Urinary Biomarkers for Cell Cycle Arrest TIMP-2 and IGFBP7 for Prediction of Graft Function Recovery after Kidney Transplantation

TIMP-2 and IGFBP7 have been identified and validated for the early detection of renal injury in critically ill patients, but data on recovery of allograft function after kidney transplantation (KTx) are scarce. In a prospective observational multicenter cohort study of renal transplant recipients, urinary [TIMP-2] × [IGFBP7] was evaluated daily from day 1 to 7 after KTx. Different stages of early graft function were defined: immediate graft function (IGF) (decrease ≥ 10% in serum creatinine (s-crea) within 24 h post KTx); slow graft function (SGF) (decrease in s-crea < 10% within 24 h post KTx); and delayed graft function (DGF) (any dialysis needed within the first week after KTx). A total of 186 patients were analyzed. [TIMP-2] × [IGFBP7] was significantly elevated as early as day 1 in patients with DGF compared to SGF and IGF. ROC analysis of [TIMP-2] × [IGFBP7] at day 1 post-transplant for event "Non-DGF" revealed a cut-off value of 0.9 (ng/mL)2/1000 with a sensitivity of 87% and a specificity of 71%. The positive predictive value for non-DGF was 93%. [TIMP-2] × [IGFBP7] measured at day 1 after KTx can predict early recovery of transplant function and is therefore a valuable biomarker for clinical decision making.

Binding and detoxification efficiency of albumin decline after haemodialysis

BACKGROUND

Albumin, as the most abundant plasma protein, represents a target structure for both drug and physicochemical therapeutic approaches to eliminate uraemic toxins more efficiently. Potentially, this approach could reduce mortality of haemodialysis patients. However, little is known about albumin functional properties in these patients and its alteration by haemodialysis treatment.

METHODS

The binding and detoxification efficiency of albumin were assessed by electron paramagnetic resonance spectroscopy using a spin-labelled fatty acid. Binding efficiency (BE) reflects strength and amount of bound fatty acids under certain ethanol concentration. Detoxification efficiency (DTE) reflects the molecular flexibility of the patient's albumin molecule, thus the ability to change the conformation depending on ethanol concentration. Percentage of BE and DTE are depicted in relation to healthy individuals (100%).

RESULTS

Fifty-eight patients (59% male, median age 68 years, median time on haemodialysis 32 months) were included in the study. Before haemodialysis treatment, albumin binding and detoxification efficiency were substantially below healthy individuals [median BE 52% (interquartile range, IQR, 45%-59%); median DTE 38% (IQR 32-49%)]. After haemodialysis treatment, median BE and DTE significantly decreased [BE 28% (IQR 20-41%); DTE 11% (IQR 7%-27%; P < .001)]. BE and DTE decline after haemodialysis was not dependent on age, sex or treatment modalities, but was to a certain extent on the level of non-esterified fatty acids.

CONCLUSION

Albumin binding and detoxification efficiency of fatty acids in maintenance haemodialysis patients were substantially below those in healthy individuals and even declined after dialysis treatment. These findings might be helpful when considering new therapeutic approaches in maintenance haemodialysis patients.

Antibody responses after sequential vaccination with PCV13 and PPSV23 in kidney transplant recipients

PURPOSE

Vaccination against Streptococcus pneumoniae is recommended in transplant recipients to reduce the morbidity and mortality from invasive pneumococcal disease. Previous studies indicate that transplant recipients can produce specific antibodies after vaccination with the 13-valent pneumococcal conjugate vaccine Prevenar 13 (PCV13) or the pneumococcal polysaccharide vaccine Pneumovax 23 (PPSV23). National guidelines recommend sequential vaccination with PCV13 followed by PPSV23 in kidney transplant patients. However, there are currently no data on the serological response in kidney transplant recipients, who received a sequential vaccination with PCV13 and PPSV23.

METHODS

In the current study, we sequentially vaccinated 46 kidney transplant recipients with PCV13 and PPSV23 and determined global and serotype-specific anti-pneumococcal antibody responses in the year following vaccination.

RESULTS

Serotype-specific and global anti-pneumococcal antibody concentrations were significantly higher compared to baseline. We observed that serotype-specific antibody responses varied by serotype (between 2.2- and 2.9-fold increase after 12 months). The strongest responses after 12 months were detected against the serotypes 9N (2.9-fold increase) and 14 (2.8-fold increase). Global antibody responses also varied with respect to immunoglobulin class. IgG2 revealed the highest increase (2.7-fold), IgM the lowest (1.7-fold). Sequential vaccination with both vaccines achieved higher antibody levels in comparison with a historical cohort studied at our institute, that was vaccinated with PCV13 alone. During the 12-months follow-up period, none of the patients developed pneumococcal-associated pneumonia or vaccination-related allograft rejection.

CONCLUSION

In conclusion, we strongly recommend sequential vaccination over single immunization in kidney transplant recipients.

Effect of stress hyperglycaemia on acute kidney injury in non-diabetic critically ill patients?

BACKGROUND

Stress hyperglycaemia (SH) and acute kidney injury (AKI) occur frequently in critically ill patients, and particularly non-diabetics are associated with adverse outcome. Data is scarce on the effect of SH on AKI. We assessed whether SH (i) preceded AKI, (ii) was a risk factor of subsequent AKI, and (iii) how SH and tubular injury interacted in AKI development in critically ill, non-diabetics.

METHODS

Case-control study of 82 patients each with and without SH matched by propensity score for multiple demographic characteristics. AKI was defined by KDIGO criteria, SH either as blood glucose (BG) > 140 mg/dl (BG140), > 200 mg/dl (BG200), or stress hyperglycemia rate (SHR) ≥ 1.47 (SHR1.47) as measured 2 days before AKI. Urinary cystatin C and neutrophil gelatinase-associated lipocalin (NGAL) indicated tubular injury.

RESULTS

In AKI, SH rates were frequent using all 3 definitions applied, but highest when BG140 was applied. SH by all 3 definitions was consistently associated with AKI. This was independent of established risk factors of AKI such as sepsis and shock. Increments of BG, urinary NGAL or cystatin C, and its products, were independently associated with the likelihood of subsequent AKI, demonstrating their reciprocal potentiating effects on AKI development.

CONCLUSIONS

SH is frequent in critically ill, non-diabetics with AKI. SH was identified as an independent risk factor of AKI. Higher BG combined with tubular injury may potentiate their adverse effects on AKI.

Effect of serum creatinine difference between the Jaffe and the enzymatic method on kidney disease detection and staging

Background

Serum creatinine (SCr), mainly determined by the Jaffe or an enzymatic method, is the central marker to assess kidney function. Deviations between these two methods may affect the diagnosis and staging of acute kidney injury (AKI) and chronic kidney disease (CKD).

Methods

The results of the first parallel SCr measurement (Jaffe and enzymatic method) of adult in- and outpatients in the same serum sample at the University Hospital Essen (Essen, Germany) between 2020-2022 were retrospectively evaluated. A Bland-Altman plot with 95% limits of agreement (LoAs) was used to assess the difference between the Jaffe and the enzymatic SCr (eSCr) method. We used the 2009 Chronic Kidney Disease Epidemiology Collaboration equation for determination of estimated glomerular filtration rate (eGFR) according to the Kidney Disease: Improving Global Outcomes guidelines.

Results

A total of 41 144 parallel SCr measurements were evaluated. On average, Jaffe SCr was 0.07 mg/dl higher than eSCr (LoA -0.12; 0.25 mg/dl). In 19% of all cases there was a different CKD stage when comparing eGFR between both SCr methods, of which 98% resulted in a more severe CKD stage determined with Jaffe SCr. In 1.6% of all cases Jaffe SCr was ≥0.3 mg/dl higher than eSCr.

Conclusion

The present study showed that methods of SCr measurement may affect both the diagnosis and staging of AKI and CKD. This must be taken into account when interpreting measurements of renal function in everyday clinical practice, but also when planning and comparing studies on renal diseases. One should therefore stay with one method for SCr measurement, preferably with the enzymatic method.

Single-Nucleotide Polymorphism in Genes Encoding G Protein Subunits GNB3 and GNAQ Increase the Risk of Cardiovascular Morbidity among Patients Undergoing Renal Replacement Therapy

Single-nucleotide polymorphisms in G protein subunits are linked to an increased risk of cardiovascular events among the general population. We assessed the effects of GNB3 c.825C > T, GNAQ -695/-694GC > TT, and GNAS c.393C > T polymorphisms on the risk of cardiovascular events among 454 patients undergoing renal replacement therapy. The patients were followed up for a median of 4.5 years after the initiation of dialysis. Carriers of the TT/TT genotype of GNAQ required stenting because of coronary artery stenosis (p = 0.0009) and developed cardiovascular events involving more than one organ system (p = 0.03) significantly earlier and more frequently than did the GC/TT or GC/GC genotypes. Multivariate analysis found that the TT/TT genotype of GNAQ was an independent risk factor for coronary artery stenosis requiring stent (hazard ratio, 4.5; p = 0.001), cardiovascular events (hazard ratio, 1.93; p = 0.04) and cardiovascular events affecting multiple organs (hazard ratio, 4.9; p = 0.03). In the subgroup of male patients left ventricular dilatation with abnormally increased LVEDD values occurred significantly more frequently in TT genotypes of GNB3 than in CT/CC genotypes (p = 0.007). Our findings suggest that male dialysis patients carrying the TT genotype of GNB3 are at higher risk of left ventricular dilatation and that dialysis patients carrying the TT/TT genotype of GNAQ are prone to coronary artery stenosis and severe cardiovascular events.

