Epidemiology of Immune-Mediated Glomerulopathies before and after SARS-CoV-2 Vaccination: A Tertiary Referral Hospital Experience

BACKGROUND

Vaccination is a known trigger for the appearance of immune-mediated glomerulopathies (IMG). The appearance of IMG after SARS-CoV-2 vaccination with suspected causality has been described. Our aim is to analyze the incidence of IMG flares before and after SARS-CoV-2 vaccination in our center.

METHODS

All persons with native kidney biopsy (KB) from January 2019 to March 2022 in our center were included in the study. We compared the incidence of IMG before and after the start of vaccination. We also collected information about whether the patients had received a SARS-CoV-2 vaccine or have suffered from COVID in the six weeks before the IMG. We also evaluated the analytical characteristics of the outbreaks.

RESULTS

A total of 386 KB were studied. Of them, 86/218 (39.4%) were IMG performed pre- and 85/168 (50.6%) post-SV (029). The incidence of idiopathic nephrotic syndrome (INS), studied separately, was also significantly increased post-vaccination (n = 18 (10.7%)) compared to pre-vaccination (n = 11 (5%)) (p = 0.036). There were no differences in the incidence of vasculitis or IgA nephropathy. Up to 17 (20%) flares occurred 6 weeks before SARS-CoV-2 vaccination and only 2 (2.4%) within the first 6 weeks after SARS-CoV-2 infection. Within those 17 flares, the most common diagnosis was IgAN (n = 5 (29.4%)); a total of 14 (82.4%) received an mRNA vaccine and 9 (52.9%) took place after the 1st vaccine dose. There were 13 cases of minimal change disease (MCD) with debut/recurrence pre-SV and 20 MCD with debut/recurrence post-SV (p = 0.002).

CONCLUSIONS

The incidence of IMG, INS and MCD flares in our center increased significantly after SARS-CoV-2 vaccination. Importantly, 20% of IMG flares took place within the first 6 weeks after receiving a vaccine dose, with the first dose being the riskiest one and IgAN the most frequent diagnosis.

Endothelin Receptor Antagonists in Kidney Disease

Endothelin (ET) is found to be increased in kidney disease secondary to hyperglycaemia, hypertension, acidosis, and the presence of insulin or proinflammatory cytokines. In this context, ET, via the endothelin receptor type A (ET_A) activation, causes sustained vasoconstriction of the afferent arterioles that produces deleterious effects such as hyperfiltration, podocyte damage, proteinuria and, eventually, GFR decline. Therefore, endothelin receptor antagonists (ERAs) have been proposed as a therapeutic strategy to reduce proteinuria and slow the progression of kidney disease. Preclinical and clinical evidence has revealed that the administration of ERAs reduces kidney fibrosis, inflammation and proteinuria. Currently, the efficacy of many ERAs to treat kidney disease is being tested in randomized controlled trials; however, some of these, such as avosentan and atrasentan, were not commercialized due to the adverse events related to their use. Therefore, to take advantage of the protective properties of the ERAs, the use of ET_A receptor-specific antagonists and/or combining them with sodium-glucose cotransporter 2 inhibitors (SGLT2i) has been proposed to prevent oedemas, the main ERAs-related deleterious effect. The use of a dual angiotensin-II type 1/endothelin receptor blocker (sparsentan) is also being evaluated to treat kidney disease. Here, we reviewed the main ERAs developed and the preclinical and clinical evidence of their kidney-protective effects. Additionally, we provided an overview of new strategies that have been proposed to integrate ERAs in kidney disease treatment.

Bioremoval of copper by filamentous fungi isolated from contaminated soils of Puchuncaví-Ventanas Central Chile

Pollution represents a high risk to plants, animals, and human beings, causing an imbalance and affecting the environment. Soil is considered a universal sink, containing the highest load of environmental pollution. Puchuncaví-Ventanas sector, decreed as a saturated contamination zone in 1993, is considered one of the most affected areas by industrial pollution and belongs to one of the 5 sacrifice zones of Chile. The localities of Puchuncaví and Ventanas have heavy metal pollution levels that exceed up to 99% of the limits allowed by Canadian standards. The objective of this study was to characterize heavy metal tolerance and removal potential of filamentous fungi isolated from polluted soils for their use in decontamination systems and in situ soil improvement. Six fungal strains were selected based on their tolerance and a high capability to accumulate heavy metals, achieving copper bioaccumulation of 84% (Mortierella sp. strain LG01), 49% (Clonostachys sp. strain CQ23) and 48-77.5% (Trichoderma sp. strain LM01A). Trichoderma sp. strain LM01A was able to remove 41% of copper from contaminated soil under ex situ conditions. Some fungal strains belong to beneficial fungal genera, which are used as bioproducts in agriculture. The results of this study highlighted the use of Trichoderma sp. in soils contaminated, which may be of special interest in agriculture due to the large amounts of copper sulfate still applied as a pesticide in Chile and the world.

