Multiple Pyoderma Gangrenosum Overlying AV Fistula Treated With Colchicine: A Case Report.

Rationale: Pyoderma gangrenosum (PG) is a rare neutrophilic dermatosis which gives rise to painful ulcers. Pyoderma gangrenosum can be triggered by trauma, a phenomenon called pathergy. Here, we report the first case of PG arising from pathergy due to needle insertion overlying an arteriovenous fistula (AVF). This case report seeks to inform nephrologists about PG, this yet unreported presentation, and management in the context of hemodialysis. Presenting concerns: A 69-year-old woman presented to dermatology clinic for erythemato-violaceous plaques with central ulceration at the site of needle insertion overlying her AVF. The patient was known for chronic renal insufficiency secondary to C3 glomerulonephritis, for which she received hemodialysis. After an accidental burn which lead to appearance of a painful ulcer, following each needle insertion for hemodialysis, she would develop an erythematous papule that progressed to a painful ulcer with erythematous-violaceous borders. Diagnosis: Pyoderma gangrenosum was clinically diagnosed and both clinical and paraclinical evaluation did not reveal any secondary cause of PG. Intervention: Dialysis via AVF was suspended due to the risk of triggering more PG and was temporarily pursued by central venous catheter. The patient was initially treated with prednisone and topical corticosteroids. Furthermore, owing to the high recurrence rate of PG, colchicine was initiated in prevention to avoid resorting to immunosuppressive or long-term corticotherapy. Outcomes: The patient's lesions improved on prednisone, which was then tapered over 1 month. Following prednisone taper and continuing improvement of PG on colchicine and topical corticosteroids alone, the decision was taken to recommence dialysis via AVF after performing a negative pathergy test. Topical corticosteroids were ceased due to the risk of cutaneous atrophy and were replaced by pimecrolimus ointment. The patient has continued dialysis via AVF ever since, without recurrence. Novel Finding: This is the first case reported of PG arising from pathergy due to needle insertion overlying an AVF. Colchicine may be a safe and effective therapy for long-term treatment of PG in the context of hemodialysis.

Contexte: Le Pyoderma gangrenosum (PG) est une dermatose neutrophilique rare qui provoque des ulcères douloureux. Le PG peut être déclenché par un traumatisme, un phénomène appelé pathergie. Nous rapportons ici le premier cas de PG résultant d'une pathergie au site d'insertion de l'aiguille recouvrant une fistule artérioveineuse. Ce rapport de cas vise à informer les néphrologues sur le PG, sur cette présentation non encore rapportée et sur sa prise en charge dans le contexte de l'hémodialyse. Présentation du cas: Une femme âgée de 69 ans s'étant présentée à une clinique de dermatologie pour soigner des plaques érythémateuses violacées avec ulcération centrale au site d'insertion de l'aiguille recouvrant sa fistule artérioveineuse (FAV). La patiente était connue pour une insuffisance rénale chronique secondaire à une glomérulonéphrite à C3, pour laquelle elle recevait des traitements d'hémodialyse. À la suite d'une brûlure accidentelle ayant entraîné l'apparition d'un ulcère douloureux, la patiente développait une papule érythémateuse qui évoluait vers un ulcère douloureux aux bords érythémateux violacés après chaque insertion d'aiguille pour l'hémodialyse. Diagnostic: Le Pyoderma gangrenosum a été diagnostiqué cliniquement et l'évaluation, tant clinique que paraclinique, n'a révélé aucune cause secondaire de PG. Intervention: En raison du risque accru de déclenchement de PG, la dialyse par la FAV a été suspendue et remplacée temporairement par la dialyse par cathéter veineux central. La patiente a d'abord reçu un traitement de prednisone et de corticostéroïdes topiques. En raison du taux élevé de récidive de PG, un traitement préventif à la colchicine a été initié pour éviter le recours à une corticothérapie immunosuppressive ou à long terme. Résultats: Les lésions de la patiente se sont améliorées avec le traitement à la prednisone, celui-ci a ensuite été réduit progressivement sur une période d'un mois. Après la réduction progressive de la prednisone et en raison de l'amélioration continue du PG avec le traitement par colchicine et corticostéroïdes topiques seulement, la décision a été prise de recommencer la dialyse par la FAV après un test de pathergie négatif. Un risque d'atrophie cutanée a justifié l'arrêt des corticostéroïdes topiques qui ont été remplacés par une pommade de pimecrolimus. Depuis, la patiente a poursuivi sa dialyse par FAV, sans récidive. Principales observations: Il s'agit du premier cas signalé de PG résultant d'une pathergie au site d'insertion de l'aiguille recouvrant une fistule artérioveineuse. La colchicine peut s'avérer un traitement sûr et efficace pour le traitement à long terme du PG dans le contexte de l'hémodialyse.

