Search

BackgroundImmune checkpoint inhibitor-associated acute kidney injury (ICPi-AKI) has emerged as an important toxicity among patients with cancer.MethodsWe collected data on 429 patients with ICPi-AKI and 429 control patients who received ICPis contemporaneously but who did not develop ICPi-AKI from 30 sites in 10 countries. Multivariable logistic regression was used to identify predictors of ICPi-AKI and its recovery. A multivariable Cox model was used to estimate the effect of ICPi rechallenge versus no rechallenge on survival following ICPi-AKI.ResultsICPi-AKI occurred at a median of 16 weeks (IQR 8–32) following ICPi initiation. Lower baseline estimated glomerular filtration rate, proton pump inhibitor (PPI) use, and extrarenal immune-related adverse events (irAEs) were each associated with a higher risk of ICPi-AKI. Acute tubulointerstitial nephritis was the most common lesion on kidney biopsy (125/151 biopsied patients [82.7%]). Renal recovery occurred in 276 patients (64.3%) at a median of 7 weeks (IQR 3–10) following ICPi-AKI. Treatment with corticosteroids within 14 days following ICPi-AKI diagnosis was associated with higher odds of renal recovery (adjusted OR 2.64; 95% CI 1.58 to 4.41). Among patients treated with corticosteroids, early initiation of corticosteroids (within 3 days of ICPi-AKI) was associated with a higher odds of renal recovery compared with later initiation (more than 3 days following ICPi-AKI) (adjusted OR 2.09; 95% CI 1.16 to 3.79). Of 121 patients rechallenged, 20 (16.5%) developed recurrent ICPi-AKI. There was no difference in survival among patients rechallenged versus those not rechallenged following ICPi-AKI.ConclusionsPatients who developed ICPi-AKI were more likely to have impaired renal function at baseline, use a PPI, and have extrarenal irAEs. Two-thirds of patients had renal recovery following ICPi-AKI. Treatment with corticosteroids was associated with improved renal recovery.

BackgroundDiabetic patients with kidney disease have a high prevalence of non-diabetic renal disease (NDRD). Renal and patient survival regarding the diagnosis of diabetic nephropathy (DN) or NDRD have not been widely studied. The aim of our study is to evaluate the prevalence of NDRD in patients with diabetes and to determine the capacity of clinical and analytical data in the prediction of NDRD. In addition, we will study renal and patient prognosis according to the renal biopsy findings in patients with diabetes.MethodsRetrospective multicentre observational study of renal biopsies performed in patients with diabetes from 2002 to 2014.ResultsIn total, 832 patients were included: 621 men (74.6%), mean age of 61.7 ± 12.8 years, creatinine was 2.8 ± 2.2 mg/dL and proteinuria 2.7 (interquartile range: 1.2–5.4) g/24 h. About 39.5% (n = 329) of patients had DN, 49.6% (n = 413) NDRD and 10.8% (n = 90) mixed forms. The most frequent NDRD was nephroangiosclerosis (NAS) (n = 87, 9.3%). In the multivariate logistic regression analysis, older age [odds ratio (OR) = 1.03, 95% CI: 1.02–1.05, P ConclusionsThe most frequent cause of NDRD is NAS. Elderly patients with microhaematuria and the absence of DR are the ones at risk for NDRD. Patients with DN presented worse renal prognosis and higher mortality than those with NDRD. These results suggest that in some patients with diabetes, kidney biopsy may be useful for an accurate renal diagnosis and subsequently treatment and prognosis.