Corrigendum: Enteric Budesonide in Transplant and Native IgA Nephropathy: Real-World Clinical Practice

[This corrects the article DOI: 10.3389/ti.2022.10693.].

Enhanced Cardiorenal Protective Effects of Combining SGLT2 Inhibition, Endothelin Receptor Antagonism and RAS Blockade in Type 2 Diabetic Mice

Treatments with sodium-glucose 2 cotransporter inhibitors (SGLT2i) or endothelin receptor antagonists (ERA) have shown cardiorenal protective effects. The present study aimed to evaluate the cardiorenal beneficial effects of the combination of SGLT2i and ERA on top of renin-angiotensin system (RAS) blockade. Type 2 diabetic mice (db/db) were treated with different combinations of an SGLT2i (empagliflozin), an ERA (atrasentan), and an angiotensin-converting enzyme inhibitor (ramipril) for 8 weeks. Vehicle-treated diabetic mice and non-diabetic mice were included as controls. Weight, blood glucose, blood pressure, and kidney and heart function were monitored during the study. Kidneys and heart were collected for histological examination and to study the intrarenal RAS. Treatment with empagliflozin alone or combined significantly decreased blood glucose compared to vehicle-treated db/db. The dual and triple therapies achieved significantly greater reductions in diastolic blood pressure than ramipril alone. Compared to vehicle-treated db/db, empagliflozin combined with ramipril or in triple therapy significantly prevented GFR increase, but only the triple combination exerted greater protection against podocyte loss. In the heart, empagliflozin alone or combined reduced cardiac isovolumetric relaxation time (IVRT) and left atrium (LA) diameter as compared to vehicle-treated db/db. However, only the triple therapy was able to reduce cardiomyocyte area. Importantly, the add-on triple therapy further enhanced the intrarenal ACE2/Ang(1-7)/Mas protective arm of the RAS. These data suggest that triple therapy with empagliflozin, atrasentan and ramipril show synergistic cardiorenal protective effects in a type 2 diabetic mouse model.

Echocardiographic probability of pulmonary hypertension according to the old and the new definition: a validation study

Background

According to current guidelines, the diagnosis of pulmonary hypertension (PH) relies on echocardiographic probability followed by right heart catheterization. How echocardiography predicts PH recently re-defined by a mean pulmonary artery pressure (mPAP) >20 mmHg instead of ≥25 mmHg and pulmonary vascular disease defined by a pulmonary vascular resistance (PVR) >3 or >2 Wood units has not been established.

Methods

A total of 278 patients referred for PH underwent a comprehensive echocardiography followed by a right heart catheterization. Fifteen patients (5.4%) were excluded because of insufficient quality echocardiography.

Results

With PH defined by a mPAP >20 mmHg, 23 patients had no PH, 146 had pre-capillary and 94 post-capillary PH. At univariate analysis, maximum velocity of tricuspid regurgitation (TRV) ≥2.9 and ≤3.4 m/s, left ventricle (LV) eccentricity index >1.1, right ventricle (RV) outflow tract (OT) notching or acceleration time <105 ms, RV-LV basal diameter >1 and PA diameter predicted PH, whereas inferior vena cava diameter and right atrial area did not. At multivariable analysis, only TRV ≥2.9 m/s independently predicted PH. Additional independent prediction of PVR >3 Wood units was offered by LV eccentricity index >1.1 and RVOT acceleration time <105 ms and/or notching, but with no improvement of optimal combination of specificity and sensibility or positive prediction. The areas under the ROC curves for different cut-off values of TRV for the prediction of mPAP >20 mmHg, mPAP ≥25 mmHg, mPAP >20 mmHg + PVR >2 Wood units and mPAP ≥25 mmHg + PVR >3 Wood units are illustrated in Figure 1A–D.