Clinical Characteristics and Outcomes of Drug-Induced Acute Kidney Injury Cases.

Introduction: Drug-induced acute kidney injury (DI-AKI) is a frequent adverse event. The identification of DI-AKI is challenged by competing etiologies, clinical heterogeneity among patients, and a lack of accurate diagnostic tools. Our research aims to describe the clinical characteristics and predictive variables of DI-AKI. Methods: We analyzed data from the Drug-Induced Renal Injury Consortium (DIRECT) study (NCT02159209), an international, multicenter, observational cohort study of enriched clinically adjudicated DI-AKI cases. Cases met the primary inclusion criteria if the patient was exposed to at least 1 nephrotoxic drug for a minimum of 24 hours prior to AKI onset. Cases were clinically adjudicated, and inter-rater reliability (IRR) was measured using Krippendorff's alpha. Variables associated with DI-AKI were identified using L1 regularized multivariable logistic regression. Model performance was assessed using the area under the receiver operating characteristic curve (ROC AUC). Results: A total of 314 AKI cases met the eligibility criteria for this analysis, and 271 (86%) cases were adjudicated as DI-AKI. The majority of the AKI cases were recruited from the United States (68%). The most frequent causal nephrotoxic drugs were vancomycin (48.7%), nonsteroidal antiinflammatory drugs (18.2%), and piperacillin/tazobactam (17.8%). The IRR for DI-AKI adjudication was 0.309. The multivariable model identified age, vascular capacity, hyperglycemia, infections, pyuria, serum creatinine (SCr) trends, and contrast media as significant predictors of DI-AKI with good performance (ROC AUC 0.86). Conclusion: The identification of DI-AKI is challenging even with comprehensive adjudication by experienced nephrologists. Our analysis identified key clinical characteristics and outcomes of DI-AKI compared to other AKI etiologies.

Fluid Management for Critically Ill Patients with Acute Kidney Injury Receiving Kidney Replacement Therapy: An International Survey.

BACKGROUND: In critically ill patients receiving KRT, high ultrafiltration rates and persistent fluid accumulation are associated with adverse outcomes. The purpose of this international survey was to evaluate current practices and evidence gaps related to fluid removal with KRT in critically ill patients. METHODS: This was a multinational, web-based survey distributed by seven networks comprising nephrologists and intensivists. Physicians involved in the care of critically ill patients were invited to complete a 39-question survey about fluid management practices on KRT. The survey was distributed from September 2021 to December 2021. RESULTS: There were 757 respondents from 96 countries (response rate of 65%). Most respondents practiced adult medicine (89%) and worked in an academic center (69%). The majority (91%) reported aiming for a 0.5- to 2-L negative fluid balance per day when fluid removal is indicated, although there was important variability in what respondents considered a safe maximal target. Intensivists were more likely than nephrologists to use adjunct volume status assessment methods ( i.e. , ultrasound, hemodynamic markers, and intra-abdominal pressure), while nephrologists were more likely to deploy cointerventions aimed at improving tolerance to fluid removal ( i.e. , osmotic agents and low-temperature dialysate). There was a broad consensus that rapid decongestion should be prioritized when fluid accumulation is present, but the prevention of hypotension was also reported as a competing priority. A majority (77%) agreed that performing trials that compare fluid management strategies would be ethical and clinically relevant. CONCLUSIONS: We have identified multiple areas of variability in current practice of fluid management for patients receiving KRT. Most nephrologists and intensivists agreed that several knowledge gaps related to fluid removal strategies should be investigated in future randomized controlled trials.

Spatiotemporal transitions in Pseudo-nitzschia species assemblages and domoic acid along the Alaska coast.

