Músculo liso intrarrenal: histología de una compleja máquina urodinámica / Intrarenal Smooth Muscle: Histology of a Complex Urodymamic Machine

Objetivo: Conocer mejor la disposición microscópica de los haces de músculo liso que hay dentro del parénquima renal humano, su distribución y relaciones anatómicas, intentando hacer una reconstrucción de este sistema muscular. Métodos: Cinco riñones humanos de adultos y un riñón fetal fueron procesados in toto con cortes transversales cada 300 microm. En los cortes histológicos identificamos las fibras musculares lisas, tratando de determinar su inserción, recorrido y relación anatómica con otras estructuras del tejido renal. Resultados: Hay haces de fibras de músculo liso con espesor variable paralelas a los bordes de las pirámides medulares, haces que tratan de rodear la médula en espiral y haces que acompañan a vasos arciformes, siendo estos últimos los más abundantes y fáciles de identificar. Estos grupos de fibras musculares no tienen un sitio de inserción preciso y constante, su periodicidad no es homogénea y no son una extensión directa del músculo de la pelvis renal, aunque algunos haces están en contacto con él. Más inusuales e inconstantes son las pequeñas fibras musculares no asociadas a vasos en la corteza renal y, excepcionalmente, en el intersticio de la médula. Conclusión: Hay un complejo sistema microscópico de fibras musculares lisas que bordean parcialmente la médula y que se relaciona con el músculo de la pelvis renal, sin ser una continuación directa de este. Aunque este pequeño sistema muscular es poco reconocido, podría ser muy importante en urodinamia (AU)

Objective: To know better the microscopic arrangement of the bundles of smooth muscle in the human renal parenchyma, their distribution and anatomical relationships, trying to make a reconstruction of this muscular system. Methods: Five adult human kidneys and one fetal kidney were processed “in toto” with cross sections every 300 micrem. In the histological sections we identify the smooth muscle fibers trying to determine its insertion, course and anatomical relationship with other structures of the kidney tissue. Results: There are bundles of smooth muscle fibers of variable thickness parallel to the edges of the medullary pyramids, bundles that surrounding the medulla in a spiral course, and bundles that accompany arcuate vessels, the latter being the most abundant and easy to identify. These groups of muscle fibers do not have a precise or constant insertion site, their periodicity is not homogeneous and they are not a direct extension of the muscle of the renal pelvis, although some bundles are in contact with it. There are also unusual and inconstant small muscle fibers no associated to vessels in the interstitium of the cortex and, exceptionally, in the medulla. Conclusion: There is a complex microscopic system of smooth muscle fibers that partially surround the renal medulla and are related to renal pelvic muscles without a direct continuity with them. Although this small muscular system is under-recognized, could be very important in urodynamics (AU)

[Intrarenal smooth muscle: histology of a complex urodymamic machine]. / Músculo liso intrarrenal: histología de una compleja máquina urodinámica.

OBJECTIVE: To know better the microscopic arrangement of the bundles of smooth muscle in the human renal parenchyma, their distribution and anatomical relationships, trying to make a reconstruction of this muscular system. METHODS: Five adult human kidneys and one fetal kidney were processed "in toto" with cross sections every 300µm. In the histological sections we identify the smooth muscle fibers trying to determine its insertion, course and anatomical relationship with other structures of the kidney tissue. RESULTS: There are bundles of smooth muscle fibers of variable thickness parallel to the edges of the medullary pyramids, bundles that surrounding the medulla in a spiral course, and bundles that accompany arcuate vessels, the latter being the most abundant and easy to identify. These groups of muscle fibers do not have a precise or constant insertion site, their periodicity is not homogeneous and they are not a direct extension of the muscle of the renal pelvis, although some bundles are in contact with it. There are also unusual and inconstant small muscle fibers no associated to vessels in the interstitium of the cortex and, exceptionally, in the medulla. CONCLUSION: There is a complex microscopic system of smooth muscle fibers that partially surround the renal medulla and are related to renal pelvic muscles without a direct continuity with them. Although this small muscular system is under-recognized, could be very important in urodynamics.