Conclusions

Echocardiography as recommended in current guidelines can be used to assess the probability of re-defined PH in a referral center. However, the added value of indirect signs is modest and sufficient quality echocardiographic signals may not be recovered in some patients.

Funding Acknowledgement

Type of funding sources: None.

Urinary angiotensin-converting enzyme 2 and metabolomics in COVID-19-mediated kidney injury

Background

Angiotensin-converting enzyme 2 (ACE2), the receptor for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is highly expressed in the kidneys. Beyond serving as a crucial endogenous regulator of the renin-angiotensin system, ACE2 also possess a unique function to facilitate amino acid absorption. Our observational study sought to explore the relationship between urine ACE2 (uACE2) and renal outcomes in coronavirus disease 2019 (COVID-19).

Methods

In a cohort of 104 patients with COVID-19 without acute kidney injury (AKI), 43 patients with COVID-19-mediated AKI and 36 non-COVID-19 controls, we measured uACE2, urine tumour necrosis factor receptors I and II (uTNF-RI and uTNF-RII) and neutrophil gelatinase-associated lipocalin (uNGAL). We also assessed ACE2 staining in autopsy kidney samples and generated a propensity score-matched subgroup of patients to perform a targeted urine metabolomic study to describe the characteristic signature of COVID-19.

Results

uACE2 is increased in patients with COVID-19 and further increased in those that developed AKI. After adjusting uACE2 levels for age, sex and previous comorbidities, increased uACE2 was independently associated with a >3-fold higher risk of developing AKI [odds ratio 3.05 (95% confidence interval 1.23‒7.58), P = .017]. Increased uACE2 corresponded to a tubular loss of ACE2 in kidney sections and strongly correlated with uTNF-RI and uTNF-RII. Urine quantitative metabolome analysis revealed an increased excretion of essential amino acids in patients with COVID-19, including leucine, isoleucine, tryptophan and phenylalanine. Additionally, a strong correlation was observed between urine amino acids and uACE2.

Conclusions

Elevated uACE2 is related to AKI in patients with COVID-19. The loss of tubular ACE2 during SARS-CoV-2 infection demonstrates a potential link between aminoaciduria and proximal tubular injury.

P-080 Intrauterine insemination (IUI) success rates in patients with suboptimal total processed motile sperm count (TPMSC) using a second consecutive semen sample

Study question

Is it effective to request a second consecutive semen sample in patients with less than 1 million TPMSC in a first semen sample for IUI?

Summary answer

In men with TPMSC under one million, the issuing of a second consecutive sample reached pregnancy rates similar to those published for IUI.

What is known already

IUI offers a comparable cumulative live birth rate in 3-4 cycles compared to IVF and can be preferred as a cost-effective first-line treatment in mild male factor or unexplained infertility. The quality of the processed semen sample is an important factor for the IUI success.

The WHO recommends an abstinence period to ensure best quality of semen samples. However, it has been observed that when men with moderate male factor who are unable to meet the minimum requirements for IUI are asked to produce a second sample better counts are obtained; questioning the time correlation between abstinence and semen quality.

Study design, size, duration

This was a retrospective study conducted in the reproductive medicine unit of a private hospital in Chile between July 2015 and March 2021. All patients who underwent IUI in the study period that had an TPMSC less than 1 million in the eyaculate and to whom a second consecutive sample was requested were included.

Participants/materials, setting, methods

118 patients who underwent 140 IUI cycles were included in the study. All the patients with an PMSC under 1 million at the time of the IUI were requested a second consecutive semen sample within an hour or two from the previous eyaculate. The second samples were processed and used for insemination. The primary outcome was pregnancy rate. The secondary outcomes were semen quality (TPMSC of first and second semen samples).

Main results and the role of chance

Between 2015 and 2021 there were 140 IUI cycles in which a second consecutive semen sample was requested, including 118 patients. Overall 17 pregnancies were achieved. The pregnancy rate per cycle was 12,14% and the pregnancy rate per patient was 14,4%. The live birth rate per patient was 10,2%.

Regarding the sperm sample analysis, the median TPMSC of the first semen sample was 261.437. The median PMSC of the second consecutive sample was 7.315.000. 126 patients had an TPMSC of 0 in the first semen sample while only 9 patients had an IMSC of 0 in the second sample. In five cases a third consecutive sample was requested of which 4 patients had their cycles canceled because they did not meet the target PMSC. One patient had an TPMSC of 1.687.000 in the third sample.

