[Kidney injury in COVID-19]. / Atteintes rénales de la COVID-19.

The SARS-CoV-2 virus causes a respiratory distress syndrome, the main symptom of COVID-19 (for "COronaVIrus Disease 2019"). This infectious disease has been causing a major health and socio-economic pandemic since December 2019. The pulmonary alveolus is regarded as the main target of SARS-CoV-2. However, this coronavirus is capable of directly or indirectly affecting other organs, including the kidneys. Here, we summarize the presumed pathophysiology of COVID-19 renal disease. The incidence of acute kidney injury ranges from 0,5 to 22 % of all patients infected with SARS-CoV-2. The need for renal replacement therapy is reported in 5-9 % of patients in intensive care. Histological analysis of renal biopsies mainly shows acute tubular necrosis of varying severity, as well as the congestion of glomerular and peri-tubular capillaries. Endothelitis has been described in few cases. Evidence for a factual inflammation of the glomerulus remains controversial. The medium/long term consequences of COVID-19 nephropathy are unknown and will deserve a tight follow-up.

Le virus SARS-CoV-2 provoque un syndrome de détresse respiratoire aiguë, le symptôme principal de l'infection COVID-19 (pour «COronaVIrus Disease 2019¼). Cette maladie infectieuse provoque une pandémie de gravité sanitaire et socio-économique majeure depuis décembre 2019. La cible principale du SARS-CoV-2 serait l'alvéole pulmonaire. Néanmoins, ce coronavirus est capable d'affecter directement ou indirectement d'autres organes, y compris les reins. Nous résumons ici la physiopathologie présumée de l'atteinte rénale de la COVID-19. L'incidence de l'insuffisance rénale aiguë varie entre 0,5 à 22 % de tous les patients infectés par le SARS-CoV-2. La nécessité d'une épuration extra-rénale est rapportée chez 5-9 % des patients pris en charge aux soins intensifs. L'analyse histologique de biopsies rénales montre, principalement, une nécrose tubulaire aiguë de sévérité variable, ainsi qu'une congestion des capillaires glomérulaires et péri-tubulaires. Une endothélite a parfois été décrite. L'atteinte inflammatoire du glomérule reste débattue. Les conséquences à moyen/long termes de la néphropathie COVID-19 sont inconnues et mériteront un suivi étroit.

Diagnostic performance of [(18)F]fluorodeoxyglucose positron emission tomography-computed tomography in cyst infection in patients with autosomal dominant polycystic kidney disease.

Cyst infection is a common complication of autosomal dominant polycystic kidney disease (ADPKD). Diagnosis is challenging with standard imaging techniques. We aimed to evaluate the diagnostic performance of [(18)F]fluorodeoxyglucose positron emission tomography-computed tomography (18-FDG PET-CT) for the diagnosis of cyst infections among ADPKD patients, in comparison with computed tomography (CT) and magnetic resonance imaging (MRI). All APKD patients who underwent 18-FDG PET-CT for suspected cyst infection between 2006 and 2013 in a French teaching hospital were included. Diagnosis of cyst infection was retained a posteriori on an index of clinical suspicion. 18-FDG PET-CT findings were was considered to be positive in cases of cyst wall hypermetabolism. CT or MRI findings were were considered to be positive in cases of cyst wall thickening (and enhancement if contrast medium was injected) and infiltration of the adjacent fat. A control group of ADPKD patients with 18-FDG PET-CT performed for other reasons was included. Thirty-two 18-FDG PET-CT scans were performed in 24 ADPKD patients with suspected cyst infection. A diagnosis of cyst infection was retained in 18 of 32 cases: 14 with positive 18-FDG PET-CT findings, and four false negatives. There were no false positives and no hypermetabolism of cyst walls in nine ADPKD control patients. 18-FDG PET-CT had a sensitivity of 77%, a specificity of 100%, and a negative predictive value of 77%. 18-FDG PET-CT allowed a differential diagnosis in three patients. In contrast, CT had a sensitivity of 7% and a negative predictive value of 35% (p <0.001 vs. 18-FDG PET-CT). Only eight MRI scans were performed. The diagnostic performance of 18-FDG PET-CT is superior to that of CT in cyst infections, for comparable radiation doses and with no injection of nephrotoxic contrast medium, in ADPKD patients.