Endotoxin-Induced Physiological and Psychological Sickness Responses in Healthy Humans: Insights into the Post-Acute Phase

INTRODUCTION

Experimental endotoxemia is a translational model of systemic inflammation that has contributed significantly to our current understanding of sickness behavior and inflammation-associated depression. Previous studies using this model revealed a strong association between cytokine levels, endocrine changes, and psychological sickness symptoms during the acute phase of inflammation. The objective of this randomized, double-blind, placebo-controlled crossover study was to gain insight into potential post-acute physiological and psychological consequences of endotoxin administration that may either persist or newly emerge between 24 and 72 h after injection. The main focus was on associations between serum levels of C-reactive protein (CRP) and affective symptoms as well as alterations in diurnal cortisol profile, the two key features of inflammation-associated depression.

METHODS

Healthy male volunteers (N = 18) received an injection of either endotoxin (0.8 ng/kg) or placebo on two separate but otherwise identical study days, 7 days apart. Blood and saliva samples were collected during acute and post-acute phases after injection to measure blood inflammatory markers (interleukin [IL]-6, IL-1 receptor antagonist [ra], CRP) and salivary cortisol levels. In addition, participants completed a comprehensive battery of questionnaires to assess physical and psychological sickness symptoms.

RESULTS

Endotoxin treatment induced a short-time rise in plasma IL-6 and a longer increase in IL-1ra. The increase in serum CRP was delayed compared to cytokines, peaking at 24 h and gradually decreasing until 72 h after injection. The inflammatory response was accompanied by bodily and psychological sickness symptoms which occurred only in the acute phase, whereas none of the symptoms persisted or recurred in the post-acute phase. Salivary cortisol levels were significantly increased during the acute phase and exhibited pronounced circadian changes. However, no significant differences in diurnal cortisol profiles were observed between placebo and endotoxin conditions on the days after treatment.

CONCLUSION

Our findings suggest that CRP, which is elevated in patients with inflammation-associated depression, does not appear to be responsible for depressive symptomatology. Moreover, a single inflammatory episode is not sufficient to alter diurnal cortisol profiles, as observed in inflammation-associated depression. In addition, the absence of persistent lipopolysaccharide-induced psychological and physiological changes beyond the acute phase further supports the safety of endotoxin administration in humans.

Albumin redox state of maintenance haemodialysis patients is positively altered after treatment

BACKGROUND AND AIM

Maintenance haemodialysis patients have increased morbidity and mortality which is mainly driven by an elevated inflammation level due to the uraemic milieu. A major part of this increased inflammation level is the degree of oxidative stress which can be assessed by albumin redox state (ARS). Aim of this study was to evaluate how the ARS is affected by a haemodialysis treatment and different dialyzer properties.

METHODS

ARS was determined before and after haemodialysis treatment by fractionating it into reduced human mercaptalbumin (HMA), reversibly oxidized human non-mercaptalbumin 1 (HNA-1), and irreversibly oxidized human non-mercaptalbumin 2 (HNA-2) by high-performance liquid chromatography. In healthy individuals, albumin circulates in the following proportions: HMA 70-80%, HNA-1 20-30% and HNA-2 2-5%. High flux (FX 100 [Fresenius Medical Care], BG 1.8 [Toray], Xevonta Hi 18 [B. Braun], CTA-2000 [Kawasumi]) and low flux FX10 [Fresenius Medical Care] dialyzers were used.

RESULTS

58 patients (59% male, median age 68 years, median time on haemodialysis 32 month) were included in the study. Before haemodialysis treatment, HMA (median 55.9%, IQR 50.1-61.2%) was substantially lower than in healthy individuals. Accordingly, oxidized albumin fractions were above the level of healthy individuals (median HNA-1 38.5%, IQR 33.3-43.2%; median HNA-2 5.8%, IQR 5.1-6.7%). Before haemodialysis treatment HMA was significantly higher in patients usually treated with high flux membranes (p < 0.01). After haemodialysis treatment there was a significant increase of HMA and a decrease of HNA-1 and HNA-2 (p < 0.01). These effects were more pronounced in patients treated with high flux dialyzers (p < 0.01). There were no differences of ARS alteration with regard to the dialyzer´s sterilization mode or the presence of diabetes.

CONCLUSION

The study confirms that the ARS is positively altered by haemodialysis and shows for the first time that this effect depends on dialyzer properties.

Expression of Interferon Regulatory Factor 8 (IRF8) and Its Association with Infections in Dialysis Patients

Patients on dialysis have dysfunctions of innate and adaptive immune system responses. The transcriptional factor IRF8 (interferon regulatory factor 8) is primarily expressed in plasmacytoid cells (pDCs) and myeloid dendritic cells (mDCs), playing a crucial role in the maturation of dendritic cells, monocytes, and macrophages, and contributing to protection against bacterial infections. The current study analyzed the expression patterns of IRF8 and assessed its association with the risk of infections in 79 dialysis patients compared to 44 healthy controls. Different subsets of leukocytes and the intracellular expression of IRF8 were measured using flow cytometry. Compared to the healthy controls, the dialysis patients showed significantly reduced numbers of pDCs and significantly increased numbers of natural killer cells and classical and intermediate monocytes. The dialysis patients exhibited decreased numbers of IRF8-positive dendritic cells (pDC p < 0.001, mDC1 p < 0.001, mDC2 p = 0.005) and increased numbers of IRF8-positive monocytes (p < 0.001). IRF8 expression in pDC, mDC, and classical monocytes was lower in the dialysis patients than in the controls. Dialysis patients who required hospitalization due to infections within one year of follow-up displayed significantly reduced IRF8 expression levels in pDCs compared to patients without such infections (p = 0.04). Our results suggest that reduced IRF8 expression in pDCs is a potential risk factor predisposing dialysis patients to serious infections.

Impact of first-line use of caplacizumab on treatment outcomes in immune thrombotic thrombocytopenic purpura

BACKGROUND

The von Willebrand factor-directed nanobody caplacizumab has greatly changed the treatment of immune thrombotic thrombocytopenic purpura (iTTP) in recent years. Data from randomized controlled trials established efficacy and safety.

OBJECTIVES

This study aims to address open questions regarding patient selection, tailoring of therapy duration, obstacles in prescribing caplacizumab in iTTP, effect on adjunct treatment, and outcomes in the real-world setting.

METHODS

We report retrospective, observational cohorts of 113 iTTP episodes treated with caplacizumab and 119 historical control episodes treated without caplacizumab. We aggregated data from the caplacizumab phase II/III trials and real-world data from France, the United Kingdom, Germany, and Austria (846 episodes, 396 treated with caplacizumab, and 450 historical controls).

RESULTS

Caplacizumab was efficacious in iTTP, independent of the timing of therapy initiation, but curtailed the time of active iTTP only when used in the first-line therapy within 72 hours after diagnosis and until at least partial ADAMTS13-activity remission. Aggregated data from multiple study populations showed that caplacizumab use resulted in significant absolute risk reduction of 2.87% for iTTP-related mortality (number needed to treat 35) and a relative risk reduction of 59%.

CONCLUSION

Caplacizumab should be used in first line and until ADAMTS13-remission, lowers iTTP-related mortality and refractoriness, and decreases the number of daily plasma exchange and hospital stay. This trial is registered at www.

CLINICALTRIALS

gov as #NCT04985318.

[Staging of kidney disease today and tomorrow]

Since September 2022, there is a new, German-language glossary for the nomenclature of renal function and renal disease, aligned with international technical terms and KDIGO guidelines for a more precise and uniform description of the facts. Terms such as "renal disease," "renal insufficiency," or "acute renal failure" should be avoided and replaced with "disease" or "functional impairment."The KDIGO guideline recommends in patients with CKD stage G3a, in addition to the determination of serum creatinine, the additional determination of cystatin to confirm the CKD stage. A combination of serum creatinine and cystatin C to estimate GFR without taking into account the so-called race coefficient seems to be more accurate in African Americans than the previous eGFR formulas. However, there is no recommendation on this in international guidelines yet. For Caucasians, the formula does not change.Renal function impairment lasting more than 7 days but less than 3 months is called acute kidney disease (AKD). The AKD stage is the critical time window for therapeutic interventions to reduce the risk of progression in kidney disease.A future, expanded AKI definition incorporating biomarkers will allow patients to be divided into subclasses according to functional and structural limitations, thus mapping the two-dimensionality of AKI. By using artificial intelligence, large amounts of data from clinical parameters, blood and urine samples, histopathological and molecular markers (including proteomics and metabolomics data) can be used integratively for the graduation of CKD and thus contribute significantly to individualized therapy.

Effect of intraoperative haemoadsorption therapy on cardiac surgery for active infective endocarditis with confirmed Staphylococcus aureus bacteraemia

OBJECTIVES

Sepsis caused by infective endocarditis (IE), due to Staphylococcus aureus, is associated with significant morbidity and mortality. Blood purification using haemoadsorption (HA) may attenuate the inflammatory response. We investigated the effect of intraoperative HA on postoperative outcomes in S. aureus IE.

METHODS

Patients with confirmed S. aureus IE undergoing cardiac surgery were included in a dual-centre study between January 2015 and March 2022. Patients treated with intraoperative HA (HA group) were compared to patients not treated with HA (control group). The primary outcome was vasoactive-inotropic score within the first 72 h postoperatively and secondary outcomes were sepsis-related mortality (SEPSIS-3 definition) and overall mortality at 30 and 90 days.

