Unsupervised Cluster Analysis in Patients with Cardiorenal Syndromes: Identifying Vascular Aspects.

Background/Objectives: Cardiorenal syndrome (CRS) is a disorder of the heart and kidneys, with one type of organ dysfunction affecting the other. The pathophysiology is complex, and its actual description has been questioned. We used clustering analysis to identify clinically relevant phenogroups among patients with CRS. Methods: Data for patients admitted from 1 January 2012 to 31 December 2012 were collected from the French national medico-administrative database. Patients with a diagnosis of heart failure and chronic kidney disease and at least 5 years of follow-up were included. Results: In total, 13,665 patients were included and four clusters were identified. Cluster 1 could be described as the vascular-diabetes cluster. It comprised 1930 patients (14.1%), among which 60% had diabetes, 94% had coronary artery disease (CAD), and 80% had peripheral artery disease (PAD). Cluster 2 could be described as the vascular cluster. It comprised 2487 patients (18.2%), among which 33% had diabetes, 85% had CAD, and 78% had PAD. Cluster 3 could be described as the metabolic cluster. It comprised 2163 patients (15.8%), among which 87% had diabetes, 67% dyslipidemia, and 62% obesity. Cluster 4 comprised 7085 patients (51.8%) and could be described as the low-vascular cluster. The vascular cluster was the only one associated with a higher risk of cardiovascular death (HR: 1.48 [1.32-1.66]). The metabolic cluster was associated with a higher risk of kidney replacement therapy (HR: 1.33 [1.17-1.51]). Conclusions: Our study supports a new classification of CRS based on the vascular aspect of pathophysiology differentiating microvascular or macrovascular lesions. These results could have an impact on patients' medical treatment.

Simulation-based learning in nephrology.

Simulation is a technique to replace and amplify real experiences with guided ones that evoke or replicate substantial aspects of the real world in a fully interactive fashion. In nephrology (a particularly complex specialty), simulation can be used by patients, nurses, residents, and attending physicians alike. It allows one to learn techniques outside the stressful environment of care such as central venous catheter placement, arteriovenous fistula management, learning about peritoneal dialysis, or performing a kidney biopsy. Serious games and virtual reality are emerging methods that show promise. Simulation could also be important in relational aspects of working in a team or with the patient. The development of simulation as a teaching tool in nephrology allows for maintaining high-quality training for residents, tailored to their future practice, and minimizing risks for patients. Additionally, this education helps nephrologists maintain mastery of technical procedures, making the specialty attractive to younger generations. Unfortunately, the inclusion of simulation training programmes faces occasional logistical or funding limitations that universities must overcome with the assistance and innovation of teaching nephrologists. The impact of simulation-based teaching on clinical outcomes needs to be investigated in clinical studies.

Assessment of epidemiology and outcomes of adult patients with kidney-limited thrombotic microangiopathies.

Thrombotic microangiopathies (TMA) are usually associated with hematological features (RH-TMA). The epidemiology of TMA limited to kidneys (RL-TMA) is unclear Therefore, patients with TMA and native kidney biopsies were identified during 2009-2022 in 20 French hospitals and results evaluated. RL-TMA was present in 341/757 (45%) patients and associated with lower creatinine levels (median 184 vs 346 µmol/L) than RH-TMA. RL-TMA resulted from virtually all identified causes, more frequently from anti-VEGF treatment and hematological malignancies but less frequently from shigatoxin-associated hemolytic uremic syndrome (HUS), systemic sclerosis, gemcitabine and bacterial infection, and even less frequently when three or more causes/triggers were combined (RL-TMA: 5%; RH-TMA: 12%). RL-TMA was associated with significantly lower major cardiovascular events (10% vs 20%), kidney replacement therapy (23% vs 43%) and death (12% vs 20%) than RH-TMA during follow-up (median 28 months). Atypical HUS (aHUS) was found in 326 patients (RL-TMA: 43%, RH-TMA: 44%). Among the 69 patients with proven complement-mediated aHUS, eculizumab (anti-C5 therapy) was used in 43 (62%) (RL-TMA: 35%; RH-TMA: 71%). Among the 257 other patients with aHUS, including 51% with RL-TMA, eculizumab was used in 29 but with unclear effects of this treatment. Thus, RL-TMA represents a very high proportion of patients with TMA and results from virtually all known causes of TMA and includes 25% of patients with complement-mediated aHUS. Adverse outcomes of RL-TMA are lower compared to RH-TMA but remain significant. Anti-C5 therapy was rarely used in RL-TMA, even in proven complement-mediated aHUS, and its effects remain to be assessed.