Background and Aims IgA nephropathy (IgAN) is the most common glomerulonephritis. The presence of ANCAs in this pathology represents a rare coincidence. However, it is not clear if the presence of IgA or IgG ANCAs in these patients could have clinical significance. We aim to describe the presence of IgA and IgG ANCAs in patients diagnosed with IgAN with crescents, and its possible clinical implications. Method Retrospective study from 2013 to 2020, it included all patients diagnosed by kidney biopsy of IgAN with extracapillary proliferation. Outpatient follow-up time was up to 24 months. Demographics and clinicopathologic data, ANCAs subtype, characteristics of the biopsy and treatment at the time of diagnosis/follow up was recollected. Results From 2013 to 2020, 17 adults were diagnosed with IgAN and extracapillary proliferation. 5 patients presented ANCAs, 3 (17%) were IgA ANCAs and 2 (11%) were IgG ANCAs. At diagnosis, the median age was 48 years old (27-75 years, sd. 15), with 9 women (52%). At the time of diagnosis, the most common clinical presentation was hypertension (71%). The laboratory analysis showed that median hemoglobin was 11.7 mg/dl (8.4-14.9 mg/dL, sd. 1.5), median creatinine was 2.2 mg/dL (0.55-5.7 mg/dL, sd. 1.4) and median proteinuria was 3.5 g/mgCr (0.1-12 g/mgCr, sd. 3.5). 7 patients (41%) presented extracapillary proliferation less than 25%, 7 patients presented it between 25% and 50%, and 3 patients (17%) had it in more than 50%. 5 (30%) patients presented fibrinoid necrosis. 1 (6%) patient needed renal replacement therapy upon admission. In terms of treatment, all patients with ANCAs IgAN received endovenous steroids and cyclophosphamide. The mean follow-up time was 6 months. Oral steroids (59%) and mycophenolate (41%) were the most frequent treatments. At six months, the median creatinine was 1.9 mg/dL (0.4-7, sd. 1.78) and the median proteinuria was 1.45 g/gCr (0.12-5.9, sd. 1.84 g/gCr). 3 patients developed end-stage chronic kidney disease and requiring substitute renal therapy; 4 patients died. Statistical analysis did not show differences in clinical characteristics, demographics, kidney function, proteinuria, need for renal therapy replacement or mortality according to the presence or subtype of ANCA. ANCA negative patients presented less than 25% of extracapillary proliferation in renal biopsy (p = 0.04). ANCA positive patients presented more fibrinoid necrosis than ANCA negative patients (p=0.01). Conclusion Given the limited size of our sample, our results do not allow us to be conclusive, showing no significant differences between the ANCA subtypes. However, from the point of renal biopsy, it is observed that patients with negative ANCAs present less extracapillary proliferation; and that patients ANCA positive presented more fibrinoid necrosis.

Background and Aims Kidney biopsy (KB) is the “gold standard” to diagnose nephropathies in our renal patients and it is a procedure with a low rate of complications. Obtaining material for kidney biopsy biobank requires the extraction of one more renal cylinder. The main objective of our study is to analyze the characteristics of a cohort of patients with KB, the safety of the establishment of a renal biopsy biobank with the objective to obtain at least one core of kidney biopsy for research purposes. Method Observational and prospective study of kidney biopsies performed in our center from January 2019 and 2020. We started a collection of kidney biopsy samples to obtain a biobank at January 2019. Therefore, in patients who accepted, instead of two cylinders, three cylinders were obtained during the procedure when possible. Clinical and laboratory data of the patients were reviewed and we looked for risk factors for complications, including the number of cylinders obtained in the procedure. Results We reviewed a cohort of 221 patients in whom we performed a kidney biopsy at our hospital. Eight patients (3.6%) underwent trans-jugular renal biopsy, which we have eliminated from the analysis. Of the remaining 213, 126 (59.2%) were men, the mean age was 56.8 (± 16.9) years, 122 (57.3%) patients had hypertension, 46 (23%) were diabetics, 14 (6.5%) were under anticoagulant treatment and 35 (16.4%) were under antiplatelet treatment. Regarding the analytical values, the mean creatinine was 2.22 (± 1.9) mg / dl, protein / creatinine urine ratio 1119.6 [448.3-2957.9] mg / gr, 44.6% (n = 95) had microhematuria, the median hemoglobin pre-KB was 12.1 (± 2.3) g / dL, 254380 (± 8873) platelets, INR 0.98 (± 0.09), prothrombin time of 11.8 (± 1.16) seconds, systolic blood pressure was 135 (± 24.3) mmHg, diastolic blood pressure was 76 (± 15.5) mmHg. The median kidney size was 11 (± 1.23) cm and cortical size was 1.7 (± 0.65) cm. In 113 (53.1%) patients the right kidney was biopsied. 69.5% (n = 148) of the patients 3 renal sample cylinders were obtained, 27.2% (n = 58) 2 cylinders and in 3.3% (n = 7) one cylinder. We did not found differences regarding of renal and cortical size in the patients according to the number of cylinders obtained. We observed that patients in whom 3 cylinders were had a higher percentage of renal biopsy in the left kidney (p = 0.028). We evidenced minor complications in 13.6% (n = 29) and 3.3% (n = 7) major complications. Patients with complications in KB were older (p = 0.039) and had a higher INR (p = 0.031). Patients with one renal cylinder Jin KB, presented a higher percentage of complications with 57.1% vs 17.2% two cylinders and 14.9% with three cylinder (p =0.014). We did not find differences in terms of complications according to the laterality of kidney biopsy (right vs left). Conclusion Kidney biopsy is a procedure with a low complication rate. Obtaining three renal biopsy cylinders for biobank has not shown an increase in the rate of complications, which remains similar than previously published reports. Our results suggest that the complications are observed mainly in the first and/or second cylinder, and in that case the third core is not performed.