RESULTS

No differences in baseline characteristics were observed between groups (haemoadsorption group, n = 75, control group, n = 55). Significantly decreased vasoactive-inotropic score was observed in the haemoadsorption group at all time points [6 h: 6.0 (0-17) vs 17 (3-47), P = 0.0014; 12 h: 2 (0-8.3) vs 5.9 (0-37), P = 0.0138; 24 h: 0 (0-5) vs 4.9 (0-23), P = 0.0064; 48 h: 0 (0-2.1) vs 0.1 (0-13), P = 0.0192; 72 h: 0 (0) vs 0 (0-5), P = 0.0014]. Importantly, sepsis-related mortality (8.0% vs 22.8%, P = 0.02) and 30-day (17.3% vs 32.7%, P = 0.03) and 90-day overall mortality (21.3% vs 40%, P = 0.03) were also significantly lower with haemoadsorption.

CONCLUSIONS

Intraoperative HA during cardiac surgery for S. aureus IE was associated with significantly lower postoperative vasopressor and inotropic requirements and resulted in lower sepsis-related and overall 30- and 90-day mortality. In this high-risk population, improved postoperative haemodynamic stabilization by intraoperative HA appears to improve survival and should be further tested in future randomized trials.

Incidence, severity, risk factors and outcomes of acute kidney injury in older adults: systematic review and meta-analysis

OBJECTIVES

Old age was identified as a strong risk factor for acute kidney injury (AKI). Our objectives were to provide estimates of AKI, risk factors and outcomes in patients ≥ 75 years for whom data are scarce.

METHODS

Observational studies and randomized controlled trials between 2005 and 2021 with patients of mean or median age ≥ 75 years, reporting AKI according to current definitions. Data on AKI incidence, risk factors and mortality were analyzed separately in unselected (UC) and acute heart failure (AHF) cohorts.

RESULTS

Twenty-six observational studies and 4 randomized controlled trials with 51,111 UC and 25,414 AHF patients were included. Ages averaged 79.4 and 79.8 years, respectively. Pooled risk ratios (RRs) of AKI rates were 26.29% (95% confidence intervals (CI) 13.20-41.97) (UC) and 24.21% (95% CI 20.03-28.65) (AHF). In both cohorts, AKI was associated with decreased estimated glomerular filtration rate at baseline, chronic kidney disease (UC: RR 1.80 (95% CI 1.15-2.80), AHF: RR 1.51 (95% CI 1.26-1.95) and hypertension (UC: RR 1.30 (95% CI 1.09-1.56), AHF: RR 1.07 (95% CI 1.05-1.09). RRs of AKI in patients on renin-angiotensin-inhibitors were 0.87 (95% CI 0.78-0.97) and 0.88 (95% CI 0.78-0.98) in UC and AHF, respectively. AKI was consistently associated with increased risk of in-hospital mortality (UC: RR 3.15 (95% CI 2.28-4.35), AHF: RR 4.28 (95% CI 2.53-7.24).

CONCLUSION

AKI is frequent in patients ≥ 75 years. While reduced renal function at baseline, CKD and hypertension were associated with AKI development, renin-angiotensin-inhibitors may be protective. Older AKI patients showed higher short-term mortality rates.

CC Genotype of GNAS c.393C>T (rs7121) Polymorphism Has a Protective Effect against Development of BK Viremia and BKV-Associated Nephropathy after Renal Transplant

The GNAS gene encodes the alpha-subunit of the stimulatory G-protein (Gαs) in humans and mice. The single-nucleotide polymorphism of GNAS, c.393C>T, is associated with an elevated production of Gαs and an increased formation of cyclic adenosine monophosphate (cAMP). In the present study, we analyzed the effect of this GNAS polymorphism on a renal allograft outcome. We screened a cohort of 436 renal allograft recipients, who were retrospectively followed up for up to 5 years after transplant. GNAS genotypes were determined with polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) assays. The 393T allele was detected in 319 (73%) recipients (113 recipients with TT and 206 with CT genotype) and the CC genotype in 117 (27%). The CC genotype was associated with a significantly lower frequency of BK viremia (CC, 17 recipients (15%); T 84 (26%)); p = 0.01; TT, 27 vs. CC, 17, p = 0.07; TT, 27 vs. CT, 57, p = 0. 46; CT, 57 vs. CC, 17, p = 0.01) and BKV-associated nephropathy (CC, 3 recipients (3%); T, 27 (8%); p = 0.03; TT,10 vs. CC, 3, p = 0.04; TT, 10 vs. CT,17, p = 0.85; CT, 17 vs. CC,3, p = 0.04) after transplant. BKV-associated nephropathy-free survival was significantly better among CC genotype carriers than among T allele carriers (p = 0.043; TT vs. CC, p = 0.03; CT vs. CC, p = 0.04; TT vs. CT, p = 0.83). Multivariate analysis indicated an independent protective effect of the CC genotype against the development of both BK viremia (relative risk. 0.54; p = 0.04) and BKV-associated nephropathy after renal transplant (relative risk. 0.27; p = 0.036). The GNAS 393 CC genotype seems to protect renal allograft recipients against the development of BK viremia and BKV-associated nephropathy.

[Nomenclature for kidney function and kidney diseases - Improving assessment and prognosis through precision and comprehensibility]

Nierenkrankheiten stellen ein zunehmendes Gesundheitsproblem dar, dessen Eindämmung eine effektive Kommunikation zwischen den an Erfassung, Diagnostik und Therapie Beteiligten sowie den betroffenen Patientinnen und Patienten erfordert. Die Nomenklatur für Nierenfunktion und Nierenkrankheiten ist jedoch bislang nicht einheitlich. Die internationale, gemeinnützige Organisation Kidney Disease: Improving Global Outcomes (KDIGO) hat deshalb 2019 in einem Konsensus-Prozess ein englischsprachiges Glossar entwickelt, um die Begriffe zur Beschreibung von Nierenfunktion, Nierenstruktur und Nierenkrankheiten zu vereinheitlichen. Leitprinzipien bei der Entwicklung dieser Nomenklatur waren (1) Präzision, (2) Patientenzentrierung und (3) Konsistenz mit bisherigen KDIGO-Leitlinien. Das vorliegende Positionspapier beinhaltet eine deutsche Übersetzung dieses Glossars, die im Auftrag der nephrologischen Fachgesellschaften in Deutschland, Österreich und der Schweiz entwickelt wurde.

Intraoperative hemoadsorption in high-risk patients with infective endocarditis

Background

Postoperative sepsis is an important cause of morbidity and mortality in patients with infective endocarditis undergoing surgical therapy. Blood purification using hemoadsorption therapy shows promising results in the treatment of sepsis. In this study, the clinical effects of intraoperative hemoadsorption in high-risk patients with infective endocarditis were evaluated.

Methods

Eligible candidates were high-risk patients with infective endocarditis undergoing cardiac surgery between January 2014 and December 2019. Patients with intraoperative hemoadsorption (hemoadsorption) were compared to patients without hemoadsorption (control). The endpoints were the incidence of postoperative sepsis, sepsis-associated death and in-hospital mortality. Additionally, postoperative vasopressor need, systemic vascular resistance indices and Sequential Organ Failure Assessment (SOFA) scores were compared.

Results

After propensity score matching, 70 high-risk patients were included. Postoperative sepsis occurred in 14 patients in the hemoadsorption group and in 16 patients in the control group, p = 0.629. Four patients died due to postoperative sepsis in the hemoadsorption group, while 11 postoperative septic patients died in the control group, p = 0.041. In-hospital mortality was 34% in the hemoadsorption group versus 43% in the control group, p = 0.461. On ICU-admission and the first postoperative day, the cumulative vasopressor need was 0.17 versus 0.25 μg/kgBW/min, p = 0.123 and 0.06 versus 0.11 μg/kgBW/min, p = 0.037, and the systemic vascular resistance index was 1448 versus 941 dyn·s·cm-5, p = 0.013 and 1156 versus 858 dyn·s·cm-5, p = 0.110 in the hemoadsorption versus control group, respectively. Postoperative course of SOFA score normalized significantly (p = 0.01) faster in the hemoadsorption group.

Conclusions

In high-risk cardiac surgical patients with infective endocarditis, intraoperative hemoadsorption significantly reduced sepsis-associated mortality. Furthermore, intraoperative hemoadsorption resulted in significant faster recovery of hemodynamics and organ function. Intraoperative hemoadsorption seems to attenuate the severity of postoperative sepsis.

Severe and long-lasting alteration of albumin redox state by plasmapheresis

Plasmapheresis (PE) is an established form of therapeutic apheresis (TA). Purpose of this longitudinal prospective single center study was to investigate the effect of PE on albumin redox state (ARS), as infusion of commercial albumin during PE may alter albumin oxidation which has an impact on its functional properties and oxidative stress level. 43 subjects with autoimmune-mediated neurological disorders were included. 20 subjects in the experimental group received five treatments of PE. 13 subjects received five treatments of immunoadsorption and 10 subjects received no TA as controls. ARS was determined before and after TA and 12 days after the last TA by fractionating it into human mercaptalbumin (HMA), human non-mercaptalbumin 1 (HNA-1), and human non-mercaptalbumin 2 (HNA-2) by high-performance liquid chromatography. Irreversibly oxidised HNA-2 increased over the course of five PE treatments from 2.8% (IQR 1.3–3.7%) to 13.6% (IQR 10.9–15.9) (P < 0.01) and remained elevated 12 days after the last PE procedure (7.7% IQR 7.1–10.5, P < 0.05). The study showed for the first time that PE exerts a severe and long-lasting alteration on ARS indicating a new adverse effect of PE, that may influence oxidative stress level.