Impact of gender on baseline presentation and outcome in adult IgA vasculitis.

OBJECTIVES: Adult IgA vasculitis (IgAV) is more common in males, but the potential impact of gender remains unclear. We aimed to describe the impact of gender on presentation and outcome in adult IgAV. METHODS: We retrospectively analysed data from a multicentre retrospective cohort of 260 patients (IGAVAS). Comparisons were made according to gender status. RESULTS: Data from 259 patients (95 females and 164 males) were analysed. Compared with females, baseline presentation in males was similar for cutaneous involvement (100% vs 100%, p= 1.0), joint involvement (60% vs 63%, p= 0.7), gastrointestinal involvement (57% vs 45%, p= 0.093) and glomerulonephritis (73% vs 64%, p= 0.16). Glomerulonephritis was more severe at baseline in males than in females, with a lower median estimated glomerular filtration rate (eGFR) (90 [IQR 59-105] vs 97 ml/min/1.73m2 [76-116], p= 0.015) and increased median proteinuria (0.84 vs 0.58 g/day, p= 0.01). There were no differences in histological findings in patients who had a kidney biopsy. Methylprednisolone was more frequently used in males (40% vs22%, p= 0.015), as were immunosuppressants, especially cyclophosphamide 24% vs 6%, p= 0.0025) and azathioprine (10% vs 2%, p= 0.038). Analysis of treatment response showed that males had more frequent refractory disease (30% vs 13%, p= 0.004). Long-term outcomes (mortality and progression to chronic kidney failure) did not differ. CONCLUSION: Kidney involvement in IgAV appears to more severe in males, which is supported by more intensive treatment contrasting with a lower response rate. This study raises the question of gender as a new prognostic factor in adult IgAV.

Thrombotic microangiopathies after kidney transplantation in modern era: nosology based on chronology.

BACKGROUND: Thrombotic microangiopathies (TMAs) are rare but can be severe in kidney transplant. recipients (KTR). METHODS: We analysed the epidemiology of adjudicated TMA in consecutive KTR during the. 2009-2021 period. RESULTS: TMA was found in 77/1644 (4.7%) KTR. Early TMA (n = 24/77 (31.2%); 1.5% of all KTR) occurred during the first two weeks ((median, IQR) 3 [1-8] days). Triggers included acute antibody-mediated rejection (ABMR, n = 4) and bacterial infections (n = 6). Graft survival (GS) was 100% and recurrence rate (RR) was 8%. Unexpected TMA (n = 31/77 (40.2%); 1.5/1000 patient-years) occurred anytime during follow-up (3.0 (0.5-6.2) years). Triggers included infections (EBV/CMV: n = 10; bacterial: n = 6) and chronic active ABMR (n = 5). GS was 81% and RR was 16%. Graft-failure associated TMA (n = 22/77 (28.6%); 2.2% of graft losses) occurred after 8.8 (4.9-15.5) years). Triggers included acute (n = 4) or chronic active (n = 14) ABMR, infections (viral: n = 6; bacterial: n = 5) and cancer (n = 6). 15 patients underwent transplantectomy. RR was 27%. Atypical (n = 6) and typical (n = 2) haemolytic and uremic syndrome, and isolated CNI toxicity (n = 4) were rare. Two-third of biopsies presented TMA features. CONCLUSIONS: TMA are mostly due to ABMR and infections; causes of TMA are frequently combined. Management often is heterogenous. Our nosology based on TMA timing identifies situations with distinct incidence, causes and prognosis.

