Renal biopsy in diabetic patients: clinical indicators and pathological findings / Biopsia renal en pacientes diabéticos: indicadores clínicos y hallazgos patológicos

ABSTRACT Background: In addition to diabetic nephropathies (DNP), prevalence of nondiabetic nephropathies (NDNP) is also known to be frequent in patients diagnosed with type 2 Diabetes mellitus (DM). Early diagnosis of these conditions is important for the treatment and prognosis of these patients. Aim: This study aimed to investigate the relationships between clinical and laboratory findings of type 2 diabetic patients' renal biopsies. Material and Methods: We retrospectively reviewed the medical records of 140 patients who had diagnosis of type 2 DM and underwent renal biopsy from July 2020- August 2022 at nephrology clinics of Hospital Umraniye. Renal biopsy results, presence of hypertension, diabetic retinopathy, hematuria, proteinuria; duration of the disease, biopsy indications, glycated hemoglobin (HbA1c), serum creatinine, blood urea nitrogen, albumin, and proteinuria levels in 24h urine were measured. The statistical significance level was determined as p<0,05. Results: NDNP were detected in 43,7% of the patients. Among these the most common diagnosis was interstitial nephritis (20%). The most common biopsy indication was found to be nephrotic range proteinuria (30,7%). The difference between the DNP and NDNP patients' renal biopsy indications was statistically significant (p<0,001). DNP patients had a higher retinopathy incidence (60%,11%, p<0,001). A statistically significant difference was detected between the disease duration of DNP and NDNP groups (11,23 +5,74 years, p:0,002). According to multivariate regression analysis DR and HbA1c value, more than 7% have 4, 482 and 4,591-fold increased the risk of DNP incidence (p=0,021, p:0,024). Conclusion: Early diagnosis of DNP and NDNP of diabetic patients by performing renal biopsies affects the treatment and prognosis of the patients. Therefore, when evaluating diabetic patients, its necessary not to overlook the findings suggestive of NDNP.

RESUMEN Antecedentes: Además de las nefropatías diabéticas (DNP), también se conoce la prevalencia frecuente de nefropatías no diabéticas (NDNP) en pacientes diagnosticados con Diabetes mellitus tipo 2 (DM). El diagnóstico precoz de estas condiciones es importante para el tratamiento y pronóstico de estos pacientes. Objetivo: Este estudio tuvo como objetivo investigar las relaciones entre los hallazgos clínicos y de laboratorio de las biopsias renales de pacientes diabéticos tipo 2. Material y Métodos: Revisamos retrospectivamente las historias clínicas de 140 pacientes que tenían diagnóstico de DM tipo 2, desde julio de 2020 hasta agosto de 2022, y se les realizó biopsia renal en las clínicas de nefrología del Hospital Umraniye. Se revisaron los resultados de biopsia renal, presencia de hipertensión arterial, retinopatía diabética, hematuria y proteinuria así como también la duración de la enfermedad, las indicaciones de la biopsia, la hemoglobina glucosilada (HbA1c), la creatinina sérica, el nitrógeno ureico en sangre, la albúmina y los niveles de proteinuria en orina de 24 h. El nivel de significación estadística se determinó como p<0,05. Resultados: se detectaron NDNP en el 43,7% de los pacientes. Entre estos, el diagnóstico más común fue la nefritis intersticial (20%). La indicación de biopsia más frecuente resultó ser la proteinuria en rango nefrótico (30,7%). La diferencia entre las indicaciones de biopsia renal de los pacientes DNP y NDNP fue estadísticamente significativa (p<0,001). Los pacientes con DNP tuvieron una mayor incidencia de retinopatía (60%, 11%, p<0,001). Se detectó una diferencia estadísticamente significativa entre la duración de la enfermedad de los grupos DNP y NDNP (11,23 +5,74 años, p:0,002). De acuerdo con el análisis de regresión multivariado, la presencia de DR y el valor de HbA1c en más del 7% tienen 4,482 y 4,591 veces mayor riesgo de incidencia de DNP (p = 0,021, p: 0,024). Conclusión: El diagnóstico precoz de DNP y NDNP de pacientes diabéticos mediante la realización de biopsias renales afecta el tratamiento y pronóstico de los pacientes. Por lo tanto, al evaluar pacientes diabéticos, es necesario no pasar por alto los hallazgos sugestivos de NDNP.

Patrones morfológicos de la enfermedad glomerular en México: Reporte de un centro de referencia en nefropatología / Morphological patterns of glomerular disease in Mexico: Report of a reference center in nephropathology

RESUMEN Introducción: En México, la enfermedad renal crónica (ERC) representa un gran problema de salud y las glomerulopatías (GP) representan la tercera causa de ERC. Objetivo: Describir, desde una base de datos de biopsias renales (BR) nativas, los diferentes patrones morfológicos de GP en México. Métodos: Se analizaron registros de BR de riñón nativo en un centro de referencia en nefropatología, todas las BR fueron evaluadas por una única nefropatóloga (AVP). El diagnóstico final en cada caso se basó en parámetros clínicos e histopatológicos. Resultados: Fueron revisadas 2084 BR, con edad de 34.4 ± 17.6 años. 1085 BR (52.1%) en género femenino; el síndrome nefrótico fue más frecuente en hombres (p<0.001) y síndrome nefrítico fue más frecuente en mujeres (p<0.001). GP primarias y nefropatías túbulo-intersticiales fueron más diagnosticadas en hombres (p<0.01). Nefritis lúpica (NL) fue la GP secundaria más reportada. La glomeruloesclerosis focal y segmentaria (GEFS) fue la GP primaria diagnosticada con mayor frecuencia en ambos géneros. Vasculitis por inmunoglobulina A fue la enfermedad vascular más frecuentemente detectada. Síndrome nefrótico fue la indicación más frecuente de BR (42.9%), seguido de: síndrome nefrítico (23.9%), proteinuria aislada (16.4%), daño renal agudo (8.7%), alteraciones urinarias asintomáticas (6.2%) y ERC (1.8%). Conclusiones: La GP primarias con mayor frecuencia fueron GEFS. Las GP secundarias más frecuentemente reportadas fueron NL, predominantemente en mujeres. Se observó nefropatía IgA con mayor frecuencia en comparación con otras series publicadas en México. Hubo diferencias significativas en la presentación de GP en relación con el género y la edad del paciente.

