Long-term Kidney Outcomes Research Articles

Kidney disease and reproductive health.

Understanding the relationship between reproductive health and kidney function is important to provide holistic care for people living with kidney disease. Chronic kidney disease (CKD) has negative impacts on both male and female fertility owing to factors including inflammation, hormonal dysregulation, reduced ovarian reserve, reduced sperm quality and sexual dysfunction. However, pregnancy is achievable for most cisgender women with kidney disease, including kidney transplant recipients and patients on dialysis. CKD in pregnancy is associated with health risks to the mother and child, including increased risk of progression of kidney disease, hypertensive complications of pregnancy, and neonatal complications including fetal growth restriction, preterm birth and stillbirth. However, with appropriate pre-pregnancy counselling, fertility assessment and support, health optimization, and evidence-based antenatal care, the majority of patients will achieve a good outcome. Medication safety should be reviewed before and during pregnancy and lactation, weighing the risk of disease flare against potential adverse effects on the offspring. Important areas for further research include the optimal timing of delivery and the short- and long-term cardiovascular and renal impacts of pregnancy in patients with CKD, as well as long-term kidney and cardiovascular outcomes in their offspring.

Long-Term Kidney Outcomes after Pediatric Acute Kidney Injury: Future Studies Need to Explore Further

Long-Term Kidney Outcomes after Pediatric Acute Kidney Injury: Future Studies Need to Explore Further

Kidney complications in children with bronchopulmonary dysplasia.

To describe kidney outcomes in a cohort of children with bronchopulmonary dysplasia (BPD). We assessed short-term (acute kidney injury defined using neonatal KDIGO criteria) and long-term kidney outcomes, including chronic kidney disease (defined as a GFR < 90 ml/min/1.73 m2), albuminuria, and hypertension in a single-center retrospective cohort of children with BPD born between 2010 and 2020. 309 (38.8%) of 797 children included in the cohort had acute kidney injury (AKI) during their NICU admission. Kidney specific follow-up evaluation was infrequent in this cohort; 52.4% of patients had serum creatinine testing and 31.5% had a urinalysis performed after discharge. 163 (32.0%) of 510 patients with long-term data had CKD, which occurred at a median age of 2.2 years. An abnormal eGFR occurred in 31.7%, proteinuria in 12.5% and hypertension in 15.2%. Children with BPD had high frequencies of AKI and CKD. While the retrospective nature and single-center convenience cohort design limit generalizability, our findings suggest that children with BPD should be carefully monitored for short- and long-term kidney outcomes, including CKD. Children with bronchopulmonary dysplasia (BPD) may have a higher likelihood of both acute and chronic kidney complications than currently recognized. Kidney outcomes in children with BPD is an area that remains underexplored. To our knowledge, this is the first study exploring the prevalence of CKD in a cohort of children with BPD. Our findings suggest children with BPD have high rates of kidney complications in early childhood. Increased attention should be placed on monitoring children with BPD for both short- and long-term kidney outcomes.

Long-Term Kidney Outcome of Lupus Nephritis by Renal Response Status

IntroductionLimited evidence exists that clinical trial treatment response criteria predict long-term outcomes in Asian patients with lupus nephritis (LN). MethodsThis retrospective analysis of prospectively collected data from the Hong Kong Queen Mary Hospital Cohort categorized adults with biopsy-proven LN (Class III, IV, V, or mixed [III±V, IV±V]) after standard treatment for 2 years (2Y) post biopsy and immunosuppression induction according to modified primary efficacy renal response (mPERR: estimated glomerular filtration rate [eGFR] ≥60 ml/min/1.73 m2 or ≤20% below biopsy value AND urine protein:creatinine ratio [uPCR] ≤0.7) and modified complete renal response (mCRR; eGFR ≥90 ml/min/1.73 m2 or ≤10% below biopsy value AND uPCR ≤0.5). Associations between 2Y mPERR/mCRR status and long-term kidney survival and mild chronic kidney disease (CKD) or worse (Stage ≥3) were assessed. ResultsOf the 176 Chinese patients, 64.2% achieved mPERR and 43.8% achieved mCRR at 2Y post biopsy. After mean follow-up of 15.3 years, significantly higher proportions of mPERR and mCRR responders versus non-responders achieved long-term kidney survival (mPERR: 85.8% vs 71.4%; p=0.029; mCRR: 92.2% vs 71.7%; p<0.001). mPERR and mCRR achievement was associated with adjusted risk reductions for kidney non-survival of 60% (p=0.034) and 86% (p<0.001), respectively. Adjusted risk for mild CKD or worse (Stage ≥3) was 82% (p=0.013) and 87% (p=0.012) lower for mPERR and mCRR responders, respectively, versus non-responders. ConclusionsIn Chinese patients with LN, mPERR and mCRR at 2Y post biopsy predict superior long-term kidney outcomes and lower CKD progression risk.

