anatomo-clínico.

Pregnancy in patients with systemic sclerosis may predispose to a fast progression of the disease. We report a woman with systemic sclerosis and multiple visceral involvement that during the third trimester of pregnancy developed a respiratory failure caused by interstitial fibrosis complicated with alveolar hemorrhage, bronchopneumonia and respiratory distress syndrome and a renal failure. On admission, she was subjected to a cesarean section, delivering a 1205 g newborn. In spite of intensive care support, the multisystemic failure became unmanageable and the patient died 15 days after admission. Literature review, although sometimes controversial, indicates that pregnancy is a situation with a definitive death risk for patients with systemic sclerosis, that requires a close follow up.