Pathophysiology and treatment of typical and atypical hemolytic uremic syndrome.

Hemolytic uremic syndrome is a rare disease, frequently responsible for renal insufficiency in children. Recent findings have led to renewed interest in this pathology. The discovery of new gene mutations in the atypical form of HUS and the experimental data suggesting the involvement of the complement pathway in the typical form, open new perspectives for treatment. This review summarizes the current state of knowledge on both typical and atypical hemolytic uremic syndrome pathophysiology and examines new perspectives for treatment.

[Thymic disease associated with nephrotic syndrome: a new case with membranous nephropathy and literature review]. / Les syndromes néphrotiques para-thymiques : revue de la littérature à propos d'une observation.

INTRODUCTION: Malignant thymoma or thymic hyperplasia is associated with various autoimmune diseases. Renal disease has rarely been reported in this condition. We report a new case with improvement of renal disease after thymectomy. CASE REPORT: A 77-year-old-women with nephritic syndrome was found to have associated thymic mass. Renal pathology showed membranous nephropathy. The thymic mass pathology showed a B2 type thymoma. After thymectomy the nephrotic syndrome improved. CONCLUSION: Glomerulopathy can be secondary to an acquired thymic disease. Membranous nephropathy but also other glomerular diseases can be observed often presenting with nephritic syndrome. Despite the rarity of this association this clinical observation underlines that a thymoma should be searched in the presence of a glomerulopathy. The glomerulopathy can be improved by the treatment of the thymoma.

Survival of patients with ANCA-associated vasculitis on chronic dialysis: data from the French REIN registry from 2002 to 2011.

BACKGROUND: Anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitides (AAV) can lead to end-stage renal disease in patients with renal involvement. OBJECTIVE: This study evaluated the survival of AAV patients on chronic dialysis in France. METHODS: Between 2002 and 2011, a total of 425 AAV patients started chronic dialysis and were registered in the Renal Epidemiology and Information Network. We analysed survival censored for renal transplantation, recovery of renal function and loss to follow-up. AAV patients were compared with 794 matched non-AAV patients on chronic dialysis. RESULTS: A total of 166 (39%) patients with microscopic polyangiitis and 259 (61%) patients with granulomatosis with polyangiitis were registered. Within a median follow-up of 23 months, 58 (14%) patients received a renal allograft and 19 (4%) recovered renal function. Median survival on dialysis was 5.35 years (95% CI, 4.4-6.3) and survival rates at 3 months, 1, 3 and 5 years were 96%, 85%, 68% and 53%, respectively. A total of 143 (41%) patients died after a median of 16 months. Causes of death were cardiovascular (29%), infections (20%), malnutrition (13%), malignancies (4%), AAV relapse (2%), miscellaneous (14%) and unknown (18%). Multivariate logistic regression identified three independent risk factors associated with AAV patients' mortality: age (HR = 1.05/year, P < 0.001), peripheral artery disease (HR = 2.62, P = 0.003) and frailty (HR = 2.43, P < 0.001). Survival of AAV patients did not differ from non-AAV controls, but infectious mortality was higher in AAV patients (20% vs. 8%, P < 0.001). CONCLUSION: Survival of AAV patients in chronic dialysis, although poor, was comparable to survival of non-AAV controls on dialysis. There was a similar burden of cardiovascular mortality, but higher infectious mortality.

Transcriptome analysis of a rat PKD model: Importance of genes involved in extracellular matrix metabolism.

Transcriptome analysis of a rat polycystic kidney disease (PKD) model: importance of genes involved in extracellular matrix metabolism. PKD is a common genetic cause of chronic renal failure, and is characterized by the accumulation of fluid-filled cysts in the kidneys and other organs. Abnormalities in the expression of selected genes thought to be involved in cystogenesis have been described, but no systematic analysis of the global transcriptomal pattern has been reported. With this aim, a rat oligomicroarray was used to identify variations in gene expression in Han:Sprague-Dawley Cy/Cy rats, an animal model presenting a severe PKD phenotype. Some upregulated genes were validated using real-time polymerase chain reaction in Cy/Cy and Cy/+ rats. Among the 350 genes identified as being upregulated, we found about 30 genes involved in extracellular matrix metabolism. These genes encoded proteins or peptides that could be implicated into two different biological processes: molecules involved in fibrosis and proteins involved in adhesion to the extracellular matrix. In heterozygotes, some genes (glypican 3, fibronectin 1) were already upregulated in early stages of the disease. We conclude that differential regulation of genes linked to extracellular matrix metabolism may be one of the first events leading to tubule enlargement and subsequent cyst formation in PKD.