MO247: Exogen ATP has a Suppressive Effect on CD4+-T-Cells In Aav-Patients And Healthy Controls

BACKGROUND AND AIMS

Anti-neutrophil-cytoplasmatic-antibody-associated vasculitis (AAV) is a life-threatening autoimmune disease. It is a necrotizing vasculitis of small- and medium-sized vessels. T-cells play a pivotal role in pathogenesis and mediating damage in the vessels. Exogen ATP (adenosine triphosphate) is normally in a low nanomolar range. Under inflammatory conditions, various cells can release ATP to the extracellular department. In this case, ATP is a DAMP (damage-associated molecular pattern), but its effect on disease mechanisms in AAV is not well understood. It is the aim of the study to determine the effect of exogenous ATP on T-cells in healthy controls and AAV-patients.

METHOD

A total of 22 AAV-patients in remission and 13 healthy controls were recruited. Peripheral blood mononuclear cells (PBMC) were isolated and then labeled with a tracking dye. The PBMC were cultured for 3 days with different concentrations of ATP in presence or absence of anti-CD3/CD28 stimulation. After 3 days, the cells were restimulated with PMA/Ionomycin and Brefeldin A for 4 hours. Cytokine production and cell proliferation were assessed by flow cytometry. Baseline was defined as T-cell proliferation in absence of exogenous ATP. The fold change was calculated by: $\frac{{{\rm{T}} - {\rm{cell\ proliferation\ with\ ATP}}}}{{{\rm{T}} - {\rm{cell\ proliferation\ without\ ATP}}}}$ . The P-value for paired values was calculated by the Wilcoxon matched-pairs signed rank test. The P-value for unpaired groups was calculated by the Mann Whitney U-test.

RESULTS

The mean T-cell proliferation of CD4+-T-cells for healthy controls was significantly different comparing 0 µM ATP and 500 µM ATP (mean proliferated fraction, 0 µM ATP versus 500 µM ATP: 40.48% versu 22.58%, P = .0002). In presence of ATP, a suppression of T-cell proliferation was found in patients and healthy controls (patients versus healthy controls, fold change T-cell proliferation from baseline with 50 µM ATP: 0.81 ± 0.03 versus 0.79 ± 0.03, P = .60; 125 µM ATP: 0.75 ± 0.03 versus 0.70 ± 0.04, P = .38; 250 µM ATP: 0.68 ± 0.03 versus 0.59 ± 0.05, P = .17; 500 µM ATP: 0.53 ± 0.03 versus 0.54 ± 0.05, P = .77); the higher the concentration of ATP, the stronger the suppression of proliferation.

IFNγ+-CD4+-T-cells of healthy controls were also suppressed by exogenous ATP (0 µM ATP versus 500 µM ATP, CD4+ T-cells: %IFNγ+: 19.94% versus 10.59%, P = .0002). INFγ production by CD4+-T-cells was reduced after addition of ATP in both patients and healthy controls (patients versus healthy controls, fold change CD4+-IFNγ+ -T-cells from baseline with 50 µM ATP: 0.69 ± 0.04 versus 0.64 ± 0.04, P = 0.45; 125 µM ATP: 0.62 ± 0.04 versus 0.58 ± 0.04, P = .63; 250 µM ATP: 0.62 ± 0.04 versus 0.49 ± 0.04, P = .11; 500 µM ATP: 0.59 ± 0.05 versus 0.51 ± 0.05, P = .56).

CONCLUSION

Exogenous ATP induced suppression of T-cells in healthy controls and might be important for the maintenance of immunotolerance. DAMP-mediated inhibitory mechanisms were functional in AAV-patients in remission.

Development of De Novo Donor-specific HLA Antibodies and AMR in Renal Transplant Patients Depends on CYP3A5 Genotype

BACKGROUND

The single-nucleotide polymorphism CYP3A5 rs776746 is related to a reduction in the metabolizing activity of the CYP3A5 enzyme. People carrying at least one copy of the wild-type allele, defined as CYP3A5 expressers, exhibit higher clearance and lower trough concentrations of tacrolimus than homozygous nonexpressers, and this difference may affect alloimmunization and allograft function.

METHODS

We retrospectively studied 400 kidney transplant recipients treated with a tacrolimus-based immunosuppression regimen to detect CYP3A5 genotype, de novo formation of HLA antibodies and donor-specific antibodies (DSAs), and clinical outcome up to 5 y after transplant.

RESULTS

We found that 69 (17%) of the 400 patients were CYP3A5 expressers. During the first 3 y after transplant, CYP3A5 expressers tended to have lower tacrolimus trough levels than nonexpressers, although their tacrolimus dosage was as much as 80% higher. De novo DSAs were found more frequently in CYP3A5 expressers than in nonexpressers (13/69 [19%] versus 33/331 [10%], P = 0.02). De novo DSA-free survival rates (P = 0.02) were significantly lower for expressers than for nonexpressers. CYP3A5 genotype had no effect on allograft failure, but CYP3A5 expressers exhibited a significantly higher frequency of antibody-mediated rejection. CYP3A5 expresser status was an independent risk factor for the development of de novo DSAs (relative risk, 2.34, P = 0.01).

CONCLUSIONS

Early detection of CYP3A5 expressers, enabling genotype-based dose adjustment of tacrolimus immediately after renal transplant, may be a useful strategy for reducing the risk of de novo DSA production and antibody-mediated rejection.

Chloroquine Suppresses Effector B-Cell Functions and Has Differential Impact on Regulatory B-Cell Subsets

Objectives

Chloroquine (CQ) is approved for treatment of B-cell mediated diseases such as rheumatoid arthritis and systemic lupus erythematosus. However, the exact mode of action in these diseases has not been studied and it remains unclear which effect CQ has on B-cells. Thus, it was the aim of this study to investigate to which extent CQ affects functionality of effector and regulatory B-cell.

Methods

For this purpose, B-cells were isolated from peripheral blood of healthy controls and renal transplant patients. B-cells were stimulated in presence or absence of CQ and Interleukin-10 (IL-10) and Granzyme B (GrB) secretion were assessed. In addition, effector functions such as plasma cell formation, and Immunoglobulin G (IgG) secretion were studied.

Results

CQ suppressed Toll-Like-Receptor (TLR)-9 induced B-cell proliferation in a dose-dependent manner. IL-10^pos regulatory B-cells were suppressed by CQ already at low concentrations whereas anti-IgG/IgM-induced GrB secreting regulatory B-cells were less susceptible. Plasma blast formation and IgG secretion was potently suppressed by CQ. Moreover, purified B-cells from renal transplant patients were also susceptible to CQ-induced suppression of effector B-cell functions as observed by diminished IgG secretion.

Conclusion

In conclusion, CQ had a suppressive effect on IL-10 regulatory B-cells whereas GrB secreting regulatory B-cells were less affected. Effector functions of B-cells such as plasma blast formation and IgG secretion were also inhibited by CQ. Effector B-cells derived from renal transplant patients already under immunosuppression could be suppressed by CQ. These findings may partly explain the clinical efficacy of CQ in B-cell mediated autoimmune diseases. The application of CQ in other disease contexts where suppression of effector B-cells could offer a benefit, such as renal transplantation, may hypothetically be advantageous.

[Treatment and progression management of acute kidney injury]

Acute kidney injury (AKI) represents one of the greatest global health challenges and is associated with high mortality. The often multifactorial etiology and complex pathophysiological mechanisms have so far hampered the development of causal therapeutic options. The treatment should be stage-adapted according to the current KDIGO guideline: avoid nephrotoxicity, optimize volume status and perfusion pressure, monitor serum creatinine, urine output and proteinuria. New insights into the influence of mitochondrial dysfunction and cellular senescence in AKI, well-defined study endpoints, and innovations through nanotechnology may enable targeted drug-based AKI therapy in the future. Especially the weeks following an AKI are a vulnerable phase and crucial for progression management.

Decline of Humoral Responses 6 Months after Vaccination with BNT162b2 (Pfizer–BioNTech) in Patients on Hemodialysis

This study analyzed binding and neutralizing antibody titers up to 6 months after standard vaccination with BNT162b2 (two doses of 30 µg each) in SARS-CoV-2 naïve patients (n = 59) on hemodialysis. Humoral vaccine responses were measured before and 6, 12, and 24 weeks after the first vaccination. A chemiluminescent immunoassay (CLIA) was used to quantify SARS-CoV-2 IgG against the spike glycoprotein. SARS-CoV-2 neutralizing activity was tested against the wild-type virus. A multivariable binary regression model was used to identify risk factors for the absence of humoral immune responses at 6 months. At week 6, vaccine-specific seroconversion was detected in 96.6% of all patients with median anti-SARS-CoV-2 IgGs of 918 BAU/mL. At weeks 12 and 24, seroconversion rates decreased to 91.5% and 79.7%, and corresponding median binding antibody titers declined to 298 BAU/mL and 89 BAU/mL, respectively. Neutralizing antibodies showed a decay from 79.6% at week 6 to 32.8% at week 24. The risk factor with the strongest association for vanishing immune responses was low serum albumin (p = 0.018). Regarding vaccine-specific humoral responses 6 months after the standard BNT162b2 vaccination schedule, SARS-CoV-2 naïve patients receiving hemodialysis must be considered at risk of becoming infected with SARS-CoV-2 and being infectious.

Comparison of Mortality Prediction Scores in Intermediate-Care Patients with Liver Cirrhosis at a German University Transplant Centre: A Prospective Study

BACKGROUND AND AIMS

Mortality prediction models help to extract and relate patient data upon admission to intensive or intermediate care units (ImCUs). Considering technical and economic healthcare developments, re-evaluations of score performances are required to warrant their validity. This study validates and compares established scoring systems in cirrhotic ImCU patients.