Finally, of the 118 patients who did not meet the requirements for IUI with the first sample, only 19 cycles were canceled.

Limitations, reasons for caution

The study has the limitation of being a retrospective and descriptive study with no contol group. Also the group is heterogeneous because it includes patients with different female factors for infertility.

Wider implications of the findings

In developing countries and low-income settings the IUI remains a more accessible alternative in patients with infertility. Routinely recollecting a second semen sample in men with TPMSC <1 million would reduce cycle cancellation rates due to not achieving an optimal TPMSC, reaching pregnancy rates similar to those published for IUI.

Trial registration number

Not applicable

MO628: A Clinical Score for Identifying Non-Diabetic Nephropathy in Patients with Diabetes and Kidney Disease

BACKGROUND AND AIMS

Between 50% and 60% of diabetics with renal involvement have nondiabetic nephropathy (NDN). Renal biopsy is crucial for renal diagnosis that includes diabetic nephropathy (DN), NDN or mixed form. The objective of the current study is to provide a tool in the daily clinical practice through a predictive model of NDN that is clue for the indication of renal biopsy.

METHOD

Observational, retrospective and multicenter study was undertaken of the pathological results of kidney biopsies in patients with diabetes from 2002 to 2014. A logistic regression analysis and the probability of presenting NDN was calculated using a punctuation score.

RESULTS

The cohort of 832 patients includes 621 men (74.6%), median age 61.7 ± 12.8 years, creatinine 2.8 ± 2.2 mg/dL and proteinuria 2.7 (1.2–5.4)g/24 h. Time of evolution of diabetes was 10.8 ± 8.6 years. 26.6% (n = 221) of patients presented diabetic retinopathy, 18.8% (n = 156) peripheral vasculopathy and 17.7% (n = 147) ischemic heart disease. A total of 288 patients (34.6%) presented microhematuria. A total of 39.5% (n = 329) presented DN, 49.6% (n = 413) NDN and 10.8% (n = 90) mixed forms.

In the multivariate analysis, age (OR: 1.03; 1.01–1.04; P < 0.001), absence of microhematuria (OR: 0.6; 0.4–0.86; P = 0.005), absence of diabetic retinopathy (OR: 3.97; 2.7–5.82; P < 0.001) and absence of peripheral vasculopathy (OR: 1.61, 1.03–2.52, P = 0.038) were identified as independent risk factors for NDN. A ROC curve with an area under the curve of 0.724 was obtained. A predictive model obtaining a score (see Figure 1) for each variable and finally a NDN prediction score was performed. In our new score, the number increased as increased the probability of NDN.

CONCLUSION

In our study, ∼66% of biopsied patients with diabetes presented NDN. Microhematuria, absence of diabetic retinopathy, absence of peripheral vascular disease and older age were identified as independent risk factors for NDN. We obtained a score that increased as increased the probability of NDN. This could be in a next future a useful tool for renal biopsy indication in patients with diabetes and kidney disease.

MO631: Diabetic Retinopathy and/or Diabetic Nephropathy Confers A Worse Renal Prognosis

BACKGROUND AND AIMS

Around 50%–60% lesions of non-diabetic nephropathy (NDN) have been identified in patients with diabetes and renal biopsy. NDN patients have a better renal prognosis and survival. Diabetic retinopathy (DR) is a microvascular complication of diabetes frequently associated with diabetic nephropathy (DN). The objective of the work is to study the renal prognosis and survival of patients with DN with or without DR.

METHOD

Retrospective, observational, multicenter study of the pathological results of diabetic patients with renal biopsy was undertaken. A total of 18 Spanish centers have participated.

RESULTS

Cohort of 832 patients: 621 men (74.6%), median age 61.7 ± 12.8 years, median creatinine 2.8 ± 2.2 mg/dL and proteinuria 2.7 (1.2–5.4) g/24 h. Of them, 26.6% (n = 221) presented DR, 18.8% (n = 156) peripheral vasculopathy and 17.7% (n = 147) ischemic heart disease.

On biopsy, 39.5% (n = 329) of patients had DN, 413 (49.6%) NDN and 90 (10.8%) mixed forms. We evidenced more DR in the DN group compared with the other two groups (44.1% versus 11.1% in NDN and 33.3% in mixed forms). Regarding renal prognosis, 58.9% (n = 109) of patients with DR and DN and mixed forms required RRT versus 40.7% (n = 88) of patients without DR. A total of 39.1% (n = 18) of patients with DR and NDN required renal replacement therapy (RRT) versus 23.9% (n = 79) of patients without DR. Regarding mortality, 28.6% (n = 50) of patients with DR and DN or mixed forms died during the follow-up versus 22.7% (n = 49) of patients without DR. A total of 15.2% (n = 7) of patients with DR and NDN died and 15.4% (n = 51) of patients without DR.