New insights into epidemiological data and impact of the COVID-19 pandemic on IgA vasculitis in children and adults: a French nationwide cohort.

IgA vasculitis (IgAV) is a small size vasculitis for which epidemiologic data are strikingly lacking, especially about the adult form. Additionally, the COVID-19 pandemic seems to have profoundly modified the incidence of this disease. Here, we aimed to establish some relevant epidemiological data in both pediatric and adult IgAV. We performed an observational study using a national database called "BNDMR" on IgAV, which gathers patients managed in the French network of experts on rare diseases. We primarily performed descriptive statistics over the 2010-2022 period. Then, we compared the North-South geographical areas, the seasonality, and the impact of COVID-19 with that of other patients reported in the same centers. We collected data from 1988 IgAV patients. The sex ratio was 1.57 for adults and 1.05 for children. The annual incidence in 2021 was 0.06 for 100,000 adults and 0.50 for 100,000 children. Compared with other diseases reported into the BNDMR, IgAV was more common in the South than in the North of France (OR 4.88 [4.17-5.74] in adults and OR 1.51 [1.35-1.68] in children). IgAV was also observed more frequently in winter and autumn. Strikingly, we observed a decrease in incidence during the COVID-19 pandemic period in children (OR 0.62 [0.47-0.81]). Our study provides both new insights and confirmations of IgAV epidemiological data: winter and autumn seasonality, more pronounced male predominance in adults, decreasing incidence of pediatric IgAV during the COVID-19 pandemic and increasing incidence in the South of France.

Characteristics and Prognosis of Patients With Hypertensive Encephalopathy: A French Nationwide Cohort Study.

BACKGROUND: Hypertensive encephalopathy (HE) constitutes a serious condition, usually observed in patients with long-lasting hypertension. Hypertension-associated HE is sometimes differentiated from the stroke-associated hypertensive emergency. Whether prognosis of hypertension-associated and stroke-associated HE is different is unclear. METHODS: Characteristics and prognosis of HE were assessed in this nationwide retrospective cohort study in all patients with an administrative code of HE compared with age-, sex- and year of inclusion-matched controls admitted to French hospitals during the 2014 to 2022 period. RESULTS: HE was identified in 7769 patients. Chronic kidney disease (19.3%), coronary artery disease (13.8%), diabetes (22.1%), and ischemic stroke (5.2%) were frequent but thrombotic microangiopathy, hemolytic-uremic syndrome, systemic sclerosis or renal infarction were <1%. HE prognosis was poor (death: 10.4%/y, heart failure: 8.6%/y, end-stage kidney disease: 9.0%/y, ischemic stroke: 3.6%/y, hemorrhagic stroke: 1.6%/y, dementia: 4.1%/y). The risk of death was increased to a similar extent in patients with HE, regardless of the presence of known hypertension or concomitant stroke (versus patients without HE). Among patients with HE, known hypertension was significantly associated with increased risks of ischemic stroke, hemorrhagic stroke, heart failure, vascular dementia, and all-cause dementia and to a lesser extent with chronic dialysis in multivariable analyses including adjustment on concomitant stroke. CONCLUSIONS: HE remains a considerable health burden and is associated with a poor prognosis. The distinction between hypertension- versus stroke-associated HE is relevant as these 2 situations convey different risks of stroke, heart failure, vascular dementia, and end-stage kidney disease.

Cardio-renal syndrome: what's new in 2023? / Syndrome cardio-rénal : quoi de neuf en 2023 ?