The toxic diatom genus Pseudo-nitzschia is distributed from equatorial to polar regions and is comprised of >57 species, some capable of producing the neurotoxin domoic acid (DA). In the Pacific Arctic Region spanning the Bering, Chukchi, and Beaufort seas, DA is recognized as an emerging human and ecosystem health threat, yet little is known about the composition and distribution of Pseudo-nitzschia species in these waters. This investigation characterized Pseudo-nitzschia assemblages in samples collected in 2018 during summer (August) and fall (October-November) surveys as part of the Distributed Biological Observatory and Arctic Observing Network, encompassing a broad geographic range (57.8° to 73.0°N, -138.9° to -169.9°W) and spanning temperature (-1.79 to 11.7°C) and salinity (22.9 to 32.9) gradients associated with distinct water masses. Species were identified using a genus-specific Automated Ribosomal Intergenic Spacer Analysis (ARISA). Seventeen amplicons were observed; seven corresponded to temperate, sub-polar, or polar Pseudo-nitzschia species based on parallel sequencing efforts (P. arctica, P. delicatissima, P. granii, P. obtusa, P. pungens, and two genotypes of P. seriata), and one represented Fragilariopsis oceanica. During summer, particulate DA (pDA; 4.0 to 130.0 ng L-1) was observed in the Bering Strait and Chukchi Sea where P. obtusa was prevalent. In fall, pDA (3.3 to 111.8 ng L-1) occurred along the Beaufort Sea shelf coincident with one P. seriata genotype, and south of the Bering Strait in association with the other P. seriata genotype. Taxa were correlated with latitude, longitude, temperature, salinity, pDA, and/or chlorophyll a, and each had a distinct distribution pattern. The observation of DA in association with different species, seasons, geographic regions, and water masses underscores the significant risk of Amnesic Shellfish Poisoning (ASP) and DA-poisoning in Alaska waters.

Factors Associated With the Use of Hypothermic Machine Perfusion in Kidney Transplant Recipients: A Multicenter Retrospective Cohort Study.

Background: Delayed graft function (DGF) is associated with an increased risk of graft loss. The use of cold hypothermic machine perfusion (HMP) has been shown to reduce the incidence of DGF in kidney transplant recipients (KTRs), especially when extended-criteria donors (ECDs) are used. HMP can also improve graft survival. However, there is a paucity of data on the determinants of HMP use in clinical practice. Objective: We aimed to determine the factors associated with the use of HMP in a cohort of donors and KTRs. Design: Multicenter retrospective cohort study. Setting: 5 transplant centers in Quebec. Patients: 159 neurologically deceased donors (NDD) and 281 KTR. Measurements: Use of HMP. Methods: We collected data on consecutive NDD admitted to a dedicated donor unit in a single university-affiliated center and their KTRs between June 2013 and December 2018 in 5 adult transplant centers across the province of Quebec, Canada. All organs were recovered in a single hospital center where a HMP device was available for every organ recovered and the decision to use HMP was left at the discretion of the procurement surgeon. Generalized estimating equations were used to predict the use of HMP. Results: The cohort included 159 NDDs and their 281 KTRs. Thirty-three percent of donors were ECDs, and 59% of KTRs received organs placed on HMP. The median cold ischemia time (CIT) was 12.5 (IQR 7.9-16.3) hours. In univariate analysis, none of the donors' characteristics were associated with the use of HMP. ECD represented 33% of KTR on HMP vs 35% of those not placed on HMP (P = .77). In univariate analysis, the use of HMP was associated with KTR race (non-Caucasian), longer CIT, use of basiliximab/alemtuzumab, year of transplant, and transplant center. The use of HMP varied largely across transplant centers, ranging from 15% to 82%. In multivariate analysis, use of HMP was associated with longer CIT (odds ratio [OR] 1.15, 95% confidence interval [CI] = 1.07-1.25), transplant center as well as transplantations performed after 2013. Limitations: One dedicated donor unit including NDD only, absence of specific data on surgeons' experience and personal or logistic reasons for using or not HMP. Conclusions: We found that use of HMP remains low and varies largely across transplant centers. The use of HMP was strongly associated with the transplant center where the surgeons practiced, suggesting that surgeon preference/training plays an important role in determining the use of HMP. Availability of HMP at the time of organ procurement might also be limited by logistic issues such as difficulty in returning the device. Further studies aimed at determining the reasons underlying the barriers precluding the use of HMP could help increasing its use and improve transplant outcomes.