Background COVID-19 infection manifests as pneumonia associated with multiple organ failure, and death. Acute kidney injury is a risk factor for mortality. There is limited scientific literature on COVID-19 infection and allergic tubulointerstitial nephritis, its clinical course and short- and long-term prognosis. Method We performed a retrospective study where medical records of 60 patients with histological diagnosis of allergic tubulointerstitial nephritis from January 2009 to November 2020. In these patients, we studied the incidence of COVID-19 infection, clinical characteristics and prognosis from March to the actual date. Results Of 60 patients with allergic tubulointerstitial nephritis, 6 (10%) patients were diagnosed with COVID-19. The first case, an 85-year-old woman with a history of metastatic melanoma treated with nivolumab and allergic tubulointerstitial nephritis by immunobiological agents in 2018, diagnosed with mild COVID-19 infection in April 2020 without deterioration of renal function in controls at 3 and 6 months of follow-up. The second case, a 51-year-old woman with a history of large B-cell lymphoma with plasmacytic differentiation and progression to multiple myeloma of lambda light chains and allergic tubulointerstitial nephritis due to chemotherapy since 2019, admitted for acute pyelonephritis and PRES syndrome secondary to first dose of bortezomib complicated with COVID-19 nosocomial pneumonia and acute pancreatitis treated with corticosteroids and broad spectrum antibiotic therapy; she died of abdominal refractory septic shock. The third patient, a 64-year-old man without prior renal impairment, was admitted for severe COVID-19 pneumonia and acute kidney injury secondary to acute tubulointerstitial nephritis of uncertain etiology that required orotracheal intubation and continuous veno-venous hemodiafiltration for a week who received methylprednisolone in bolus for 3 days and continued treatment with corticosteroid therapy with complete recovery of renal function and improvement in proteinuria at 3 months of follow-up. The fourth patient, an 82-year-old woman with acute kidney injury AKIN 3 secondary to acute allergic tubulointerstitial nephritis related to ciprofloxacin complicated with severe COVID-19 nosocomial pneumonia, who died despite ventilatory support and high-dose steroids therapy and tocilizumab. The fifth patient, a 75-year-old with a history of metastatic lung adenocarcinoma treated with immunobiological agents and allergic tubulointerstitial nephritis in 2018, admitted in march 2020 for mild COVID-19 pneumonia treated with steroids and hydroxychloroquine without deterioration of respiratory and kidney function. The sixth patient, an 86-years-old man with acute kidney injury AKIN 3 due to acute allergic tubulointerstitial nephritis secondary to proton-binding inhibitors and nosocomial COVID-19 infección with improvement of kidney function with steroids therapy only. Conclusion Our 6 patients with allergic tubulointerstitial nephritis and COVID-19 infection presented different spectrum of the disease. It seems that nosocomial COVID-19 infection in patients admitted with recent diagnosis of acute allergic tubulointerstitial nephritis presented a worse clinical prognosis compared with long-term diagnosed acute tubulointerstitial nephritis. Further studies with a larger sample size are needed.

Background and Aims Angiotensin converting enzyme 2 (ACE2) is one of the components of the renin-angiotensin system (RAS) that mainly degrades angiotensin II to angiotensin-(1-7). ACE2 is predominantly expressed in the kidney and the heart, but it has been evidenced in type 2 alveolar lung cells, where it acts as a receptor for the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In this context, a controversy arose as to whether the use of RAS blockers could increase ACE2 lung expression and the risk infection by COVID-19. This study aimed to investigate the effect of an ACE inhibitor (Ramipril) on ACE2 expression in experimental diabetes. Method 12 weeks old diabetic db/db mice (n=7) were given ramipril (8 mg/Kg/day) during 8 weeks or the respective vehicle. db/m (n=7) vehicle-treated non-diabetic mice were included as controls. ACE2 mRNA expression and enzymatic activity were studied in kidney, heart and lung samples of these animals to identify if the diabetic condition or treatment with ramipril modulated ACE2 expression. Results In vehicle-treated diabetic db/db animals, ACE2 mRNA expression was significantly increased in the kidney (p Conclusion ACE2 is increased in the kidney and the lung, and decreased in the heart of diabetic mice. Ramipril treatment restores ACE2 levels. The results suggest that ACE inhibitors do not increase ACE2 expression and the activity decrease exerted in the lung may be protective against COVID-19 infection.

