Use Of Renal Biopsy Research Articles

Anatomo-clinical and Etiological Profile of Nephropathies Biopsied in the Nephrology Department of the Thies Regional Hospital (Senegal)

Introduction: In many developing countries, particularly in Africa, the use of renal biopsy (RB) in clinical nephrology is severely lacking. The objectives were to describe the anatomoclinical and etiological profile of these biopsied nephropathies, as well as the factors associated with the etiology of the nephropathies. Patients and method: This was a retrospective descriptive and analytical study from 1 April 2020 to 30 October 2022. The patients were selected from the renal biopsy register of the nephrology department of the Thiès Regional Hospital. Sociodemographic, clinical, biological, and histological parameters were studied. Results: 75 renal biopsies were included. The mean age was 33.3 ± 14.8 years, with a male predominance (65.3%). The main indications were nephrotic syndrome in 50.67% of cases. RB was adequate in 82.7%, inadequate in 13.3%, and borderline in 4%. Glomerular nephropathies predominated, with focal segmental glomerulosclerosis (FSGS) in 34.7%, membranous nephropathy (MN) in 17.3%, minimal change disease (MCD) in 10.67%, extracapillary glomerulonephritis (ECGN) in 5.3% and lupus nephritis (LN) in 3.9%. Thrombotic microangiopathy (TMA) was found in 9.3%. Chronic tubulointerstitial nephropathy (CTIN) accounted for 5.3% of all RB and acute tubular necrosis (ATN) for 4%. The etiologies were primary in 48%, secondary in 28%, and undetermined in 24%. In the bivariate analysis, the etiology was correlated with the mean SBP (p = 0.023), the mean level of hemoglobin (p = 0.028), the levels of GFR (p = 0.017), and the type of kidney disease (p = 0.000). Conclusion: Glomerular nephropathy was more frequent and FSGS was the most common histological lesion found. Primary causes predominated. Associated factors were identified to improve patient management.

Renal Biopsy: History and Perspectives

Renal biopsy (RB) is a valuable diagnostic tool. This review discusses RB used in Russia in research and practice since the 1980s. Among others the role of RB in the following conditions is analyzed: glomerulo- and pyelonephritis, arterial hypertension, alcoholism, diabetes mellitus and urinary tract malformations in children. The material used in certain studies was unique: wedge or core biopsies in hydronephrosis, acute and chronic pyelonephritis. The collection of RBs was associated with risk, in particular, intra-operative biopsies in acute pyelonephritis and hydronephrosis. Morphological overdiagnosis of mesangioproliferative glomerulonephritis resulted in the overtreatment with steroids and cytostatica in some cases. The main conclusion is that, considering possible adverse effects, RB for research should not exist as such; it must always be performed according to clinical indications. If a patient gives informed consent to research on renal tissue obtained for diagnostic purposes, it can be done, provided that enough tissue remains for the diagnostics. High level of integrity, quality of specimens and of their examination must be a precondition for the use of RB in research and practice.

#2944 BIOPSY-PROVEN ACUTE TUBULOINTERSTITIAL NEPHRITIS IN PATIENTS ON IMMUNE CHECKPOINT INHIBITORS: A POOLED ANALYSIS OF CASE REPORTS