Detección de renina en carcinomas cromófobos de células renales / Detection of renin in chromophobe renal cell carcinomas

Objetivo: Evaluar la expresión de renina en carcinomas cromófobos de células renales y la posible asociación de esta expresión con hipertensión arterial (HTA) sistémica. Material y métodos: Estudio descriptivo retrospectivo. Se incluyeron todos los casos con diagnóstico confirmado de carcinoma cromófobo entre 1990-2004: 31 casos provenientes de 31 pacientes. De los bloques de tejido tumoral incluidos en parafina se hizo inmunohistoquímica para detectar renina usando un anticuerpo monoclonal. De los archivos de historias clínicas obtuvimos información completa con respecto a la presión arterial sistémica antes y después de la resección tumoral. Comparamos frecuencias de HTA en casos con y sin expresión de renina (prueba de Fisher o χ2, según lo adecuado) y evolución de la HTA posresección. Resultados: En 10 de los 31 tumores (32,3%) hubo inmunotinción para renina; esta tinción fue difusa en 6 casos y focal en los 4 restantes. Se detectó HTA en 6 de los 10 pacientes con expresión de renina (60,0%) y en 6 de los 21 pacientes sin expresión de renina (28,6%) (p=0,13). Después de la resección tumoral, ningún paciente con expresión de renina e HTA mostró remisión de la hipertensión. Conclusión: En el carcinoma cromófobo de células renales es frecuente la expresión de renina, pero esta renina parece clínicamente inactiva. Serán necesarios más estudios para conocer las implicaciones en el diagnóstico, la patogénesis y la presentación clínica de esta expresión (AU)

Aim: To evaluate frequency of renin detection in chromophobe renal cell carcinoma, and if this expression was associated to systemic high blood pressure. Material and methods: A descriptive retrospective study. All the cases with confirmed diagnosis of chromophobe carcinoma and resected between 1990 and 2004 were included in our study: 31 cases from 31 patients. Immunohistochemistry was carried out on sections from the paraffin-embedded tissue using a monoclonal antiserum. Patient blood pressure before and after neoplasm resection was registered from clinical histories. We compared frequencies of hypertension in cases with and without expression of renin (Fisher´s text or χ2 as appropriate) and evolution of HTA after tumour resection. Results: We found that 10 of 31 tumors (32.3%) contained immunoreactivity for renin; this staining was diffuse in 6 cases and focal in the other 4. Systemic hypertension was detected in 6 of 10 (60.0%) patients with renin expression and in 6 of 21 (28.6%) patients without renin immunolabeling (p=0.13). After tumor resection none patient with renin expression and high blood pressure showed remission of the hypertension. Conclusion: Renin is frequently expressed in chromophobe renal cell carcinoma, but this renin appears clinically inactive. More studies will be necessary to know implications of this feature on clinical presentation, diagnosis or pathogenesis (AU)

[Detection of renin in chromophobe renal cell carcinomas]. / Detección de renina en carcinomas cromófobos de células renales.

AIM: To evaluate frequency of renin detection in chromophobe renal cell carcinoma, and if this expression was associated to systemic high blood pressure. MATERIAL AND METHODS: A descriptive retrospective study. All the cases with confirmed diagnosis of chromophobe carcinoma and resected between 1990 and 2004 were included in our study: 31 cases from 31 patients. Immunohistochemistry was carried out on sections from the paraffin-embedded tissue using a monoclonal antiserum. Patient blood pressure before and after neoplasm resection was registered from clinical histories. We compared frequencies of hypertension in cases with and without expression of renin (Fisher's text or chi(2) as appropriate) and evolution of HTA after tumour resection. RESULTS: We found that 10 of 31 tumors (32.3%) contained immunoreactivity for renin; this staining was diffuse in 6 cases and focal in the other 4. Systemic hypertension was detected in 6 of 10 (60.0%) patients with renin expression and in 6 of 21 (28.6%) patients without renin immunolabeling (p=0.13). After tumor resection none patient with renin expression and high blood pressure showed remission of the hypertension. CONCLUSION: Renin is frequently expressed in chromophobe renal cell carcinoma, but this renin appears clinically inactive. More studies will be necessary to know implications of this feature on clinical presentation, diagnosis or pathogenesis.

