Clinical and Prognostic Factors in Patients with IgG4-Related Kidney Disease.

BACKGROUND: IgG4-related kidney disease is a major manifestation of IgG4-related disease, a systemic fibroinflammatory disorder. However, the clinical and prognostic kidney-related factors in patients with IgG4-related kidney disease are insufficiently defined. METHODS: We conducted an observational cohort study using data from 35 sites in two European countries. Clinical, biologic, imaging, and histopathologic data; treatment modalities; and outcomes were collected from medical records. Logistic regression was performed to identify the possible factors related to an eGFR ≤30 ml/min per 1.73 m 2 at the last follow-up. Cox proportional hazards model was performed to assess the factors associated with the risk of relapse. RESULTS: We studied 101 adult patients with IgG4-related disease with a median follow-up of 24 (11-58) months. Of these, 87 (86%) patients were male, and the median age was 68 (57-76) years. Eighty-three (82%) patients had IgG4-related kidney disease confirmed by kidney biopsy, with all biopsies showing tubulointerstitial involvement and 16 showing glomerular lesions. Ninety (89%) patients were treated with corticosteroids, and 18 (18%) patients received rituximab as first-line therapy. At the last follow-up, the eGFR was below 30 ml/min per 1.73 m 2 in 32% of patients; 34 (34%) patients experienced a relapse, while 12 (13%) patients had died. By Cox survival analysis, the number of organs involved (hazard ratio [HR], 1.26; 95% confidence interval [CI], 1.01 to 1.55) and low C3 and C4 concentrations (HR, 2.31; 95% CI, 1.10 to 4.85) were independently associated with a higher risk of relapse, whereas first-line therapy with rituximab was protective (HR, 0.22; 95% CI, 0.06 to 0.78). At their last follow-up, 19 (19%) patients had an eGFR ≤30 ml/min per 1.73 m 2 . Age (odd ratio [OR], 1.11; 95% CI, 1.03 to 1.20), peak serum creatinine (OR, 2.74; 95% CI, 1.71 to 5.47), and serum IgG4 level ≥5 g/L (OR, 4.46; 95% CI, 1.23 to 19.40) were independently predictive for severe CKD. CONCLUSIONS: IgG4-related kidney disease predominantly affected middle-aged men and manifested as tubulointerstitial nephritis with potential glomerular involvement. Complement consumption and the number of organs involved were associated with a higher relapse rate, whereas first-line therapy with rituximab was associated with lower relapse rate. Patients with high serum IgG4 concentrations (≥5 g/L) had more severe kidney disease.

Protective antibody response to mRNA-1273 and BNT162b2 vaccines in patients on maintenance haemodialysis: a prospective cohort study.

Background: Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection is more frequent and severe in patients with chronic kidney disease (CKD) on maintenance haemodialysis (HD). Vaccines are now available, but the protective response rates and determinants of humoral response to the vaccine are poorly described. Methods: This prospective observational study describes the response rates of detectable and protective antibody titres 1 month after each dose of an mRNA vaccine in a cohort of 851 patients on maintenance HD. Findings: Among naïve SARS-CoV-2 patients, a vast majority produced detectable (95.2%) or protective levels of antibodies (69.6%) 1 month after the second vaccine dose. In addition, the response rate was significantly higher with the mRNA-1273 than with the BNT162b2 vaccine 1 month after the second dose (79.8 versus 59.1%, respectively; P < 0.001). The main determinants for an inadequate humoral response were older age, treatment with immunosuppressants or oral anticoagulants and low serum albumin. All the patients who encountered coronavirus disease 2019 before vaccination also reached a highly protective humoral response. Interpretation: We found an acceptable humoral response rate in patients on maintenance HD, much higher than in transplant recipients. Therefore the third dose of vaccine may be justified in those patients with an inadequate humoral response, particularly those with a history of organ transplantation or immunosuppressive treatment.

A gain-of-function variant in the Wiskott-Aldrich syndrome gene is associated with a MYH9-related disease-like syndrome.