Abstract Background and Aims Acute kidney injury (AKI) is a major complication in cancer patients receiving immune checkpoint inhibitors (ICIs). Previous studies have not accurately distinguished the various potential underlying causes of AKI due to the limited use of renal biopsy. Here, we reviewed cases of biopsy-proven acute tubulointerstitial nephritis (ATIN) in patients treated with ICIs to describe the clinical and laboratory characteristics and outcomes of this condition. Method We conducted a pooled analysis of clinical cases published up to 1 May 2022. The search terms on PubMed were [(Pembrolizumab OR Nivolumab OR Ipilimumab OR Atezolizumab OR Avelumab OR Durvalumab) AND (Nephritis)]. Only cases with biopsy-proven ATIN were included. Among a total of 111 patients identified, 83 were eligible for this analysis. We added two patients from our Institution. We collected data on clinical characteristics, renal biopsy findings, and laboratory examinations. AKI was graded according to the KDIGO criteria. As outcomes, we considered: complete renal recovery if serum creatinine returned to baseline +0.3 mg/dL, no recovery if patients needed dialysis and partial recovery in other cases. Results Overall, 85 patients (56 male) with an age of 61.4±19 years were evaluated. 43 patients (51%) had melanoma, 25 (30%) non-small cell lung cancer, 8 renal carcinoma, and 9 other cancers. ICI treatment consisted of PD-1, PDL-1 (nivolumab, pembrolizumab, atezolizumab) and CTLA4 inhibitors (i) (ipilimumab) or combination PD-1i-CTLA4i (Table 1). Renal toxicity developed after a median of four cycles of therapy, but in most cases (n = 59) after at least three treatment cycles. Eleven patients (14%) presented with AKI stage 1, 16 patients (20.5%) with stage 2, and 51 patients (65.5%) with AKI stage 3, including five patients requiring dialysis. Among AKI3 patients there was a significantly higher prevalence of patients at the first therapy line (p = 0.04), while all the 19 patients treated with the dual ICI blockade developed AKI3, compared with 29 patients out of the 52 taking a single agent (Figure 1A). Seventy-seven patients received steroids, while 7 patients did not receive any therapy. ICI treatment was withdrawn in 65 out of 69 patients with available data. Following AKI resolution, in 15 patients ICI was restarted, but in six (40%) AKI recurred. Overall, 32 patients (40%) presented a complete renal recovery, 45 patients (56.2%) had a partial recovery, and 3 patients (3.8%) did not recover. Among patients who did not fully recover, there was a higher prevalence of those treated with dual ICI blockade and presenting with AKI stage 3 (Figure 1B). At logistic regression, complete renal recovery was inversely associated with dual ICI blockade (OR 0.1, 95CI 0.02-0.5, p = 0.006) and AKI 3 (OR 0.31, 95CI 0.1-0.9, p = 0.04), but only the association with dual ICI therapy remained significant at multivariate analysis. Conclusion ICI-related ATIN may develop late after the initiation of therapy. It may present as a severe form of AKI, particularly in patients with dual ICI blockade. Although this complication may be partially reversible, concerns remain about the renal function sequelae and the possibility of restarting treatment after AKI resolution due to the risk of recurrence.

The use of renal biopsy in the kidney tumor management: A retrospective analysis of consecutive cases in a referral center

Ultrasound-guided renal masses biopsy (RMB) is a useful and underestimated tool to evaluate suspected renal tumors. This study aimed to assess the safety and feasibility of this technique. Data of 80 patients with suspected primary or secondary kidney tumors who underwent RMB between January 2012 and December 2020 were included in this retrospective study. Twelve patients were excluded due to incomplete data. Biopsy outcomes were collected through our electronic medical records system and then compared with definitive pathology. RMB was performed in 68 cases. Pathological examination reported 43 (63%) malignant cases, while RMB was negative in 15 (22%) samples. On the other hand, a benign lesion was present in 8 (12%) cases, and 2 (3%) biopsies were non diagnostic. One major and one minor post-procedure complication were reported among the patients. A total of 31 patients underwent renal surgery including 19 partial and 12 radical nephrectomies. Out of them, 4 patients had a negative biopsy, but radiological imaging strongly suggested malignancy. The concordance between biopsy and definitive pathology occurred in 22 out of 31 (71%) cases, with a higher rate among the masses greater than 4 cm, 9/11 (82%) compared to smaller ones 13/20 (65%). Pathologic examination of the 4 cases with negative biopsy showed 3 renal cell and a translocation renal cell carcinoma. Ultrasound-guided biopsy for renal masses is a safe and effective procedure. Its ability to identify malignancy is evident, especially for primary renal tumors. However, low concordance between biopsy and definitive pathology in cases with negative biopsies, especially for tumors < 4 cm, does not reliably guarantee the absence of tumor and, therefore, strict follow-up or repeat biopsy may be indicated.

Utility of renal biopsy in differentiating idiopathic multicentric Castleman disease from IgG4-related disease.

Idiopathic multicentric Castleman disease (iMCD) is a subtype of human herpesvirus type 8 (HHV-8)-related Castleman disease that causes multi-organ damage, including kidney damage due to polyclonal lymphoproliferation and interleukin (IL)-6-induced cytokine storm. However, its renal pathological findings are unclear. We report the case of a woman in her 80s who was diagnosed with iMCD based on renal pathological findings. Five years ago, hypergammaglobulinemia was detected, and her renal function declined. Renal biopsy revealed plasma cells infiltrating the stroma. Immunostaining revealed numerous IgG4-positive plasma cells. The serum IgG4 level was high, and she was initially diagnosed with IgG4-related disease (IgG4-RD) and treated with steroids. However, the therapeutic effect was poor. On re-examination, computed tomography revealed lymphadenopathy around the aorta and spleen. Renal histopathology showed numerous IL-6-positive plasma cells. Anemia and C-reactive protein (CRP) positivity persisted despite steroid administration. HHV-8 was negative, and polyneuropathy, organomegaly, endocrinopathy, M-protein, and skin changes syndrome was not suspected. Thus, iMCD was diagnosed. Based on previous reports, there is no significant difference in IgG4 levels between iMCD and IgG4-RD, and IgG4-positive plasma cell infiltrates were observed in iMCD-affected organs. Therefore, it may be difficult to distinguish iMCD from IgG4-RD. In this case, high-serum IL-6 and CRP were observed, which are usually not seen in IgG4-RD but are common findings in iMCD, leading to the diagnosis. Patients with deep lymphadenopathy may be diagnosed with iMCD based on renal pathological findings. Renal biopsy is recommended for patients with suspected iMCD and decreased renal function.