Long-Term Kidney Outcomes in ANCA-Associated Vasculitis in a Mexican Hispanic Cohort

Long-Term Kidney Outcomes in ANCA-Associated Vasculitis in a Mexican Hispanic Cohort

Long-Term Kidney Outcomes in Children and Adolescents with Hypertension

Long-Term Kidney Outcomes in Children and Adolescents with Hypertension

Long-Term Kidney Outcomes in Pediatric Renal Vein Thrombosis

Long-Term Kidney Outcomes in Pediatric Renal Vein Thrombosis

Cardiac and kidney outcomes after sacubitril-valsartan therapy: recovery of cardiac function relative to kidney function decline.

Sacubitril-valsartan reduces the risk of cardiovascular mortality among patients with heart failure with reduced ejection fraction (HFrEF). However, its long-term protective effects on cardiac function with concurrent acute kidney injury (AKI) remain unclear. This study investigated the recovery of cardiac function relative to kidney function decline. A total of 512 patients with HFrEF who started sacubitril-valsartan or valsartan treatment were enrolled in cohort 1. Additionally, patients who experienced AKI and underwent follow-up transthoracic echocardiography were enrolled in cohort 2. In cohort 1, short- and long-term kidney outcomes were analyzed. For cohort 2, changes in cardiac function in relation to changes in kidney function after drug initiation were analyzed. The mean age of the patients was 68.3 ± 15.1 years, and 57.4% of the patients were male. AKI occurred in 15.9% of the sacubitril-valsartan group and 12.5% of the valsartan group. After AKI, 78.4% of patients in the sacubitril-valsartan group and 71.4% of those in the valsartan group underwent recovery. Furthermore, cardiovascular outcomes in patients who developed AKI after drug initiation were analyzed in cohort 2. The sacubitril-valsartan group showed a greater improvement in cardiac function compared with the valsartan group (12.4% ± 15.4% vs. 1.4% ± 5.7%, p = 0.046). The ratio of deltas of cardiac and kidney function in the sacubitril-valsartan and valsartan groups were -1.76 ± 2.58 and -0.20 ± 0.58, respectively (p = 0.03). Patients with HFrEF treated with sacubitril-valsartan exhibited significant improvements in cardiovascular outcomes despite AKI.

Prognosis of IgA nephropathy patient with proteinuria remission by supportive therapy: cohort from screening failed Chinese patients in TESTING study

Background During the run-in phase of the TESTING study, approximately half of patients with IgA nephropathy (IgAN) were excluded due to proteinuria below 1 g/24 h after intensive supportive therapy. The long-term prognosis of these patients needs further investigation. Methods 112 screening failed patients in the TESTING study from 10 centers in China were enrolled in this retrospective study. The prognosis of 88 patients, who were excluded because of proteinuria below 1 g/24 h, was analyzed by Landmark Kaplan-Meier analysis. The composite kidney endpoint was defined by a ≥ 50% reduction in eGFR, ESKD (eGFR <15 mL/min per 1.73 m2), chronic dialysis for at least 6 months, or renal transplantation. Results In total, 88 patients were excluded due to proteinuria less than 1 g/24 h. During the follow-up, 73/88 (83.0%) patients received renin-angiotensin system blocker. 72/88 (81.8%) had stable proteinuria remission and did not receive immunosuppressive therapy (IST), and 16/88 (18.2%) received IST because of a relapse of proteinuria. Landmark Kaplan–Meier analysis revealed that, the kidney survival from dialysis or composite kidney outcome of these excluded patients with IST was similar to those without IST during the early stages of follow-up (dialysis, before 60 months, p = 0.778; composite kidney outcome, before 48 months, p = 0.862); whereas the risk for dialysis of patients receiving IST was significantly higher than those without IST after 60 months (OR = 11.3, p = 0.03). Similarly, the risk for the composite kidney outcome of patients receiving IST was also significantly higher than those without IST after 48 months (OR = 5.92, p = 0.029). Conclusions IgAN patients who maintained a persistent remission of proteinuria after intensive supportive therapy had a much better long-term kidney outcome than those who experienced a relapse of proteinuria and needed IST.