ABSTRACT Introduction: In Mexico, chronic kidney disease (CKD) represents a major health problem, and glomerulopathies (GP) represent the third leading cause of CKD. Aim: From a database of native kidney biopsies (KB), describe the different morphological patterns of GP in Mexico. Methods: Records of native KB in a nephropathology referral center were evaluated by a single nephropathologist. The final diagnosis in each case was based on clinical parameters and histopathological findings. Results: 2084 KB were analyzed, patients were 34.4±17.6 years of age, there were 1085 KB (52.1%) in females; nephrotic syndrome was most frequent in males (p<0.001), and nephritic syndrome was more frequent in females (p <0.001). Primary GP and túbulo-interstitial diseases were most diagnosed in males (p <0.01). Lupus nephritis (LN) was the most-reported secondary GP. Focal and segmental glomerulosclerosis (FSGS) was the primary GP most often diagnosed in both genders. The most frequently detected vascular disease was immunoglobulin A vasculitis. Nephrotic syndrome was the most frequent indication for KB (42.9%), followed by: nephritic syndrome (23.9%), isolated proteinuria (16.4%), acute kidney injury (8.7%), asymptomatic urinary alterations (6.2%), and CKD (1.8%). Conclusions: The most frequently observed primary GP was FSGS, and LN was the most frequent secondary GP, predominantly in females, and IgA nephropathy was observed more frequently in comparison with other series published in Mexico. There were significant differences in GP presentation in relation to patient sex and age.

No effect of desmopressin administration before kidney biopsy on the risk of major post-biopsy bleeding.

BACKGROUND/AIMS: The most important complication of kidney biopsy is bleeding, and it is unclear whether desmopressin is effective in preventing it. Thus, the study was conducted to compare post-biopsy bleeding with or without desmopressin prescription prior to percutaneous kidney biopsy. METHODS: In this single-centered, retrospective, and observational study, 3,018 adult patients who underwent kidney biopsy between January 1, 2003 and March 31, 2019 at our institute were recruited. Of these, 776 patients received desmopressin. To compare the differences in major bleeding events between patients administered and not administered with desmopressin, propensity score matching was performed. RESULTS: Before propensity score (PS) matching, it was observed that patients in the desmopressin group were significantly older (p<0.001) and had a higher blood pressure (p<0.001), higher serum creatinine (p<0.001), lower hemoglobin levels (p<0.001), and lower platelet counts (p=0.001) than those in the no-desmopressin group. Furthermore, the incidence of renal artery embolization was not significantly different between the two groups (p=0.077); however, blood transfusions occurred significantly more frequently in the desmopressin group (p<0.001). A comparison of the two groups after PS matching did not reveal any differences in the incidence of renal artery embolization (p=0.341), blood transfusion (p=0.579), and total major bleeding events (p=0.442). Furthermore, there was no difference in the incidence of perinephric hematoma on computed tomography or ultrasound (p=0.120). CONCLUSIONS: We do not recommend desmopressin administration before kidney biopsy.

Glomerulonefritis rápidamente progresiva secundaria a vasculitis pauciinmune, entidad poco frecuente: caso clínico y revisión de la literatura

Introducción las vasculitis asociadas a anticuerpos anticitoplasma de neutrófilos (ANCA) son un grupo heterogéneo de patologías, caracterizadas por la inflamación y la destrucción de vasos sanguíneos de pequeño y mediano calibre, asociados a la presencia de ANCA circulantes. Se presentan con una amplia variedad de signos y síntomas y, si no se tratan, conllevan a una alta morbimortalidad. Estos constituyen una causa poco frecuente de glomerulonefritis rápidamente progresiva y lesión renal aguda con necesidad de soporte renal, por lo que se requiere un alto índice de sospecha en el abordaje inicial. Objetivo con el presente artículo se busca sensibilizar al personal médico sobre la necesidad de una búsqueda activa de vasculitis como causa de glomerulonefritis y el impacto del diagnóstico y tratamiento tempranos en la condición clínica del paciente. Presentación del caso paciente masculino de 65 años atendido en un centro hospitalario de referencia en la ciudad de Pereira, Risaralda, quien debuta con glomerulonefritis rápidamente progresiva secundaria a poliangeítis microscópica en su posoperatorio de prostatectomía, y que progresa a lesión renal aguda con necesidad de inicio de soporte renal de tipo hemodiálisis intermitente; posterior a realizar biopsia renal y perfil de autoinmunidad, se confirma el diagnóstico de vasculitis tipo poliangeítis microscópica, se inicia manejo específico inmunosupresor, con lo que se logra la remisión de la enfermedad y con ello una mejoría en la función renal que permite suspender la terapia de reemplazo renal. Actualmente el paciente permanece asintomático, con remisión de su enfermedad con manejo inmunosupresor, asistiendo a controles ambulatorios con Nefrología sin mención de complicaciones secundarias a terapia farmacológica. Discusión y conclusión En las vasculitis asociadas a los anticuerpos anticitoplasma de neutrólos (ANCA), el diagnóstico oportuno y el establecimiento de una terapia inmunomoduladora adecuada son el pilar fundamental en el abordaje de esta entidad. Un diagnóstico tardío está directamente relacionado con un pobre pronóstico a corto plazo. El diagnóstico oportuno requiere de un índice de sospecha apropiado