C4D immunostaining in surveillance endomyocardial biopsies from well-functioning heart allografts.

OBJECTIVE: The meaning of biopsy C4d detection in heart allografts without dysfunction or morphologic changes suggesting antibody-mediated rejection (AMR) is not clear. The aim of this study was to search for an association between C4d detection in allograft biopsies of well-functioning hearts without changes suggestive of AMR, and clinical outcomes. METHODS: Endomyocardial protocol biopsies from 44 heart transplant patients with well-functioning grafts and without changes suggesting AMR were performed at 1 month and 1 year after transplantation and analyze the presence of C4d deposition using immunohistochemistry. Two-year follow-up was based on clinical parameters and echocardiographic information. Heart graft function was categorized as good vs. poor. The presence of C4d, using diverse schemes to graduate the extension of the deposition, was correlated with clinical graft outcomes. RESULTS: C4d deposition was observed in the capillary walls of 33 biopsies (37.5%; n = 25 patients; 56.8%). No biopsy had diffuse (>50%) immunostaining. Six patients presented with multifocal capillary C4d immunostaining in at least 1 biopsy. Capillary positivity for C4d (if focal or multifocal) showed no statistical association with cellular rejection or graft function. Perimyocytic C4d detection was neither associated with rejection nor graft outcome. CONCLUSION: Our work failed to demonstrate an association between C4d detection in protocol biopsies of heart grafts and clinical outcomes. The clinical utility of C4d staining in solid organ transplantation may vary by organ. Our results suggest that C4d did not have clinical utility in surveillance biopsies of well-functioning heart grafts without morphological changes suggesting AMR.

[Expression of nephrin, podocin and a-actinine-4 in renal tissue of patients with proteinuria]. / Expresión de nefrina, podocina y alpha-actinina-4 en tejido renal de pacientes con proteinuria.

INTRODUCTION: Slit diaphragm and/or podocyte's cytoskeleton alterations are related to proteinuria and nephrotic syndrome. In our population, focal and segmental glomerulosclerosis causing nephrotic syndrome is the more frequent biopsy demonstrated glomerulopathy. Our aim was search for alterations in some slit diaphragm-associated proteins in patients with nephrotic range proteinuria. METHODS: Renal tissue from 40 patients with nephrotic range proteinuria, 10 patients with non-nephrotic proteinuria, 3 with isolated hematuria, and 10 samples of normal renal tissue (deceased donors) were studied, by indirect immunofluorescence, for expression of nephrin, podocin, and alpha-actinin-4. RESULTS: Expression of these proteins was lineal, homogeneous, in the glomerular capillary walls in normal renal tissue and in patients with isolated hematuria. In nephrotic proteinuria this normal appearance was altered and immunostaining showed a fine granular appearance. In 18 cases (45%) of patients with nephrotic proteinuria and 3 cases (30%) of patients with non-nephrotic proteinuria there was loss of at least one of these proteins (p = 0.49). These alterations were found in the diverse glomerulopathies more frequently causing nephrotic syndrome. CONCLUSIONS: In nephrotic range proteinuria redistribution or loss of expression of slit diaphragm-associated proteins is very frequent. In many of our cases this fact could be more a consequence than a cause of proteinuria. These alterations can be also evidenced in patients with non-nephrotic proteinuria.

[Ureterostomy cytomegalovirus infection presenting as stoma ulceration in a kidney allograft receptor: a case report]. / Ureteritis por citomegalovirus en receptor de trasplante renal. Informe de un caso con presentación inusual.

