Changes of Dissociative Properties of Hemoglobin in Patients with Chronic Kidney Disease.

Background: The ability of hemoglobin to bind and dissociate oxygen is crucial in delivering oxygen to tissues and is influenced by a range of physiological states, compensatory mechanisms, and pathological conditions. This may be illustrated by the oxyhemoglobin dissociation curve (ODC). The key parameter for evaluating the oxygen affinity to hemoglobin is p50. The aim of this study was to evaluate the impact of hemodialysis on p50 in a group of patients with chronic kidney disease (CKD). An additional goal was to assess the correlation between p50 and the parameters of erythropoiesis, point-of-care testing (POCT), and other laboratory parameters. Methods: One hundred and eighty patients (106 male, 74 female), mean age 62.5 ± 17 years, with CKD stage G4 and G5 were enrolled in this cross-sectional study. Patients were divided into two groups, including 65 hemodialysis (HD) patients and 115 patients not receiving dialysis (non-HD). During the standard procedure of arteriovenous fistula creation, blood samples from the artery (A) and the vein (V) were taken for POCT. The causes of CKD, as well as demographic and comorbidity data, were obtained from medical records and direct interviews. Results: The weekly dose of erythropoietin was higher in HD patients than in non-HD patients (4914 ± 2253 UI vs. 403 ± 798 UI, p < 0.01), but hemoglobin levels did not differ between these groups. In the group of non-HD patients, more advanced metabolic acidosis (MA) was found, compared to the group with HD. In arterial and venosus blood samples, the non-HD group had significantly lower pH, pCO2 and HCO3-. This group had a higher proportion of individuals with MA with HCO3- < 22 mmol/L (42% vs. 24%, p < 0.01). The absolute difference of p50 in arterial and venous blood was determined using the formula Δp50 = (p50-A) - (p50-V). Δp50 was significantly higher in the HD group in comparison to non-HD (0.08 ± 2.05 mmHg vs. -0.66 ± 1.93 mmHg, p = 0,02). There was a negative correlation between pH and the p50 value in arterial (pH-A vs. p50-A, r = -0.56, p < 0.01) and venous blood (pH-V vs. p50-V, r = -0.45, p < 0.01). In non-HD patients, hemoglobin levels correlated negatively with p50 (r = -0.29, p < 0.01), whereas no significant relation was found in HD patients. Conclusions: The ODC in pre-dialysis CKD (non-HD) patients is shifted to the right due to MA, and this is an additional factor influencing erythropoiesis. Hemodialysis restores the natural differences in hemoglobin's dissociation characteristics in the arterial and venous circulation.

Clinical Characteristics of EGPA Patients in Comparison to GPA Subgroup with Increased Blood Eosinophilia from POLVAS Registry.

Objective: To characterize the eosinophilic granulomatosis with polyangiitis (EGPA) population from the POLVAS registry depending on ANCA status and diagnosis onset, including their comparison with the granulomatosis with polyangiitis (GPA) subset with elevated blood eosinophilia (min. 400/µl) (GPA HE) to develop a differentiating strategy. Methods: A retrospective analysis of the POLVAS registry. Results: The EGPA group comprised 111 patients. The ANCA-positive subset (n = 45 [40.54%]) did not differ from the ANCA-negative one in clinics. Nevertheless, cardiovascular manifestations were more common in ANCA-negative patients than in those with anti-myeloperoxidase (MPO) antibodies (46.97% vs. 26.92%, p = 0.045). Patients diagnosed before 2012 (n = 70 [63.06%]) were younger (median 41 vs. 49 years, p < 0.01), had higher blood eosinophilia at diagnosis (median 4,946 vs. 3,200/µl, p < 0.01), and more often ear/nose/throat (ENT) and cardiovascular involvement. GPA HE comprised 42 (13.00%) out of 323 GPA cases with reported blood eosinophil count. Both GPA subsets had a lower prevalence of respiratory, cardiovascular, and neurologic manifestations but more often renal and ocular involvement than EGPA. EGPA also had cutaneous and gastrointestinal signs more often than GPA with normal blood eosinophilia (GPA NE) but not GPA HE. The model differentiating EGPA from GPA HE, using ANCA status and clinical manifestations, had an AUC of 0.92, sensitivity of 96%, and specificity of 95%. Conclusion: Cardiovascular symptoms were more prevalent in the ANCA-negative subset than in the MPO-ANCA-positive one. Since EGPA and GPE HE share similarities in clinics, diagnostic misleading may result in an inappropriate therapeutic approach. Further studies are needed to optimize their differentiation and tailored therapy, including biologics.