Malaltia renal crònica; Obesitat; Trasplantament de ronyó Enfermedad renal crónica; Obesidad; Trasplante de riñón Chronic kidney disease; Obesity; Kidney transplantation Obesity is one of the epidemics of our era. Its prevalence is higher than 30% in the U.S. and it is estimated to increase by 50% in 2030. Obesity is associated with a higher risk of all-cause mortality and it is known to be a cause of chronic kidney disease (CKD). Typically, obesity-related glomerulopathy (ORG) is ascribed to renal hemodynamic changes that lead to hyperfiltration, albuminuria and, finally, impairment in glomerular filtration rate due to glomerulosclerosis. Though not only hemodynamics are responsible for ORG: adipokines could cause local effects on mesangial and tubular cells and podocytes promoting maladaptive responses to hyperfiltration. Furthermore, hypertension and type 2 diabetes mellitus, two conditions generally associated with obesity, are both amplifiers of obesity injury in the renal parenchyma, as well as complications of overweight. As in the native kidney, obesity is also related to worse outcomes in kidney transplantation. Despite its impact in CKD and cardiovascular morbility and mortality, therapeutic strategies to fight against obesity-related CKD were limited for decades to renin-angiotensin blockade and bariatric surgery for patients who accomplished very restrictive criteria. Last years, different drugs have been approved or are under study for the treatment of obesity. Glucagon-like peptide-1 receptor agonists are promising in obesity-related CKD since they have shown benefits in terms of losing weight in obese patients, as well as preventing the onset of macroalbuminuria and slowing the decline of eGFR in type 2 diabetes. These new families of glucose-lowering drugs are a new frontier to be crossed by nephrologists to stop obesity-related CKD progression.

Introduction: Kidney donor shortage requires expanding donor selection criteria, as well as use of objective tools to minimize the percentage of discarded organs. Some donor pre-transplant variables such as age, standard/expanded criteria donor (SCD/ECD) definition and calculation of the Kidney Donor Profile Index (KDPI), have demonstrated correlations with patient and graft outcomes. We aimed to establish the accuracy of the three models to determine the prognostic value of kidney transplantation (KT) major outcomes. Material and methods: We performed a retrospective study in deceased donor KTs at our institution. Unadjusted Cox and Kaplan–Meier survival, and multivariate Cox analyses were fitted to analyze the impact of donor age, SCD/ECD and KDPI on outcomes. Results: 389 KTs were included. Mean donor age was 53.6 ± 15.2 years; 163 (41.9%) came from ECD; mean KDPI was 69.4 ± 23.4%. Median follow-up was 51.9 months. The unadjusted Cox and Kaplan–Meier showed that the three prognostic variables of interest were related to increased risk of patient death, graft failure and death-censored graft failure. However, in the multivariate analysis only KDPI was related to a higher risk of graft failure (HR 1.03 [95% CI 1.01–1.05]; p = 0.014). Conclusions: SCD/ECD classification did not provide significant prognostic information about patient and graft outcomes. KDPI was linearly related to a higher risk of graft failure, providing a better assessment. More studies are needed before using KDPI as a tool to discard or accept kidneys for transplantation. Resumen: Introducción: La escasez de donantes de riñón requiere una ampliación de los criterios de selección de donantes, así como el uso de herramientas objetivas para minimizar el porcentaje de órganos descartados. Algunas variables pretrasplante del donante, como la edad, la definición de donante con criterios de selección estándar/ampliados (standard/expanded criteria donor [SCD/ECD]) y el cálculo del índice del perfil de donante renal (Kidney Donor Profile Index [KDPI]) han demostrado correlación con los resultados del paciente y el injerto. Nuestro objetivo fue evaluar la precisión de 3 modelos diferentes para determinar el valor pronostico en los resultados del trasplante renal. Materiales y métodos: Llevamos a cabo un estudio retrospectivo de TR de donantes fallecidos en nuestro centro. Se realizó un analisis de supervivencia mediante curvas de Kaplan-Meir y Cox no ajustado, ai como un analisis multivariante de Cox para analizar el impacto de la edad del donante, la definición SCD/ECD y el índice KDPI sobre los resultados. Resultados: Se incluyeron 389 TR. La media de edad de los donantes era de 53,6 ± 15,2 años; 163 (41,9%) procedían de donantes ECD; el índice KDPI medio era de 69,4 ± 23,4%. La mediana de seguimiento era de 51,9 meses. Los análisis de Kaplan-Meier y de Cox no ajustado mostraron que las 3 variables pronósticas de interés estaban relacionadas con un mayor riesgo de muerte del paciente, fracaso del injerto y fracaso del injerto censurado por la muerte. Sin embargo, en el análisis multivariable solamente el índice KDPI estuvo relacionado con un mayor riesgo de fracaso del injerto (HR: 1,03 [IC 95%: 1,01-1,05]; p = 0,014). Conclusiones: La clasificación SCD/ECD no proporcionó información pronóstica significativa sobre los desenlaces del paciente y el injerto. El índice KDPI estuvo linealmente relacionado con un mayor riesgo de fracaso del injerto, por lo que ofrecía una mejor evaluación. Es necesario realizar más estudios antes de usar el índice KDPI como herramienta para descartar o aceptar riñones para trasplante. Keywords: Donor age, Expanded criteria donor, Kidney Donor Profile Index, Kidney transplant, Palabras clave: Edad del donante, Donante con criterios ampliados, Kidney Donor Profile Index, Trasplante renal