Introduction Vasculitis associated with antineutrophil cytoplasmic antibodies (ANCA) are a heterogeneous group of pathologies; characterized by the inflammation and destruction of small and medium caliber blood vessels associated with the presence of circulating ANCA. They present with a wide variety of signs and symptoms and, if left untreated, lead to high morbidity and mortality; They are a rare cause of rapidly progressive glomerulonephritis and acute kidney injury requiring renal support, which is why a high index of suspicion is required in the initial approach. Purpose This article seeks to sensitize the medical personnel for the need of an active search for vasculitis as a cause of glomerulonephritis and the impact of early diagnosis and treatment in the patient's clinical condition. Case presentation We report the case of a 65-year-old male patient treated in a reference hospital in the city of Pereira, Risaralda, who debuted with rapidly progressive glomerulonephritis secondary to microscopic polyangiitis in his postoperative period of a prostatectomy, progressing to acute kidney injury needing to start renal support such as intermittent hemodialysis; after performing a renal biopsy and autoimmunity profile, the diagnosis of microscopic polyangiitis-type vasculitis is confirmed, specific immunosuppressive management is initiated, which achieves remission of the disease and with it an improvement in renal function that allows the suspension of renal replacement therapy, y, currently a patient He remains asymptomatic, with remission, with immunosuppressive management, attending outpatient controls with nephrology without mention of complications secondary to pharmacological therapy. Discussion and conclusion In antineutrophil cytoplasmic antibody(ANCA)-Associated Vasculitis , timely diagnosis and the establishment of adequate immunomodulatory therapy are the fundamental pillars in the approach to this entity. A late diagnosis is directly related to a poor short-term prognosis. Timely diagnosis requires an appropriate index of suspicion.

No effect of desmopressin administration before kidney biopsy on the risk of major post-biopsy bleeding / Ausencia de efecto de la administración de desmopresina antes de una biopsia renal sobre el riesgo de hemorragia mayor tras la biopsia

Background/Aims: The most important complication of kidney biopsy is bleeding, and it is unclear whether desmopressin is effective in preventing it. Thus, the study was conducted to compare post-biopsy bleeding with or without desmopressin prescription prior to percutaneous kidney biopsy.MethodsIn this single-centered, retrospective, and observational study, 3,018 adult patients who underwent kidney biopsy between January 1, 2003 and March 31, 2019 at our institute were recruited. Of these, 776 patients received desmopressin. To compare the differences in major bleeding events between patients administered and not administered with desmopressin, propensity score matching was performed.ResultsBefore propensity score (PS) matching, it was observed that patients in the desmopressin group were significantly older (p<0.001) and had a higher blood pressure (p<0.001), higher serum creatinine (p<0.001), lower hemoglobin levels (p<0.001), and lower platelet counts (p=0.001) than those in the no-desmopressin group. Furthermore, the incidence of renal artery embolization was not significantly different between the two groups (p=0.077); however, blood transfusions occurred significantly more frequently in the desmopressin group (p<0.001). A comparison of the two groups after PS matching did not reveal any differences in the incidence of renal artery embolization (p=0.341), blood transfusion (p=0.579), and total major bleeding events (p=0.442). Furthermore, there was no difference in the incidence of perinephric hematoma on computed tomography or ultrasound (p=0.120).ConclusionsWe do not recommend desmopressin administration before kidney biopsy. (AU)

Antecedentes/objetivos: La complicación más importante de la biopsia renal es la hemorragia y no está claro si la desmopresina es eficaz en su prevención. Por lo tanto, el estudio se realizó para comparar la hemorragia tras una biopsia renal percutánea con o sin prescripción de desmopresina previa a esta.MétodosEn este estudio unicéntrico, retrospectivo y observacional se seleccionaron 3.018 pacientes adultos que se sometieron a una biopsia renal entre el 1 de enero de 2003 y el 31 de marzo de 2019 en nuestro instituto. De ellos, 776 pacientes recibieron desmopresina. Para comparar las diferencias en los acontecimientos de hemorragia mayor entre los pacientes que recibieron desmopresina y los que no, se realizó un emparejamiento por puntuación de propensión.ResultadosAntes del emparejamiento por puntuación de propensión, se observó que los pacientes del grupo con desmopresina tenían una edad significativamente mayor (p<0,001) y presentaban una presión arterial más alta (p<0,001), una creatinina sérica más alta (p<0,001), niveles de hemoglobina más bajos (p<0,001) y recuentos de plaquetas más bajos (p=0,001) que los del grupo sin desmopresina. Además, la incidencia de embolización de la arteria renal no fue significativamente diferente entre los 2 grupos (p=0,077); sin embargo, las transfusiones de sangre se produjeron con una frecuencia significativamente mayor en el grupo con desmopresina (p<0,001). Una comparación de los 2 grupos tras el emparejamiento por puntuación de propensión no reveló diferencias en la incidencia de embolización de la arteria renal (p=0,341), la transfusión de sangre (p=0,579) y los acontecimientos de hemorragia mayor totales (p=0,442). Además, no se observaron diferencias en la incidencia de hematomas perinéfricos en la tomografía computarizada o la ecografía (p=0,120).ConclusionesNo se recomienda la administración de desmopresina antes de una biopsia renal. (AU)

Understanding tubulointerstitial injury and repair mechanisms paves the way for renal outcome improvement in lupus nephritis / Entender la lesión tubulointersticial y los mecanismos de reparación será la vía para mejorar los desenlaces renales en nefritis lúpica

ABSTRACT Despite improvements in patient survival and quality of life, long-term renal survival has not changed significantly in the recent decades and nephritis relapses affect over 50% of patients with lupus nephritis. Renal fibrosis affecting the tubulointerstitial compartment is a central determinant of the prognosis of any kidney disease. Notwithstanding this evidence, the current 2003 ISN/RPS classification still focuses on glomerular pathology and does not include a mandatory score with clear subcategories of the tubulointerstitial injury in the biopsy. The pathogenesis, and the morphological and molecular characteristics of this process in patients with lupus nephritis will be considered, together with a discussion about the concepts the clinician needs to efficiently address in this injury during daily practice and in future clinical trials. Both tubulointerstitial inflammation and fibrosis are strongly correlated with poor renal outcomes in lupus nephritis, regardless of the extent of glomerular damage. Therefore, it is essential to develop reliable and noninvasive approaches to predict which patients are most likely to develop CKD so that appropriate interventions can be adopted before ESRD is established. Currently, no ideal method for monitoring kidney fibrosis exists, since repeated renal biopsies are invasive. Promising methods for assessing and monitoring fibrosis non-invasively include imaging techniques, such as magnetic resonance imaging or ex vivo confocal microscopy, integrated in computational and digital pathology techniques. Finally, beyond specific immunosuppressive treatment in Lupus Nephritis, identifying and treating cardiovascular risk factors should be a cornerstone of treatment in these patients.