The clinical complexity among patients with systemic, chronic diseases.

OBJECTIVES: This study aimed to assess the clinical complexity of patients with chronic systemic diseases (systemic lupus erythematosus [SLE] and ANCA-associated vasculitis [AAV]) using the INTERMED Self-Assessment questionnaire (IMSA) to determine the most important factors responsible for this phenomenon in these patients. METHODS: This was a cross-sectional, observational study. Questionnaires were used to evaluate biopsychosocial complexity (IMSA), quality of life (Short Form Survey [SF-36]), mental state (General Health Questionnaire - 28 [GHQ-28] and Hospital Anxiety and Depression Scale [HADS]), and acceptance of illness (Acceptance of Illness Scale [AIS]). RESULTS: The final analysis included 81 patients. There was a moderate correlation between clinical complexity (total IMSA score) and quality of life related to mental health (SF-36) and mental state (GHQ-28) in patients with SLE. However, in patients with AAV, clinical complexity had a strong relationship with physical health-related quality of life and a moderate relationship with mental health-related quality of life. Stepwise regression analysis showed that low mental health-related quality of life is a predictor of higher complexity in SLE. The predictors of high clinical complexity in AAV were low physical and mental health-related quality of life and aggravated depressive symptoms (HADS). Other principal factors of clinical complexity were employment status, place of residence, social functioning, and illness duration. CONCLUSION: This study confirmed the importance of holistic attitudes and complex healthcare among patients with chronic diseases.

Neurotrophin-4 and Brain-Derived Neurotrophic Factor Serum Levels in Renal Transplant Recipients with Chronic Pruritus.

INTRODUCTION: Chronic pruritus (CP) is a common symptom defined as a sensation that provokes the desire to scratch and which lasts for at least 6 weeks. CP remains a problem for up to 21.3% of renal transplant recipients (RTRs). Our research aimed to establish the possible association between serum levels of neurotrophin-4 (NT-4) and brain-derived neurotrophic factor (BDNF) and the presence and intensity of CP in RTR. METHODS: The study was performed on a group of 129 RTRs, who were divided according to the presence or absence of pruritus in the previous 3 days. The assessment of pruritus was performed with the use of a numeric rating scale (NRS), 4-Item Itch Questionnaire (4IIQ), and Itchy Quality of Life (Itchy QoL). A total of 129 blood samples with a volume of 9 ml were drawn from RTRs during the monthly routine control. Serum levels (pg/mL) of NT-4 and BDNF were measured by the ELISA. RESULTS: Pruritic RTRs have statistically significantly higher serum concentrations of NT-4 serum level compared to non-pruritic RTRs (229.17 ± 143.86 pg/mL and 153.08 ± 78.19 pg/mL [p = 0.024], respectively). Moreover, a statistically significant difference between pruritic and non-pruritic RTRs with healthy controls was shown (p < 0.001 and p < 0.001, respectively). Although there was a numerically higher serum concentration of BDNF in pruritic RTRs (32.18 ± 7.31 pg/mL vs. 31.58 ± 10.84 pg/mL), the difference did not reach statistical significance. No statistically significant difference was also seen in BDNF serum levels between RTRs and healthy controls. Furthermore, there was a statistically significant, positive correlation between serum concentration of NT-4 and NRS score (p = 0.008, r = 0.357). CONCLUSIONS: The results indicate higher NT-4 serum concentration in RTRs with pruritus compared to RTRs without pruritus. Furthermore, the study revealed a statistically significant, positive correlation between the serum concentration of NT-4 and NRS score.

Coping of Chronically-Ill Patients during the COVID-19 Pandemic: Comparison between Four Groups.