Contexte: Les retards dans la reprise de fonction du greffon (RRFG) sont associés à un risque accru d'échec de la greffe. Il a été démontré que la perfusion hypothermique mécanisée (PHM) peut réduire l'incidence d'un RRFG chez les receveurs d'une greffe rénale (RGR), particulièrement dans les cas où des donneurs à critères étendus (DCÉ) sont impliqués. La PHM pourrait également améliorer la survie du greffon. Il existe cependant peu de données sur les facteurs déterminant l'utilisation de la PHM dans la pratique clinique. Objectifs: Déterminer les facteurs associés à l'utilisation de la PHM dans une cohorte de donneurs et de RGR. Type d'étude: Étude de cohorte rétrospective multicentrique. Cadre: Cinq centres de transplantation au Québec. Sujets: L'étude a inclus 159 donneurs neurologiquement décédés (DND) et 281 RGR. Mesures: L'utilisation de la PHM. Méthodologie: Nous avons recueilli les données de DND consécutifs admis entre juin 2013 et décembre 2018 dans une unité spécialisée dans le don d'organes d'un centre hospitalier universitaire, de même que les données de leurs RGR respectifs. Les sujets provenaient de cinq centres de transplantation pour adultes de la province de Québec, au Canada. Tous les organes ont été prélevés dans un centre hospitalier où un dispositif de PHM était disponible pour chaque organe prélevé, et la décision de recourir à la PHM a été laissée à la discrétion du chirurgien chargé du prélèvement. Des équations d'estimation généralisées ont été employées pour prédire l'utilisation de la PHM. Résultats: La cohorte était composée de 159 DND et de leurs 281 RGR. Les DCÉ constituaient 33 % des DND et 59 % des RGR avaient reçu un organe placé sur PHM. La durée médiane de l'ischémie froide (DmIF) était de 12,5 heures (ÉIQ: 7,9-16,3 heures). Dans l'analyse univariée, aucune des caractéristiques des donneurs n'a été associée à l'utilisation de la PHM. Des RGR de la cohorte qui avaient reçu un rein provenant d'un DCÉ, 33 % ont reçu un organe qui avait été placé sous PHM et 35 % avaient reçu un rein non perfusé à froid (p = 0,77). L'analyse univariée a également révélé une association entre l'utilisation de la PHM et l'origine ethnique du RGR (non caucasien), une DmIF prolongée, l'administration de basiliximab/alemtuzumab, l'année de la greffe et le centre de transplantation. L'utilisation de la PHM variait grandement d'un centre à un autre, allant de 15 % à 82 %. Dans l'analyse multivariée, l'utilisation de la PHM a été associée à une DmIF prolongée (rapport de cotes [RC]: 1,15; [IC95 %]: 1,07-1,25), au centre de transplantation ainsi qu'aux transplantations réalisées après 2013. Limites: Étude tenue dans une seule unité spécialisée en don d'organes et portant uniquement sur des DND. Absence de données précises sur l'expérience des chirurgiens et sur les raisons personnelles ou logistiques justifiant l'utilisation ou non de la PHM. Conclusion: Nous avons constaté que l'utilisation de la PHM demeure faible et qu'elle varie fortement d'un centre de transplantation à un autre. L'utilisation de la PHM a été fortement associée au centre de transplantation où exerçaient les chirurgiens, ce qui laisse penser que les préférences personnelles et la formation du chirurgien sont des facteurs déterminants pour son utilisation. La disponibilité de la PHM au moment du prélèvement des organes peut également être limitée par des questions logistiques telles que la difficulté de retourner l'appareil. D'autres études se penchant sur les raisons sous-jacentes aux obstacles empêchant l'utilisation de la PHM pourraient aider à en accroître l'utilisation et à améliorer les résultats de la transplantation.

Can Peer Review Be Kinder? Supportive Peer Review: A Re-Commitment to Kindness and a Call to Action.

Peer review aims to select articles for publication and to improve articles before publication. We believe that this process can be infused by kindness without losing rigor. In 2014, the founding editorial team of the Canadian Journal of Kidney Health and Disease (CJKHD) made an explicit commitment to treat authors as we would wish to be treated ourselves. This broader group of authors reaffirms this principle, for which we suggest the terminology "supportive review."

L'évaluation par les pairs vise à sélectionner les articles à publier et à en améliorer le contenu avant publication. Nous sommes d'avis que ce processus peut être fait avec bienveillance sans perdre en rigueur. En 2014, l'équipe de rédaction fondatrice du Canadian Journal of Kidney Health and Disease (CJKHD) a pris l'engagement ferme de traiter les auteurs comme ses membres souhaiteraient eux-mêmes être traités. Aujourd'hui, notre groupe élargi d'auteur(e)s réaffirme ce principe pour lequel nous proposons la terminologie « évaluation constructive ¼.