Patterns of biopsy-proven renal disease in people living with HIV: 10\xa0years experience in Sydney, Australia

BackgroundAcute and chronic kidney diseases are important comorbidities in People Living With HIV (PLWH). Biopsy is often pursued in this cohort with ongoing renal impairment without a clear aetiology, in order to establish the diagnosis and to guide management. Despite the importance of renal disease in PLWH, there is a paucity of biopsy data—especially in the Australian setting. Consequently, who and when to biopsy is mainly based on clinical experience. The aims of this study were to describe biopsy-proven renal disease in PLWH at our institution and to assess for correlation between any demographic or laboratory characteristics with histological diagnosis.MethodsA retrospective review of all PLWH who underwent renal biopsy between January 2010 and December 2020 at Royal Prince Alfred Hospital, Sydney, Australia was performed. All PLWH over 18 years, who were not transplant recipients were included. Demographic, laboratory and biopsy data was extracted from the electronic medical records. Basic descriptive statistics were performed, and correlation was assessed using chi square and Kendall’s coefficient of rank test.Results19 renal biopsies were included in the study. The majority of PLWH were Australian born (53%), male (84%) and had a mean age of 48 years (SD 13). Comorbid hypertension and diabetes were present in 74% and 21% of people respectively. The mean serum creatinine was 132 µmol/L (SD 55) and the mean estimated glomerular filtration rate (eGFR) was 61 ml/min/1.73m2 (SD 24). The most common histological diagnosis was tubulointerstial nephritis in 5 people (24%). Hypertensive glomerulosclerosis and IgA nephropathy were present in 4 (19%) and 3 (14%) people respectively. There were no cases of HIV-associated nephropathy. There was no significant correlation between any cohort characteristics and diagnoses.ConclusionsThis study represents the first description of biopsy-proven kidney disease in the HIV-infected population of Australia. Our results support the use of renal biopsy in PLWH with ongoing renal impairment for accurate diagnosis and to guide further management. Although a small sample size, our study is larger than other published international biopsy studies.

47-Year-Old Woman With Bilateral Flank Pain

47-Year-Old Woman With Bilateral Flank Pain

Learning curve for the laparoscopy-guided kidney biopsy procedure in small corpses of dogs and pigs.

The use of renal biopsy through laparoscopy is increasingly present both in human and veterinary medicine. However, both techniques require skill and training to make the operator capable to do it. The learning curve allows the quantitative and qualitative assessment of the number of attempts and minimum time for the surgical procedure. The objective included establish the learning curve for laparoscopy-guided kidney biopsy procedures in dog and pig corpses. Six dogs and six pigs corpses weighing less than 10 kg were used for this study. All corpses underwent kidney biopsy performed through laparoscopy. Twenty-four operators, two per animal, performed 20 renal biopsies each (10 for each kidney), with 480 collection-procedures in total. Duration and difficulty of the procedure and the biopsy sample quality were evaluated and statistical analysis was performed using a mixed regression model with a random effect of individuals and multivariate analysis of data. There were 91.5% of the samples that were adequate for evaluation. There was no significant difference in the number of glomeruli or cortex percentage considering the attempts in either species, demonstrating the operator’s ability since first collection. Swine samples showed higher amounts of renal cortex than canine samples. The procedure duration was shorter as more attempts were performed in dogs and pigs. From the fourth repetition, the professional reached a plateau for the variable related to ‘collection’, and from the second, the professional presented uniform duration for ‘sample storage’. Operators of the swine model acquired more agility than the dog ones. The variable ‘difficulty’ decreased as more repetitions were performed, reaching a plateau in the sixth attempt. Seven renal biopsies laparoscopy-guided are required for an operator to be considered ‘capable’ to perform the procedure in the referred species included. The learning curve for image-guided kidney biopsy procedures improves the implementation of this technique and benefits patients that undergo this procedure.

Overall Survival of Biopsy-confirmed T1B and T2A Kidney Cancers Managed With Observation: Prognostic Value of Tumor Histology.