RESUMEN A pesar de las mejoras en la sobrevida de los pacientes y su calidad de vida, la sobrevida renal en el largo plazo no ha cambiado significativamente durante las últimas décadas, y las recidivas nefríticas afectan a más del 50% de los pacientes con nefritis lúpica. La fibrosis renal, que afecta el compartimiento tubulointersticial, es un factor determinante central en el pronóstico de todas las patologías renales. A pesar de la evidencia, la actual clasificación ISN/RPS del 2003 todavía se concentra en la patología glomerular y no incluye un score obligatorio con claras subcategorías de la lesión tubulointersticial en la biopsia. Se hablará de la patogenia y las características morfológicas y moleculares de este proceso en pacientes con nefritis lúpica, así como de los conceptos que el clínico necesita para abordar esta lesión de manera eficiente en su práctica cotidiana y en los estudios clínicos a futuro. Tanto la inflamación tubulointersticial como la fibrosis se relacionan fuertemente con desenlaces renales pobres en la nefritis lúpica, con independencia de la extensión del dañío glomerular. Resulta por lo tanto esencial desarrollar sistemas confiables y no invasivos para predecir cuáles pacientes tendrán mayor probabilidad de desarrollar enfermedad renal crónica, a fin de realizar las intervenciones apropiadas antes de que se establezca la enfermedad renal terminal (ERT). En la actualidad, no existe un método ideal para monitorear la fibrosis renal, dado que las biopsias repetidas son procedimientos invasivos. Algunos de los métodos promisorios para evaluar y monitorear la fibrosis de manera no invasiva son las técnicas de imágenes, tales como la resonancia magnética o la microscopía confocal ex vivo, integradas en técnicas de patología computarizadas y digitales. Finalmente, más allá del tratamiento inmunosupresor específico para la nefritis lúpica, identificar y tratar los factores de riesgo cardiovascular deberá ser uno de los pilares de tratamiento en estos pacientes.

[The relevance of electron microscopy in kidney biopsies to 21st century pathology]. / Microscopía electrónica en biopsias renales: una evaluación de su utilidad en el siglo XXI.

INTRODUCTION: Electron microscopy (EM) has been used in the study of renal biopsies for more than 5 decades; however, it is expensive and the possibility of restricting it to selected cases has been considered. This study aims to reevaluate the necessity for EM in the diagnosis of renal biopsies today. MATERIAL AND METHODS: All renal biopsies taken between 2016 and 2019 with adequate light microscopy (LM), immunofluorescence (IF) and EM studies were included. The initial diagnosis (without EM) and the final diagnosis (with EM) was recorded. EM was considered necessary in cases in which the initial and final diagnoses did not concur, when diagnosis could not be made with LM and IF only or if the EM study revealed further clinically relevant findings. RESULTS: A total of 621 biopsies were included, 498 (80.2%) of native kidneys and 123 (19.8%) of transplanted kidneys. In 115 cases (18.5%) EM had been deemed necessary for diagnosis; it was required more frequently in hereditary diseases (96.8%) and isolated hematuria (88.9%) but less often in nephrotic syndrome (6.7%) and renal transplant biopsy (5.7%) (p < 0.001). CONCLUSIONS: EM was required in less than a fifth of renal biopsies, being more necessary in isolated hematuria and hereditary diseases and less so in nephrotic syndrome and in renal graft biopsies. These findings may prove useful as a guide to case selection protocols in which EM could be considered as a non-mandatory technique.

No effect of desmopressin administration before kidney biopsy on the risk of major post-biopsy bleeding.

BACKGROUND/AIMS: The most important complication of kidney biopsy is bleeding, and it is unclear whether desmopressin is effective in preventing it. Thus, the study was conducted to compare post-biopsy bleeding with or without desmopressin prescription prior to percutaneous kidney biopsy. METHODS: In this single-centered, retrospective, and observational study, 3,018 adult patients who underwent kidney biopsy between January 1, 2003 and March 31, 2019 at our institute were recruited. Of these, 776 patients received desmopressin. To compare the differences in major bleeding events between patients administered and not administered with desmopressin, propensity score matching was performed. RESULTS: Before propensity score (PS) matching, it was observed that patients in the desmopressin group were significantly older (p<0.001) and had a higher blood pressure (p<0.001), higher serum creatinine (p<0.001), lower hemoglobin levels (p<0.001), and lower platelet counts (p=0.001) than those in the no-desmopressin group. Furthermore, the incidence of renal artery embolization was not significantly different between the two groups (p=0.077); however, blood transfusions occurred significantly more frequently in the desmopressin group (p<0.001). A comparison of the two groups after PS matching did not reveal any differences in the incidence of renal artery embolization (p=0.341), blood transfusion (p=0.579), and total major bleeding events (p=0.442). Furthermore, there was no difference in the incidence of perinephric hematoma on computed tomography or ultrasound (p=0.120). CONCLUSIONS: We do not recommend desmopressin administration before kidney biopsy.

Consensus document for ultrasound training in the specialty of Nephrology. / Documento de consenso para la formación en ecografía en la especialidad de Nefrología.