BACKGROUND AND OBJECTIVES: Diabetic kidney disease is the leading cause of end-stage chronic kidney disease. The renin-angiotensin-aldosterone system (RAAS) blockade has been shown to slow the progression of diabetic kidney disease. Our objectives were: to study the percentage of patients with diabetic kidney disease treated with RAAS blockade, to determine its renal function, safety profile and assess whether its administration is associated with increased progression of CKD after 3 years of follow-up. MATERIALS AND METHODS: Retrospective study. 197 diabetic kidney disease patients were included and divided into three groups according to the treatment: patients who had never received RAAS blockade (non-RAAS blockade), patients who at some point had received RAAS blockade (inconstant-RAAS blockade) and patients who received RAAS blockade (constant-RAAS blockade). Clinical characteristics and analytical variables such as renal function, electrolytes, glycosylated haemoglobin and glomerular filtration rate according to chronic kidney disease -EPI and MDRD formulas were assessed. We also studied their clinical course (baseline, 1 and 3 years follow-up) in terms of treatment group, survival, risk factors and renal prognosis. RESULTS: Non-RAAS blockade patients had worse renal function and older age (p

Background/Aims: Recurrent acute kidney injury (AKI) is common among patients after a first hospitalized AKI. However, little is known about the prognosis of recurrent AKI episodes in chronic kidney disease (CKD) development, cardiovascular events and mortality. Methods: A retrospective study included patients admitted to our Hospital from 2000 to 2010. AKI was defined according to the Acute Dialysis Quality Initiative criteria. In the follow-up period after the first AKI episode, clinical, laboratory data and the number of repeated AKI episodes, etiology and severity were recorded. Results: Among the 359 AKI survivor patients included, 250 new AKI episodes were observed in 122 patients (34%). Variables independently associated to new episodes were: type 2 DM [OR 1.2, 95%CI 1.2-3.8, p=0.001], ischemic heart disease [OR 1.9; 95%CI 1.1-3.6, p=0.012], and SCr at the first AKI event>2,6 mg/dl [OR 1.2; 95%CI 1.03-1.42, p=0.02]. Development of CKD during four years follow-up was more frequent in patients with recurrent AKI, HR [2.2 (95% CI: 1.09-4.3, p=0.003)] and 44% of recurrent AKI patients who developed CKD occurred during the first 6 months after the initial event. Cardiovascular events were more frequent among patients with recurrent AKI patients than in those with one AKI episode (47.2% vs 24%, p=0.001). Mortality at 4 years was higher in the patient subgroup with several episodes of AKI as compared with those with a single episode [HR: 4.5 (95% CI 2.7-7.5) pConclusion: Episodes of recurrent AKI have a high potential to be associated with relevant complications such as cardiovascular events, mortality and CKD development.