Timing of Kidney Support Therapy in Acute Kidney Injury: What Are We Waiting For?

The optimal timing of kidney support therapy in critically ill patients with acute kidney injury (AKI) without life-threatening complications related to AKI is controversial. Recent multicenter, randomized, controlled studies have questioned the need for earlier initiation of therapy, despite one study showing a benefit in survival and others with no differences in mortality based on the timing of kidney support therapy initiation. These findings reflect the uncertainties in decisions to initiate kidney support therapy, which should ideally be individualized according to the patient's comorbidities, severity of illness, trajectory of kidney function, and urine output as well as requirements for fluid balance and solute removal. A delayed approach could translate into a potentially reduced burden of dialysis dependence in addition to saving health resources. However, we must ascertain what constitutes the waiting period and the benefits and risks associated with this approach. This article reviews the concept of timing of dialysis in AKI, performs a critical assessment of the most important clinical trials in this topic, discusses ongoing research and knowledge gaps, and defines key research issues to address in the future.

Extracorporeal Treatment for Gabapentin and Pregabalin Poisoning: Systematic Review and Recommendations From the EXTRIP Workgroup.

Toxicity from gabapentin and pregabalin overdose is commonly encountered. Treatment is supportive, and the use of extracorporeal treatments (ECTRs) is controversial. The EXTRIP workgroup conducted systematic reviews of the literature and summarized findings following published methods. Thirty-three articles (30 patient reports and 3 pharmacokinetic studies) met the inclusion criteria. High gabapentinoid extracorporeal clearance (>150mL/min) and short elimination half-life (<5 hours) were reported with hemodialysis. The workgroup assessed gabapentin and pregabalin as "dialyzable" for patients with decreased kidney function (quality of the evidence grade as A and B, respectively). Limited clinical data were available (24 patients with gabapentin toxicity and 7 with pregabalin toxicity received ECTR). Severe toxicity, mortality, and sequelae were rare in cases receiving ECTR and in historical controls receiving standard care alone. No clear clinical benefit from ECTR could be identified although major knowledge gaps were acknowledged, as well as costs and harms of ECTR. The EXTRIP workgroup suggests against performing ECTR in addition to standard care rather than standard care alone (weak recommendation, very low quality of evidence) for gabapentinoid poisoning in patients with normal kidney function. If decreased kidney function and coma requiring mechanical ventilation are present, the workgroup suggests performing ECTR in addition to standard care (weak recommendation, very low quality of evidence).

Refractory Dabigatran-Induced Hemorrhage Despite Multiple Idarucizumab Administration and Renal Replacement Therapy.

PURPOSE: This case report describes a patient with dabigatran accumulation due to acute kidney injury on chronic kidney disease, requiring multiple administration of idarucizumab along with renal replacement therapy because of rebound effect causing numerous episodes of bleeding. SUMMARY: An 86-year-old man on dabigatran etexilate 110 mg twice daily for stroke prevention with atrial fibrillation was admitted to the hospital for bowel obstruction and severe acute kidney injury on chronic kidney disease. The patient had an abnormal coagulation profile and no history of bleeding. Initial laboratory values revealed a hemoglobin concentration of 10.7 g/dL, a platelet count of 115 × 103 platelets/µL, an activated partial thromboplastin time of 150.4 seconds, an international normalized ratio of 10.28, a thrombin time greater than 100 seconds and a serum creatinine of 5.54 mg/dL (490 µmol/L). An initial dose of idarucizumab was administered 1 hour prior to surgery to prevent bleeding. Significant bleeding and hemodynamic instability occurred following surgery. Three additional doses of idarucizumab, 2 sessions of intermittent hemodialysis, continuous venovenous hemofiltration and blood products were required to achieve normalization of coagulation parameters and hemodynamic stability due to rebound coagulopathy after each dose of idarucizumab. CONCLUSION: Acute kidney injury on chronic kidney disease and third-space redistribution could have led to important dabigatran accumulation and favored rebound coagulopathy. Multiple therapeutic approaches may be required in the management of complex dabigatran intoxication.