In survival analysis (Kaplan—Meier curves), patients with DR had worse renal prognosis (P < 0.001), patients with DN (P < 0.001) and patients with DR and/or DN and mixed forms (P = 0.02). Cox regression analysis identified as independent risk factors of RRT: age (OR 1.014;1.025–1.004, P = 0.006), creatinine (OR 1.262; 1.217–1.309; P < 0.001), proteinuria (OR 1.057; 1.03–1.085; P < 0.001), DR (OR 1.359; 1.007–1.833; P = 0.045), DR and/or DN (OR 1.59; 2.42–1.04; P = 0.033) and DN (OR1.489; 1.05–2.11; P = 0.026).

CONCLUSION

The presence of DR and/or DN confers a worse renal prognosis. The diagnosis of diabetic microangiopathy in terms of retinopathy and/or diabetic nephropathy is crucial since it confers a worse renal prognosis indicating patients at risk of progression to end-stage renal disease.

Safety of Obtaining an Extra Biobank Kidney Biopsy Core

Background and objectives: Kidney biopsy (KB) is the “gold standard” for the diagnosis of nephropathies and it is a diagnostic tool that presents a low rate of complications. Nowadays, biobank collections of renal tissue of patients with proven renal pathology are essential for research in nephrology. To provide enough tissue for the biobank collection, it is usually needed to obtain an extra kidney core at the time of kidney biopsy. The objective of our study is to evaluate the complications after KB and to analyze whether obtaining an extra core increases the risk of complications. Material and methods: Prospective observational study of KBs performed at Vall d’Hebron Hospital between 2019 and 2020. All patients who accepted to participate to our research biobank of native kidney biopsies were included to the study. Clinical and laboratory data were reviewed and we studied risk factors associated with complications. Results: A total of 221 patients were included, mean age 56.6 (±16.8) years, 130 (58.8%) were men, creatinine was 2.24 (±1.94) mg/dL, proteinuria 1.56 (0.506–3.590) g/24 h, hemoglobin 12.03 (±2.3) g/dL, INR 0.99 (±0.1), and prothrombin time (PT) 11.86 (±1.2) s. A total of 38 patients (17.2%) presented complications associated with the procedure: 13.1% were minor complications, 11.3% (n = 25) required blood transfusion, 1.4% (n = 3) had severe hematomas, 2.3% (n = 5) required embolization, and 0.5% (n = 1) presented arterio-venous fistula. An increased risk for complication was independently associated with obtaining a single kidney core (vs. 2 and 3 cores) (p = 0.021). Conclusions: KB is an invasive and safe procedure with a low percentage of complications. Obtaining an extra kidney core for research does not increase the risk of complications during the intervention, which remains low in concordance with previously published reports.

OUP accepted manuscript

Novel coronavirus disease infection (coronavirus disease 2019, COVID-19) was declared a global pandemic in March 2020 and since then has become a major public health problem. The prevalence of COVID-19 infection and acute kidney injury (AKI) is variable depending on several factors such as race/ethnicity and severity of illness. The pathophysiology of renal involvement in COVID-19 infection is not entirely clear, but it could be in part explained by the viral tropism in the kidney parenchyma. AKI in COVID-19 infection can be either by direct invasion of the virus or as a consequence of immunologic response. Diverse studies have focused on the effect of COVID-19 on glomerulonephritis (GN) patients or the ‘novo’ GN; however, the effect of COVID-19 in acute tubulointerstitial nephritis (ATIN) has been scarcely studied. In this article, we present five cases with different spectrums of COVID-19 infection and ATIN that may suggest that recent diagnosis of ATIN is accompanied by a worse clinical prognosis in comparison with long-term diagnosed ATIN.