In many countries, the COVID-19 pandemic led to healthcare reorganization limiting access to diagnostic or therapeutic procedures for chronically-ill patients. In this article, we describe the psychological consequences and coping strategies of several groups of chronically-ill patients. During the cross-sectional survey conducted in 2020, we enrolled 398 patients with four different chronic conditions (psoriasis, multiple sclerosis, and patients who have undergone a kidney transplant or received dialysis). The study sample was examined regarding the experienced stress levels (Perceived Stress Scale) and coping strategies (Brief-COPE). All four groups of patients most commonly declared using problem-focused coping strategies and least commonly reported the use of avoidant coping. Higher levels of perceived stress strongly correlated with self-blaming. The participants who declared previous psychiatric treatment or psychotherapy were more likely to use self-blaming, behavioral disengagement, substance use, and avoidant coping, while previous psychotherapy additionally correlated with emotion-focused coping. Group comparison identifies patients with a chronic neurological disease, such as multiple sclerosis, at higher risk of a less beneficial coping profile than kidney transplant recipients. Further focus on education and early interventions in at-risk individuals is needed, and widely targeted mental health programs are indicated in order to improve the mental health of patients suffering from chronic diseases.

Antiphospholipid Syndrome in Renal Allograft Recipients-A Long-Term Multicenter Analysis.

Antiphospholipid syndrome (APS) is a devastating autoimmune disease and in renal transplant recipients may result in allograft thrombosis or in extra-renal manifestation, mostly venous thromboembolism. There are many non- and immune risk factors affecting renal allograft in recipients with APS. However, renal allograft outcome in recipients with APS without APS nephropathy remains unknown. Aim: The aim of the study was to assess renal allograft function and survival in recipients with APS. Methods: Retrospective, multicenter study included 19 adult renal recipients with definite APS (primary or lupus-related) from three Polish transplant centers. Renal allograft function was assessed using serum creatinine concentration (SCr1) at 3rd month post-transplant and at the end of the observation (SCr2) and glomerular filtration rate (GFR) was estimated based on modification of diet in renal disease (MDRD) formula. General linear model was used to assess 12 month GFR change over time. Kaplan-Meier curves and restricted mean survival time were used for allograft survival. Matched control group consisted of 21 stable renal recipients without history of thrombosis and without anticoagulation/antiplatelet treatment. Results: The study group differs in induction therapy (p = 0.019), high-urgency procedure (p = 0.04), proteinuria (p = 0.0058), primary disease (lupus) (p < 0.0001), re-transplantation in primary APS (p = 0.0046) and shorter time since engraftment to SCr2 (p = 0.016). Primary APS was more often diagnosed post-transplant (p = 0.0005). Allograft biopsy revealed thrombotic microangiopathy (TMA) with acute rejection (AR) or isolated AR vs AR or chronic rejection in controls but did not reach significance (p = 0.054). Renal allograft function was inferior in the study group but did not reach significance: mean SCr2 (mg/dL) was 2.18 ± 1.41 and 1.5 ± 0.68 in controls, respectively, p = 0.27; mean GFR2 (ml/min/1.73m2) was 39.9 ± 20.83 and 51.23 ± 19.03, respectively, p = 0.102. Renal allograft duration was inferior in patients with APS and was (in years) 11.22 ± 1.44 vs. 14.36 ± 0.42, respectively, p = 0.037, in patients with primary APS (p = 0.021), in patients with APS diagnosed post-transplant (p = 0.012) but not in lupus-related APS (p = ns). Fifteen year renal allograft survival was inferior in APS vs. controls (73,86% vs. 90.48%, respectively, p = 0.049). Conclusions: Recipients with APS are at higher risk for allograft loss due to immune and non-immune causes. Renal allograft survival was inferior in recipients with APS and renal function remains impaired but stable.

Rheumatoid arthritis - medication dosage in chronic kidney disease.

Renal failure in the course of rheumatoid arthritis (RA) is a consequence of many factors, including drug-induced nephrotoxicity, comorbidities and chronic inflammation. Contemporary treatment strategies have reduced the incidence of renal failure in the population of RA patients. However, it remains a problem for approximately 25% of patients. Therefore, special attention should be paid to the potential need for dosage modifications of administered medications. Many drugs used in the therapy of rheumatic diseases have not been thoroughly studied for their safety in patients with reduced glomerular filtration, resulting in limited data in this area. The establishment of precise, transparent, and consistent dosage recommendations for antirheumatic drugs in chronic kidney disease would significantly facilitate the care of patients with RA. The following review provides a general summary of the available knowledge regarding the dosage of rheumatic medications in renal insufficiency and aims to highlight the need for further research in this area.

Molnupiravir When Used Alone Seems to Be Safe and Effective as Outpatient COVID-19 Therapy for Hemodialyzed Patients and Kidney Transplant Recipients.