Cytomegalovirus (CMV) is the most common viral infection affecting transplant patients, but urinary tract involvement has been rare. Only a few cases of symptomatic ureteritis have been reported in renal transplant recipients. In previous reports the presentation of CMV ureteritis is obstructive nephropathy, often in the absence of systemic illness, or rarely it may also mimic allograft rejection with minimal obstructive symptoms. We describe an additional case of CMV ureteritis in a patient with cutaneous ureterostomy. The unusual clinical presentation with urinary infection symptoms and ureterostomy stoma ulceration constitute a very particular presentation. The increasing report cases with CMV ureteritis suggest an increase of this post-transplant complication.

Ureteritis por citomegalovirus en receptor de trasplante renal. Informe de un caso con presentación inusual / Ureterostomy cytomegalovirus infection presenting as stoma ulceration in a kidney allograft receptor: a case report

La infección por citomegalovirus (CMV) es la infección viral más frecuente en pacientes trasplantados, pero es muy inusual el compromiso del tracto urinario. Sólo se han informado unos pocos casos de uretritis por CMV en trasplantados renales. En los informes previos la presentación clínica más habitual es nefropatía obstructiva, a menudo en ausencia de enfermedad sistémica, o, algunas veces, puede simular un episodio de rechazo con mínimos síntomas obstructivos. Nosotros describimos un caso más de uretritis por CMV en un paciente trasplantado renal con ureterostomía y una presentación muy inusual caracterizada por síntomas de infección de vías urinarias y ulceración en la boca de la ureterostomía. El número incrementado de informes de ureteritis por CMV en trasplantados renales plantea la posibilidad de un aumento en la incidencia de esta complicación post-trasplante (AU)

Cytomegalovirus (CMV) is the most common viral infection affecting transplant patients, but urinary tract involvement has been rare. Only a few cases of symptomatic ureteritis have been reported in renal transplant recipients. In previous reports the presentation of CMV ureteritis is obstructive nephropathy, often in the absence of systemic illness, or rarely it may also mimic allograft rejection with minimal obstructive symptoms. We describe an additional case of CMV ureteritis in a patient with cutaneous ureterostomy. The unusual clinical presentation with urinary infection symptoms and ureterostomy stoma ulceration constitute a very particular presentation. The increasing report cases with CMV ureteritis suggest an increase of this post-transplant complication (AU)

[Ancillary studies in the differential diagnosis of epithelial renal cell tumors with granular cells]. / Estudios auxiliares en el diagnóstico diferencial de tumores epiteliales renales con células granulares.

INTRODUCTION AND OBJECTIVES: Differential diagnosis of renal neoplasms with granular cells may pose difficulties and implications on ontogeny and prognosis. Our aims are to characterize the pattern of immunostaining and to search for a useful diagnosis panel. METHODS: We studied with colloidal iron staining (Mowry's modified method) and 22 commonly used immunomarkers 22 conventional carcinomas (CC), 37 chromophobe carcinomas (CPC), 8 oncocytomas (OC), and 7 collecting duct carcinomas (CDC) with granular cells. Cases with not entirely clear diagnosis were excluded. RESULTS: Colloidal iron staining was diffuse, strong, reticular, and cytoplasmic in 32 CPC cases, the diffuse and strong pattern was not observed in other tumors. The more useful diagnostic panel was cytokeratin 7 (CK7)/CD10/vimentine (vim). The 8 OC were negative for the three antibodies. The most common profile for CC was CK7-/CD10+/vim+, the CPC profile was CK7+/CD10-/vim-, and CDC did not show a particular profile. With these three antibodies specificity was >90% for the differential diagnosis. Adding colloidal iron staining specificity was 100%. CONCLUSIONS: Morphologic features, colloidal iron staining (modified Mowry's method), and immunostaining with CK7/CD10/vim permit the final diagnosis with high specificity. However, a 100% specific marker does not exist at the present time.

