Management and outcomes of patients on maintenance dialysis during the first and second wave of the COVID-19 pandemic in Geneva, Switzerland.

BACKGROUND: Patients on maintenance dialysis are at high risk for serious complications from COVID-19 infection, including death. We present an overview of local experience with dialysis unit management and reorganisation, local epidemiology and outcomes during the COVID-19 outbreak in Geneva, Switzerland, where SARS-CoV-2 incidence was one of the highest in Europe. METHODS: All SARS-CoV-2-positive outpatients on maintenance dialysis were transferred from their usual dialysis facility to the Geneva University Hospitals dialysis unit to avoid creation of new clusters of transmission. Within this unit, appropriate mitigation measures were enforced, as suggested by the institutional team for prevention and control of infectious diseases. RESULTS: From 25 February to 31 December 2020, 82 of 279 patients on maintenance dialysis tested positive for SARS-CoV-2 during two distinct waves, with an incidence rate of 73 cases per 100,000 person-days during the first wave and 342 cases per 100,000 during the second wave, approximately four- to six-fold higher than the general population. The majority of infections (55%) during both waves were traced to clusters. Most infections (62%) occurred in men. Sixteen patients (34%) died from COVID-19 related complications. Deceased patients were older and had a lower body mass index as compared with patients who survived the infection. CONCLUSION: SARS-CoV-2 is associated with high infection and fatality rates in the dialysis population. Strict mitigation measures seemed to be effective in controlling infection spread among patients on maintenance dialysis outside of clusters. Large scale epidemiological studies are needed to assess the efficacy of preventive measures in decreasing infection and mortality rates within the dialysis population.

[When should unilateral renal stenosis not be dilated†?] / Quand ne faut-il pas dilater une sténose unilatérale de l'artère rénale†?

Renal artery stenosis can lead to renovascular secondary hypertension. It can also induce an elevation of creatinine, but usually in the case of bilateral stenosis. In addition, it may be associated with the occurrence of heart failure and pulmonary edema. In this context, it may seem intuitive to want to dilate this artery to improve clinical outcome, but the data in current literature speak rather against this intervention. We will see that that there are some specific criteria for revascularization, but the procedure is not without risk. We present here a case of unilateral renal artery stenosis whose indication for invasive treatment was relative, exposing the patients to unnecessary risks.

Une sténose de l'artère rénale peut entraîner une hypertension artérielle secondaire de type rénovasculaire. Elle peut également induire une élévation de la créatinine, mais habituellement en cas de sténose bilatérale. De plus, elle peut être associée à la survenue d'une insuffisance cardiaque, voire d'un œdème aigu du poumon. Dans ce contexte, il peut sembler intuitif de vouloir dilater cette artère afin d'améliorer la situation clinique mais les données de la littérature parlent plutôt contre cette intervention. Nous verrons qu'il existe certains critères précis indiquant une revascularisation, mais que cette procédure n'est pas dénuée de risques. Nous présentons ici le cas d'une sténose de l'artère rénale unilatérale dont l'indication à un traitement invasif était relative, exposant le patient à des risques inutiles.

[Appropriateness of complementary exams in the initial assessment of acute kidney injury]. / Utilité des examens complémentaires dans le bilan initial d'une insuffisance rénale aiguë.

Current protocols recommend an initial assessment of acute kidney injury often extensive, not very useful in the majority of cases. A review of the literature allowed us to propose a management algorithm limiting these investigations integrating a « less is more ¼ approach. The cornerstone of this algorithm is the urinary dipstick, inexpensive and easy to perform, used as a screening test. This examination alone can, in the absence of factors suggestive of a post-renal or renal cause, guide the diagnosis and management.

Dans l'insuffisance rénale aiguë, les protocoles actuels recommandent un bilan initial souvent extensif qui s'avère inapproprié dans la majorité des cas. Une revue de la littérature nous a permis de vous proposer un algorithme de prise en charge limitant ces investigations souvent inutiles et s'inscrivant dans une approche less is more. La pierre angulaire de cet algorithme est la bandelette urinaire, peu coûteuse et facile à réaliser, utilisée comme un véritable test de dépistage. Cet examen permet à lui seul, en l'absence de facteurs évoquant une cause postrénale ou rénale, d'orienter le diagnostic et la prise en charge.