METHODS

Acute Physiology and Chronic Health Evaluation (APACHE) II, Simplified Acute Physiology Score (SAPS) 2 and 3, Sepsis Organ Failure Assessment (SOFA), Mortality Probability Model at ICU admission (MPMo) II and III, Model for End stage Liver Disease (MELD), CLIF-Consortium Acute-on-Chronic Liver Failure (CLIF-C ACLF), CLIF-Consortium Acute Decompensation (CLIF-C AD), and Intermediate Care Unit Severity Score (ImCUSS) were calculated in patients with cirrhosis (n = 98) at ImCU admission. Discrimination performances were evaluated by area under the receiver operating characteristic curves (AUROCs), calibration performances with calibration belt plots, and their corresponding p values.

RESULTS

Overall, SAPS 3 and CLIF-C ACLF have shown the best 90-day mortality prediction outcomes with AUROCs of 0.825 and 0.783 along with calibration belt p values of 0.128 and 0.061, respectively. In a subgroup analysis of patients with acute-on-chronic liver failure (ACLF), expanded SAPS 2, SOFA, and SAPS 3 reached the best AUROCs, i.e., 0.760, 0.750, and 0.714, but none of the tested scores reached an acceptable calibration.

CONCLUSION

Ninety-day mortality risk prediction of the SAPS 3 and CLIF-C ACLF was accurate in our cohort of patients with liver cirrhosis admitted to ImCUs. A particular challenge remains that is the mortality prediction in patients with ACLF requiring ImCU-level care; here, further developments are needed to generate scores with acceptable predictive performances.

Differential Treatment Effects for Renal Transplant Recipients With DSA-Positive or DSA-Negative Antibody-Mediated Rejection

Background

Antibody-mediated rejection (ABMR) is the main cause of renal allograft loss. The most common treatment strategy is based on plasmapheresis plus the subsequent administration of intravenous immunoglobulin (IVIG). Unfortunately, no approved long-term therapy is available for ABMR. The current study was designed to analyze the effect of various ABMR treatment approaches on allograft survival and to compare treatment effects in the presence or absence of donor-specific antibodies (DSAs).

Methods

This single-center study retrospectively analyzed 102 renal allograft recipients who had biopsy-proven ABMR after transplant. DSA was detectable in 61 of the 102 patients. Initial standard treatment of ABMR consisted of plasmapheresis (PS) or immunoadsorption (IA), followed by a single course of IVIG. In case of nonresponse or recurrence, additional immunosuppressive medications, such as rituximab, bortezomib, thymoglobulin, or eculizumab, were administered. In a second step, persistent ABMR was treated with increased maintenance immunosuppression, long-term therapy with IVIG (more than 1 year), or both.

Results

Overall graft survival among transplant patients with ABMR was <50% after 3 years of follow-up. Compared to the use of PS/IA and IVIG alone, the use of additional immunosuppressive medications had no beneficial effect on allograft survival (p = 0.83). Remarkably, allografts survival rates were comparable between patients treated with the combination of PS/IA and IVIG and those treated with a single administration of IVIG (p = 0.18). Renal transplant patients with ABMR but without DSAs benefited more from increased maintenance immunosuppression than did DSA-positive patients with ABMR (p = 0.01). Recipients with DSA-positive ABMR exhibited significantly better allograft survival after long-term application of IVIG for more than 1 year than did recipients with DSA-negative ABMR (p = 0.02).

Conclusions

The results of our single-center cohort study involving kidney transplant recipients with ABMR suggest that long-term application of IVIG is more favorable for DSA-positive recipients, whereas intensification of maintenance immunosuppression is more effective for recipients with DSA-negative ABMR.

Predictive role of fluctuating biochemical parameters for mortality in hemodialysis patients

INTRODUCTION

High inflammation parameters like CRP and low albumin levels are considered as risk factors in CKD stage 5 patients. Due to dynamic changes in these parameters, there is evidence of an association between their variation and mortality in hemodialysis patients.

METHODS

We retrospectively analyzed 153 patients on chronic hemodialysis. Dialysis-specific biochemical parameters were measured at three-month intervals over a 42-month period. Fluctuations were calculated as the percentage change in two subsequent measurements.

RESULTS

Median age was 70 years. 41.10% of the patients died over the study period. Higher fluctuation rates in albumin and CRP were significantly associated with a higher mortality rate. Regression analysis revealed that only the fluctuations in albumin proved to be a predictive variable for the end point "death". If the fluctuation in albumin increases by 1%, the mortality risk rises by 22%.

CONCLUSION

Fluctuations in albumin are of predictive importance in patients on chronic hemodialysis.

CXCR4 blockade reduces the severity of murine heart allograft rejection by plasmacytoid dendritic cell-mediated immune regulation

Allograft-specific regulatory T cells (T_reg cells) are crucial for long-term graft acceptance after transplantation. Although adoptive T_reg cell transfer has been proposed, major challenges include graft-specificity and stability. Thus, there is an unmet need for the direct induction of graft-specific T_reg cells. We hypothesized a synergism of the immunotolerogenic effects of rapamycin (mTOR inhibition) and plerixafor (CXCR4 antagonist) for T_reg cell induction. Thus, we performed fully-mismatched heart transplantations and found combination treatment to result in prolonged allograft survival. Moreover, fibrosis and myocyte lesions were reduced. Although less CD3⁺ T cell infiltrated, higher T_reg cell numbers were observed. Noteworthy, this was accompanied by a plerixafor-dependent plasmacytoid dendritic cells-(pDCs)-mobilization. Furthermore, in vivo pDC-depletion abrogated the plerixafor-mediated T_reg cell number increase and reduced allograft survival. Our pharmacological approach allowed to increase T_reg cell numbers due to pDC-mediated immune regulation. Therefore pDCs can be an attractive immunotherapeutic target in addition to plerixafor treatment.

HTK-N as a new preservation solution for human kidney preservation: Results of a pilot randomized controlled clinical phase II trial in living donor transplantation

BACKGROUND

HTK-N was developed based on the traditional HTK preservation solution, resulting in stronger protection against reactive oxygen species as well as better tolerance to hypothermia and ischemia. Aim of the present study was to compare HTK-N to HTK in clinical kidney transplantation demonstrating safety and non-inferiority.

METHODS

We performed a randomized controlled single blinded clinical phase II trial in patients undergoing living donor kidney transplantation. After retroperitoneoscopic nephrectomy kidneys were either perfused and stored with classical HTK solution or the new HTK-N solution. Primary endpoint was the glomerular filtration rate (eGFR according to CKD EPI) 3 months after transplantation. Secondary endpoints included graft and patient survival beside others.

RESULTS

The study included 42 patients, of which 22 were randomized in the HTK-N group and 20 in the HTK group. The primary end point showed a mean eGFR of 55.4 ± 14.0 ml/min/1.73 m² in the HTK group compared to a GFR of 57.2 ± 16.7 ml/min/m² in the HTK-N group (P = .72). Regarding secondary endpoints, there were no apparent differences. Posttransplant graft and patient survival was 100%.

CONCLUSION

This study is the first clinical application of HTK-N for kidney preservation and demonstrates non-inferiority compared to HTK in the setting of living donor kidney transplantation.

Effect of High Dose Active Vitamin D Therapy on the Development of Hypocalcemia After Subtotal Parathyroidectomy in Patients on Chronic Dialysis

Background

The period after parathyroidectomy (PTx) in dialysis patients is characterized by periods of severe hypocalcemia. This study aims to investigate the effect of high doses of active vitamin D immediately after PTx on the development of hypocalcemia.

Materials and Methods

We retrospectively reviewed 111 patients with secondary hyperparathyroidism receiving subtotal PTx between 2010 and 2019. A high dose group “HDG” (n = 67) receiving 12 µg alfacalcidol in combination with 8.550 mg calcium acetate per day, which was then adapted according to lab values, was compared with a low dose group “LDG” (n = 44) receiving up to 4 µg alfacalcidol per day. The laboratory values were recorded up to ten weeks postoperatively.

Results

The assumed drops in parathyroid hormone (PTH) and calcium were observed in both groups after PTx. We observed significantly lower calcium values in the LDG between days 4 and 18 postoperatively than in the HDG (p < 0.001). The proportion of severe hypocalcemia after PTx (total calcium <1.5 mmol/l) in the HDG was 8.5% on day 1 and 47% on day 4 in the LDG. Intravenous calcium requirements were significantly lower in the HDG (7.6%) than in the LDG (45.7%; p = 0.001).

Conclusion

The period after PTx in dialysis patients is characterized by an expected drop in PTH and calcium within the first days. Ongoing high turnover is observed in the 2nd and 3rd week after PTx. Administering high doses of alfacalcidol combined with calcium acetate diminishes the episodes of severe hypocalcemia and the need for intravenous calcium.

ACE2 polymorphism and susceptibility for SARS-CoV-2 infection and severity of COVID-19

OBJECTIVES

The RNA virus severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is responsible for coronavirus disease 2019 (COVID-19). Cell entry is mediated by the human angiotensin-converting enzyme II (ACE2). ACE2 and its close homolog angiotensin-converting enzyme I (ACE) are currently discussed candidate genes, in which single-nucleotide polymorphisms (SNPs) could alter binding or entry of SARS-CoV-2 and enhance tissue damage in the lung or other organs. This could increase the susceptibility for SARS-CoV-2 infection and the severity of COVID-19.

PATIENTS AND METHODS

We performed genotyping of SNPs in the genes ACE2 and ACE in 297 SARS-CoV-2-positive and 253 SARS-CoV-2-negative tested patients. We analyzed the association of the SNPs with susceptibility for SARS-CoV-2 infection and the severity of COVID-19.