Cloning and expression of the amphibian homologue of the human PKD1 gene.

PKD1 is the gene responsible for autosomal dominant polycystic kidney disease (ADPKD) type 1 in humans. The PKD1 gene product is likely to be a calcium channel regulator. In this paper, we describe the isolation and characterization of the Xenopus homologue of the human PKD1 gene. We isolated and cloned genomic fragments corresponding to the amphibian homologue of PKD1 from a BAC library, and after sequencing the clones, we designed primers for the amplification of the transcript and sequenced 10 kb of ORF. The sequence of the putative protein clearly demonstrated that this gene is the homologue of human PKD1. Analysis of the tissue expression patterns of xPKD1 demonstrated a high level of expression in the kidney. A similar analysis in developing embryos and in an in vitro nephrogenic system suggests that xPKD1 is associated with, and probably involved in, the development of the amphibian pronephros.

Ancestrally-duplicated paraHOX gene clusters in humans.

A paraHox gene cluster has been described recently in Amphioxus. We show here using bioinformatics and cytogenetics that, as the probable result of the duplication of an ancestral paraHox gene cluster, human paraHOX genes are located in four paralogous regions of the genome, on chromosomes 4, 5, 13 and X. By analogy with the four HOX gene clusters, we propose to designate the four paraHOX gene clusters as paraHOX-A to D clusters. We also propose a scenario for the evolution of HOX and paraHOX genes. Several chromosomal translocation breakpoints of hemopathies are located in the paralogous regions that contain the paraHOX genes. Two of the paraHOX genes are involved in these rearrangements.

[Tubular necrosis after non-steroidal anti-inflammatory agents and acute alcoholic intoxication]. / Nécrose tubulaire après prise d'anti-inflammatoire non stéroïdien et intoxication éthylique aiguë.

Acute nephrotoxicity due to nonsteroidal anti-inflammatory drugs is usually observed in clinical situations in which renal perfusion is compromised as in volume contraction. We report a case of a 20 year-old woman who suffered from acute tubular necrosis after concomitant ingestion of nonsteroidal anti-inflammatory drugs and binge drinking. This acute tubular necrosis is likely to have an hemodynamic origin due to nonsteroidal anti-inflammatory drugs in a patient with volume contraction secondary to binge drinking. The risk appears to be even more important since ethanol has been implicated in tubular necrosis by direct toxicity. This observation underlines the danger in associating nonsteroidal anti-inflammatory drugs and ethanol.

[Cycloid psychoses]. / Psychoses cycloïdes.

Cycloid psychoses constitute an original classification originally proposed by Leonhard and comprising clinical pictures intermediate between schizophrenic psychoses and bipolar disorders. The exact situation of these disorders in psychiatric classifications has been the subject of debate, and their existence is still questioned. Only schizo-affective psychoses have been accepted as autonomous. Treatment of cycloid psychoses most often consists of neuroleptics but also mood regulators, particularly those having anti-epileptic effects Lastly, prognosis of these disorders usually is not as poor as that of schizophrenia and is marked by a cycloid course, with symptom-free periods between episodes.

[Sweet's syndrome and aseptic abscess of the spleen]. / Syndrome de Sweet et abcès aseptiques de la rate.

Extra-cutaneous manifestations of neutrophilic dermatosis are exceptional and diverse: they consist of inflammatory infiltrates with neutrophil polymorphonuclears, without evidence of infectious agents. Localisations to the lung are the most frequently observed. A single observation of spleen involvement has been reported in a case of Sneddon-Wilkinson's disease. Herein we report the case of an aseptic splenic abscess during the course of a Sweet's syndrome.