BACKGROUND: Molnupiravir demonstrated an in vitro antiviral activity against positive-sense RNA viruses, including SARS-CoV-2. The study aimed to present the results of outpatient molnupiravir use in kidney transplant recipients and hemodialysis patients during the first months of 2022 in Poland. METHODS: The retrospective observational cohort study at one kidney transplant center included 36 patients diagnosed with COVID-19 with an automated nucleic acid amplification test on nasopharyngeal swab specimens. All patients received molnupiravir for home-based therapy at a dose of 800 mg every 12 h orally for 5 days. Both kidney transplant recipients (n = 16) and hemodialysis patients (n = 20) presented a lot of comorbidities with a Charlson comorbidity index of 4.1 and 5.1, respectively. RESULTS: Patients presented with fever, cough, and weakness followed by muscle and joint pain. Five kidney transplant recipients experienced acute kidney injury with a rise in serum creatinine level from 0.4 to 1.9 mg/dL. No serious side effects of molnupiravir therapy or interactions with immunosuppressive medications were observed. Symptoms of COVID-19 improved rapidly or resolved within 24-48 h of starting treatment. CONCLUSION: The study suggests the safety and efficacy of molnupiravir therapy alone early after the onset of SARS-CoV-2 infection, but further investigations should be performed to confirm our preliminary results. To the best of the authors' knowledge, it is the first published report on molnupiravir use in end-stage kidney disease (ESKD) patients on hemodialysis and the third concerning kidney transplant recipients.

Psychopathological Symptoms Among Chronically Ill Patients During SARS-CoV-2 Pandemic in Poland.

Introduction: The global severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic had a drastic psychological and economic impact on the global population. Having a chronic disease during the pandemic is associated with numerous limitations and challenges like regular hospital visits, access to health-care units and getting specialized treatment. In addition, chronically ill patients are at great risk of acquiring the SARS-CoV-2 virus and at experiencing a more severe course of illness, due to comorbid conditions as well as more frequent encounters with health-care workers and other patients in medical facilities. The aim of this study was to examine the psychological disturbances, during the pandemic in chronically ill patients. Methods: During the cross-sectional survey conducted between May and October 2020, 398 patients with four different chronic conditions (psoriasis, multiple sclerosis and patients who have undergone a kidney transplant or received dialysis). Study sample was examined regarding the occurrence of psychopathological symptoms (General Health Questionnaire 28) and their perceived stress levels (Perceived Stress Scale). Results: The highest scores were found in the MS group and the lowest scores were found in the kidney transplantation group in every subscale of the GHQ-28. Close to half of the studied population (48.74%, n = 193) patients scored above the cut-off for psychopathology. Conclusion: As the study was conducted during the SARS-CoV-2 pandemic in Poland, it stands to reason that the pandemic affected the psychological wellbeing of chronically ill patients. A COVID-19 infection, being quarantined and having had contact with a person who was infected, did not significantly affect the outcome measures; however, further research is needed to explore this topic.

SARS-CoV-2 Infection and Pregnancy: Maternal and Neonatal Outcomes and Placental Pathology Correlations.

There is accumulating evidence on the perinatal aspects of COVID-19, but available data are still insufficient. The reports on perinatal aspects of COVID-19 have been published on a small group of patients. Vertical transmission has been noted. The SARS-CoV-2 genome can be detected in umbilical cord blood and at-term placenta, and the infants demonstrate elevated SARS-CoV-2-specific IgG and IgM antibody levels. In this work, the analysis of clinical characteristics of RT-PCR SARS-CoV-2-positive pregnant women and their infants, along with the placental pathology correlation results, including villous trophoblast immunoexpression status for SARS-CoV-2 antibody, is presented. RT-PCR SARS-CoV-2 amniotic fluid testing was performed. Neonatal surveillance of infection status comprised RT-PCR testing of a nasopharyngeal swab and the measuring of levels of anti-SARS-CoV-2 in blood serum. In the initial study group were 161 pregnant women with positive test results. From that group, women who delivered during the hospital stay were selected for further analysis. Clinical data, laboratory results, placental histomorphology results, and neonatal outcomes were compared in women with immunohistochemistry (IHC)-con SARS-CoV-2-positive and IHC SARS-CoV-2-negative placentas (26 cases). A positive placental immunoprofile was noted in 8% of cases (n = 2), whereas 92% of cases were negative (n = 24). Women with placental infection proven by IHC had significantly different pathological findings from those without. One infected neonate was noted (n = 1; 4%). Infection was confirmed in perinatal autopsy, as there was the intrauterine fetal demise. The potential course of the infection with the risk of vertical transmission and implications for fetal-neonatal condition is critical for proper clinical management, which will involve comprehensive, multidisciplinary perinatal care for SARS-CoV-2-positive patients.