RESULTS

SARS-CoV-2-positive and SARS-CoV-2-negative patients did not differ regarding demographics and clinical characteristics. For ACE2 rs2285666, the GG genotype or G-allele was significantly associated with an almost two-fold increased SARS-CoV-2 infection risk and a three-fold increased risk to develop serious disease or COVID-19 fatality. In contrast, the ACE polymorphism was not related to infection risk or severity of disease. In a multivariable analysis, the ACE2 rs2285666 G-allele remained as an independent risk factor for serious disease besides the known risk factors male gender and cardiovascular disease.

CONCLUSIONS

In summary, our report appears to be the first showing that a common ACE2 polymorphism impacts the risk for SARS-CoV-2 infection and the course of COVID-19 independently from previously described risk factors.

Comparison of Humoral and Cellular CMV Immunity in Patients Awaiting Kidney Transplantation

Chronic kidney disease may alter antiviral T cell immunity. In the current study, we assessed in 63 patients prior to kidney transplantation how humoral and cellular immunity against cytomegalovirus (CMV) correlated using an interferon (IFN)-γ ELISpot (T-Track^® CMV, Mikrogen, Neuried, Germany). The cohort comprised 24 patients with negative and 39 with positive CMV IgG. Whereas none of the patients with negative CMV IgG showed detectable responses to the T-Track^® CMV, 26 out of 39 patients with positive CMV IgG had positive ELISpot responses. The median response to CMV pp65 in the CMV seronegative group was 0 spot forming units (SFU) per 200,000 PBMC (range 0–1) and in the seropositive group 43 SFU (range 0–750). Thus, 13 out of 39 patients with positive CMV serostatus (33%) had undetectable T cell immunity and may be at an increased risk of CMV reactivation. CMV pp65-specific ELISpot responses were 29.3-fold higher in seropositive patients with vs. without dialysis and 5.6-fold higher in patients with vs. without immunosuppressive therapy, but patients with dialysis and immunosuppressive therapy showed, as expected, lower responses to phytohemagglutinin, the positive control. This finding may be caused by (subclinical) CMV-DNAemia and a “booster” of CMV-specific T cells.

Autoimmune glomerulonephritis in a multiple sclerosis patient after cladribine treatment

BACKGROUND

Oral cladribine is an approved disease-modifying drug for the treatment of relapsing multiple sclerosis. In controlled clinical trials as well as in post marketing safety assessments, autoimmune conditions have not yet been reported as a specific side effect of cladribine.

OBJECTIVE AND RESULTS

Here, we report a case of anti-glomerular basement membrane antibody-mediated glomerulonephritis that occurred shortly after the fourth cladribine treatment cycle.

CONCLUSION

Neurologists should be attentive to the development of secondary autoimmunity in cladribine-treated patients.

MO096ROLE OF THE ENDOTHELIN SYSTEM IN THE INTERACTIONS OF THE VASOPRESSOR SYSTEMS IN VIVO IN MEN - IMPORTANCE OF GENETIC HOST FACTORS

Background and Aims

Arterial hypertension is one of the most common diseases of the cardiovascular system worldwide and is still the cause of most deaths in Germany. Data on interactions of the endothelin-system with the renin-angiotensin- and the sympathoadrenergic system in the regulation of systemic hemodynamics in humans are lacking. In our present investigation we study the effects of Endothelin A-, Alpha1- and Angiotensin II-type-1-receptor antagonization on the systemic pressor effects of intravenous Endothelin-1-application in young, healthy men. In addition, we analyzed the effects of the genetic variations of the GNB3 C825T-polymorphism on hemodynamic changes. GNB3 825CT/TT-allele-carriers are considered to have a higher risk for multiple diseases with structural, vascular degeneration, such as arterial hypertension, diabetes mellitus and obesity.

Method

21 healthy male volunteers were included in this double- blind, randomized, placebo-controlled cross-over study and were studied on four days. Endothelin-1 (ET-1) (0.5, 1, 2.5, 5 ng/kg/min for 20 min each) was given intravenous 2.0 hours after oral application of either placebo or Doxazosin, 3.5 hours after oral application of Candesartan (Candesartan 8 mg) or in the presence of a continuous infusion of the ET-A-selective antagonist BQ123 (60 μg/min). Blood pressure (BP) and heart rate (HR) were recorded and total peripheral resistance (TPR) was measured using impedance cardiography. ET-1-dose-response curves were analyzed with ANOVA. Data are presented as mean ± SD. Since we suspected an effect of the GNB3 C825T-polymorphism we divided the overall collective into 2 sub-collectives according to the GNB3 C825T-genotypes (n = 21, GNB3 825CC: n = 10, GNB3 825CT/TT: n = 11). Our analyses considered the overall collective and compared the sub-collectives intraday and interday.

Results

ET-1 increased systolic blood pressure (SBD) (p ≤ 0,01), diastolic blood pressure (DBD) and mean arterial pressure (MBP) as well as total peripheral resistance (TPR) (each p ≤ 0,001) with decreasing heart rate (HR5) (p ≤ 0,05). Elevation of blood pressure existed in both sub-collectives (GNB3 825CC: SBD & MBD: p ≤ 0,01, DBP & TPR: p ≤ 0,05, GNB3 825CT/TT: DBD, MBD & TPR: p ≤ 0,01, SBP p ≤ 0,05).

Antagonization of ETA-receptors reversed the effect in the overall collective as well as in the sub-collectives. Both, Doxazosin, as well as Candesartan led to a decrease in blood pressure, however, dose-response relationship was influenced more by doxazosin (DBD: p ≤ 0,001, MBD: p ≤ 0,01) than by candesartan (all values: p &gt; 0,05). For both drugs, blood pressure and TPR remained elevated under maximum ET-1-application compared to baseline measurement. Blood pressure dependent heart rate changes were observed in the overall collective and in GNB3 825CC-allele-carriers under sole ET-1-therapy (p ≤ 0.05) (Fig. 1). Candesartan reversed the effect of ET-1 on the sub-collectives (p &gt; 0.05). GNB3 825CT/TT-allele-carriers showed no reduction in heart rate under ET-1-application, but with accompanying candesartan therapy (p ≤ 0.01) (Fig. 2). The genotype collectives thus behaved oppositely to the drugs in this respect.

Conclusion

In summary, ET-1 increased systolic, diastolic and mean arterial blood pressure as well as systemic vascular resistance. Doxazosin, Candesartan and BQ123 led to a decrease in blood pressure. Blood pressure and TPR remained elevated under maximum ET-1 application plus Candesartan or Doxazosin. The heart rate changes of the genotype-separated sub-collectives were opposite when ET-1 was administered compared to ET-1 and Candesartan.

Primidone blocks RIPK1-driven cell death and inflammation

The receptor-interacting serine/threonine protein kinase 1 (RIPK1) is a key mediator of regulated cell death and inflammation. Recent studies suggest that RIPK1 inhibition would fundamentally improve the therapy of RIPK1-dependent organ damage in stroke, myocardial infarction, kidney failure, and systemic inflammatory response syndrome. Additionally, it could ameliorate or prevent multi-organ failure induced by cytokine release in the context of hyperinflammation, as seen in COVID-19 patients. Therefore, we searched for a RIPK1 inhibitor and present the aromatic antiepileptic and FDA-approved drug primidone (Liskantin®) as a potent inhibitor of RIPK1 activation in vitro and in a murine model of TNFα-induced shock, which mimics the hyperinflammatory state of cytokine release syndrome. Furthermore, we detected for the first time RIPK1 activation in the respiratory tract epithelium of hospitalized patients who tested positive for SARS-CoV-2 infection. Our data provide a strong rationale for evaluating the drug primidone in conditions of hyperinflammation in humans.

Impaired Humoral Response in Renal Transplant Recipients to SARS-CoV-2 Vaccination with BNT162b2 (Pfizer-BioNTech)

The severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) has a major impact on transplant recipients, with mortality rates up to 20%. Therefore, the effect of established messenger RNA (mRNA)-based SARS-CoV-2 vaccines have to be evaluated for solid organ transplant patients (SOT) since they are known to have poor responses after vaccination. We investigated the SARS-CoV-2 immune response via SARS-CoV-2 IgG detection in 23 renal transplant recipients after two doses of the mRNA-based SARS-CoV-2 vaccine BNT162b2 following the standard protocol. The antibody response was evaluated once with an anti-SARS-CoV-2 IgG CLIA 15.8 +/− 3.0 days after the second dose. As a control, SARS-CoV-2 IgG was determined in 23 healthcare workers (HCW) and compared to the patient cohort. Only 5 of 23 (22%) renal transplant recipients were tested positive for SARS-CoV-2 IgG antibodies after the second dose of vaccine. In contrast, all 23 (100%) HCWs were tested positive for antibodies after the second dose. Thus, the humoral response of renal transplant recipients after two doses of the mRNA-based vaccine BNT162b2 (Pfizer-BioNTech, Kronach, Germany) is impaired and significantly lower compared to healthy controls (22% vs. 100%; p = 0.0001). Individual vaccination strategies might be beneficial in these vulnerable patients.