While loss-of-function variants in the WAS gene are associated with Wiskott-Aldrich syndrome and lead to microthrombocytopenia, gain-of-function variants of WAS are associated with X-linked neutropenia (XLN) and the absence of microthrombocytopenia. Only a few XLN families have been reported so far, and their platelet phenotype was not described in detail. To date, no renal involvement was described in XLN. In the present study, we report exome sequencing of individuals from 3 generations of a family with a dominant disease combining neutropenia, macrothrombocytopenia, and renal failure. We identified a heterozygous missense gain-of-function variant in the WAS gene (c.881T>C, p.I294T) that segregates with the disease and is already known to cause XLN. There was no pathogenic variant in MYH9, TUBB1, or ACTN1. This is the first report of a WAS gain-of-function variant associated with both the hematological phenotype of XLN (neutropenia, macrothrombocytopenia) and renal disease (proteinuria, renal failure) with glomerular tip lesion hyalinosis and actin condensations in effaced podocytes foot processes.

Impact of first-wave COronaVIrus disease 2019 infection in patients on haemoDIALysis in Alsace: the observational COVIDIAL study.

BACKGROUND: There are only scarce data regarding the presentation, incidence, severity and outcomes of coronavirus disease 2019 (COVID-19) in patients undergoing long-term haemodialysis (HD). A prospective observational study was conducted in eight HD facilities in Alsace, France, to identify clinical characteristics of HD patients with COVID-19 and to assess the determinants of the risk of death. METHODS: All HD patients tested positive for COVID-19 from 5 March to 28 April 2020 were included. Collected data included patient characteristics, clinical features at diagnosis, laboratory data, treatments and outcomes. RESULTS: Among 1346 HD patients, 123 tested positive for COVID-19. Patients had a median age of 77 years (interquartile range 66-83), with a high number of comorbidities (3.2 ± 1.6 per patient). Symptoms were compatible in 63% of patients. Asthenia (77%), diarrhoea (34%) and anorexia (32%) were frequent at diagnosis. The delay between the onset of symptoms and diagnosis, death or complete recovery was 2 (0-5), 7 (4-11) and 32 (26.5-35) days, respectively. Treatment, including lopinavir/ritonavir, hydroxychloroquine and corticosteroids, was administered in 23% of patients. The median C-reactive protein (CRP) and lymphocyte count at diagnosis was 55 mg/L (IQR 25-106) and 690 Ly/µL (IQR 450-960), respectively. The case fatality rate was 24% and determinants associated with the risk of death were body temperature {hazard ratio [HR] 1.96 [95% confidence interval (CI) 1.11-3.44]; P = 0.02} and CRP at diagnosis [HR 1.01 (95% CI 1.005-1.017); P < 0.0001]. CONCLUSIONS: HD patients were found to be at high risk of developing COVID-19 and exhibited a high rate of mortality. While patients presented severe forms of the disease, they often displayed atypical symptoms, with the CRP level being highly associated with the risk of death.

[Compliance and leaflet's reading, which link and which media? Results from a French population with chronic kidney disease]. / Observance et lecture des notices, quel lien et quels médias ? Résultats d'une population avec maladie rénale chronique.

Leaflets inside drug boxes are complex and often poorly understood. Patients consulting in nephrology are mostly old and often suffer from multiple comorbidities. As so, they are often subject to various contra-indications and drug interactions. This paper aims to evaluate if patients actually read leaflets or other medical information on others medias such as Internet and whether this could, potentially, interfere with their observance. Results showed that leaflets were read by 65.1% of patients, leading to 12% of withdrawal or not taking drugs. Furthermore, compliance to medical guidance was deemed e-read by 65.1% of patients, leading to 12% of withdrawal or not taken drugs. Furthermore, this study showed no clear profile for non-compliant patients. Even the youngest patients (under 50 years old) have had a good compliance, with not more withdrawal or not taking pills. Nonetheless, youngest patients used more often to consult alternative medias and did not read much of the leaflets' information. Patients who were reading leaflets however, tended to search further information on other medias. This situation would create new challenges in health care, as it seems that data available on new medias are not systematically validated or adapted to the needs of the patients.