Cardiac and renal pathologies lead to a high morbidity and mortality rate. The cardio-renal syndrome is characterized by the coexistence of renal and cardiac dysfunction and represents a polymorphic situation that is often complex to understand. This is a common occurrence that constitutes a real public health problem. In this review article, we propose to review the current state of knowledge on this syndrome by focusing on the main physiopathological, epidemiological, clinical and therapeutic aspects.

Les pathologies cardiaques et rénales entraînent un taux de morbi-mortalité élevé. Le syndrome cardio-rénal est caractérisé par la coexistence d'une dysfonction rénale et cardiaque et représente une situation polymorphe souvent complexe à appréhender. Il s'agit d'une conjoncture fréquente constituant une réelle problématique de santé publique. Dans cet article de revue, nous proposons de revenir sur l'état des connaissances actuelles sur ce syndrome en nous concentrant sur les principaux aspects physiopathologiques, épidémiologiques, cliniques et thérapeutiques.

Relationship between accessory renal arteries and resistant hypertension: A cohort study.

BACKGROUND: Resistant hypertension (RHT) is a major health care concern affecting 20 to 30% of hypertensive patients and increasing cardiovascular risk. Recent renal denervation trials have suggested a high prevalence of accessory renal arteries (ARA) in RHT. Our objective was to compare the prevalence of ARA in RHT vs. non-resistant hypertension (NRHT). METHODS: Eighty-six patients with essential hypertension who benefited from an abdominal CT-scan or MRI during their initial workup were retrospectively recruited in 6 French ESH (European Society of Hypertension) centers. At the end of a follow-up period of at least 6 months, patients were classified between RHT or NRHT. RHT was defined as uncontrolled blood pressure despite the optimal doses of three antihypertensive agents of which one is a diuretic or similar, or controlled by ≥ 4 medications. Blinded independent central review of all radiologic renal artery charts was performed. RESULTS: Baseline characteristics were: age 50±15 years, 62% males, BP 145±22/87±13mmHg. Fifty-three (62%) patients had RHT and 25 (29%) had at least one ARA. Prevalence of ARA was comparable between RHT (25%) and NRHT patients (33%, P=0.62), but there were more ARA per patient in NRHT (2±0.9) vs. RHT (1.3±0.5, P=0.05), and renin levels were higher in ARA group (51.6±41.7 mUI/L vs. 20.4±25.4 mUI/L, P=0.001). ARA were similar in diameter or length between the 2 groups. CONCLUSIONS: In this retrospective series of 86 essential hypertension patients, we found no difference in the prevalence of ARA in RHT and NRHT. More comprehensive studies are needed to answer this question.

Type 2 diabetes and cardiorenal syndromes. A nationwide French hospital cohort study.

AIM: Type 2 diabetes mellitus (T2DM) is a risk factor for cardiac and renal complications; its effect on cardiorenal syndromes is unknown. METHODS: In a French nationwide cohort of 5,123,193 patients hospitalized in 2012 with ≥5 years of follow-up, we assessed the effect of T2DM on cardiorenal syndrome (CRS) (using cardiorenal, renocardiac, and simultaneous subtypes) incidence and outcomes using 1:1 propensity matching. RESULTS: Among 4,605,236 adults without cardiorenal syndrome, 380,581 (8.5%) with T2DM were matched to 380,581 adults without T2DM. During follow-up, CRS occurred in 104,788 patients: simultaneous n = 25,225 (24.0%); cardiorenal n = 51,745 (49.4%); renocardiac n = 27,818 (26.5%). T2DM doubled the risk of incident CRS (1.30% versus 0.65%/year; adjusted hazard ratio (HR) for any cardiorenal syndrome: 2.14 [95% confidence interval 2.10;2.19]; renocardiac: 2.43 [2.34;2.53]; cardiorenal: 2.09 [2.03;2.15]; simultaneous: 1.94 [1.86;2.03]. Among the 26,396 adults with CRS in 2012, 11,355 (43.0%) had T2DM and were younger than non-diabetic adults (77.4 ± 9.5 versus 82.3 ± 10.0); 8,314 patients with T2DM were matched to 8,314 patients without. T2DM increased risk of: end-stage kidney disease, adjusted HR 1.50 [1.39;1.62]; myocardial infarction 1.35 [1.19;1.53]; cardiovascular death 1.20 [1.13;1.27]; heart failure 1.17 [1.12;1.21]; and all-cause death 1.09 [1.06;1.13], but not ischemic stroke. CONCLUSION: Patients with T2DM represent almost half of patients with CRS and are younger than their non-diabetic counterparts. T2DM doubles the risk of CRS and increases the risk of death, cardiovascular outcome, and end-stage kidney disease but not ischemic stroke after CRS.