The natural history of T1b (4-7 cm) or T2a (> 7-10 cm) kidney cancers managed with observation is not well-understood. The aim of our study was to determine if the addition of histologic subtype to a predictive model of overall survival (OS) that includes covariates for competing risks in observed, biopsy-proven, T1b and T2a renal cell carcinomas (RCCs) improves the model's performance. We queried the National Cancer Database for patients with biopsy-proven stage T1b or T2a RCC and managed nonoperatively between 2004 and 2015. OS was estimated by Kaplan-Meier curves based on histologic subtype. The concordance index (c-index) from a Cox proportional hazards model was used to estimate the extent to which histologic subtypes predict survival for each stage when included in a model along with competing risks of age, gender, race/ethnicity, insurance status, area-level socioeconomic indicators, Charlson-Deyo index, and tumor grade. A total of 937 patients (754 with T1b and 185 with T2a) with biopsy-proven RCC were identified. Kaplan-Meier analysis suggested differences in OS by histologic subtype where sarcomatoid, followed by clear cell, papillary, and chromophobe, had the highest mortality risk at 1, 3, and 5 years. However, there was marginal improvement in the multivariable model of OS using competing risks and histology (c-index, 0.64 and 0.697) compared with competing risks alone (c-index, 0.631 and 0.671) for T1b and T2a RCCs, respectively. In patients with T1b or T2a RCC managed with observation, incorporation of histologic subtype into a risk-stratification model to determine prognostic OS did not improve modeling of OS compared with variables representing competing risks. Histologic subtype of observed T1b and T2a RCC appears to have prognostic OS value when not considering competing risks. These findings may impact the usefulness of renal biopsy to inform decision-making when managing patients with T1b and T2a renal tumors with observation.

NOVEL HUMAN KIDNEY CELL SUBSETS IDENTIFIED BY MUX-SEQ

Abstract Background The kidney is a highly complex organ that performs multiple functions necessary to maintain systemic homeostasis, with complex interplay from different kidney sub-structures and the coordinated response of diverse cell types, few known and likely many others, as yet undiscovered. Traditional global sequencing techniques are limited in their ability to identify unique and functionally diverse cell types in complex tissues. Methods Herein we characterize over 45,000 cells from 10 normal human kidneys using unbiased single-cell RNA sequencing. We also apply, for the first time, an approach of multiplexing kidney samples (Mux-Seq), pooled from different individuals, to save input sample amount and cost. We applied the computational tool Demuxlet to assess differential expression across multiple individuals by pooling human kidney cells for scRNA sequencing, utilizing individual genetic variability to determine the identity of each cell. Results Multiplexed droplet single-cell RNA sequencing results were highly correlated with the singleplexed sample run data. One hundred distinct cell cluster populations in total were identified across the major cell types of the kidney, with varied functional states. Proximal tubular and collecting duct cells were the most heterogeneous, displaying multiple clusters with unique ontologies. Novel proximal tubular cell subsets were identified with regenerative potential. Trajectory analysis demonstrated evolution of cell states between intercalated and principal cells in the collecting duct. Conclusions Healthy kidney tissue has been successfully analyzed to detect all known renal cell types, inclusive of resident and infiltrating immune cells in the kidney. Mux-Seq is a unique method that allows for rapid and cost-effective single cell, in depth, transcriptional analysis of human kidney tissue. Significance Statement Use of renal biopsies for single cell transcriptomics is limited by small tissue availability and batch effects. In this study, we have successfully employed the use of Mux-Seq for the first time in kidney. Mux-Seq allows the use of single cell technology at a much more cost-effective manner by pooling samples from multiple individuals for a single sequencing run. This is even more relevant in the case of patient biopsies where the input of tissue is significantly limited. We show that the data from overlapping tissue samples are highly correlated between Mux-Seq and traditional Singleplexed RNA seq. Furthermore, the results from Mux-Seq of 4 pooled samples are highly correlated with singleplexed data from 10 singleplex samples despite the inherent variability among individuals.