Diuretic strategies in patients with resistance to loop-diuretics in the intensive care unit: A retrospective study from the MIMIC-III database.

PURPOSE: To investigate various diuretic strategies to alleviate loop-diuretics resistance in critically ill patients. MATERIALS AND METHOD: ICU adults requiring more than 1 mg/kg/day of furosemide, from the MIMIC-III database. Four diuretic strategies were investigated: incremental dose of loop diuretics, continuous infusion, combinations with a second class of diuretics and administration of intravenous albumin. A generalized estimating equation was used to investigate the associations between these strategies and endpoints. The primary outcome was the 24-h urine output and secondary endpoints included fluid balance, weight change, electrolyte and acid-base abnormalities, kidney replacement therapy initiation, and mortality. RESULTS: A total of 7645 ICU stays from 6358 patients were included. After adjustment, the use of continuous loop-diuretic infusion was associated with a higher 24-h urine output (ß: 732, 95% CI:669-795, p < 0.001), lower 24-h fluid balance (p < 0.001) and greater weight loss at 48-h (p < 0.001). Thiazide- and carbonic anhydrase inhibitor combinations were both associated with higher urine output (p < 0.001) and weight loss at 48-h (p < 0.01), while intravenous albumin was associated with fluid gain (p < 0.001). Risks of electrolyte and metabolic disturbances varied across diuretic strategies. CONCLUSIONS: Continuous loop-diuretic infusion and thiazide- or acetazolamide-loop diuretic combinations increased urine output significantly, leading to a negative fluid balance and weight loss.

Extracorporeal treatment for poisoning to beta-adrenergic antagonists: systematic review and recommendations from the EXTRIP workgroup.

BACKGROUND: ß-adrenergic antagonists (BAAs) are used to treat cardiovascular disease such as ischemic heart disease, congestive heart failure, dysrhythmias, and hypertension. Poisoning from BAAs can lead to severe morbidity and mortality. We aimed to determine the utility of extracorporeal treatments (ECTRs) in BAAs poisoning. METHODS: We conducted systematic reviews of the literature, screened studies, extracted data, and summarized findings following published EXTRIP methods. RESULTS: A total of 76 studies (4 in vitro and 2 animal experiments, 1 pharmacokinetic simulation study, 37 pharmacokinetic studies on patients with end-stage kidney disease, and 32 case reports or case series) met inclusion criteria. Toxicokinetic or pharmacokinetic data were available on 334 patients (including 73 for atenolol, 54 for propranolol, and 17 for sotalol). For intermittent hemodialysis, atenolol, nadolol, practolol, and sotalol were assessed as dialyzable; acebutolol, bisoprolol, and metipranolol were assessed as moderately dialyzable; metoprolol and talinolol were considered slightly dialyzable; and betaxolol, carvedilol, labetalol, mepindolol, propranolol, and timolol were considered not dialyzable. Data were available for clinical analysis on 37 BAA poisoned patients (including 9 patients for atenolol, 9 for propranolol, and 9 for sotalol), and no reliable comparison between the ECTR cohort and historical controls treated with standard care alone could be performed. The EXTRIP workgroup recommends against using ECTR for patients severely poisoned with propranolol (strong recommendation, very low quality evidence). The workgroup offered no recommendation for ECTR in patients severely poisoned with atenolol or sotalol because of apparent balance of risks and benefits, except for impaired kidney function in which ECTR is suggested (weak recommendation, very low quality of evidence). Indications for ECTR in patients with impaired kidney function include refractory bradycardia and hypotension for atenolol or sotalol poisoning, and recurrent torsade de pointes for sotalol. Although other BAAs were considered dialyzable, clinical data were too limited to develop recommendations. CONCLUSIONS: BAAs have different properties affecting their removal by ECTR. The EXTRIP workgroup assessed propranolol as non-dialyzable. Atenolol and sotalol were assessed as dialyzable in patients with kidney impairment, and the workgroup suggests ECTR in patients severely poisoned with these drugs when aforementioned indications are present.

High-resolution Spatiotemporal Dynamics of Harmful Algae in the Indian River Lagoon (Florida)-A Case Study of Aureoumbra lagunensis, Pyrodinium bahamense, and Pseudo-nitzschia.