Renal vascular lesions in childhood-onset lupus nephritis.

This study aimed to determine the clinical significance of renal vascular lesions (RVLs) in childhood-onset lupus nephritis (cLN). We retrospectively reviewed all children with biopsy-proven cLN between 2004-2020 to evaluate the prevalence of RVLs on kidney biopsy and its associated factors and long-term outcomes. The composite kidney outcome was defined as advanced chronic kidney disease (CKD) stage 3-5, kidney failure and death. 107 biopsies from 84 Chinese patients were analysed. RVLs were observed in 19 patients (22.6%), including non-inflammatory necrotizing vasculopathy (NNV, n = 6), thrombotic microangiopathy (TMA, n = 4), arterial sclerosis (AS, n = 3), concurrent NNV with AS (n = 4), concurrent NNV with TMA (n = 1) and concurrent true renal vasculitis with AS (n = 1). The presence of RVLs was associated with lower estimated glomerular filtration rate (eGFR) (66.9 ± 40.3 vs. 95.6 ± 39.4ml/min/1.73m2, p = 0.005), haemoglobin level (9.1 ± 1.9 vs. 10.4 ± 1.9g/dL, p = 0.008) and platelet count (150.1 ± 96.4 vs. 217.2 ± 104.8 × 109/L, p = 0.01). LN classes and activity/chronicity indices were similar. Patients with RVLs had poorer composite kidney outcomes, though not reaching statistical significance (log-rank test, p = 0.06). The presence of NNV was associated with inferior survival free from composite kidney outcome (log-rank test, p = 0.0018), compared to other forms of RVLs and those without RVLs. Univariate analysis revealed NNV (HR 7.08, 95% CI 1.67-30.03) was predictive of composite kidney outcome. RVLs are present in one-fifth of cLN patients and are associated with severe presentation. NNV is associated with worse long-term kidney outcome. Routine evaluation of RVLs is warranted and should be incorporated into future classification criteria.

Long-Term Kidney Outcomes in Children with Posterior Urethral Valves: A Population-Based Cohort Study.

Posterior urethral valves represent the most common cause of lower urinary tract obstruction in male infants (∼1/4000 live births). Long-term kidney outcomes of posterior urethral valves remain uncertain. We aimed to determine the time-varying risk of major adverse kidney events (MAKE) following children with posterior urethral valves into adulthood. A population-based retrospective cohort study of all males (<2 years) diagnosed with posterior urethral valves between 1991-2021 in Ontario, Canada. Comparator cohorts were: 1) male general population and 2) male pyeloplasty patients (both <2 years). The primary outcome was MAKE (death, long-term kidney replacement therapy [dialysis or kidney transplant], or chronic kidney disease). Time-to-MAKE was analyzed using multivariable-adjusted Cox proportional hazards models. We censored for provincial emigration, or administrative censoring (March 31, 2022). We included 727 children with posterior urethral valves, 855 pyeloplasty comparators, and 1,013,052 general population comparators. Median follow-up time was 16.6 years (Q1-3 8.6-24.5) overall. Throughout follow-up, 32% of children with posterior urethral valves developed MAKE vs. 1% of the general population and 6% of pyeloplasty comparators. Their adjusted hazard ratio for MAKE was 36.6 (95%CI 31.6-42.4) vs. the general population. The risk of developing MAKE declined over the first 5 years after posterior urethral valves diagnosis but remained elevated for >30-year follow-up. Children with posterior urethral valves were also at higher risk of death, chronic kidney disease, long-term kidney replacement therapy, hypertension, and acute kidney injury than general population or pyeloplasty comparators. Children with posterior urethral valves are at higher risk of adverse long-term kidney outcomes well into adulthood.