Estudios auxiliares en el diagnóstico diferencial de tumores epiteliales renales con células granulares / Ancillary studies in the differentital diagnosis of epithelial renal cell tumors with granular cells

Introducción y objetivos: El diagnóstico diferencial de neoplasias renales con células granulares puede tener dificultades e implicaciones en la ontogenia y el pronóstico. Nuestro propósito es caracterizar el patrón de inmunotinción y buscar un mejor panel de inmunohistoquímica (IHQ) útil en su diagnóstico diferencial. Métodos: Estudiamos con hierro coloidal (método de Mowry modificado) y 22 inmunomarcadores de uso común 22 carcinomas convencionales (CC), 37 carcinomas cromófobos (CPC), 8 oncocitomas (OC) y 7 carcinomas de conductos colectores (CDC) con células granulares. Los casos sin diagnóstico completamente claro fueron excluidos. Resultados: La tinción con hierro coloidal fue citoplasmática, difusa, fuerte y reticular en 32 de los 37 CPC. El patrón difuso y fuerte no fue observado en ninguno de los otros tumores. El panel diagnóstico más útil fue citoqueratina 7(CK7)/CD10/vimentina (vim). Todos los OC fueron negativos para los 3 anticuerpos. El perfil más común para CC fueCK7-/CD10+/vim+ y el perfil para CPC fue CK7+/CD10-/vim-. Los CDC no mostraron un perfil particular. Con estos tres marcadores encontramos una especificidad mayor del 90% para el diagnóstico diferencial. Si adicionamos el hierro coloidal la especificidad fue del 100%.Conclusiones: Los rasgos morfológicos, la tinción con hierro coloidal con el método de Mowry modificado y la inmunomarcación con CK7/CD10/vim permite el diagnóstico final con alta especificidad. Sin embargo, actualmente no existe un marcador o panel 100% sensible y específico (AU)

Introduction and objectives: Differential diagnosis of renal neoplasms with granular cells may pose difficulties and implications on ontogeny and prognosis. Our aims are to characterize the pattern of immunostaining and to search fora useful diagnosis panel. Methods: We studied with colloidal iron staining (Mowry`s modified method) and 22 commonly used immunomarkers 22 conventional carcinomas (CC), 37 chromophobe carcinomas (CPC), 8 oncocytomas (OC), and 7 collecting duct carcinomas (CDC) with granular cells. Cases with not entirely clear diagnosis were excluded. Results: Colloidal iron staining was diffuse, strong, reticular, and cytoplasmic in 32 CPC cases, the diffuse and strong pattern was not observed in other tumors. The more useful diagnostic panel was cytokeratin 7 (CK7)/CD10/vimentine (vim). The 8 OC were negative for the three antibodies. The most common profile for CC was CK7-/CD10+/vim+, the CPC profile was CK7+/CD10-/vim-, and CDC did not show a particular profile. With these three antibodies specificity was>90% for the differential diagnosis. Adding colloidal iron staining specificity was 100%.Conclusions: Morphologic features, colloidal iron staining (modified Mowry’s method), and immunostaining withCK7/CD10/vim permit the final diagnosis with high specificity. However, a 100% specific marker does not exist at the present time (AU)

Histologic assessment of donor kidneys and graft outcome: multivariate analyses.

UNLABELLED: We performed a multivariate analysis to evaluate the importance of histologic parameters in donor kidney biopsies as predictors of graft outcome. METHODS: Wedge protocol biopsies from a single center were analyzed for glomerulosclerosis (GS), interstitial fibrosis (IF), tubular atrophy (TA), arteriosclerosis (AS), and arteriolar hyalinosis (AH). Alterations were quantified as percentage (GS, IF) or semiquantified according to Banff criteria (IF, TA, AS, AH). We calculated creatinine clearance (CrCl) at 1, 2, and 3 years posttransplant. Donor data included age, gender, and type: non-heart-beating donor or brain dead donors. Recipient data included age, gender, cold ischemia time, number of HLA mismatches, peak level of the panel reactive antibody (PRA), number of acute rejection episodes (ARE), and presence or absence of cytomegalovirus (CMV) disease. Univariate and multivariate analyses were performed. Follow-up range was 1 to 4.2 years. RESULTS: GS, IF, TA, and AH were associated with graft survival in the multivariate analysis. The histologic parameters were associated with CrCl at several posttransplant time intervals, but the significance of association was lost in the multivariate analysis. Donor age showed a better correlation with graft function. In the univariate analyses adjusting for donor age, only IF and AH were associated with graft function. CONCLUSIONS: Histologic parameters showed a modest association with graft function. In our study, donor age is the better predictor of graft function. IF and AH may be similar to or better than GS as predictors of graft outcome.