Towards better indications for kidney biopsy in adult IgA vasculitis: a clinical-laboratory and pathology correlation study.

BACKGROUND: Indications for kidney biopsy in adult IgA vasculitis (IgAV) remain debated and there are very few studies on this subject. The aim of this study was to establish a correlation between renal histological and clinical-laboratory data. METHODS: A retrospective multicenter study was conducted using three databases from French hospitals, gathered between 1977 and 2020. The study included 294 adult patients with IgAV who had undergone kidney biopsy assessed according to the prognostic "Pillebout classification". Different statistical models were used to test the correlations between histological and clinical-laboratory data: Cochran Armitage, ANOVA, Kruskal-Wallis and logistic regression. RESULTS: The patients were primarily men (64%), with a mean age of 52 years. The main organs and tissues involved were: dermatological 100%, digestive 48% and rheumatological 61%. All had features of kidney involvement. The median serum creatinine was 96 µmol/L serum albumin 35 g/L, and C-reactive protein 28 mg/L. Of the patients, 86% (n = 254) had hematuria and median proteinuria was 1.8 g/day. The only statistically significant correlation between the pathological stages and the clinical-laboratory data was the presence of hematuria (p = 0.03, 66% class I to 92% class IV). In multivariate analysis, only albuminemia was associated with extracapillary proliferation (p = 0.02; OR 0.94) and only age was associated with stages 3-4 (p = 0.03; OR 1.02). CONCLUSION: Our study suggests that there is no strict baseline correlation between renal pathology and clinical-laboratory data. Given the current knowledge, it seems relevant to recommend a kidney biopsy in the presence of significant and persistent proteinuria or unexplained kidney function decline.

Long-term impact of cardiorenal syndromes on major outcomes based on their chronology: a comprehensive French nationwide cohort study.

BACKGROUND: Cardiorenal syndromes (CRSs) are reputed to result in worse prognosis than isolated heart failure (HF) and chronic kidney disease (CKD). Whether it is true for all major outcomes over the long-term regardless of CRS chronology (simultaneous, cardiorenal and renocardiac CRS) is unknown. METHODS: The 5-year adjusted risk of major outcomes was assessed in this nationwide retrospective cohort study in all 385 687 with either CKD or HF (out of 5 123 193 patients who were admitted in a French hospital in 2012). RESULTS: Overall, 84.0% patients had HF and 8.9% had CKD (they had similar age, sex ratio, diabetes and hypertension prevalence), while 7.1% had CRS (cardiorenal: 44.6%, renocardiac: 14.5%, simultaneous CRS: 40.8%).The incidence of major outcomes was 57.3%, 53.0%, 79.2% for death; 18.8%, 10.9%, 27.5% for cardiovascular death; 52.6%, 34.7%, 64.3% for HF; 6.2%, 5.5%, 5.6% for myocardial infarction (MI); 6.1%, 5.8%, 5.3% for ischaemic stroke; and 23.1%, 4.8%, 16.1% for end-stage kidney disease (ESKD) for isolated CKD, isolated HF and CRS, respectively.As compared with isolated CKD or HF, the risk of death, cardiovascular death and HF was markedly increased in CRS, the worse phenotype being cardiorenal CRS, while the increased risk of MI and ischaemic stroke associated with CRS subtypes was statistically but not clinically significant. As compared with isolated CKD, the risk of ESKD was similar for cardiorenal CRS only and marginally increased for renocardiac and simultaneous CRS. We could not find a synergy between HF and CKD on major clinical outcomes in the whole population (n = 5 123 193 patients). CONCLUSIONS: The additional impact of CRS versus isolated HF or CKD on long-term kidney and cardiovascular risk is highly heterogenous, depending of the event considered and CRS chronology. No synergy between HF and CKD could be demonstrated.