The Indian River Lagoon (IRL), located on the east coast of Florida, is a complex estuarine ecosystem that is negatively affected by recurring harmful algal blooms (HABs) from distinct taxonomic/functional groups. Enhanced monitoring was established to facilitate rapid quantification of three recurrent bloom taxa, Aureoumbra lagunensis, Pyrodinium bahamense, and Pseudo-nitzschia spp., and included corroborating techniques to improve the identification of small-celled nanoplankton (<10 µm in diameter). Identification and enumeration of these target taxa were conducted during 2015-2020 using a combination of light microscopy and species-specific approaches, specifically immunofluorescence flow cytometry as well as a newly developed qPCR assay for A. lagunensis presented here for the first time. An annual bloom index (ABI) was established for each taxon based on occurrence and abundance data. Blooms of A. lagunensis (>2×108 cells L-1) were observed in all six years sampled and across multiple seasons. In contrast, abundance of P. bahamense, largely driven by the annual temperature cycle that moderates life cycle transitions and growth, displayed a strong seasonal pattern with blooms (105-107 cells L-1) generally developing in early summer and subsiding in autumn. However, P. bahamense bloom development was delayed and abundance was significantly lower in years and locations with sustained A. lagunensis blooms. Pseudo-nitzschia spp. were broadly distributed with sporadic bloom concentrations (reaching 107 cells L-1), but with minimal concentrations of the toxin domoic acid detected (<0.02 µg L-1). In summer 2020, multiple monitoring tools characterized a novel nano-cyanobacterium bloom (reaching 109 cells L-1) that coincided with a decline in A. lagunensis and persisted into autumn. Statistical and time-series analyses of this spatiotemporally intensive dataset highlight prominent patterns in variability for some taxa, but also identifies challenges of characterizing mechanisms underlying more episodic yet persistent events. Nevertheless, the intersect of temperature and salinity as environmental proxies proved to be informative in delineating niche partitioning, not only in the case of taxa with long-standing data sets but also for seemingly unprecedented blooms of novel nanoplanktonic taxa.

Continuous Renal Replacement Therapy with oXiris® Membrane in Severe Ebstein-Barr Virus-Mediated Hemophagocytic Lymphohistiocytosis: A Case Report.

Hemophagocytic lymphohistiocytosis (HLH), a life-threatening disease with uncontrolled immune activation and inflammatory reaction, often leads to a deadly cytokine storm. In severe Ebstein-Barr virus-triggered HLH receiving standard immunosuppression, continuous renal replacement therapy (CRRT) with oXiris® blood purification membrane resulted in a timely reduction of inflammatory markers and discontinuation of vasopressors. To our knowledge, this is the first report of successful use of the oXiris® membrane in HLH.

Estimating glomerular filtration rate in patients with acute kidney injury: a prospective multicenter study of diagnostic accuracy.

BACKGROUND: Estimating glomerular filtration rate (GFR) in acute kidney injury (AKI) is challenging, with limited data comparing estimated and gold standard methods to assess GFR. The objective of our study was to assess the performance of the kinetic estimated GFR (KeGFR) and Jelliffe equations to estimate GFR in AKI, using a radioisotopic method (technetium-diethylenetriaminepentaacetic acid) as a reference measure. METHODS: We conducted a prospective multicenter observational study in hospitalized patients with AKI. We computed the Jelliffe and KeGFR equations to estimate GFR and compared these estimations to measured GFR (mGFR) by a radioisotopic method. The performances were assessed by correlation, Bland-Altman plots and smoothed and linear regressions. We conducted stratified analyses by age and chronic kidney disease (CKD). RESULTS: The study included 119 patients with AKI, mostly from the intensive care unit (63%) and with Stage 1 AKI (71%). The eGFR obtained from the Jelliffe and KeGFR equations showed a good correlation with mGFR (r = 0.73 and 0.68, respectively). The median eGFR by the Jelliffe and KeGFR equations was less than the median mGFR, indicating that these equations underestimated the mGFR. On Bland-Altman plots, the Jelliffe and KeGFR equations displayed a considerable lack of agreement with mGFR, with limits of agreement >40 mL/min/1.73 m2. Both equations performed better in CKD and the KeGFR performed better in older patients. Results were similar across AKI stages. CONCLUSIONS: In our study, the Jelliffe and KeGFR equations had good correlations with mGFR; however, they had wide limits of agreement. Further studies are needed to optimize the prediction of mGFR with estimatation equations.

Individualized acute kidney injury after care.