[Immunohistochemical profile and clinical features of mucinous tubular and spindle renal cell carcinoma]. / Caracteristicas inmunofenotipicas y clinicas del carcinoma renal mucinoso tubular y de células fusiformes.

INTRODUCTION: We present the immunohistochemical (IHC) analyses of a series of four kidney tumors currently classified as mucinous tubular and spindle renal cell carcinoma (WHO), a tumor with uncertain histogenesis and differentiation. Our aims were to determine an immunoprofile and to add clinical and morphological information about this rare renal carcinoma. MATERIAL AND METHODS: The four tumors were found between 415 renal carcinomas at our center (0.89%). IHC was carried out with a panel of antibodies in these four cases. Morphogical and clinical information was collected and analyzed. RESULTS: All tumors were well circumscribed and confined to the kidney. Immunoreactivity for cytokeratin (CK)7 was intense and diffuse. Immunostaining was variable for EMA, vimentin, S-100, Ulex europaeus antigen, high-molecular-weight CK, CK 8, CK18, and CK 19. The tumors were homogeneously negative for CEA, CD15, CD10, CD34, desmin, actin, CK10, CK20, and HMB45. Proliferative index (Ki67) was <1% en all cases. The immunoreactivity was similar in cuboidal and spindle cells. CONCLUSIONS: The present tumor shows a variable immunophenotype and there is not a precise cell type differentiation. The immunostaining in cuboidal and spindle cells suggests a similar differentiation and histogenesis.

Características inmunofenotípicas y clínicas del carcinoma renal mucinoso tubular y de células fusiformes / Immunohistochemical profile and clinical features of mucinous tubular and spindle renal cell carcinoma

Introducción: El carcinoma renal mucinoso y tubular de células fusiformes es una neoplasia recientemente incluida en la clasificación de tumores renales. Aún desconocemos aspectos moleculares y de su evolución. Nuestros objetivos son describir características inmunofenotípicas del tumor y aportar casos adicionales para un mejor conocimiento de la neoplasia. Material y métodos: Realizamos inmunohistoquímica con un amplio panel de anticuerpos a 4 tumores (0,89% de carcinomas renales en nuestro centro). Correlacionamos con hallazgos clínicos y tratamos de determinar patrones de inmunotinción. Resultados: Todos los casos marcaron intensa y difusamente para citoqueratina (CK)7. La inmunotinción fue variable para antígeno de membrana epitelial, vimentina, S-100, antígeno Ulex europaeus, CK de alto peso molecular, CK8, CK18 y CK19. Los tumores fueron homogéneamente negativos para antígeno carcinoembriónico, CD15, CD10, CD34, desmina, actina, CK10, CK20 y HMB45. El índice proliferativo (Ki67) fue menor del 1% en todos los casos. La marcación fue similar en células cúbicas y fusiformes. Conclusiones: Este tumor presenta un inmunofenotipo variable de acuerdo con diferentes trabajos y no se conoce con precisión su histogénesis o la célula hacia la cual se diferencian. La similitud en la expresión de marcadores en células cúbicas y fusiformes confirma un mismo origen y diferenciación