Crystalline podocytopathy and tubulopathy linked to kappa light chain deposits in a context of smoldering multiple myeloma.

A 42-year-old man with smoldering immunoglobulin G kappa multiple myeloma showed a heavy proteinuria composed of free light chain, prompting performance of a kidney biopsy. Electron microscopy revealed numerous rhomboid-shaped crystals labelled by the anti-kappa in immunogold, notably in the cytoplasm of podocytes, establishing the diagnosis of crystalline podocytopathy. This case illustrates a rare form of monoclonal gammopathy of renal significance, and highlights the key role of electron microscopy and immunogold to better elucidate the location and composition of crystals.

Intricate isavuconazole therapy of a subcutaneous nodule caused by Alternaria infectoria in a heart transplant recipient.

Invasive fungal infections have appeared to be increasingly emergent in immunocompromised patients, especially in solid organ transplant (SOT) recipients. The Alternaria genus encompasses more than 80 dematiaceus species. Among them, Alternaria alternata and Alternaria infectoria are the most frequent isolated as responsible for infection in humans. To our knowledge, we report the first case of a heart transplant recipient suffering from subcutaneous nodule caused by Alternaria infectoria and who was treated with isavuconazole. Despite all the promises of this new azole drug, one should keep in mind the potential great variability of the inter-individual responses for such complex patients. We demonstrate herein how it can be challenging to manage Alternaria infection in SOT recipients. More comprehensive studies and recommendations are expected in the context of Alternaria infections.

Kidney Biopsy in Type 2 Diabetes: A Multicenter Cross-Sectional Study.

INTRODUCTION: Kidney biopsies (KBs) are performed in patients with type 2 diabetes (T2D) to diagnose non-diabetic or hypertensive kidney disease (NDHKD) potentially requiring specific management compared to diabetic and or hypertensive nephropathy (absence of NDHKD). Indications for KB are based on the presence of atypical features compared to the typical course of diabetic nephropathy. In this study, we assessed the association of different patterns of atypical features, or KB indications, with NDHKD. METHODS: Native KBs performed in patients with T2D were analyzed. Data were collected from the patients' records. KB indications were determined according to the presence of different atypical features considered sequentially: (1) presence of any feature suggesting NDHKD which is not among the following ones, (2) recent onset of nephrotic syndrome, (3) low or rapidly declining estimated glomerular filtration rate (eGFR), (4) rapid increase in proteinuria, (5) short duration of diabetes, (6) presence of hematuria, or (7) normal retinal examination. RESULTS: Among the 463 KBs analyzed, NDHKD was diagnosed in 40% of the total population and 54, 40, 24, and 7% of the KBs performed for indications 1-4 respectively. Conversely, no patient who underwent KB for indications 5-7 displayed NDHKD. Logistic regression analyses identified eGFRCKD-EPI >15 mL/min/1.73 m2, urinary protein-to-Cr ratio <0.3 g/mmol, hematuria, HbA1c <7%, and diabetes duration <5 years as predictors of NDHKD, independently from the indication group. CONCLUSION: NDHKD is frequent in T2D. Despite the association of hematuria with NDHKD, our results suggest that presence of hematuria and absence of DR are insufficient to indicate KB in the absence of concurrent atypical features. Conversely, rapid progression of proteinuria and rapid deterioration of eGFR are major signals of NDHKD.