Ultrasound is an essential tool in the management of the nephrological patient allowing the diagnosis, monitoring and performance of kidney intervention. However, the usefulness of ultrasound in the hands of the nephrologist is not limited exclusively to the ultrasound study of the kidney. By ultrasound, the nephrologist can also optimize the management of arteriovenous fistula for hemodialysis, measure cardiovascular risk (mean intimate thickness), implant central catheters for ultrasound-guided HD, as well as the patient's volemia using basic cardiac ultrasound, ultrasound of the cava inferior vein and lungs. From the Working Group on Interventional Nephrology (GNDI) of the Spanish Society of Nephrology (SEN) we have prepared this consensus document that summarizes the main applications of ultrasound to Nephrology, including the necessary basic technical requirements, the framework normative and the level of training of nephrologists in this area. The objective of this work is to promote the inclusion of ultrasound, both diagnostic and interventional, in the usual clinical practice of the nephrologist and in the Nephrology Services portfolio with the final objective of offering diligent, efficient and comprehensive management to the nephrological patient.

Utility of transjugular renal biopsy as an alternative to percutaneous biopsy. / Biopsia renal transyugular. La alternativa a la biopsia percutánea en pacientes de alto riesgo.

BACKGROUND AND OBJECTIVES: Transjugular renal biopsies (TRB) are an alternative when percutaneous ultrasound renal biopsy is contraindicated. Few sites are currently carrying out this procedure, with limited literature existing on the indications, complications and diagnostic yield thereof. The aim of the study is to analyse the indications, diagnostic yield, safety and complications of percutaneous transjugular renal biopsies in our site over the last 15 years. MATERIAL AND METHODS: Retrospective descriptive study of all transjugular renal biopsies performed in our site, the Hospital Vall d'Hebron, between 2003 and 2018. For this, an exhaustive review of the clinical records of patients subjected to this procedure during the study period was conducted. RESULTS: 56 TRBs were performed during the study period. Out of the patients, 31 were men (55.4%) and 25 were women (44.6%), with a median age of 62 years (IQ range 25-75 [52.5-69.5]). More than half presented with haematuria at the time of biopsy, with a median creatinine of 2.69 mg/dL (IQ 25-75 [1.7-4.3]) and median proteinuria at 24 hours of 2000 mg (IQ 25-75 [0.41-4.77]).The mean systolic blood pressure (SBP) and diastolic blood pressure (DBP) were 140 +/- 26 mmHg and 75 +/- 15 mmHg, respectively. The biopsy was carried out owing to acute kidney failure in 19 patients, chronic kidney disease in 12 patients and nephrotic syndrome in 10 patients; in 15 patients it was carried out for other reasons. The most frequent TRB indication was technical impossibility in 16 of 56 cases (including infracostal kidneys, obesity and COPD), alterations in haemostasis (n = 6), thrombocytopenia (n = 5) and solitary kidney (n = 7). 12.5% of the biopsies were hepato-renal. Histological diagnoses were obtained in two thirds of the renal biopsies. The average number of cylinders obtained was 2.5 ± 1.3, with the average number of glomeruli being 6.6 ± 6.2. The most frequent histological diagnoses were IgA nephropathy, membranoproliferative glomerulonephritis and thrombotic microangiopathy. Three major complications were observed: fornix rupture and two transfusion requirements due to bleeding and subcapsular hematoma. CONCLUSIONS: In our site, TRB allowed for a histological diagnosis in 2/3 of patients for whom percutaneous ultrasound renal biopsy is contraindicated. This allowed us to diagnose and subsequently treat said patients.

When to perform renal biopsy in patients with type2 diabetes mellitus? Predictive model of non-diabetic renal disease. / ¿Cuándo realizar biopsia renal en pacientes con diabetes mellitus tipo2? Modelo predictivo de enfermedad renal no diabética.

INTRODUCTION: Diabetic nephropathy (DN) is one of the most frequent complications in patients with diabetes mellitus (DM) and its diagnosis is usually established on clinical grounds. However, kidney involvement in some diabetic patients can be due to other causes, and renal biopsy might be needed to exclude them. The aim of our study was to establish the clinical and analytical data that predict DN and no-diabetic renal disease (NDRD), and to develop a predictive model (score) to confirm or dismiss DN. MATERIAL AND METHODS: We conducted a transversal, observational and retrospective study, including renal biopsies performed in type2 DM patients, between 2000 and 2018. RESULTS: Two hundred seven DM patients were included in our study. The mean age was 64.5±10.6 years and 74% were male. DN was found in 126 (61%) of the biopsies and NDRD in 81 (39%). Diabetic retinopathy was presented in 58% of DN patients, but only in 6% of NDRD patients (P<.001). Patients with NDRD were diagnosed of primary glomerulopathies (52%), nephroangiosclerosis (16%), inmunoallergic interstitial nephritis (15%) and vasculitis (8.5%). In the multivariate analysis, retinopathy (OR26.7; 95%CI: 6.8-104.5), chronic ischaemia of lower limbs (OR4,37; 95%CI: 1.33-14.3), insulin therapy (OR3.05; 95%CI: 1.13-8.25), time course of DM ≥10years (OR2.71; 95%CI: 1.1-6.62) and nephrotic range proteinuria (OR2.91; 95%CI: 1.2-7.1) were independent predictors for DN. Microhaematuria defined as ≥10 red blood cells per high-power field (OR0.032; 95%CI: 0.01-0.11) and overweight (OR0.21; 95%CI: 0.08-0.5) were independent predictors of NDRD. According to the predictive model based on the multivariate analysis, all patients with a score >3 had DN and 94% of cases with a score ≤1 had NDRD (score ranked from -6 to 8points). CONCLUSIONS: NDRD is common in DM patients (39%), being primary glomerulonephritis the most frequent ethology. The absence of retinopathy and the presence of microhematuria are highly suggestive of NDRD. The use of our predictive model could facilitate the indication of performing a renal biopsy in DM patients.