P0474UTILITY OF NATIVE KIDNEY BIOPSY IN OLDER ADULTS: SAFETY AND DIAGNOSES

Abstract Background and Aims Population aging is an increasing phenomenon worldwide and consequently more are developing kidney diseases which may necessitate diagnostic kidney biopsy. However, older patients may be at increased risk for complications such as bleeding. We aimed to examine the utility and safety of native kidney biopsies among our older adults. Method This was a single-centre retrospective study of older adults (≥60 years) who had native kidney biopsies at the Singapore General Hospital between June 2011 and March 2015. Demographic data, co-morbid illnesses, clinical presentation at kidney biopsy, as well as laboratory results before and after kidney biopsy, were retrieved from electronic medical records. Patient outcomes were recorded until their last visit or death before 30th March 2017. End stage renal disease (ESRD) was defined as estimated glomerular filtration rate (eGFR) &amp;lt;15 ml/min/1.73 m2 or need for renal replacement therapy persisting &amp;gt;3 months. All post biopsy bleeding events were documented, with major bleeding defined as the need for transfusion and/or intervention; or if bleeding was either a direct or contributory cause of death. Results Older adults accounted for 153 of 545 (28.1%) native renal biopsies performed. The indications for biopsy in older adults included microscopic hematuria with proteinuria (51.0%), nephrotic syndrome (32.0%) and isolated proteinuria (17.0%). One hundred and ten patients (71.9%) had eGFR &amp;lt;60ml/min/1.72m2 at biopsy and a significantly higher proportion of older patients (85.5% vs 62.4%, p&amp;lt;0.001) had eGFR &amp;lt;30ml/min/1.72m2. Compared to the younger individuals &amp;lt;60 years old, older patients were more likely to be hypertensive (86.3% vs 58.4%, p&amp;lt;0.001) and diabetic (49.0% vs 28.1%, p&amp;lt;0.001). Post biopsy, major bleeding was more frequent among older adults compared with younger adults (13.3% vs 5.7% respectively; p=0.04), although overall bleeding episodes between older and younger adults were not significantly different (15.9% vs 22.9% respectively; p=0.18). Among older adults, minimal change disease (MCD) or focal segmental glomerulosclerosis (FSGS) was the most frequent diagnosis (23.5%), followed by membranous nephropathy (20.9%) and IgA nephropathy (9.8%), whereas MCD/FSGS (26.5%), lupus nephritis (24.5%) and IgA nephropathy (19.6%) were the top three diagnoses amongst younger adults. Co-existing glomerulonephritis (GN) with diabetic nephropathy and isolated diabetic nephropathy were seen in 12 (7.8%) and 20 (13.1%) elderly patients respectively. The majority (124 patients, 81.0%) of biopsies in older adults had histological diagnoses of glomerulonephritis that were potentially amendable to treatment although only 90 (58.8%) patients subsequently received immunosuppressants. Among older adults with biopsy-proven glomerulonephritis, median follow up was similar between those treated and not treated with immunosuppressants (30.4 [27.3, 53.7] months versus 38.8 [30.7, 51.9] months, p=0.12). Among older adults with GN, ESRD was less frequent among those treated with immunosuppressants, compared to those who did not receive immunosuppressants, although the difference did not reach statistical significance (10.3% versus 18.9%, p=0.24). However, the combined endpoint of ESRD or mortality were similar (24.1% vs 21.6%, p=0.76). Conclusion Our findings support the utility of renal biopsy for diagnosis and to guide clinical care. Older adults undergoing kidney biopsy should be counselled and monitored for bleeding complications.

SUN-414 Renal biopsy in the elderly: indications, outcomes and prognostic factors A retrospective study about 70 patients

Advances in health have led to longer life expectancy in all countries and as life expectancy increases, the number of elderly patients with kidney disease increases. The complexity of kidney damage in the elderly obscures the clinical picture. Without a renal biopsy, establishing a good diagnosis may be impossible, or at least prolonged. In this context fits our study that aims to clarify the main indications of renal biopsy and histological diagnostics in the elderly while specifying the risk factors for end-stage renal disease (ESRD). A retrospective observational study was conducted in elderly patients (≥65 years) who had received renal biopsies over 14 years (between January 2003 and December 2016). Demographic, clinical and pathological data at the time of the biopsy were collected from the medical records. Follow-up records and prognostic factors were studied. Outcomes of the renal biopsy were compared to a control group of patients aged between 40 and 64 years. The elderly accounted for 7.25% of native renal biopsies that were performed for 14 years. We included 70 patients in the study, 48 males (68.6%) and 22 females (31.4%). The most common indications for biopsy were an acute renal failure (72,8%) and nephrotic syndrome (24,3%). Common diagnosis included crescentic glomerulonephritis (27%), diabetic nephropathy (12,9%) and postinfectious acute glomerulonephritis (10%). In at least 48.5% of cases, renal biopsy showed histological lesions that can benefit from a therapeutic intervention. In the multivariate analyses, serum creatinine on admission was the only independent factor of poor renal outcome. Comparing histological outcomes with the control group, we found that crescentic glomerulonephritis was more common in the elderly with a significant difference and membranous nephropathy was more common in adults aged 40 to 64 years without significant difference with the elderly. The results of our study confirm the usefulness of renal biopsy in the elderly. Even in patients whose renal biopsy does not show lesions that can modify the therapeutic attitude, it can inform on the prognosis and /or avoid the prescription of the heavy treatments.