Introduction: We present the immunohistochemical (IHC) analyses of a series of four kidney tumors currently classified as mucinous tubular and spindle renal cell carcinoma (WHO), a tumor with uncertain histogenesis and differentiation. Our aims were to determine an immunoprofile and to add clinical and morphological information about this rare renal carcinoma. Material and methods: The four tumors were found between 415 renal carcinomas at our center (0.89%). IHC was carried out with a panel of antibodies in these four cases. Morphogical and clinical information was collected and analyzed. Results: All tumors were well circumscribed and confined to the kidney. Immunoreactivity for cytokeratin (CK)7 was intense and diffuse. Immunostaining was variable for EMA, vimentin, S-100, Ulex europaeus antigen, high-molecular-weight CK, CK 8, CK18, and CK 19. The tumors were homogeneously negative for CEA, CD15, CD10, CD34, desmin, actin, CK10, CK20, and HMB45. Proliferative index (Ki67) was <1% en all cases. The immunoreactivity was similar in cuboidal and spindle cells. Conclusions: The present tumor shows a variable immunophenotype and there is not a precise cell type differentiation. The immunostaining in cuboidal and spindle cells suggests a similar differentiation and histogenesis

The perfusion pressure in non-heart-beating donors may expand the glomeruli.

INTRODUCTION: We have observed expanded glomeruli in biopsies of kidneys from non-heart-beating donors (NHBDs). We sought to determine the differences in glomerular size between NHBDs and brain-dead donors and to assess whether glomerular size impacted graft outcome. METHODS: We estimated the glomerular area using the maximal planar area (MPA) method in 198 pretransplant biopsies from 119 donors: 54 (45.4%) NHBDs and 65 (54.6%) brain-dead donors. Donor data and graft outcomes were correlated with MPA and percentage of glomerulosclerosis. The range of follow-up was 1 to 3 years. Uni- and multivariate analyses were performed. RESULTS: MPA was larger among NHBDs. MPA and GS both significantly correlated with donor age. The association between MPA and age was independent of nephron loss (ie; GS). Increased glomerular size was only observed among donors younger than 50 years. Graft survival and function were not independently associated with MPA. Donor age was a better predictor of graft outcome. CONCLUSIONS: The perfusion pressure used in NHBDs may expand the glomeruli, but this maneuver does not have any effect on graft outcome. Among donors without severe changes, glomerular size increment shows a limit around the sixth decade of life. In our study, MPA was not an independent predictor of graft survival or function.

Detection of amastigotes of Trypanosoma cruzi in a kidney graft with acute dysfunction.

We described a case of allograft kidney dysfunction associated with renal parenchymal infection with amastigotes of Trypanosoma cruzi. The patient was diagnosed as being chronically infected prior to transplantation. The infection was probably acquired by blood transfusion. He could not complete antiparasitic treatment due to drug toxicity. He was transplanted from a cadaver who showed a negative test for Chagas' disease. One year after transplantation the serum creatinine progressively increased. Histological examination of renal biopsy revealed intracytoplasmic amastigotes of T cruzi. No evidence of other specific alterations in the graft was detected. It was unknown whether graft dysfunction was only due to parasitic infection. The present case confirmed that T cruzi can infect kidney grafts and that immunosuppression in kidney transplantation is potentially a cause of dissemination of Chagas' disease.

[BK virus in kidney allografts: a search for histologic evidence of the infection]. / Virus BK en injertos renales: evidencia histológica de la infección.

BACKGROUND: BK virus (BKV) associated interstitial nephritis is a complication in renal transplantation recipients. Its incidence is controversial. The aim of the present study is to determine the incidence of histopathologic evidence of BKV-infection in a single centre. MATERIALS AND METHODS: Renal allograft tissue samples (n = 838) from 526 patients undergoing renal transplant were evaluated by light microscopy. Polymerase chain reaction (PCR) assay for BKV DNA was performed in 41 microdissected cell populations from cases with viral inclusions, cases with other nuclear changes, and cases without nuclear changes. RESULTS: Polyomavirus-inclusions were identified in six cases (five with interstitial nephritis and other one with only urothelial infection). In one case with interstitial nephritis the DNA was degraded. PCR confirmed BKV infection in the other five and was negative in cases without inclusions. CONCLUSIONS: Five patterns of inclusions bodies are observed and they appear to be characteristic. PCR assay seemingly have a high specificity for BKV detection and it does not usually detect latent viral infection.