High Serum IL-31 Concentration Is Associated with Itch among Renal Transplant Recipients.

Chronic itch (CI) is a common symptom caused by both dermatological and systemic disorders. CI is also a frequent, burdensome symptom among renal transplant recipients (RTR); however, its pathophysiology is not fully understood. The aim of this study was to assess the differences in concentration of IL-31 among itchy RTR. The study was performed on a group of selected 129 RTRs (54 itchy and 75 non-itchy patients). Itch severity was assessed with the use of the numeral rating scale (NRS) and the 4-item itch questionnaire (4IIQ). Every subject had his blood drawn to measure the concentration of IL-31. The results were subsequently compared and correlated. The mean concentration differed significantly between RTR suffering from itch (602.44 ± 534.5 pg/mL), non-itchy RTR (161.49 ± 106.61 pg/mL), and HC (110.33 ± 51.81 pg/mL) (p < 0.001). Post-hoc analysis revealed a statistically significantly increased IL-31 serum concentration in itchy RTR in comparison to the non-itchy RTR group (p < 0.001) and HC (p < 0.001). No significant difference was observed in IL-31 serum levels between non-itchy RTRs and HC. No correlation between IL-31 and itch intensity was found. The results of our study clearly demonstrate the association between IL-31 levels and CI in patients after renal transplantation.

Biomarkers in Primary Focal Segmental Glomerulosclerosis in Optimal Diagnostic-Therapeutic Strategy.

Focal segmental glomerulosclerosis (FSGS) involves podocyte injury. In patients with nephrotic syndrome, progression to end-stage renal disease often occurs over the course of 5 to 10 years. The diagnosis is based on a renal biopsy. It is presumed that primary FSGS is caused by an unknown plasma factor that might be responsible for the recurrence of FSGS after kidney transplantation. The nature of circulating permeability factors is not explained and particular biological molecules responsible for inducing FSGS are still unknown. Several substances have been proposed as potential circulating factors such as soluble urokinase-type plasminogen activator receptor (suPAR) and cardiolipin-like-cytokine 1 (CLC-1). Many studies have also attempted to establish which molecules are related to podocyte injury in the pathogenesis of FSGS such as plasminogen activator inhibitor type-1 (PAI-1), angiotensin II type 1 receptors (AT1R), dystroglycan(DG), microRNAs, metalloproteinases (MMPs), forkheadbox P3 (FOXP3), and poly-ADP-ribose polymerase-1 (PARP1). Some biomarkers have also been studied in the context of kidney tissue damage progression: transforming growth factor-beta (TGF-ß), human neutrophil gelatinase-associated lipocalin (NGAL), malondialdehyde (MDA), and others. This paper describes molecules that could potentially be considered as circulating factors causing primary FSGS.

Respiratory involvement in antineutrophil cytoplasmic antibody-associated vasculitides: a retrospective study based on POLVAS registry.

OBJECTIVES: The study aimed to characterise the Polish population of (ANCA)-associated vasculitides (AAV) with respiratory involvement (RI), in comparison to the subgroup without lung manifestations and the other cohorts. METHODS: Retrospective analysis of the Polish population of AAV with RI was conducted, based on data from the POLVAS registry. Standard descriptive statistics, χ2 test, and Mann-Whitney U test were used to perform comparisons. RESULTS: Among 461 cases qualified to this study, there were 316 cases with RI (68.5%), 206 with granulomatosis with polyangiitis (GPA) (65.2%), 80 with eosinophilic granulomatosis with polyangiitis (EGPA) (25.3%) and 30 with microscopic polyangiitis (MPA) (9.5%). Proportion of RI in GPA, MPA, and EGPA accounted for 67.8%; 40.0%; 97.6%, respectively. The number of relapses was higher in the RI group (median 1.0 vs. 0.0; p=0.01). In the subgroup of combined GPA and MPA with RI, the trends toward higher proportion of deaths (11.7% vs. 5.7%; p=0.07), relapses requiring hospitalisation (52.2% vs. 42.4%, p=0.07) and relapses requiring admission to the intensive care unit (5.6% vs. 1.4%, p=0.09) were observed, median maximal concentration of CRP was higher (46 vs. 25 mg/l; p=0.01) and more aggressive treatment was administered. CONCLUSIONS: Prevalence of RI in the Polish population of AAV is similar to the values reported in the literature, however, the proportion observed in GPA is closer to those presented in Asian than Western European cohorts. RI seems to be associated with a more severe course of disease and its presence prompts more aggressive treatment.