[Understanding renal functional reserve]. / Comprendre la réserve fonctionnelle rénale.

Renal function is usually estimated through the blood measurement of creatinine, which allows estimating the glomerular filtration rate (GFR). However, this value only decreases when half the nephrons are damaged, limiting the detection of early renal disease. The ingestion of an important amount of protein can increase the GFR. The renal functional reserve concept is the difference between the maximal GFR, stimulated by an important protein intake, and the baseline GFR. A diminished renal functional reserve could mean glomerular hyperfiltration and early renal disease. This value could help predicting patients more likely to present with acute renal injury and evaluating the capacity of the kidney to increase their function before a nephrectomy.

La fonction rénale est habituellement calculée à partir du dosage sanguin de la créatinine qui permet d'estimer le débit de filtration glomérulaire (DFG). Toutefois, cette valeur ne diminue que lorsque la moitié des néphrons est atteinte, la rendant peu sensible pour la détection de maladies rénales débutantes. L'ingestion de protéines permet d'augmenter le DFG par différents mécanismes. La réserve fonctionnelle rénale est la différence entre le DFG maximal, stimulé par une prise importante de protéines, et le DFG de base. Une diminution de cette réserve peut être un marqueur d'hyperfiltration glomérulaire et ainsi de maladie rénale débutante. Cette valeur peut être intéressante pour identifier les patients à risque de développer une insuffisance rénale aiguë ou évaluer le risque d'insuffisance rénale avant une néphrectomie.

[Primary glomerulonephritis in focus]. / Les glomérulonéphrites primitives en bref.

The glomerulonephritis (GN) are responsible for a significant amount of end stage renal disease. They may be secondary to another disease or idiopathic. When a secondary etiology has been excluded, it is called primary glomerulonephritis (PGN). Glomerular damage may have different presentations and there are many way to classify them. It is thus difficult for the non-specialist to understand the terminology used. This article is a summary of the most frequently encountered PGN such as: IgA nephropathy, membranous GN, idiopathic nephrotic syndrome, extracapillary and membranoproliferative GN. A brief description is given for each one of the PGN including epidemiology, semiology, histology and a pathophysiology explanation.

Use of high-volume haemodiafiltration in patients with refractory septic shock and acute kidney injury.

BACKGROUND: High-volume haemofiltration (HVHF) has been used successfully in animal models with sepsis, and preliminary data have shown that this technique may improve the haemodynamics in patients with refractory septic shock. We used high-volume continuous venovenous haemodiafiltration (CVVHDF) in patients with acute kidney injury (AKI) and refractory septic shock to evaluate their outcome when compared with their prognosis predicted by scores of severity. METHODS: This is a cohort study in a Medical and Surgical Intensive Care Unit. Fifty-five patients with refractory septic shock and AKI were included in the study. RESULTS: High-volume CVVHDF was started in patients with AKI and septic shock requiring norepinephrine dose >0.2 µg/kg/min. AKI was classified according to the RIFLE criteria. Treatment was implemented within the first 24 h of refractory septic shock with a dialysis dose of 70 mL/kg/h until reversal of shock or death. Fifty-five patients were treated with high-volume CVVHDF with an observed mortality of 63%, similar to the mortality predicted by the APACHE II and SAPS II scores. CONCLUSION: Survival rate in our patients with AKI and refractory septic shock treated with high-volume CVVHDF was identical to survival predicted by the severity scores. Treatment with high-volume haemodiafiltraton is applicable to severely ill patients with septic shock but does not confer any clear advantage in terms of survival. This therapy should not be implemented on a routine basis in patients with AKI and refractory septic shock.

Severe leptospirosis with multiple organ failure successfully treated by plasma exchange and high-volume hemofiltration.

Background. Leptospirosis is a spirochetal zoonosis with complex clinical features including renal and liver failure. Case report. We report the case of a Swiss fisherman presenting with leptospirosis. After initial improvement, refractory septic shock and severe liver and kidney failure developed. The expected mortality was estimated at 90% with clinical scores. The patient underwent plasma exchanges and high-volume hemofiltration (HVHF) with complete recovery of hepatic and kidney functions. Discussion. Plasma exchanges and HVHF may confer survival benefit on patients with severe leptospirosis, refractory septic shock, and multiple-organ failure.