Podocyte density as a predictor of long-term kidney outcome in obesity-related glomerulopathy

Glomerulomegaly and focal segmental glomerulosclerosis are histopathological hallmarks of obesity-related glomerulopathy (ORG). Podocyte injury and subsequent depletion are regarded as key processes in the development of these glomerular lesions in patients with ORG, but their impact on long-term kidney outcome is undetermined. Here, we correlated clinicopathological findings and podocyte depletion retrospectively in patients with ORG. Relative (podocyte density) and absolute (podocyte number per glomerulus) measures of podocyte depletion were estimated using model-based stereology in 46 patients with ORG. The combined endpoint of kidney outcomes was defined as a 30% decline in estimated glomerular filtration rate (eGFR) or kidney failure. Patients with lower podocyte density were predominantly male and had larger body surface area, greater proteinuria, fewer non-sclerotic glomeruli, larger glomeruli and higher single-nephron eGFR. During a median follow-up of 4.1 years, 18 (39%) patients reached endpoint. Kidney survival in patients with lower podocyte density was significantly worse than in patients with higher podocyte density. However, there was no difference in kidney survival between patient groups based on podocyte number per glomerulus. Cox hazard analysis showed that podocyte density, but not podocyte number per glomerulus, was associated with the kidney outcomes after adjustment for clinicopathological confounders. Thus, our study demonstrates that a relative depletion of podocytes better predicts long-term kidney outcomes than does absolute depletion of podocytes. Hence, the findings implicate mismatch between glomerular enlargement and podocyte number as a crucial determinant of disease progression in ORG.

Long-Term Kidney Outcomes after Pediatric Acute Kidney Injury.

Acute kidney injury (AKI) is common in hospitalized children. Pediatric AKI receiving acute kidney replacement therapy (KRT) is associated with long-term chronic kidney disease (CKD), hypertension, and death. We aim to determine the outcomes after AKI in children who did not receive acute KRT, since these remain uncertain. Retrospective cohort study of all hospitalized children (0-18 years) surviving AKI without acute KRT between 1996-2020 in Ontario, Canada, identified by validated diagnostic codes in provincial administrative health databases. Children with prior KRT, CKD, or AKI were excluded. Cases were matched with up to four hospitalized comparators without AKI by age, neonatal status, sex, intensive care unit admission, cardiac surgery, malignancy, hypertension, hospitalization era, and a propensity score for AKI. Patients were followed until death, provincial emigration, or censoring in March 2021. The primary outcome was long-term major adverse kidney events (MAKE-LT; a composite of all-cause mortality, long-term KRT, or incident CKD). We matched 4,173 pediatric AKI survivors with 16,337 hospitalized comparators. Baseline covariates were well-balanced following propensity score matching. During median 9.7-year follow-up, 18% of AKI survivors developed MAKE-LT vs. 5% of hospitalized comparators (hazard ratio [HR] 4.0, 95% confidence interval [CI] 3.6-4.4). AKI survivors had higher rates of long-term KRT (2% vs. <1%; HR 11.7, 95%CI 7.5-18.4), incident CKD (16% vs. 2%; HR 7.9, 95%CI 6.9-9.1), incident hypertension (17% vs. 8%; HR 2.3, 95%CI 2.1-2.6), and AKI during subsequent hospitalization (6% vs. 2%; HR 3.7, 95%CI 3.1-4.5), but no difference in all-cause mortality (3% vs. 3%; HR 0.9, 95%CI 0.7-1.1). Children surviving AKI without acute KRT were at higher long-term risk of CKD, long-term KRT, hypertension, and subsequent AKI vs. hospitalized comparators.

Advocating for the inclusion of kidney health outcomes in neonatal research: best practice recommendations by the Neonatal Kidney Collaborative.

Acute kidney injury (AKI) occurs in nearly 30% of sick neonates. Chronic kidney disease (CKD) can be detected in certain populations of sick neonates as early as 2 years. AKI is often part of a multisystem syndrome that negatively impacts developing organs resulting in short- and long-term pulmonary, neurodevelopmental, and cardiovascular morbidities. It is critical to incorporate kidney-related data into neonatal clinical trials in a uniform manner to better understand how neonatal AKI or CKD could affect an outcome of interest. Here, we provide expert opinion recommendations and rationales to support the inclusion of short- and long-term neonatal kidney outcomes using a tiered approach based on study design: (1) observational studies (prospective or retrospective) limited to data available within a center's standard practice, (2) observational studies involving prospective data collection where prespecified kidney outcomes are included in the design, (3) interventional studies with non-nephrotoxic agents, and (4) interventional studies with known nephrotoxic agents. We also provide recommendations for biospecimen collection to facilitate ancillary kidney specific research initiatives. This approach balances the costs of AKI and CKD ascertainment with knowledge gained. We advocate that kidney outcomes be included routinely in neonatal clinical study design. Consistent incorporation of kidney outcomes across studies will increase our knowledge of neonatal morbidity.