Severe acute kidney injury (AKI) is associated with chronic kidney disease (CKD), cardiovascular events and increased mortality. However, little is known about the prognosis in hospitalized population suffering from non-severe AKI episodes. The aim of this study is to determine the impact of non-severe AKI episodes in cardiovascular events, mortality and CKD, on short and long term.Retrospective cohort study to 360 patients who met the criteria for diagnosis of AKI according ADQI guidelines with full recovery of renal function after the AKI episode, admitted between January 2000 and December 2010 in our hospital. Follow-up was 4 years after the diagnosis of AKI. Covariates included demographic variables, baseline creatinine and diagnosis of comorbidities.360 AKI survivor patients were included. Twenty five of them (6.7%) had developed CKD after 1-year follow-up. Hypertension (OR 1.62; 95% CI 1.2-2.6, p 0.05) and serum creatinine2.6 mg/dL in AKI (OR 1.7; 95% CI 1.2-3.7, p 0.05) were independent risk factors. After 4-year follow-up, 40 patients (18.3%) had developed CKD; age66 years was an independent risk factor (OR 1.03, 95% CI 1.03-1.06, p 0.05). Mortality rate at 4 years was 25.3% and was significantly higher in CKD patients (OR 4.3, 95% CI 1.13-4.90, p 0.05) and patients66 years (OR 1.12, 95% CI 1.02-1.06, p 0.05). The incidence of cardiovascular events also was higher in CKD patients than in non-CKD patients (62.7 vs. 21.7%, p 0.05).Even after fully recovered non-severe AKI episodes, some patients develop CKD and those have an increase in the incidence of cardiovascular events and long-term mortality.

Malaltia renal crònica; Diabetis mellitus; Malaltia renal diabètica Enfermedad renal crónica; Diabetes mellitus; Enfermedad renal diabética Chronic kidney disease; Diabetes mellitus; Diabetic kidney disease Diabetic kidney disease (DKD) is one of the most relevant complications of type 2 diabetes and dramatically increases the cardiovascular risk in these patients. Currently, DKD is severely infra-diagnosed, or its diagnosis is usually made at advanced stages of the disease. During the last decade, new drugs have demonstrated a beneficial effect in terms of cardiovascular and renal protection in type 2 diabetes, supporting the crucial role of an early DKD diagnosis to permit the use of new available therapeutic strategies. Moreover, cardiovascular and renal outcome trials, developed to study these new drugs, are based on diverse cardiovascular and renal simple and composite endpoints, which makes difficult their interpretation and the comparison between them. In this article, DKD diagnosis is reviewed, focusing on albuminuria and the recommendations for glomerular filtration rate measurement. Furthermore, cardiovascular and renal endpoints used in classical and recent cardiovascular outcome trials are assessed in a pragmatic way. The authors are current recipients of research grants from the Fondo de Investigación Sanitaria-Feder—Instituto de Salud Carlos III (PI17/00257) and REDinREN (RD16/0009/0030).

Diabetes mellitus (DM) is a worldwide health problem due to its high prevalence, incidence and impact on patient morbidity and mortality. Chronic kidney disease (CKD) is one of the most important complications of DM. The indication of renal biopsy in diabetic patients is a widely debated topic and the final decision is usually individualized. The results of renal biopsy in diabetic patients can be classified into three groups: diabetic nephropathy (DN), non-diabetic renal disease (NDRD) or DN plus NDRD (mixed forms). Renal involvement in DN has been widely studied and different pathological classifications have been proposed. Some groups demonstrated a relationship between the pathological classifications in DN and renal prognosis. However, to our knowledge renal biopsy in diabetic patients with DN has not demonstrated an impact on their survival and renal prognosis. Some recent studies suggest that non-proteinuric diabetic patients may be affected of DN. In addition, kidney biopsy in DN under new treatments may have a fundamental role in assessing renal protection or even regression of diabetic histological lesions. On the other hand, the accurate and early diagnosis and subsequent treatment of diabetic patients with NDRD has been shown to benefit both their renal and patient prognosis. Renal involvement in patients with DM is very heterogeneous. Thus, the role of renal biopsy in diabetic patients is becoming increasingly important.