Obstructive Acute Kidney Injury with Maintenance of Diuresis: A Case of Ureter Bifidity / Lesión Renal Aguda Obstructiva con Mantenimiento de la Diuresis: Un Caso de BifidezUreteral

Abstract Percutaneous kidney biopsyin transplanted kidneys remains an essential and commonly performed procedure required for diagnostic and prognostic information. Hemorrhage is the main complication of renal graft biopsy. We report a case of a 47-year-old caucasian womanadmitted to perform an ultrasound(US)-guided biopsy of the renal graft. Six hours later, she presented with macroscopic hematuriawhichimproved after urethral catheterization and intravenous hydration. However the hematuria reappeared associated with anemia and worsening of the serum creatinine value. The US study, revealed hydronephrosis with high Doppler derived renal resistive index compatible with clot obstruction.Despite the vesical lavage with drainage of several clots, the patient rapidly progressed to hemorrhagic shock with worsening of renal function. Pelvic computed tomography (CT) revealed calyx and pelvis duplicity and ureter bifidity which merged into a single ureter and inserted into the right anterolateral wall of the bladder. The inferior ureter was enlarged due to an obstructive clot. Most acute obstructive uropathies are associated with significant pain or the abrupt diminution of urine flow. The presence of ureter bifidity in the CT study explained the maintenance of significantdiuresis despite obstruction, located only to the lower ureter but with sufficient functional impact to condition acute kidney injury (AKI).

Resumen La biopsia renal percutánea en riñones trasplantados sigue siendo un procedimiento esencial y común, necesario para obtener información diagnóstica y pronóstica. La hemorragia es la principal complicación de la biopsia de injerto renal. Presentamos un caso de una mujer caucásica de 47 años, quien fue hospitalizada para la realización de una biopsia de injerto renal guiada por ultrasonido (US). Seis horas después, presentó hematuria macroscópica que mejoró después de la cateterización uretral e hidratación intravenosa. Sin embargo, la hematuria reapareció asociada con anemia y empeoramiento del valor sérico de creatinina. El estudio de US reveló, mediante Doppler, una hidronefrosis con alto índice de resistencia renal, compatible con obstrucción por un coágulo. A pesar del lavado vesical con drenaje de varios coágulos, la paciente progresó rápidamente a choque hemorrágico con empeoramiento de la función renal. La tomografía computarizada (TC) pélvica reveló la duplicidad del cáliz y la pelvis y la bifidez ureteral, que se fusionó en un solo uréter y se insertó en la pared anterolateral derecha de la vejiga. El uréter inferior se agrandó debido a un coágulo obstructivo. La mayoría de las uropatías obstructivas agudas están asociadas con dolor significativo o la disminución abrupta del flujo de orina. La presencia de la bifidez del uréter en el estudio de TC explicó el mantenimiento de una diuresis significativa a pesar de la obstrucción, localizada solo en el uréter inferior, pero con suficiente impacto funcional como para provocar insuficiencia renal aguda (IRA).

Rebiopsias en glomerulonefritis asociadas a ANCA: ¿Cuál es su utilidad en la toma de decisiones? / Rebiopsies in ANCA associated glomerulonephritis: What is its use in making decisions?

El objetivo de este estudio fue evaluar la utilidad de la rebiopsia renal en pacientes con glomerulonefritis ANCA en la toma de decisiones. Se incluyeron en forma retrospectiva todos los pacientes con glomerulonefritis ANCA diagnosticados por biopsia renal entre enero de 2002 y mayo de 2017. Se revisó la histología de las rebiopsias y fue correlacionada con los hallazgos clínicos (hematuria, proteinuria y caída del filtrado) y resultados histológicos de la primera y segunda biopsia. Sesenta pacientes (77% mujeres) fueron incluidos. De ellos, 15 (25%) fueron sometidos a una rebiopsia durante el seguimiento. La media de tiempo hasta la rebiopsia fue de 38,4 meses (DS 20,4). En el grupo de rebiopsia, la presencia de hematuria, proteinuria y caída del filtrado glomerular se observó en el 73%, 73% y 60% de pacientes, respectivamente. No encontramos una correlación entre las lesiones activas (semilunas, necrosis) con la presencia de hematuria o caída del filtrado glomerular. En un gran porcentaje, la histología renal mostró progresión en términos de cronicidad y con menor frecuencia lesiones de actividad. A pesar de esto, en el 67% de los pacientes se realizó un cambio de tratamiento, iniciando una nueva terapia de inducción, alcanzando una respuesta renal en el 85% de los casos.

The aim of this study was to evaluate usefulness of renal re-biopsy in patients with ANCA glomerulonephritis in treatment decisions. We included retrospectively all patients with biopsy-proven ANCA glomerulonephritis between January 2002 and May 2017. We analysed patient's baseline characteristics at the time of re-biopsy, presence of microscopic hematuria, proteinuria and/or decline in glomerular filtration rate (GFR) and time to renal relapse/rebiopsy. Data of physicians' decisions after rebiopsy was collected. 60 patients (77% females) were included. Of those, 15 (25%) underwent renal re-biopsy during the follow up based on clinical manifestations. Mean time until re-biopsy was 38.4 months (SD 20.4). In the re-biopsy group, 73% of patients had new onset hematuria, 73% had new onset or worsening proteinuria (40% and 33% respectably), and 60% had decline in the GFR. When analysing histological changes in the repeat biopsy we didn't find a correlation between active lesions (crescents, necrosis etc.) and hematuria. All patients that underwent repeat biopsy were considered to be active but renal histology showed progression in terms of chronicity and rare active histological lesions. Despite this, in 67% of patients, physicians made a treatment change, initiating a new induction therapy regimen and achieving renal response in 85% of patients.

Kidney injury in systemic lupus erythematosus: lack of correlation between clinical and histological data. / Lesiones renales en el lupus eritematoso diseminado: ausencia de relación entre datos clínicos e histológicos.