Are in clinical practice measurements of concentrations and the calculation of mycophenolate mofetil pharmacokinetic parameters needed for optimizing therapy in patients with renal diseases or kidney transplantation?

BACKGROUND: Modern pharmacotherapy requires an individual approach to patients, taking into account changes in pharmacokinetics in pathological states and between-subject variability. This procedure is of particular importance in immunosuppressive drug therapy. In recent years, the attention has been paid to the usefulness of calculating the kinetic parameters of the drug in the optimization of the immunosuppressive treatment. OBJECTIVES: To assess the possibility of using mycophenolic acid (MPA) concentration measurements in order to optimize pharmacotherapy in patients with kidney diseases or after kidney transplantation. MATERIAL AND METHODS: The study included 103 patients with renal diseases (group 1) and after kidney transplantation (group 2), treated at the Department of Nephrology and Transplantation Medicine at the University Clinical Hospital, Wroclaw, Poland. The concentrations of MPA were measured using Enzyme Multiplied Immunoassay Technique (EMIT®) method. A total of 193 pharmacokinetic profiles were performed. RESULTS: The median of initial (C0) concentration for all patients was 2.09 mg/L, in group 1 - 2.06 mg/L and in group 2 - 2.11 mg/L. The median concentration at 30 min after drug administration (C30) was 11.72 mg/L in the whole study group, in group 1 - 11.52 mg/L and in group 2 - 12.72 mg/L. The median concentration at 120 min after the drug administration (C120) was 4.73 mg/L, 4.45 mg/L and 5.57 mg/L, respectively. The median area under the curve from C0 to C120 (AUC)0-120 was 15.77 h × mg/L for the entire study group, in group 1 - 15.46 h × mg/L and in group 2 - 16.78 h × mg/L. Using the Spearman's rank correlation coefficient for both groups, statistically significant (p < 0.05) correlations were found between 1) C0 and C30, 2) C0 and C120, 3) C0 and AUC0-120, 4) C0 and the daily dose, 5) C30 and AUC0-120, and 6) C30 and the morning dose. There were also statistically significant correlations between C120 and AUC0-120. Moreover, in group 1, a statistically significant correlation (p < 0.05) was found between 1) C120 and the daily dose, 2) C120 and albumin, 3) C120 and C30, and 4) C120 and AUC0-120. In the group 2, a statistically significant correlation was found between C120 and the morning dose. CONCLUSIONS: Measurements of MPA concentrations are useful for optimizing immunosuppression in patients requiring an individualized treatment.

Comparing Humoral and Cellular Adaptive Immunity during Convalescent Phase of COVID-19 in Hemodialysis Patients and Kidney Transplant Recipients.

BACKGROUND: It is still unclear whether COVID-19 convalescent kidney transplant recipients (KTR) and hemodialysis (HD) patients can develop anti-SARS-CoV-2 adaptive immunity. The aim was to characterize and compare the immune response to the virus in HD patients and KTR. METHODS: The study included 26 HD patients and 54 KTR-both convalescent (14 HD, 25 KTR) and unexposed. The immune response was assessed by determining the anti-SARS-CoV-2 antibodies in serum and specific T cell response via the interferon-gamma release assay (IGRA). Moreover, blood-morphology-derived parameters, immune cell phenotypes, and acute phase reactants were evaluated. RESULTS: KRT and HD convalescents presented similar serum levels of anti-SARS-CoV-2 IgG and IgA. A negative correlation occurred between IgG and time after the infection was observed. There was a strong relationship between the prevalence of anti-SARS-CoV-2 cellular and humoral responses in both groups. Convalescent IGRA response was significantly higher in HD patients compared to KTR. CONCLUSIONS: HD patients and KTR develop humoral and cellular responses after COVID-19. The antibodies levels are similar in both groups of patients. SARS-CoV-2-reactive T cell response is stronger in HD patients compared to KTR. The SARS-CoV-2-specific IgG level decreases with time while IgA and a cellular response are maintained. IGRA proved to be a valuable test for the assessment of specific cellular immunity in immunocompromised HD patients and KTR.