SARS-CoV-2 Seroprevalence in Healthcare Workers in Germany: A Follow-Up Study

SARS-CoV-2 is a worldwide challenge for the medical sector. Healthcare workers (HCW) are a cohort vulnerable to SARS-CoV-2 infection due to frequent and close contact with COVID-19 patients. However, they are also well trained and equipped with protective gear. The SARS-CoV-2 IgG antibody status was assessed at three different time points in 450 HCW of the University Hospital Essen in Germany. HCW were stratified according to contact frequencies with COVID-19 patients in (I) a high-risk group with daily contacts with known COVID-19 patients (n = 338), (II) an intermediate-risk group with daily contacts with non-COVID-19 patients (n = 78), and (III) a low-risk group without patient contacts (n = 34). The overall seroprevalence increased from 2.2% in March-May to 4.0% in June-July to 5.1% in October-December. The SARS-CoV-2 IgG detection rate was not significantly different between the high-risk group (1.8%; 3.8%; 5.5%), the intermediate-risk group (5.1%; 6.3%; 6.1%), and the low-risk group (0%, 0%, 0%). The overall SARS-CoV-2 seroprevalence remained low in HCW in western Germany one year after the outbreak of COVID-19 in Germany, and hygiene standards seemed to be effective in preventing patient-to-staff virus transmission.

Transmembrane serine protease 2 Polymorphisms and Susceptibility to Severe Acute Respiratory Syndrome Coronavirus Type 2 Infection: A German Case-Control Study

The transmembrane serine protease 2 (TMPRSS2) is the major host protease that enables entry of the severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) into host cells by spike (S) protein priming. Single nucleotide polymorphisms (SNPs) in the gene TMPRSS2 have been associated with susceptibility to and severity of H1N1 or H1N9 influenza A virus infections. Functional variants may influence SARS-CoV-2 infection risk and severity of Coronavirus disease 2019 (COVID-19) as well. Therefore, we analyzed the role of SNPs in the gene TMPRSS2 in a German case-control study. We performed genotyping of the SNPs rs2070788, rs383510, and rs12329760 in the gene TMPRSS2 in 239 SARS-CoV-2-positive and 253 SARS-CoV-2-negative patients. We analyzed the association of the SNPs with susceptibility to SARS-CoV-2 infection and severity of COVID-19. SARS-CoV-2-positive and SARS-CoV-2-negative patients did not differ regarding their demographics. The CC genotype of TMPRSS2 rs383510 was associated with a 1.73-fold increased SARS-CoV-2 infection risk, but was not correlated to severity of COVID-19. Neither TMPRSS2 rs2070788 nor rs12329760 polymorphisms were related to SARS-CoV-2 infection risk or severity of COVID-19. In a multivariable analysis (MVA), the rs383510 CC genotype remained an independent predictor for a 2-fold increased SARS-CoV-2 infection risk. In summary, our report appears to be the first showing that the intron variant rs383510 in the gene TMPRSS2 is associated with an increased risk to SARS-CoV-2 infection in a German cohort.

Humoral Response to SARS-CoV-2-Vaccination with BNT162b2 (Pfizer-BioNTech) in Patients on Hemodialysis

mRNA-based SARS-CoV-2 vaccines offer a preventive strategy against severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infections that is of interest in the care of patients on hemodialysis (HDP). We measured humoral immune responses in 72 HDP after standard vaccination with two doses of the mRNA-based SARS-CoV-2 vaccine BNT162b2 (Pfizer-BioNTech). Antibody responses were evaluated with an anti-SARS-CoV-2 IgG ChemiLuminescent ImmunoAssay (CLIA) two weeks after the second dose. In addition, SARS-CoV-2 IgG was determined in a control of 16 healthy healthcare workers (HCW). The control group of HCW has shown a strong antibody response with a median (MD (Q1; Q3)) antibody titer of 800.0 AU/mL (520.5; 800.0). In comparison to HCW, HDP under 60 years of age responded equally (597.0 AU/mL (410.5; 800.0), p = 0.051). However, the antibody responses of the HDP negatively correlated with age (r2 = 0.2954 p < 0.0001), leading to significantly lower antibody titers in HDP over 60 years (280.0 AU/mL (45.7; 477.0), p < 0.0001). To thoroughly understand the immunogenicity of the new mRNA-based vaccines in HDP, longitudinal data on the effectiveness and durability of antibody responses are needed. Modifications of immunization schedules should be considered in HDP with low or without antibody responsiveness after standard vaccination to boost immune reactivity and prolong protective effects in these vulnerable patients.

CD107a+ (LAMP-1) Cytotoxic CD8+ T-Cells in Lupus Nephritis Patients

Cytotoxic CD8+ T-cells play a pivotal role in the pathogenesis of systemic lupus erythematosus (SLE). The aim of this study was to investigate the role of CD107a (LAMP-1) on cytotoxic CD8+ T-cells in SLE-patients in particular with lupus nephritis. Peripheral blood of SLE-patients (n = 31) and healthy controls (n = 21) was analyzed for the expression of CD314 and CD107a by flow cytometry. Kidney biopsies of lupus nephritis patients were investigated for the presence of CD8+ and C107a+ cells by immunohistochemistry and immunofluorescence staining. The percentages of CD107a+ on CD8+ T-cells were significantly decreased in SLE-patients as compared to healthy controls (40.2 ± 18.5% vs. 47.9 ± 15.0%, p = 0.02). This was even more significant in SLE-patients with inactive disease. There was a significant correlation between the percentages of CD107a+CD8+ T-cells and SLEDAI. The evaluation of lupus nephritis biopsies showed a significant number of CD107a+CD8+ T-cells mainly located in the peritubular infiltrates. The intrarenal expression of CD107a+ was significantly correlated with proteinuria. These results demonstrate that CD8+ T-cells of patients with systemic lupus erythematosus have an altered expression of CD107a which seems to be associated with disease activity. The proof of intrarenal CD107a+CD8+ suggests a role in the pathogenesis of lupus nephritis.

Reactivations of Latent Viral Infections Are Associated with an Increased Thr389 p70S6k Phosphorylation in Peripheral Lymphocytes of Renal Transplant Recipients

Reactivations of BK polyoma virus (BKPyV) and human cytomegalovirus (HCMV) frequently cause life- and graft-threatening complications after renal transplantation. Both viruses are dependent on the mTOR pathway for replication. In this study we investigated the association of viral replication with mTOR activity in peripheral lymphocytes of renal transplant recipients. A flow-cytometry based assay for the measurement of Thr389 p70S6k phosphorylation, a surrogate marker of the mTOR pathway was established. Forty-eight adult renal transplant recipients were recruited to measure p70S6k activity in their peripheral blood mononuclear cells. This data set in conjunction with information concerning previous replication of BKPyV and HCMV was examined for correlations. Episodes of BKPyV replication were significantly associated with increased p70S6k phosphorylation in CD4⁺ T lymphocytes (p = 0.0002) and CD19⁺ B lymphocytes (p = 0.0073). HCMV infection of patients with a high-risk HCMV constellation of donor and recipient (D+/R−) was associated with increased p70S6k phosphorylation in CD19⁺ B lymphocytes (p = 0.0325). These associations were found to be independent of the trough levels of the immunosuppressive drugs. Conclusion: P70S6k phosphorylation in peripheral lymphocytes is associated with BKPyV reactivations and to a lesser extent with HCMV infections in renal transplant recipients.

Characterization of follicular T helper cells and donor-specific T helper cells in renal transplant patients with de novo donor-specific HLA-antibodies

T follicular helper (T_FH) cells are a heterogeneous subset of immunocompetent T helper (T_H) cells capable of augmenting B cell responses in lymphoid tissues. In transplantation, exposure to allogeneic tissue activates T_FH cells increasing the risk of the emergence of de novo donor-specific HLA-antibodies (dnDSA). These can cause antibody-mediated rejection (AMR) and allograft loss. Follicular regulatory T (T_FR) cells counteract T_FH cell activity. Here, we investigated the implications of T_FH and T_FR cells on dnDSA formation after renal transplantation (RTX). Considering T_FH cells to be CXCR5⁺ and IL-21⁺, we found by flow cytometry that patients with dnDSA produced IL-21 more abundantly compared to healthy volunteers. In in vitro alloreactivity assays, patients with dnDSA featured an enhanced alloreactive T_H cell pool in response to donor-specific HLA antigens. Besides, longitudinal investigations suggested enhanced alloreactivity shortly after transplantation increasing the risk of dnDSA development. Taken together, in spite of continuous immunosuppression we report a strong IL-21 response in T_FH cells and an expanded reservoir of donor-specific memory T_H cells in patients with dnDSA. This warrants further investigations if aberrant T_FH cell activation may precede the formation of dnDSA promoting AMR.

Registry on extracorporeal multiple organ support with the advanced organ support (ADVOS) system: 2-year interim analysis

The objective of this registry is to collect data on real-life treatment conditions for patients for whom multiple organ dialysis with Advanced Organ Support (ADVOS) albumin hemodialysis is indicated.This registry was performed under routine conditions and without any study-specific intervention, diagnostic procedures, or assessments. Data on clinical laboratory tests, health status, liver function, vital signs, and examinations were collected (DRKS-ID: DRKS00017068). Mortality rates 28 and 90 days after the first ADVOS treatment, adverse events and ADVOS treatment parameters, including treatment abortions, were documented.This analysis was performed 2 years after the first patient was included on January 18, 2017. As of February 20, 2019, 4 clinical sites in Germany participated and enrolled 118 patients with a median age of 60 (IQR: 45, 69) of whom 70 were male (59.3%). Patients had a median SOFA Score of 14 (IQR: 11, 16) and a predicted mortality of 80%. The median number of failing organs was 3 (IQR: 2, 4).Four hundred twenty nine ADVOS treatments sessions were performed with a median duration of 17 hours (IQR: 6, 23). A 5.8% of the ADVOS sessions (25 of 429) were aborted due to device related errors, while 14.5% (62 of 429) were stopped for other reasons. Seventy nine adverse events were documented, 13 of them device related (all clotting, and all recovered without sequels).A significant reduction in serum creatinine (1.5 vs 1.2 mg/dl), blood urea nitrogen (24 vs 17 mg/dl) and bilirubin (6.9 vs 6.5 mg/dl) was observed following the first ADVOS treatment session. Blood pH, bicarbonate (HCO3-) and base excess returned to the physiological range, while partial pressure of carbon dioxide (pCO2) remained unchanged. At the time of the analysis, 28- and 90-day mortality were 60% and 65%, respectively, compared to an expected ICU-mortality rate of 80%. SOFA score was an independent predictor for outcome in a multivariable logistic regression analysis.The reported data show a high quality and completion of all participating centers. Data interpretation must be cautious due to the small number of patients, and the nature of the registry, without a control group. However, the data presented here show an improvement of expected mortality rates. Minor clotting events similar to other dialysis therapies occurred during the treatments.