Evaluation of SARS-CoV-2 entry, inflammation and new therapeutics in human lung tissue cells

The development of physiological models that reproduce SARS-CoV-2 infection in primary human cells will be instrumental to identify host-pathogen interactions and potential therapeutics. Here, using cell suspensions directly from primary human lung tissues (HLT), we have developed a rapid platform for the identification of viral targets and the expression of viral entry factors, as well as for the screening of viral entry inhibitors and anti-inflammatory compounds. The direct use of HLT cells, without long-term cell culture and in vitro differentiation approaches, preserves main immune and structural cell populations, including the most susceptible cell targets for SARS-CoV-2; alveolar type II (AT-II) cells, while maintaining the expression of proteins involved in viral infection, such as ACE2, TMPRSS2, CD147 and AXL. Further, antiviral testing of 39 drug candidates reveals a highly reproducible method, suitable for different SARS-CoV-2 variants, and provides the identification of new compounds missed by conventional systems, such as VeroE6. Using this method, we also show that interferons do not modulate ACE2 expression, and that stimulation of local inflammatory responses can be modulated by different compounds with antiviral activity. Overall, we present a relevant and rapid method for the study of SARS-CoV-2.

The early stages of laboratory identification of therapeutics against pathogens is usually based on the use of immortalized cell lines, as exemplified by many studies screening antivirals against SARS-CoV-2. Cell lines are manipulated for their continuous growth which offers several advantages, however they do not fully reproduce the behavior of primary cells nor the complexity of heterogeneous populations. In this study, we overcome this limitation by using surgical resections to establish human lung tissue (HLT) cell cultures ready for drug evaluation. First, we show that HLT preserves lung cell composition, including the main SARS-CoV-2 cellular target, namely alveolar type-2 cells, as well as the proteins required for viral entry into the cells: ACE2, CD147, TMPRSS2 and AXL. Moreover, using HLT cells we identified new antiviral drug candidates missed by conventional systems, and anti-inflammatory compounds that module molecules associated with SARS-CoV-2 infection. In summary, we have established a physiological model that can be used for the identification of novel anti-SARS-CoV-2 therapeutics and other respiratory pathogens.​

Apelin pathway in cardiovascular, kidney, and metabolic diseases: Therapeutic role of apelin analogs and apelin receptor agonists

The apelin/apelin receptor (ApelinR) signal transduction pathway exerts essential biological roles, particularly in the cardiovascular system. Disturbances in the apelin/ApelinR axis are linked to vascular, heart, kidney, and metabolic disorders. Therefore, the apelinergic system has surfaced as a critical therapeutic strategy for cardiovascular diseases (including pulmonary arterial hypertension), kidney disease, insulin resistance, hyponatremia, preeclampsia, and erectile dysfunction. However, apelin peptides are susceptible to rapid degradation through endogenous peptidases, limiting their use as therapeutic tools and translational potential. These proteases include angiotensin converting enzyme 2, neutral endopeptidase, and kallikrein thereby linking the apelin pathway with other peptide systems. In this context, apelin analogs with enhanced proteolytic stability and synthetic ApelinR agonists emerged as promising pharmacological alternatives. In this review, we focus on discussing the putative roles of the apelin pathway in various physiological systems from function to dysfunction, and emphasizing the therapeutic potential of newly generated metabolically stable apelin analogs and non-peptide ApelinR agonists.

The Impact of Age on Mortality in Chronic Haemodialysis Popu-Lation with COVID-19

Age and chronic kidney disease have been described as mortality risk factors for coronavirus disease 2019 (COVID-19). Currently, an important percentage of patients in haemodialysis are elderly. Herein, we investigated the impact of age on mortality among haemodialysis patients with COVID-19. Data was obtained from the Spanish COVID-19 chronic kidney disease (CKD) Working Group Registry. From 18 March 2020 to 27 August 2020, 930 patients on haemodialysis affected by COVID-19 were included in the Registry. A total of 254 patients were under 65 years old and 676 were 65 years or older (elderly group). Mortality was 25.1% higher (95% CI: 22.2–28.0%) in the elderly as compared to the non-elderly group. Death from COVID-19 was increased 6.2-fold in haemodialysis patients as compared to the mortality in the general population in a similar time frame. In the multivariate Cox regression analysis, age (hazard ratio (HR) 1.59, 95% CI: 1.31–1.93), dyspnea at presentation (HR 1.51, 95% CI: 1.11–2.04), pneumonia (HR 1.74, 95% CI: 1.10–2.73) and admission to hospital (HR 4.00, 95% CI: 1.83–8.70) were identified as independent mortality risk factors in the elderly haemodialysis population. Treatment with glucocorticoids reduced the risk of death (HR 0.68, 95% CI: 0.48–0.96). In conclusion, mortality is dramatically increased in elderly haemodialysis patients with COVID-19. Our results suggest that this high risk population should be prioritized in terms of protection and vaccination.