BACKGROUND: The existence and type of renal involvement influences the prognosis of systemic lupus erythematosus and this information may be critical when it comes to taking appropriate therapeutic decisions. OBJECTIVE: To evaluate statistical correlations between clinical and histological data in patients with biopsied lupus nephropathy. METHODS: Review of clinical information in adult kidney biopsy requests reported between 2002 and 2014 with a definitive clinical and histopathological diagnosis of renal involvement in systemic lupus erythematosus. RESULTS: 134 cases (86% women), aged 15-59 years. Indication for renal biopsy: asymptomatic urinary abnormalities (30%), nephrotic proteinuria without hypoalbuminaemia (9%), nephrotic syndrome (19%), renal failure (40%) and two cases without clinical renal manifestations. The most common lesions were purely proliferative (68%). In patients with asymptomatic urinary abnormalities, 35% were class IV, 30% class III, 23% mixed, 10% class V and 2% class II. In subjects with nephrotic proteinuria, 75% were class IV, 17% mixed and 8% class III. In nephrotic syndrome patients, 46% were class IV, 27% class V, 19% mixed and 8% class III. In renal failure subjects, 67% were class IV, 22% mixed, 7% class III and 4% class V. These proportions were not statistically different. Although class IV showed the worst renal function, almost half (44%) of those without renal failure belonged to this class. CONCLUSION: We could not demonstrate a consistent clinical-pathological relationship that predicts patterns or severity of histological findings based on the clinical profile in patients with systemic lupus erythematosus and renal manifestations. These results highlight the importance of biopsy as a key diagnostic tool in this disease.

Tratamiento endovascular de fístula arterio-calicial en un riñón trasplantado como alternativa frente al tratamiento quirúrgico / Endovascular treatment of an arterio-calicial fistula in a transplanted kidney as an alternative to surgical treatment

Introducción. La biopsia renal es un procedimiento que ha contribuido al conocimiento de las enfermedades renales desde el año 1950. En el caso de los injertos renales es un método diagnóstico para la valuación, tratamiento y seguimiento clínico del trasplante renal. Las complicaciones se han reducido hasta en un 95% con el uso de ultrasonido en tiempo real y agujas de biopsia automáticas. Caso clínico. Presentamos el caso de un paciente joven, de 29 años de edad, que luego de la biopsia desarrolló, como complicación, una fistula arteriovenosa de alto flujo que se resolvió con embolización selectiva. Resultados. La embolización selectiva mejora la función del injerto. Discusión. Las complicaciones más frecuentes son: hematoma perirenal, hematuria macroscópica, fistula arteriovenosa, pseudoaneurisma, obstrucción uretral, hemorragia activa. La fistula arteriovenosa es producida por traumatismo simultáneo sobre la pared de arterias y venas contiguas, dando lugar a una comunicación entre estos vasos. En el Hospital de las Fuerzas Armadas N°1 las indicaciones de biopsia en injertos renales son: biopsias por protocolo, evaluación del estado del injerto, disfunción del injerto en busca de rechazo de tipo humoral, celular y para investigar toxicidad por anticalneurínicos. Conclusiones. La embolización renal selectiva es una técnica poco invasiva y es una alternativa para el tratamiento de la fistula arteriocalicial, evitando de esta manera la nefrectomía del injerto renal.

Introduction. Renal biopsy is a procedure that contributed to the knowledge of kidney disease since 1950. Kidney biopsy is also a diagnostic tool to evaluate renal transplantation and clinical monitoring, as well as, to choose the best treatment. Complications in Renal biopsy were reduced as much as 95% with the use of ultrasound and automatic biopsy needles. Clinical case. We present the case of a young patient, 29 years old, who developed a high flow arteriovenous fistula post renal biopsy, successfully treated by a selective arterial embolization. Discussion. The most frequent complication of kidney biopsies are: perirenal hematoma, macroscopic hematuria, arteriovenous fistula, pseudoaneurysm, urethral obstruction and active hemorr and veins, creating a communication between both vessels. In Hospital de las Fuerzas Armadas N°1, kidney biopsy indications in kidney grafts are: protocol biopsies, kidney grafts evaluation to find graft dysfunction due to humoral or celular rejection and to investigate anticalcineurinic toxicity. Conclusion. Selective renal embolization is a minimally invasive technique and is an alternative for the treatment of the arteriocalicial fistula, thus avoiding nephrectomy of the renal graft.

Correspondencia entre la clínica nefrológica y las lesiones agudas y crónicas halladas en la anatomía patológica de las diferentes clases de Nefritis Lúpica. Hospital Julio C. Perrando, periodo 2000-2018 / Correspondence between the nephrological clinic and the acute and chronic lesions found in the pathological anatomy of the different classes of Lupus Nephritis. Hospital Julio C. Perrando, period 2000-2018