The prevalence of diabetic nephropathy (DN) among diabetic patients seems to be overestimated. Recent studies with renal biopsies show that the incidence of non-diabetic nephropathy (NDN) among diabetic patients is higher than expected. Renal impairment of diabetic patients is frequently attributed to DN without meeting the KDOQI criteria or performing renal biopsy to exclude NDN. In this editorial, we update the spectrum of renal disease in diabetic patients and the impact on diagnosis, prognosis and therapy.

Resumen Antecedentes y objetivos: La afectación renal del diabético solo puede determinarse mediante biopsia renal, que presenta una elevada prevalencia de lesiones no diabéticas. Los objetivos del estudio fueron determinar la predictibilidad de nefropatía no diabética (NND) en diabéticos, estudiar diferencias de supervivencia y pronóstico renal, evaluar las lesiones histológicas en nefropatía diabética (ND) y el efecto de la proteinuria en la supervivencia y pronóstico renal en esta población. Material y métodos: Estudio descriptivo y retrospectivo de las biopsias renales de diabéticos entre 1990 y 2013 en nuestro centro. Resultados: Incluimos a 110 pacientes: 87 hombres (79%), con una edad media de 62 años (50-74), creatinina sérica media de 2,6 mg/dl (0,9-4,3) y proteinuria de 3,5 g/24 h (0,5-6,5). El 34,5% presentaban ND, el 61,8% NND y el 3,6% ND + NND. La NND más frecuente fue nefropatía IgA (13,2%). En el análisis multivariado, se asociaron de forma independiente a NND: edad (OR 1,068; IC 95%: 1,010-1,129; p = 0,022), años de diabetes (OR: 0,992; 0,987-0,998; p = 0,004), creatinina (OR: 1,48; 1,011-2,172; p = 0,044), proteinuria de 24 h (OR: 0.813; 0,679-0,974; p = 0,025) y retinopatía diabética (OR: 0,23; 0,066-0,808; p = 0,022). No hallamos diferencias de supervivencia ni de pronóstico renal. Entre los pacientes con ND, presentaban mayor expansión nodular mesangial los que tenían proteinuria nefrótica (p = 0,02), así como peor pronóstico renal (p = 0,004) comparado con proteinuria no nefrótica. No evidenciamos diferencias en la supervivencia del paciente. Conclusiones: La causa más frecuente de NND fue nefropatía IgA. Los pacientes con mayor edad, creatinina, menor duración de diabetes, ausencia de retinopatía diabética y menor proteinuria presentan mayor riesgo de NND. Los pacientes con ND y proteinuria en rango nefrótico tuvieron peor pronóstico renal. Abstract Background and objectives: Diabetic renal lesions can only be diagnosed by kidney biopsy. These biopsies have a high prevalence of non-diabetic lesions. The aims of the study were to determine the predictability of non-diabetic nephropathy (NDN) in diabetics and study differences in survival and renal prognosis. In addition, we evaluated histological lesions and the effect of proteinuria on survival and renal prognosis in patients with diabetic nephropathy (DN). Material and methods: A descriptive, retrospective study of kidney biopsies of diabetics between 1990 and 2013 in our centre. Results: 110 patients were included in the study: 87 men (79%), mean age 62 years (50-74), mean serum creatinine 2.6 mg/dl (0.9-4.3) and proteinuria 3.5 g/24 hours (0.5-6.5). 61.8% showed NDN, 34.5% showed DN and 3,6% showed DN+NDN. The most common NDN was IgA nephropathy (13,2%). In the multivariate analysis, creatinine (OR: 1.48, 1.011-2.172, p = 0.044), proteinuria/24 hours (OR: 0.813, 0.679-0.974, p = 0.025), duration of diabetes (OR: 0.992, 0.987-0.998, p = 0.004), age (OR: 1.068, 95% CI: 1.010-1.129, p = 0.022), and diabetic retinopathy (OR: 0.23, 0.066-0.808, p = 0.022) were independently associated with NDN. We did not find any differences in survival or renal prognosis. Concerning patients with DN, increased nodular mesangial expansion (p = 0.02) and worse renal prognosis (p = 0.004) were observed in nephrotic proteinuria as compared to non-nephrotic proteinuria. We did not find differences in patient survival. Conclusions: The most common cause of NDN was IgA nephropathy. Higher creatinine levels, shorter duration of diabetes, absence of diabetic retinopathy, lower proteinuria, and older age were risk factors for NDN. Patients with DN and nephrotic-range proteinuria had worse renal prognosis.