[Malignant hypertension and pheochromocytoma: a case report]

Malignant arterial hypertension is defined by extremely high levels of pressure associated with organ damage. It is a cause of hypertensive emergency and is defined by the coexistence of high blood pressure and bilateral retinal haemorrhage or exudates (grade III hypertensive retinopathy), with or without papilloedema (grade IV hypertensive retinopathy) currently associated with organ damage such as renal or cardiac failure. Around 1% of malignant arterial hypertension is secondary to endocrinological causes, including the most common: pheochromocytoma, which is classically characterized by the triad: headache, sweating and palpitations. However, there is no single clinical finding that is of significant value in its diagnosis. We now present the case of a 23-year-old patient with a hypertensive emergency, an adrenal mass associated with grade IV hypertensive retinopathy.

A comparative study between real-time PCR and loop-mediated isothermal amplification to detect carbapenemase and/or ESBL genes in Enterobacteriaceae directly from bronchoalveolar lavage fluid samples

OBJECTIVES

To evaluate and compare the efficacy of real-time PCR (Xpert Carba-R) and loop-mediated isothermal amplification (Eazyplex® SuperBug CRE) for detecting carbapenemase carriage in Enterobacteriaceae directly from bronchoalveolar lavage (BAL).

METHODS

Negative BAL samples were spiked with 21 well-characterized carbapenemase-producing Enterobacteriaceae strains to a final concentration of 102-104 cfu/mL. Xpert Carba-R (Cepheid, Sunnyvale, CA, USA), which detects five targets (blaKPC, blaNDM, blaVIM, blaOXA-48 and blaIMP-1), and the Eazyplex® SuperBug CRE system (Amplex-Diagnostics GmbH, Germany), which detects seven genes (blaKPC, blaNDM, blaVIM, blaOXA-48, blaOXA-181, blaCTXM-1 and blaCTXM-9), were evaluated for the detection of these genes directly from BAL samples.

RESULTS

Xpert Carba-R showed 100% agreement with carbapenemase characterization by PCR and sequencing for all final bacteria concentrations. Eazyplex® SuperBug CRE showed 100%, 80% and 27% agreement with PCR and sequencing when testing 104, 103 and 102 cfu/mL, respectively. False negative results for Eazyplex® SuperBug CRE matched the highest cycle threshold values for Xpert Carba-R. Hands-on time for both assays was about 15 min, but Eazyplex® SuperBug CRE results were available within 30 min, whereas Xpert Carba-R took around 50 min.

CONCLUSIONS

We here describe the successful use of two commercial diagnostic tests, Xpert Carba-R and Eazyplex® SuperBug CRE, to detect bacterial carbapenem resistance genes directly in lower respiratory tract samples. Our results could be used as proof-of-concept data for validation of these tests for this indication.

COVID-19 in CKD Patients: Lessons from 553 CKD Patients with Biopsy-Proven Kidney Disease

Introduction

Chronic kidney disease (CKD) patients infected with COVID-19 are at risk of serious complications such as hospitalization and death. The prognosis and lethality of COVID-19 infection in patients with established kidney disease has not been widely studied.

Methods

Data included patients who underwent kidney biopsy at the Vall d'Hebron Hospital between January 2013 and February 2020 with COVID-19 diagnosis during the period from March 1 to May 15, 2020.

Results

Thirty-nine (7%) patients were diagnosed with COVID-19 infection. Mean age was 63 ± 15 years and 48.7% were male. Hypertension was present in 79.5%, CKD without renal replacement therapy in 76.9%, and cardiovascular disease in 64.1%. Nasopharyngeal swab was performed in 26 patients; older (p = 0.01), hypertensive (p = 0.005), and immunosuppressed (p = 0.01) patients, those using RAS-blocking drugs (p = 0.04), and those with gastrointestinal symptoms (p = 0.02) were more likely to be tested for CO­VID-19. Twenty-two patients required hospitalization and 15.4% died. In bivariate analysis, mortality was associated with older age (p = 0.03), cardiovascular disease (p = 0.05), chronic obstructive pulmonary disease (p = 0.05), and low hemoglobin levels (p = 0.006). Adjusted Cox regression showed that low hemoglobin levels at admission had 1.81 greater risk of mortality.