Long-Term Kidney Outcomes Among Children With STEC-HUS

Long-Term Kidney Outcomes Among Children With STEC-HUS

Early reduction in albuminuria is associated with a steeper 'dip' in initial estimated glomerular filtration rate but favourable long-term kidney outcomes in people with diabetes receiving sodium-glucose cotransporter-2 inhibitors.

To assess if early change in albuminuria was linked to an initial change in estimated glomerular filtration rate (eGFR) and long-term kidney outcomes in people with type 2 diabetes (T2D) receiving sodium-glucose cotransporter-2 (SGLT2) inhibitors. Using a medical database from a multicentre healthcare institute in Taiwan, we retrospectively enrolled 8310 people receiving SGLT2 inhibitors from 1 June 2016 to 31 December 2021. We compared the risks of initial eGFR decline, major adverse renal events (MARE; >50% eGFR reduction or development of end-stage kidney disease), major adverse cardiovascular events (MACE), or hospitalization for heart failure (HHF) using a Cox proportional hazards model. In all, 36.8% (n = 3062) experienced a >30% decrease, 21.0% (n = 1743) experienced a 0%-30% decrease, 14.4% (n = 1199) experienced a 0%-30% increase, and 27.7% (n = 2306) experienced a >30% increase in urine albumin-to-creatine ratio (UACR) after 3 months of SGLT2 inhibitor treatment. Greater acute eGFR decline at 3 months correlated with greater UACR reduction: -3.6 ± 10.9, -2.0 ± 9.5, -1.1 ± 8.6, and -0.3 ± 9.7 mL/min/1.73 m2 for the respective UACR change groups (p < 0.001). Over a median of 29.0 months, >30% UACR decline was associated with a higher risk of >30% initial eGFR decline (hazard ratio [HR] 2.68, 95% confidence interval [CI] 1.61-4.47]), a lower risk of MARE (HR 0.66, 95% CI 0.48-0.89), and a comparable risk of MACE or HHF after multivariate adjustment (p < 0.05). The nonlinear analysis showed early UACR decline was linked to a lower risk of MARE but a higher risk of initial steep eGFR decline of >30%. Physicians should be vigilant for the potential adverse effects of abrupt eGFR dipping associated with a profound reduction in UACR, despite the favourable long-term kidney outcomes in the population with T2D receiving SGLT2 inhibitor treatment.

Long-term kidney outcomes in patients with permanent hypoparathyroidism after total thyroidectomy for benign disease: A population-based study

BackgroundPermanent hypoparathyroidism is a significant complication after total thyroidectomy. This study aimed to evaluate the long-term impact of postoperative permanent hypoparathyroidism on kidney outcomes. MethodsData of patients undergoing total thyroidectomy from 1999 to 2014 were retrieved. The estimated glomerular filtration rate was determined from serum creatinine results. Permanent hypoparathyroidism was defined as requiring oral calcium and vitamin D supplements postoperatively for at least 6 months. The primary outcome was a sustained decline in the estimated glomerular filtration rate from baseline by ≥50%. Secondary outcomes were end-stage kidney disease (a composite of sustained estimated glomerular filtration rate <15 mL/min/1.73 m2, need for dialysis, and kidney transplantation) and rate of estimated glomerular filtration rate decline. Patients with and without permanent hypoparathyroidism were compared. Multivariable Cox regression analysis was performed to identify independent risk factors for sustained estimated glomerular filtration rate decline by ≥50%. ResultsIn total, 3,245 patients were eligible for analysis; 418 patients (12.9%) had permanent hypoparathyroidism. Upon median follow-up of 11.6 years, more patients with permanent hypoparathyroidism had a sustained decline in estimated glomerular filtration rate from baseline by ≥50% compared to those without (15.6% vs 6.9%, P < .001). Similar findings were obtained on Kaplan–Meier analysis (P < .001). Permanent hypoparathyroidism was an independent risk factor for sustained estimated glomerular filtration rate decline by ≥50% (adjusted hazard ratio 2.77, P < .001). Other risk factors included age, preoperative estimated glomerular filtration rate <60 mL/min/1.73m2, and diabetes mellitus. Patients with permanent hypoparathyroidism had a more rapid estimated glomerular filtration rate decline (–1.60 vs –0.70 mL/min/1.73 m2/year, difference –0.91 mL/min/1.73m2/year, P < .001). ConclusionPatients with postsurgical permanent hypoparathyroidism were at greater risk of renal impairment. Further research is warranted to improve the identification and preservation of parathyroid glands during thyroidectomy to minimize patient morbidity.