[Hypertensive nephrosclerosis]. / Néphroangiosclérose.

Hypertensive nephrosclerosis is the leading cause of end stage renal disease (ESRD) in France, however, in prospective clinical trials of hypertension, ESRD accounts only for a small fraction of all events (incidence rate 0.2 to 0.4% by year). Hypertensive nephrosclerosis is characterized histologically by a series of vascular injury, none of which is truly specific and that can be observed also in obesity or normal aging. Hypertensive nephrosclerosis is mildly symptomatic, but the prognosis is never benign, due to cardiovascular and renal burden. This unspecific presentation may explain why the diagnosis of hypertensive nephrosclerosis is easily carried by excess, the main differential diagnoses are atherosclerotic ischemic renal disease, poorly symptomatic primitive nephropathies or the sequelae of unnoticed malignant hypertensive nephrosclerosis. The very high prevalence of hypertensive nephrosclerosis in populations from African ancestry has suggested a genetic predisposition. MYH9/APOL1 gene variants have recently been identified and are strongly associated with hypertensive nephrosclerosis, however the pathophysiological link between these variants and renal disease is still unclear. The treatment is mainly based on blocking the renin angiotensin system, especially when proteinuria is present. The target blood pressure is less firmly established, the latest data from the AASK study, however, do suggest a benefit on progression of lower values < 135/80 or even < 130/80 mmHg, especially in patients with proteinuria.

[Nephroprotection, fact or fiction?]. / Les promesses de la néphroprotection à l'épreuve des faits.

Clinical studies of the last 15 years have shown the benefit of pharmacological interventions on the progression of chronic kidney disease, confirming the concept of nephroprotection. Pharmacological blockade of the renin angiotensin system remains the cornerstone of the nephroprotective treatment but the benefits and limitations are now better defined. The RAS blockers are all the more efficient than the proteinuria is abundant and nephroprotection is obtained in proportion to the reduction in proteinuria. Combinations of ACEI+ARA are not validated and their use should be considered only under the supervision of a specialist when optimal monotherapy has failed. The target blood pressure has been the subject of recent controversies, particularly in type 2 diabetic patients with nephropathy. The target should be individualized based on the main risk, renal or cardiovascular. Recent maneuvers have also shown a nephroprotective effect, including the correction of metabolic acidosis with sodium bicarbonate.

Significance of membrane microparticles in solid graft and cellular transplantation.

Microparticles (MPs) are submicron vesicles released from stimulated or apoptotic cells after plasma membrane remodeling. In body fluids, they constitute relevant hallmarks of cell damage. Having long been considered inert debris reflecting cellular activation or damage, MPs are now considered as cellular effectors involved in cell-cell crosstalk. This review focuses on the pathophysiologic significance of MPs in the particular setting of solid graft and cellular transplantation.

[Contrast-induced nephropathy]. / Insuffisance rénale aiguë liée aux produits de contraste iodés.

Acute kidney injury is a common complication after contrast administration in radiology or cardiology. It increases morbidity and in-hospital but also long-term mortality. The pathophysiology is complex, there is an association of direct cellular toxicity of contrast agents and medullary ischemia secondary to alterations in intra-renal hemodynamics and to an increase in metabolic activity. Many risk factors have been identified and should be checked prior to injection, the most important being pre-existing renal failure which might be identified by calculating the estimated glomerular filtration rate with predictive equations such as Cockcroft-Gault or MDRD equations. When risk factors are present and contrast administration is really necessary, the only validated measure to reduce the risk of renal failure is still volume expansion. Other pharmacological interventions have interesting results, but a confirmation on a larger scale is necessary. The volume expansion is best performed intravenously by the isotonic saline or sodium bicarbonate.