[Familial focal and segmentary hyalinosis]. / Hialinosis focal y segmentaria familiar.

Focal segmental glomerulosclerosis represents a finding in several renal disorders, characterized by proteinuria and sometimes by arterial hypertension and progressive decline in renal function. There are primary (idiopathic and familial) and secundary forms. In the last 20 years several familial cases has been reported, with a great genetic heterogeneity (dominant and recessive forms) and with multiple associations with particular MHC class-I and class-II gene loci, being Al, DR3 o DR7 the most frequently reported. We described three members of same family with focal segmental hyalinosis that shared the HLA haplotype A31 B61 DR13. This association has not been described previously. We highlight that genetic and acquired factors (obesity, hypertension...) could have importance in the development of progressive renal failure in these patients.

Hialinosis focal y segmentaria familiar / A family with focal segmental glomerulosclerosis

Las glomerulonefritis con hialinosis focal y segmentaria son la expresión morfológica de varias entidades clínicas de diversa etiología. Sus manifestaciones clínicas son también muy inespecíficas: proteinuria con o sin síndrome nefrótico y en algunos casos hipertensión arterial e insuficiencia renal progresiva. Existen formas primarias (idiopáticas o familiares) y secundarias. En los últimos 20 años se han comunicado varios casos familiares, con una gran heterogeneidad genética (formas dominantes y recesivas) habiéndose postulado asociaciones con determinados antígenos del complejo de histocompatibilidad mayor (MHC) clase I y II, siendo Al, DR3 o DR7 los más frecuentes. Describimos la aparición de hialinosis focal y segmentaria en tres miembros de una familia que comparten A31 B61 DR13, asociación no descrita. Resaltamos que la combinación de factores genéticos y adquiridos (obesidad, hipertensión) pueden ser importantes en el desarrollo de insuficiencia renal progresiva en estos enfermos

Focal segmental glomerulosclerosis represents a finding in several renal disorders, characterized by proteinuria and sometimes by arterial hypertension and progressive decline in renal function. There are primary (idiophatic and familial) and secundary forms. In the last 20 years several familial cases has been reported, with a great genetic heterogeneity (dominant and recessive forms) and with multiple associations with particular MHC class-I and class-II gene loci, being Al, DR3 o DR7 the most frecuently reported. We described three members of same family with focal segmental hyalinosis that shared the HLA haplotype A31 B61 DR13. This association has not been described previously. We highlight that genetic and acquired factors (obesity, hypertension…) could have importance in the development of progressive renal failure in these patients

Brain granulomas in neurocysticercosis patients are associated with a Th1 and Th2 profile.

Neurocysticercosis (NCC) is a common central nervous system (CNS) infection caused by Taenia solium metacestodes. Despite the well-documented importance of the granulomatous response in the pathogenesis of this infection, there is limited information about the types of cells and cytokines involved. In fact, there has been limited characterization of human brain granulomas with any infectious agent. In the present study a detailed histological and immunohistochemical analysis of the immune response was performed on eight craniotomy specimens where a granuloma surrounded each T. solium metacestode. The results indicated that in all the specimens there was a dying parasite surrounded by a mature granuloma with associated fibrosis, angiogenesis, and an inflammatory infiltrate. The most abundant cell types were plasma cells, B and T lymphocytes, macrophages, and mast cells. Th1 cytokines were prevalent and included gamma interferon, interleukin-18 (IL-18), and the immunosuppressive, fibrosis-promoting cytokine transforming growth factor beta. The Th2 cytokines IL-4, IL-13, and IL-10 were also present. These observations indicate that a chronic immune response is elicited in the CNS environment with multiple cell types that together secrete inflammatory and anti-inflammatory cytokines. In addition, both collagen type I and type III deposits were evident and could contribute to irreversible nervous tissue damage in NCC patients.