Long-term kidney outcomes of semaglutide in obesity and cardiovascular disease in the SELECT trial

The SELECT trial previously reported a 20% reduction in major adverse cardiovascular events with semaglutide (n = 8,803) versus placebo (n = 8,801) in patients with overweight/obesity and established cardiovascular disease, without diabetes. In the present study, we examined the effect of once-weekly semaglutide 2.4 mg on kidney outcomes in the SELECT trial. The incidence of the pre-specified main composite kidney endpoint (death from kidney disease, initiation of chronic kidney replacement therapy, onset of persistent estimated glomerular filtration rate (eGFR) < 15 ml min−1 1.73 m−2, persistent ≥50% reduction in eGFR or onset of persistent macroalbuminuria) was lower with semaglutide (1.8%) versus placebo (2.2%): hazard ratio (HR) = 0.78; 95% confidence interval (CI) 0.63, 0.96; P = 0.02. The treatment benefit at 104 weeks for eGFR was 0.75 ml min−1 1.73 m−2 (95% CI 0.43, 1.06; P < 0.001) overall and 2.19 ml min−1 1.73 m−2 (95% CI 1.00, 3.38; P < 0.001) in patients with baseline eGFR <60 ml min−1 1.73 m−2. These results suggest a benefit of semaglutide on kidney outcomes in individuals with overweight/obesity, without diabetes.ClinicalTrials.gov identifier: NCT03574597.

#1495 5 and 10 year kidney outcomes in acute interstitial nephritis: a retrospective single-centre cohort study

Abstract Background and Aims Acute interstitial nephritis (AIN) is a common cause of acute kidney injury (AKI), histologically characterized by an interstitial inflammatory cell infiltrate. Data regarding long term kidney outcomes is lacking. We performed a retrospective cohort study to evaluate the long-term kidney and mortality outcomes in patients with biopsy-proven AIN between 2011-2018. Method We serve as a tertiary referral centre and sole nephrology provider for a population of over 650,000 people. We identified biopsy-proven AIN cases from the years 2011-2018 from our pathology database. Demographic data, creatinine, eGFR (calculated using CKD-EPI 2021 formula), dialysis and mortality data were collected from our electronic medical record. Ethical approval was obtained. Results Between 2011 – 2018, 576 native kidney biopsies were performed in our centre. 66 (11.5%) cases had pathologically confirmed AIN as the primary kidney diagnosis. Long-term outcome data was available for 90.9% (60). The median age at time of biopsy was 52.5 years (IQR 41.5 - 68.3). 68% of patients were male. The aetiology of AIN was medication in 42%, autoimmune in 15% and infection-associated in 3%. Of the cases of drug-induced AIN the predominant culprits agents were non-steroidal anti-inflammatories 28%, proton pump inhibitors in 24%, antibiotics 20%, with other medications in 8%. The median eGFR at the time of biopsy was 13.6 (IQR 7.9 -25.4) mls/min/1.73 m2. The median eGFR at year 1 was 47.8 (IQR 30.7 - 72.7) mls/min/1.73 m2, 54.4 (IQR 31.2 -79.6) mls/min/1.73 m2 at year 5 and 69.4 (IQR 19.9 - 86.1) mls/min/1.73 m2 at year 10. See Table 1 for results. At one year 64.3% of cases had eGFR &amp;lt; 60 mls/min/1.73 m2 (CKD III or higher). Interestingly the rate of CKD was lower at years 5 and 10 (54.7% and 50% respectively). GFR &amp;lt;30 mls/min (CKD IV or higher) were present in 25% at year 1, 26% at year 5 and 37% at year 10. 23% (14/60) people had dialysis-requiring AKI at the time of biopsy. Of these 21.4% (3) remained dialysis dependent at one year. In this group, no additional cases of ESKD were seen between years 1 through 5, one additional case of ESKD occurred by year 10. A composite outcome of kidney failure (GFR &amp;lt;15, dialysis or kidney transplantation) occurred in 48.2% at year 1, 54.7% at year 5 and 56.2% at year 10. Mortality data was available on 58 patients. 18.9% (11) people had died at 10 years follow-up. 8 out of the 11 deaths were within 5 years, 2 of which were within 1 year of diagnosis. Conclusion In this single centre study, kidney failure occurred in 48% of people at 10 years of follow up. 78% of dialysis-requiring cases recover independent renal function.