PURPOSE OF REVIEW: The aim of this study was to summarize the current evidence around the impact of individualizing patient care following an episode of acute kidney injury (AKI) in the ICU. RECENT FINDINGS: Over the last years, evidence has demonstrated that the follow-up care after episodes of AKI is lacking and standardization of this process is likely needed. Although this is informed largely by large retrospective cohort studies, a few prospective observational trials have been performed. Medication reconciliation and patient/caregiver education are important tenants of follow-up care, regardless of the severity of AKI. There is evidence the initiation and/or reinstitution of renin-angiotensin-aldosterone agents may improve patient's outcomes following AKI, although they may increase the risk for adverse events, especially when reinitiated early. In addition, 3 months after an episode of AKI, serum creatinine and proteinuria evaluation may help identify patients who are likely to develop progressive chronic kidney disease over the ensuing 5 years. Lastly, there are emerging differences between those who do and do not require renal replacement therapy (RRT) for their AKI, which may require more frequent and intense follow-up in those needing RRT. SUMMARY: Although large scale evidence-based guidelines are lacking, standardization of post-ICU-AKI is needed.

Risk of incident bleeding after acute kidney injury: A retrospective cohort study.

PURPOSE: End-stage kidney disease (ESKD) causes bleeding diathesis; however, whether these findings are extrapolable to acute kidney injury (AKI) remains uncertain. We assessed whether AKI is associated with an increased risk of bleeding. METHODS: Single-center retrospective cohort study, excluding readmissions, admissions <24 h, ESKD or kidney transplants. The primary outcome was the development of incident bleeding analyzed by multivariate time-dependent Cox models. RESULTS: In 1001 patients, bleeding occurred in 48% of AKI and 57% of non-AKI patients (p = .007). To identify predictors of incident bleeding, we excluded patients who bled before ICU (n = 488). In bleeding-free patients (n = 513), we observed a trend toward higher risks of bleeding in AKI (22% vs. 16%, p = .06), and a higher risk of bleeding in AKI-requiring dialysis (38% vs. 17%, p = .01). Cirrhosis, AKI-requiring dialysis, anticoagulation, and coronary artery disease were associated with bleeding (HR 3.67, 95%CI:1.33-10.25; HR 2.82, 95%CI:1.26-6.32; HR 2.34, 95%CI:1.45-3.80; and HR 1.84, 95%CI:1.06-3.20, respectively), while SOFA score and sepsis had a protective association (HR 0.92 95%CI:0.84-0.99 and HR 0.55, 95%CI:0.34-0.91, respectively). Incident bleeding was not associated with mortality. CONCLUSIONS: AKI-requiring dialysis was associated with incident bleeding, independent of anticoagulant administration. Studies are needed to better understand how AKI affects coagulation and clinical outcomes.

Quantifying systemic congestion with Point-Of-Care ultrasound: development of the venous excess ultrasound grading system.

BACKGROUND: Organ congestion is a mediator of adverse outcomes in critically ill patients. Point-Of-Care ultrasound (POCUS) is widely available and could enable clinicians to detect signs of venous congestion at the bedside. The aim of this study was to develop several grading system prototypes using POCUS and to determine their respective ability to predict acute kidney injury (AKI) after cardiac surgery. This is a post-hoc analysis of a single-center prospective study in 145 patients undergoing cardiac surgery for which repeated daily measurements of hepatic, portal, intra-renal vein Doppler and inferior vena cava (IVC) ultrasound were performed during the first 72 h after surgery. Five prototypes of venous excess ultrasound (VExUS) grading system combining multiple ultrasound markers were developed. RESULTS: The association between each score and AKI was assessed using time-dependant Cox models as well as conventional performance measures of diagnostic testing. A total of 706 ultrasound assessments were analyzed. We found that defining severe venous congestion as the presence of severe flow abnormalities in multiple Doppler patterns with a dilated IVC (≥ 2 cm) showed the strongest association with the development of subsequent AKI compared with other combinations (HR: 3.69 CI 1.65-8.24 p = 0.001). The association remained significant after adjustment for baseline risk of AKI and vasopressor/inotropic support (HR: 2.82 CI 1.21-6.55 p = 0.02). Furthermore, this severe VExUS grade offered a useful positive likelihood ratio (+LR: 6.37 CI 2.19-18.50) when detected at ICU admission, which outperformed central venous pressure measurements. CONCLUSIONS: The combination of multiple POCUS markers may identify clinically significant venous congestion.