Predictive Significance of Renal Histopathology as Correlated with Renal Function in Patients of Nephrotic Syndrome

Background: The advent of renal biopsy in early 1950’s has greatly enhanced the understanding of renal disease including nephrotic syndrome in all areas of clinical nephrology, pathology and investigations. The biopsy data, complemented by appropriate clinical, laboratory information and basic studies has contributed significantly to the body of knowledge of renal disease. Material and methods: This study was undertaken to analyze the usefulness of renal biopsy in patients of nephrotic syndrome. The present study was conducted on 52 patients of nephrotic syndrome, with detailed clinical examinations, relevant biochemical investigations and these patients were subjected to renal biopsy for detailed histopathological examination. Results: Of the 52 cases, 34 (65.4%) were male and 18 (34.6%) were females with male to female ratio of 1.9:1 and mean age being 29.5+ 12.5 years. Pre-biopsy clinical assessment revealed the major cause of nephrotic syndrome as primary glomerular disease in 42 (80.8%). Secondary cause of nephrotic syndrome was suspected in the remaining 10 (19.2%) of patients. After pathological evaluation, the major cause of nephrotic syndrome observed in the present study was primary glomerular diseases which accounted for 40 (76.9 %) patients. Secondary glomerular diseases were observed in the remaining 12 (23.1%) patients. Post biopsy histopathological diagnosis lead to change in therapy in 67.4% of the patients and the alteration of therapy post biopsy most commonly revolved around the use of corticosteroid. In 8 patients therapy with cytotoxic drugs was started. Conclusion: The estimate of prognosis was in agreement (pre-biopsy and post-biopsy) in 61.5 % of cases whereas in 20 (38.5%) patients it was different. In 12 (23.1%) cases a better prognosis was estimated and in 8 (15.4%) cases it was worse than estimated previously.

Predicting long-term renal and patient survival by clinicopathological features in elderly patients undergoing a renal biopsy in a UK cohort.

BackgroundSeveral publications have demonstrated the use of renal biopsy in elderly patients in establishing a diagnosis and enabling directed therapy. However, evidence on the long-term outcomes following biopsies is lacking. The aim of this study is to describe the renal and patient outcomes in elderly patients according to indication for biopsy, clinical parameters and the histological diagnosis.MethodsWe performed a retrospective cohort study of 463 patients >70 years old who underwent a renal biopsy at our centre between 2006 and 2015.ResultsThe median age of the patients was 74.8 (range 70.0–89.6) years. The most frequent primary diagnoses were pauci-immune crescentic glomerulonephritis (GN; 12%), acute interstitial nephritis (10.8%) and membranous GN (7.1%). Death-censored renal survival at 1 and 5 years following the index biopsy was 85.2 and 75.9%, respectively, and patient survival at 1 and 5 years was 92.2 and 71.6%, respectively. Patients who progressed to end-stage renal disease (ESRD) were at higher risk of dying compared with patients who did not require dialysis [hazard ratio 2.41 (95% confidence interval 1.58–3.68; P < 0.001]. On multivariate analysis, factors associated with the risk of progression to ESRD were creatinine (P < 0.001), heavy proteinuria (P = 0.002) and a non-chronic kidney disease (CKD) biopsy indication (P = 0.006). A histological diagnosis of primary GN (P = 0.001) or tubulointerstitial nephritis (P = 0.008) was associated with a favourable renal outcome, while patients with vasculitis and paraprotein-related renal disease (PPRD) had the highest risk of requiring dialysis (P = 0.0002 and P = 0.003, respectively). PPRD was also an independent risk factor for death.ConclusionsThis study demonstrates that renal biopsies in the elderly not only enable directed therapy, but also provide prognostic information on renal and patient survival.

Non-Diabetic Nephropathies among Diabetic Patients of the Nephrology Department of Dakar