La NL afecta al 70 al 80% de los pacientes con LES. Se estima que cerca de la mitad de los pacientes desarrollará NL en los 10 primeros años de enfermedad, independientemente del sexo o la edad de los mismos, aumentando la mortalidad y la morbilidad y el riesgo de ERC con necesidad de tratamiento sustitutivo en alrededor de un 25% de los pacientes. MÉTODOS Se realizó un estudio descriptivo retrospectivo de corte transversal, de pacientes remitidos al servicio de Nefrología del Hospital Julio C. Perrando con sospecha de NL en el periodo 2000-2018 a los cuales se les realizaron PBR. Se estudiaron variables relacionadas al paciente, edad, sexo, factores de riesgo, presentación clínica, clase de NL, lesiones encontradas en PBR, evolución. Se utilizaron medidas de tendencia central y de dispersión. RESULTADOS Se diagnosticaron 174 pacientes con NL, 87.36% correspondían al sexo femenino y 12.64% al sexo masculino, la edad de diagnóstico de LES fue 68.9 % entre los 14-24 años por igual en ambos sexos, el debut de la NL en 47% fue en el mismo grupo etario. La presentación nefrológica más frecuente fue como Síndrome nefrótico en 26.43%, Síndrome nefrítico 18.39%, Síndrome nefrótico más nefrítico en 24.13%, y 21.83% se presentaban con algún síntoma aislado y/o alteración de la analítica de laboratorios, principalmente la proteinuria. Las lesión aguda que estuvo presente en un 100% de los casos fue la proliferación endocapilar, depósitos subendoteliales en 35.32%, semilunas celulares en 29.94%, exudación leucocitaria 16.76%, infiltrados intersticiales 14.37%, y necrosis fibrinoide en 8.38%. La esclerosis glomerular estuvo presente 32.33%, fibrosis intersticial en 31.13%, atrofia tubular 30.53%, y por último las semilunas fibrosas en 16.76%. La lesión más biopsiada fue la tipo IV en un 62%, la presentación más habitual fue como Síndrome nefrítico y nefrótico de manera conjunta en 32%. De estos pacientes 10 (9.7%) requirieron de TRR. En la IFI se observó un total de 31 biopsias con patrón de "Full House" (18.5%). DISCUSIÓN La NL es una muy importante causa de morbimortalidad en pacientes con LES. Si bien las formas proliferativas y más aún la clase IV son de peor pronóstico y se asocian a síndromes nefrológicos de gran magnitud, un gran porcentaje de estas no tienen manifestación clínica, solo alteración de laboratorio, por lo que es de suma importancia remitir un paciente con LES con alteración de laboratorio al Nefrólogo para poder realizar la correspondiente PBR y guiar el tratamiento

The spectrum of glomerular disease between the years 2003 and 2015 in Columbia: A review of 12,613 cases.

BACKGROUND: The prevalence of glomerular disease (GD) varies according to the different socio-demographic characteristics of each population. For the first time we present the prevalence of the different forms of GD among patients from several different areas of Columbia. METHODS: Data from 12,613 renal biopsies studied at our University Hospital between 2003 and 2015 was reviewed. Pathology results were classified according to a list of renal diseases proposed by various authors. RESULTS: Focal segmental glomerulosclerosis was present in 22%, IgA disease in 21%, Lupus nephritis in 17%, membranous glomerulonephritis in 13% and thin basal membrane disease in 9%. CONCLUSIONS: This study confirms that focal segmental glomerulosclerosis and IgA disease are the most prevalent GDs found in Columbian patients. This is the first study to analyze GDs in a Columbian population and we recommend that a national registry system be created to collect comprehensive information from future research.

Prevalencia del compromiso renal durante el primer año de seguimiento en pacientes con púrpura de Henoch Schönlein en una institución pediátrica de Bogotá, Colombia / Prevalence of kidney involvement during the first year of follow-up in patients with Henoch-Schönlein purpura in a paediatric institution in Bogotá, Colombia

Resumen Introducción: La púrpura de Henoch-Schönlein es la vasculitis más frecuente en la infancia. La afectación renal continúa siendo la causa de morbimortalidad principal en niños. El espectro del compromiso renal va desde manifestaciones leves hasta el desarrollo de síndrome nefrótico o nefrítico, o insuficiencia renal. Objetivo: Determinar las características clínicas al comienzo y el compromiso renal de los pacientes con diagnóstico definitivo de púrpura de Henoch-Schönlein, durante el primer mes, a los 3 meses y al ario de seguimiento. Métodos: Estudio descriptivo, retrospectivo, de pacientes con diagnóstico definitivo de púrpura de Henoch-Schönlein, de la consulta de Reumatología Pediátrica, en una institución de Bogotá, Colombia, en el período comprendido de 2010 a 2016. Resultados: Ochenta y seis pacientes fueron incluidos en el estudio, 42 niñas y 44 niños, edad media de presentación 5,3 años, DE 2,4 años (1a14anos). Se presentó compromiso renal en 39 pacientes (45%). Se evidenció una tendencia mayor a compromiso renal entre los pacientes con artritis (p = 0,053). El hallazgo clínico más frecuente fue proteinuria aislada (49%), seguido de proteinuria/hematuria (28%) y hematuria aislada en el 15%. Había 8/39 pacientes con compromiso renal durante el año de seguimiento que fueron llevados a biopsia, 6 (75%) con compromiso renal al inicio y 25% al mes. El promedio de seguimiento fue de 26,8 meses con una desviación estándar de 17 meses (1 a 72 meses), no hubo disfunción renal a la última valoración en ninguno de los 39 pacientes con compromiso renal. Conclusión: El compromiso renal fue más frecuente en las primeras semanas de la enfermedad, así como en las formas severas.

Abstract Introduction: Henoch-Schönlein Purpura is the most common vasculitis in children, with Henoch-Schönlein Purpura kidney involvement remaining the main cause of morbidity and mortality. The spectrum of Kidney involvement of kidney involvement ranges from mild symptoms to the development of a nephrotic and/or nephritic syndrome or kidney failure. Objective: To determine the clinic features at onset, and kidney involvement of patients with a final diagnosis of Henoch-Schönlein Purpura during the first month, 3 months, and up to the first year of follow-up. Methods: A retrospective study conducted on patients with a final diagnosis of Henoch-Schönlein Purpura in a Paediatric Rheumatology Department in an institution of Bogota, Colombia, during the period between 2010 and 2016. Results: The study included 86 patients, 42 girls and 44 boys. The median age at disease onset was 5.3 years (SD 2.4 years: range1-14years). Kidney involvement was present in 39/86 (45%) patients. A trend to kidney involvement was observed in patients with abdominal symptoms (p=,053). The most frequent clinical finding was isolated proteinuria (49%), followed of proteinuria/haematuria (28%), and isolated hematuria (15%). Renal biopsy was performed on 8/39 patients with Henoch-Schönlein Purpura nephritis. The mean follow-up was 26.8 months (SD 17 months: range 1-72). There was no evidence of kidney damage in the last assessment in any of the 39 patients with kidney involvement. Conclusion: In this group of patients, kidney involvement was more severe and common in the first weeks of the disease onset.

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

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

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

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

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

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