Conclusions

Patients with CO­VID-19 infection and kidney disease confirmed by kidney biopsy presented a mortality of 15.4%. Swab test for COVID-19 was more likely to be performed in older, hypertensive, and immunosuppressed patients, those using RAS-blocking drugs, and those with gastrointestinal symptoms. Low hemoglobin is a risk factor for mortality.

How to Assess Diabetic Kidney Disease Progression? From Albuminuria to GFR

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.

Effect of ramipril on kidney, lung and heart ACE2 in a diabetic mice model

BACKGROUND

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is responsible for the current coronavirus disease 2019 (COVID-19). The main organ affected in this infection is the lung and the virus uses the angiotensin-converting enzyme 2 (ACE2) as a receptor to enter the target cells. In this context, a controversy raised regarding the use of renin-angiotensin system (RAAS) blockers, as these drugs might increase ACE2 expression in some tissues and potentially increase the risk for SARS-CoV-2 infection. This is specially concerning in diabetic patients as diabetes is a risk factor for COVID-19.

METHODS

12-week old diabetic mice (db/db) were treated with ramipril, or vehicle control for 8 weeks. Non-diabetic db/m mice were included as controls. ACE2 expression and activity were studied in lung, kidney and heart of these animals.

RESULTS

Kidney ACE2 activity was increased in the db/db mice as compared to the db/m (143.2% ± 23% vs 100% ± 22.3%, p = 0.004), whereas ramipril had no significant effect. In the lung, no differences were found in ACE2 when comparing db/db mice to db/m and ramipril also had no significant effect. In the heart, diabetes decreased ACE2 activity (83% ± 16.8%, vs 100% ± 23.1% p = 0.02), and ramipril increased ACE2 significantly (83% ± 16.8% vs 98.2% ± 15%, p = 0.04).

CONCLUSIONS

In a mouse model of type 2 diabetes, ramipril had no significant effect on ACE2 activity in either kidneys or in the lungs. Therefore, it is unlikely that RAAS blockers or at least angiotensin-converting enzyme inhibitors increase the risk of SARS-CoV-2 infection through increasing ACE2.

MO178DOES OBTAINING AN EXTRA CORE KIDNEY BIOPSY FOR RESEARCH PURPOSES INCREASE THE RISK OF COMPLICATIONS? A SINGLE CENTER EXPERIENCE

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.

MO298A SPECIFIC TUBULAR APOA-I DISTRIBUTION IS ASSOCIATED TO FSGS RECURRENCE AFTER KIDNEY TRANSPLANTATION

Background and Aims

A major complication primary focal segmental glomerulosclerosis (FSGS) is its recurrence after kidney transplantation that happens in 30 to 40% of the patients. The diagnosis of this relapses is not always easy as the histological lesions are not highly specific and appear after the proteinuria increase. Currently, there are no accurate biomarkers to detect FSGS recurrence. Our group identified a modified form of Apolipoprotein A-I (ApoA-I), named ApoA-Ib, specifically present in urine of recurrent FSGS patients after kidney transplantation. Aberrant forms of ApoA-I have also been described in urine of native primary FSGS patients and have associated this feature to a prominent staining of ApoA-I at the apical membrane of the tubular cells. In this study we aim to analyze the ApoA-I distribution in kidney allograft biopsies of recurrent FSGS patients.

Method

We detected ApoA-I by immunohistochemistry in kidney allograft biopsies of patients with FSGS relapse after kidney transplantation (urinary ApoA-Ib positive) and in kidney allograft biopsies of patients with a disease different from FSGS in the native kidney (No-FSGS, urinary ApoA-Ib negative).

Results

In ApoA-Ib positive recurrent FSGS patients, ApoA-I was prominently localized at the brush border of the tubular cells while in the No-FSGS patients ApoA-I was found along the cytoplasm of the tubular cells (Figure 1).

Conclusion

The localization of ApoA-I at the brush border of the tubular cells is a specific feature of primary FSGS in relapse. This suggests that ApoA-I staining in kidney biopsies, coupled with ApoA-Ib measurement in urine, could be used as a diagnostic tool of primary FSGS relapse after kidney transplantation due to its highly specific tubular distribution.

MO308COULD THE PRESENCE OF ANCAS IN IGA NEPHROPATHY WITH CRESCENTS HAVE A CLINICAL IMPLICATION?

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