Introduction: Diabetic nephropathy is the most common cause of kidney disease in diabetics. However, in some cases the clinical symptoms is not typical and nephropathy may be different from diabetic and require the use of renal biopsy (RB) which is not usually indicated unless non-diabetic nephropathy (NND) is suspected. The objective of this study was to evaluate the prevalence of non-diabetic nephropathy (NDN) among the diabetic patients and to analyse the different predictive factors of its occurrence. Patients and methods: It was a retrospective, descriptive and analytical study which is carried out at the nephrology department of Aristide Le DANTEC hospital of Dakar over a period of 60 months. Diabetics with suspected NDN diagnosis based on renal anomalie that is associated with a recent diabetes, Acute renal failure with rapid progress, Diabetic retinopathy’s absence, and Extrarenal signs (cutaneous, digestive and articular) associated with an acute renal failure. Microscopic haematuria was included. The epidemiological, clinical, biological and histological parameters were collected and analysed using the SPSS, 3.5 version software. Results: Out of 34 biopsied diabetic patients, 12 had NDN that is a prevalence of 35, 3%. The average age was 49.88 ± 4.15 years, 0.78 for the sex-ratio and the mean duration of diabetes is 12.53 ± 4.7 years. Glomerular syndrome was found in 30 patients (88.23%), vascular nephropathy syndrome in 3 patients (8.82%) and tubule-interstitial nephropathy syndrome in only one patient (2.94%). Diabetic retinopathy (DR) and microscopic haematuria (HU) respectively existed in 10 patients (34%) and 15 patients (44. 12%). The Kidney biopsy (KB) indications were renal abnormalities associated with recent diabetes, acute renal failure with rapid progress, absence of DR, extrarenal signs associated with acute renal failure and microscopic haematuria. Twenty-two patients (64.7%) had diabetic nephropathy (DN) and 12 patients (38.2%) presented a NDN. Predictive factors of NDN diagnosis were a shorter diabetes duration (P = 0.0008), high blood pressure (P = 0.0015) and absence of DR (P = 0.005). Conclusion: Our data show that kidney injury in a diabetic is not always diabetic nephropathy. The Kidney biopsy (KB) is often needed in order to adopt an effective management.

Histopathological spectrum of Adult Nephrotic Syndrome over 16 years at a Tertiary care center in Mumbai with Clinicopathological ,Electron microscopy and Immunoflurescence Correlation of Renal biopsies

Background: The pattern of diseases causing adult nephrotic syndrome varies globally as well as in India. The aim of our study was to analyze the spectrum of patients with biopsy proven nephrotic syndrome in adults over 15 years, in respect with incidence , age distribution and correlate the clinicopathological features, electron microscopy and immunofluorescence. Methods: We have evaluated and analyzed retrospectively 263 renal biopsies of adult nephrotic syndrome over a consecutive period of 16 years (January 2000 to December 2015) in our tertiary care Hospital. Result: In our study of 235 (89.35%) adequate renal biopsy cases overall male predominance was seen (M: F ratio 1.7:1) with maximum males noted in diabetic nephropathy (M: F ratio 4:1) while SLE was seen exclusively in female (M: F ratio 0:6). Minimal change disease (26.38%), followed by MPGN (16.17%) and FSGS (15.74%) were the common histopathological lesions. In 15-45 years age majority of 78.72% cases were observed with prominently histomorphological pattern as MCD( 25.10%),followed by FSGS ( 13.61%) & MPGN (13.19%). In 45-85 years age , 21.28% cases majority were of membranous glomerulonephritis (5.10%) and diabetic nephropathy (4.25%). Primary glomerular diseases accounted for 78.3% cases commonest was MCD (26.38%) and secondary glomerular diseases in 21.7% of cases, most common being amyloidosis (7.23%) Light microscopy, immunopathology findings correlated with electron microscopy findings in 79 cases (91.86%) out of 86 cases. Sample error was main reason of non correlation of EM & LM diagnosis ,especially in FSGS. Conclusion: This data analysis is essential to study the prevalence of biopsy proven renal diseases and its variation and distribution as per age .Which can improve the understanding of utility of renal biopsy for future research of renal parenchymal diseases in adults.

Clinical and pathological characteristics of non-diabetic renal disease in type 2 diabetes patients.

ABSTRACTBackgroundRenal involvement in type 2 diabetes is mainly due to diabetic nephropathy (DN). Nevertheless, a sizable proportion of diabetic patients could actually have nondiabetic renal diseases (NDRDs) or DN plus NDRDs. This study aimed to explore the pathological features of NDRD in diabetic patients and to assess the predictability of diagnosing NDRD (±DN) versus isolated DN on the basis of clinical parameters.MethodsMedical records of type 2 diabetes patients who underwent renal biopsy under suspicion of NDRD from January 2011 through November 2015 were analyzed retrospectively.ResultsA total of 101 patients were enrolled in this study. The most frequent indication for renal biopsy was recent onset of nephrotic syndrome (41%), followed by rapidly progressive renal failure (29%) and active urinary sediment (21%). On renal biopsy, 51% of patients had isolated DN, 20% had isolated NDRD and 29% had DN plus NDRD. IgA nephropathy was the most common cause of isolated NDRD, whereas acute tubular necrosis (39%) and acute interstitial nephritis (33%) were the main causes of NDRD superimposed on DN. Male gender, short-duration diabetes (<8 years), lower glycated hemoglobin and active urinary sediment (≥10 red and white blood cells per high-power field) were independent predictors of NDRD according to multiple logistic regression analysis.ConclusionsJudicious use of renal biopsy revealed NDRD (±DN) in nearly half of type 2 diabetes patients with atypical renal presentation, especially in male patients with well-controlled diabetes, those who have had diabetes for a short duration and those with active urinary sediment.