#1297 Approaches to renal response assessment in rare monoclonal immunoglobulin related glomerulopathies

Abstract Background and Aims AL-amyloidosis (AL) and monoclonal immunoglobulin (MIg) deposition disease are common types of MIg-related glomerulopathies (MIgG) and are well-studied including approaches to treatment and hematological and renal responses (RR) assessment. Other rare MIgG comprise very diverse patterns of glomerular injury e.g. proliferative glomerulonephritis with MIg deposition (PGNMID), C3-glomerulopathy, fibrillary glomerulonephritis etc. Although RR defined as decrease in 24 h proteinuria by 30% without kidney function decline was validated only for renal AL it is widely used for MIg deposition disease and rare MIgG without validation. Nevertheless, the best approach to RR assessment in rare MIgG is still unclear. To shed some light on this problem we performed this study. Method We retrospectively analyzed 31 patients with rare MIgG who were treated with clone-specific treatment and had available follow-up (FUP) ≥6 months (mo). The following morphological patterns were diagnosed: PGNMID (n = 9), C3-glomerulopathy (n = 9), thrombotic microangiopathy (n = 5), cryoglobulinemic glomerulonephritis (n = 3), fibrillary glomerulonephritis (n = 3), immunotactoid glomerulonephritis (n = 1) and membranous nephropathy (n = 1). Patients’ baseline parameters are shown on Fig. 1 as well as treatment modalities. Hematological response defined according to currently accepted criteria is demonstrated on Fig. 1. We evaluated two approaches to the RR assessment: 1) at least partial renal response (PR) defined as 24 h proteinuria decreased by 50% from the baseline and &amp;lt;3.5 g, and 2) according to Palladini's criteria for AL (AL-RR) i.e. 24 h proteinuria decreased by 30% from the baseline or &amp;lt;0.5 g. Both RR were considered as achieved only in the absence of estimated glomerular filtration rate (eGFR) decline &amp;gt;25%. Time points for RR assessment were 6, 12 and 24 mo from the clone-specific treatment initiation. Renal outcome was estimated as initiation of renal replacement therapy or eGFR &amp;lt;15 ml/min/1.73 m2 at the end of follow-up. Death-censored renal survival was analyzed by the Kaplan-Meier method. Cox regression analysis was applied to determine which RR was independently associated with long-term kidney outcome. P-value was assumed at &amp;lt;0.05. Median FUP was 19 (7; 50) mo. FUP ≥12 and ≥24 mo were available in 26 and 17 patients, respectively. Results Total number of patients who achieved AL-RR at any RR assessment time point was 22 (71%). At 6, 12 and 24 mo the achievement of AL-RR was registered in 17, 16 and 10 patients, respectively. PR cumulatively was achieved in 19 (61%) patients: at time points of 6, 12, and 24 mo it was registered in 14, 14 and 9 cases, respectively. The 5-year cumulative renal survival in those who had AL-RR was better than in not responders (Fig. 2A). Patients who ever achieved PR had better cumulative renal survival compared with patients with no renal remission (Fig. 2B). In univariate Cox regression analysis the achievement of AL-RR (Exp(β) 0.158 (95% CI 0.03; 0.819)) was associated with renal outcome as well as the achievement of PR (Exp(β) 0.074 (95% CI 0.09; 0.626)). In multivariate Cox regression model adjusted for eGFR at the time of kidney biopsy AL-RR vs no response was estimated as an independent predictor of renal long-term prognosis (Exp(β) 0.082 (95% CI 0.009; 0.725)) as well as eGFR (Exp(β) 0.89 (95% CI 0.821; 0.985)). The only independent predictor of renal outcome in the model including eGFR at the time of kidney biopsy (Exp(β) 0.85 (95% CI 0.72; 0.99), p = 0.05) was PR (Exp(β) 0.011 (95% CI 0; 0.547), p = 0.021). Conclusion The classical concept of complete and partial renal remission seems to be more appropriate for rare MIgG and requires further validation studies.