[Phosphate nephropathy: how to avoid it?]. / Néphropathie au phosphate: comment l'éviter?

Colonoscopy is a commonly used procedure for colon cancer screening. The ideal bowel preparation for a good visualization of the colonic mucosa would be effective and well tolerated. Sodium phosphate (NaP) and polyethylen glycol (PEG) are the two most frequently used solutions in this indication. However, although NaP has been described as more effective and better tolerated, it can cause severe acute electrolytes disturbances and, in rare cases, lead to irreversible renal failure, called phosphate nephropathy. NaP should therefore be prescribed with caution and be formally banned for patients with risk factors.

[Drugs dosing in intensive care unit during continuous renal replacement therapy]. / Adaptation posologique des médicaments couramment utilisés en réanimation lors d'épuration extrarénale continue.

Drug dosing in the intensive care unit can be challenging. Acute kidney injury (AKI) is a common complication of sepsis and a part of multiple organ dysfunction syndrome. Continuous renal replacement therapy (CRRT) is increasingly used as dialysis therapy in this critically ill population. Available data demonstrate that sepsis, AKI and different modalities of CRRT can profoundly change drugs pharmacokinetic. The severity of these changes depends on molecules characteristics (volume of distribution, plasma protein binding, molecular weight, plasma half-life, plasma clearance), patient itself (volemia, residual renal function, tissue perfusion, hepatic dysfunction) and modality of CRRT (diffusion, convection, adsorption). There are no available recommendations to adapt drug dosing in a given critically ill patient with a given modality of CRRT. It is necessary to fully understand the different methods of CRRT and drug pharmacokinetic to prescribe the appropriate dose and to avoid under or potentially toxic overdosing. Monitoring the plasma level of drug - when available - can establish a relation between the blood concentration and its effect; thus, facilitating drug dosing.

[Statins: what is their place in the treatment of chronic kidney insufficiency?]. / Statines: quelle place dans le traitement de l'insuffisance rénale chronique?

Dyslipidemia is highly prevalent in patients with chronic kidney disease (CKD), contributing to their high cardiovascular morbidity/ mortality risk and kidney damage. The lipid profile of patients with CKD commonly shows elevation of triglycerides, accumulation of atherogenic lipoproteins and decrease of HDL cholesterol. Statins are as safe and secure in CKD patients as in the general population. Used as secondary prevention in predialysis patients they seem to reduce cardiovascular mortality, but such beneficence has not been confirmed in dialysis patients. Data are still lacking in primary prevention. Ongoing studies may help to draw more precise recommendations. Meanwhile, we suggest starting lipid lowering drugs as secondary prevention in all patients at all stages of CKD.

[Analgesia and renal insufficiency]. / Analgésie et insuffisance rénale.

Chronic kidney disease (CKD) prevalence increases with population aging and makes drugs prescription more difficult. Only a few studies have reported drug dosing adjustment in CKD patients, even in the important field of pain management. We propose an algorithm based on the current literature that helps in selecting right analgesic according to the degree of renal failure. Drug dosing adjustment of the most usually used analgesics (acetaminophen, nonsteroidal anti-inflammatory drugs and opioids) is discussed.

[Antibiotics dosing strategies in chronic kidney disease]. / Dosage des antibiotiques en cas d'insuffisance rénale chronique.

Patients with chronic kidney disease (CKD) are at high-risk for adverse drug reactions and drug-drug interactions. Drug dosing in these patients often proves to be a difficult task. Renal dysfunction-induced changes in human pathophysiology may alter medication pharmacokinetic parameters like absorption, distribution, metabolism and elimination of antibiotics. In general, drug dosing is accomplished by reducing the dose or increasing the dosing interval. Both methods can be used simultaneously. Some antibiotics are to be avoided in CKD because of lack of efficacy or increased risk of toxicity. Specific recommendations are available for helping dosing of antibiotics.