Pathological findings in rotation thromboelastometry associated with thromboembolic events in COVID-19 patients

Background

Severe thromboembolic events are one of the major complications associated with COVID-19 infection, especially among critically ill patients. We analysed ROTEM measurements in COVID-19 patients with a severe disease course and in patients with severe sepsis.

Methods

In this study, data obtained by extended analysis of haemostasis with standard laboratory tests and thromboelastometry of 20 patients with severe course of COVID-19 were retrospectively analysed and compared with similar data from 20 patients with severe sepsis but no COVID-19.

Results

The thromboelastometry values obtained from 20 sepsis patients contained a maximum clot firmness above the normal range but among COVID-19 patients, hypercoagulability was much more pronounced, with significantly higher maximum clot firmness (FIBTEM: 38.4 ± 10.1 mm vs. 29.6 ± 10.8 mm; P  = 0.012; EXTEM: 70.4 ± 10.4 mm vs. 60.6 ± 14.8 mm; P  = 0.022). Additionally, fibrinogen levels were significantly higher among COVID-19 patients (757 ± 135 mg/dl vs. 498 ± 132 mg/dl, P < 0.0001). Furthermore, thromboelastometry showed fibrinolysis shutdown among COVID-19 patients with significantly lower maximum of lysis than among sepsis patients (EXTEM: 0.6 ± 1.2 % vs. 3.3 ± 3.7 %; P  = 0.013). Seven of 20 COVID-19 patients experienced thromboembolic events, whereas no patient in the sepsis group experienced such events.

Conclusions

ROTEM analysis showed significantly different pathological findings characterized by hypercoagulability and fibrinolysis shutdown among COVID-19 patients with a severe disease course compared to patients with severe sepsis. These abnormalities seem to be associated with thromboembolic events.

Extracorporeal cytokine adsorption: Significant reduction of catecholamine requirement in patients with AKI and septic shock after cardiac surgery

Background

Extracorporeal cytokine adsorption is an option in septic shock as an additional measure to treat a pathological immune response. Purpose of this study was to investigate the effects of extracorporeal cytokine adsorption on hemodynamic parameters in patients with acute kidney injury (AKI) on continuous renal replacement therapy (CRRT) and septic shock after cardiac surgery.

Methods

In this retrospective study, a total of 98 patients were evaluated. Hemoadsorption was performed by the CytoSorb® adsorber. In all patients cytokine adsorption was applied for at least 15 hours and at least one adsorber was used per patient. To compare cumulative inotrope need in order to maintain a mean arterial pressure (MAP) of ≥ 65 mmHg, we applied vasoactive score (VAS) for each patient before and after cytokine adsorption. A paired t-test has been performed to determine statistical significance.

Results

Before cytokine adsorption the mean VAS was 56.7 points. This was statistically significant decreased after cytokine adsorption (27.7 points, p< 0.0001). Before cytokine adsorption, the mean noradrenalin dose to reach a MAP of ≥ 65 mmHg was 0.49 μg/kg bw/min, the mean adrenalin dose was 0.12 μg/kg bw/min. After cytokine adsorption, significantly reduced catecholamine doses were necessary to maintain a MAP of ≥ 65 mmHg (0.24 μg/kg bw/min noradrenalin; p< 0.0001 and 0.07 μg/kg bw/min adrenalin; p < 0.0001). Moreover, there was a significant reduction of serum lactate levels after treatment (p< 0.0001). The mean SOFA-score for these patients with septic shock and AKI before cytokine adsorption was 16.7 points, the mean APACHE II-score was 30.2 points. The mean predicted in-hospital mortality rate based on this SOFA-score of 16.7 points was 77,0%, respectively 73,0% on APACHE II-score, while the all-cause in-hospital mortality rate of the patients in this study was 59.2%.

Conclusion

In patients with septic shock and AKI undergoing cardiac surgery, extracorporeal cytokine adsorption could significantly lower the need for postoperative inotropes. Additionally, observed versus SOFA- and APACHE II-score predicted in-hospital mortality rate was decreased.

Kidney transplantation with allografts from infant donors-Small organs, big value

BACKGROUND

Although infant organ donors remain a rare source of organs for transplantation, technical challenges have resulted in increased rates of complications and inferior graft function. The aim of the present study was to investigate the outcomes of kidneys procured from juvenile and infant donors.

PATIENTS AND METHODS

We evaluated all kidney transplants from deceased donors < 16 years of age performed at our center between 01/2008 and 08/2019. We defined three groups based on quartiles of donor body weight: <13 kg (infant donors), 13-40 kg (juvenile donors), and > 40 kg (standard criteria donors). Clinical characteristics and outcomes were compared between groups.

RESULTS

Ninety-two transplants were included in this study. Out of 92 recipients, there were 32 (34.8%) adult and 60 (65.2%) pediatric patients. All groups demonstrated excellent graft function and survival on both short and long-term follow-up. 1-year, 3-year, and 5-year graft survival rates for the standard criteria donor group were 100%, 95.2%, and 88.4%, respectively, compared with 95.8% for infant and 95% for juvenile donors at all times (P = .79). eGFR at 5 years was 98.9 ± 5.5, 74.1 ± 6.2, and 81.6 ± 6.9 mL/min/1.73 m² for infant, juvenile, and standard criteria donors, respectively (P < .01).

CONCLUSION

Infant donor allografts can be transplanted with excellent long-term outcomes in both pediatric and adult recipients. Implanting them as single allografts onto pediatric candidates allows for the transplantation of two patients. As such, pediatric recipients should be prioritized for these donor organs.

Intraperitoneal ampicillin treatment for peritoneal dialysis- related peritonitis with Listeria monocytogenes - a case report

BACKGROUND

Peritoneal dialysis (PD)-related peritonitis is a rare but serious complication and is associated with increased morbidity and mortality rates. It is most commonly caused by Staphylococcus aureus or Staphylococcus epidermidis, but infection with Listeria monocytogenes may also occur. Recommendations for antibiotic treatment of a Listeria infection are currently based on a small number of case reports and suggest the administration of ampicillin. But unlike vancomycin or gentamicin, for ampicillin the route of application, the dosage, and the duration of treatment have not yet been established. We report a case in which PD-associated peritonitis due to Listeria infection was treated with ampicillin administered intravenously and intraperitoneally, separately and in combination.

CASE PRESENTATION

A 72-year-old man with chronic kidney disease stage 5 dialysis (CKDG5D) secondary to hypertension and diabetes was hospitalised in April 2020 because of PD-related peritonitis caused by a Listeria infection. In accordance with the results of resistance tests, the patient was treated with intravenous ampicillin at a dosage of 6 g twice daily. After initial treatment the leukocyte count in the PD effluent had decreased substantially, but it was permanently reduced only with the addition of intraperitoneal ampicillin (4 g daily). Efficient serum concentrations of ampicillin were determined for both routes of administration, intravenous and intraperitoneal.

CONCLUSION

This is the first case report demonstrating that PD-related peritonitis due to Listeria monocytogenes infection can be treated with intraperitoneal ampicillin and monitored by the determination of peripheral serum concentrations of ampicillin.

The Effects of Intensive Versus Routine Treatment in Patients with Acute Kidney Injury

BACKGROUND

In patients with acute kidney injury (AKI), specialized treatment-initiated in response to an early-warning system- may be beneficial compared with routine treatment.

METHOD

To explore effect estimators in a pilot trial (DRKS00010530), patients with AKI on regular wards of a university hospital were treated either in the usual way (control group) or more intensively (intervention group). The subjects were allotted randomly to the two treatment groups. The more intensive treatment consisted of an early warning system for a rise in the serum creatinine concentration, immediate consultation of a specialist, and the issuance of a patient kidney passport. The primary endpoint was recovery of renal function after AKI during the index hospitalization. Renal complications and process indicators were the secondary endpoints.

RESULTS

The proportion of patients whose renal function returned to baseline after AKI was 50% in the intervention group (N = 26) and 42% in the control group (N = 26) (odds ratio 1.4, 95% confidence interval [0.5; 4.0], p = 0.58). The calculated glomerular filtration rate went down, from hospital admission to discharge, by 3 mL/min/1.73 m2 (1st-3rd quartile: [6; -20]) in the intervention group and by 13 mL/min/1.73 m2 in the control group (1st-3rd quartile: [0; -25]; p = 0.09). Complications of AKI such as hyperkalemia, pulmonary edema, and renal acidosis were rarer in the intervention group (15% versus 39%; p = 0.03). In the intervention group, compared with the control group, the cause of AKI was identified more frequently (27% versus 4%; p = 0.05); drugs with relevance to the kidney were discontinued more frequently (65% versus 31%; p = 0.01); and the diagnosis of AKI was more frequently documented in the patient's chart (58% versus 37%; p = 0.03).

CONCLUSION

Specialized consultations supported by an early warning system for AKI seem to be beneficial for patients. The findings of this pilot trial should be verified in larger-scale randomized controlled trials.