Influence of renal biopsy results on the management of small kidney cancers in older patients: Results from a population-based cohort

Background and objectiveSmall kidney cancers are a heterogeneous group with varying malignant potential. Pathologic information obtained from a renal biopsy may guide decision-making for small kidney cancers. We sought to assess the effect of pathologic information from renal biopsy on the nonsurgical management of small kidney cancers in a population-based cohort of patients over 65 years of age. MethodsIn the Surveillance, Epidemiology and End Results-Medicare dataset, we identified patients ≥66 years diagnosed with a kidney cancer<4cm between 2002 and 2011. Diagnostic biopsy was defined by a Medicare claim within 1 month prior through 6 months following cancer diagnosis or before surgery. Nonsurgical management was defined by the absence of a claim for partial or radical nephrectomy or tumor ablation in the first 6 months following diagnosis. The relationship between patient and tumor characteristics and the likelihood of nonsurgical management by receipt of diagnostic biopsy was assessed by multivariable logistic regression models. ResultsFrom 8,933 patients, 2,782 (31%) had a diagnostic renal biopsy of whom 616 (22%) were managed nonsurgically. Controlling for patient, disease, and provider specialty, biopsy was associated with nonsurgical management (adjusted odds ratio = 1.61, 95% Cl: 1.43–1.82) in patients with low-grade tumors but also with more aggressive histology (clear cell renal cell carcinoma). Older age (85+) and geographic region were significantly associated with greater odds of diagnostic biopsy. Patients whose initial renal tumor diagnosis was made by a urologist (vs. other type of provider) were less likely to receive a biopsy (adjust odds ratio = 0.73, 95% Cl: 0.60–0.89). ConclusionsAlthough the use of renal biopsy has increased over time and is associated with the use of nonsurgical management of small kidney cancers, the use of the pathologic findings remains limited. Further advances, particularly with prognostic markers, are necessary before renal biopsy can be routinely implemented for treatment decision-making for small kidney cancers.

Nondiabetic renal disease in type 2 diabetes mellitus

Background and Objectives: The prevalence of nondiabetic renal disease (NDRD) in those with type 2 diabetes mellitus (T2DM) is common worldwide; however, data from India are limited. Materials and Methods: This study included participants with T2DM who underwent renal biopsy with suspicion of NDRD from September 2009 to August 2016. Results: Seventy-one participants (males: 47 [66.2%] and females: 24 [33.8%]) of T2DM with mean age and standard deviation of 52.93 ± 12.56 years were included in the study. The indications for renal biopsy included acute on chronic renal failure in 35.2% (25), nephrotic syndrome in 31% (22), acute renal failure in 14.1% (10), nephritic syndrome in 14.1% (10), and others in 5.6% (4) of participants. The prevalence rates of NDRD, diabetic nephropathy (DN), and DN with NDRD were 50.71% (36), 28.16% (20), and 21.13% (15), respectively. Among the participants with NDRD, 69.44% (25) had primary glomerular diseases (PGDs), 16.67% (6) had tubulointerstitial diseases (TIDs), and 13.89% (5) had secondary glomerular diseases (SGDs). IgA nephropathy was the most common of PGDs affecting 28% (7), followed by postinfective glomerulonephritis (PIGN) in 20% (5), membranous nephropathy in 16% (4), focal segmental glomerulosclerosis in 12% (3), and miscellaneous lesions in 24% (10). Acute interstitial nephritis and primary amyloidosis were the most common of TIDs and SGDs, respectively. Among the patients with combination of DN with NDRD, 53.33% (8) were TIDs and 46.67% (7) had glomerular diseases. Acute tubular injury/necrosis and PIGN were the most common of TIDs and glomerular disease, respectively. The figures in brackets representing number of patients. Conclusions: The majority of the participants with T2DM had NDRD either alone or in combination with DN in the study, underlining the utility of renal biopsy for their diagnoses in those with appropriate indication. Wide spectrum of PGDs, TIDs, and SGDs was found in the study.

Predictive factors for non-diabetic nephropathy in diabetic patients. The utility of renal biopsy

Background and objectivesDiabetic 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 methodsA descriptive, retrospective study of kidney biopsies of diabetics between 1990 and 2013 in our centre. Results110 patients were included in the study: 87 men (79%), mean age 62 years (50–74), mean serum creatinine 2.6mg/dl (0.9–4.3) and proteinuria 3.5g/24hours (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/24hours (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. ConclusionsThe 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.