Clinical and Histopathological Factors Influencing IgA Nephropathy Outcome.

IgA nephropathy (IgAN) is the most frequent primary glomerulonephritis worldwide. Due to its heterogenicity, there is a need to establish robust biomarkers for IgAN, to support treatment decisions and evaluate the risk of progression to end-stage renal disease. Using both clinical and histopathological data, derived from renal biopsies, we aimed to find predictors of renal function deterioration and proteinuria reduction. Clinical and histopathological data of 80 patients with biopsy proven IgAN were analyzed. In a multivariate logarithmic regression model, the presence of endocapillary hypercellularity (E1) predicted a decline in estimated glomerular filtration rate (eGFR)of at least 50% with an odds ratio (OR) of 15.2, whereas serum albumin concentration had a negative influence on eGFR deterioration (OR 0.2). In the second multivariate model, the extent of interstitial fibrosis predicted the worsening of eGFR by 50% (OR 1.1) and serum albumin concentration had a protective impact (OR 0.1). In the univariate logarithmic regression, both the extent of interstitial fibrosis and the presence of endocapillary hypercellularity negatively correlated with the reduction in proteinuria below 1.0 g/24 h with an OR of 0.2 and 0.9, respectively. In our paper, we confirmed the utility of histopathological variables, especially endocapillary hypercellularity and interstitial fibrosis, and clinical parameters, particularly serum albumin concentration, in the prediction of both a decline in eGFR and a reduction in proteinuria in IgA nephropathy.

Immune Cells Profiling in ANCA-Associated Vasculitis Patients-Relation to Disease Activity.

Antineutrophil cytoplasmic antibody (ANCA)-associated vasculitides (AAV) are a group of necrotizing multiorgan autoimmune vasculitides that predominantly affect small blood vessels and are associated with the presence of ANCAs. The aim was to assess regulatory and effector cell populations accompanied by the suPAR biomarker level and link the so-defined immune state to the AAV disease activity. The research involved a multicomponent description of an immune state encompassing a range of B and T cell subsets such as transitional/regulatory B cells (CD19+CD24++CD38++), naïve B cells (CD19+CD24INTCD38INT), Th17 cells, T regulatory cells (CD4+CD25+FoxP3+) and cytotoxic CD4+CD28- cells by flow cytometry. The suPAR plasma level was measured by ELISA. The results indicate that AAV is associated with an increased suPAR plasma level and immune fingerprint characterized by an expansion of Th17 cells and T cells lacking the costimulatory molecule CD28, accompanied by a decrease of regulatory populations (Tregs and transitional B cells) and NK cells. Decreased numbers of regulatory T cells and transitional B cells were shown to be linked to activation of the AAV disease while the increased suPAR plasma level-to AAV-related deterioration of kidney function. The observed immune fingerprint might be a reflection of peripheral tolerance failure responsible for development and progression of ANCA-associated vasculitides.

Vascular Access Perspectives in Patients After Kidney Transplantation.

Introduction: More attention has been paid to the influence of arteriovenous fistula (AVF) on the cardiovascular system. In renal transplant recipients, some beneficial effect of an elective vascular access (VA) ligation was observed in patients with a high AVF flow. However, this strategy is not widely accepted and is in contradiction to the rule of vasculature preservation for possible future access. The aim of our study is to elucidate the vascular access function and VA perspective in the kidney transplantation (KTx) population. Materials and Methods: KTx patients with a stable graft function were recruited to participate in this single center observational study (NCT04478968). The measurement of VA flow and vessel mapping for future vascular access was performed by a color Doppler ultrasound. The study group included 99 (63%) males and 58 (37%) females; the median age was 57 (IQR 48-64) years. The median time from the transplantation to the baseline visit was 94 (IQR 61-149) months. Median serum creatinine concentration was 1.36 (IQR 1.13-1.67) mg/dl. Results: Functioning VA was found in 83 out of 157 (52.9%) patients. The sites were as follows: snuffbox in six (7.2%), wrist in 41 (49.4%), distal forearm in 18 (21.7%), middle or proximal forearm in eight (9.6%), upper-arm AV graft in one (1.2%), and upper-arm AVFs in nine (10.8%) patients, respectively. Blood flow ranged from 248 to 7,830 ml/min; the median was 1,134 ml/min. From the transplantation to the study visit, 66 (44.6%) patients experienced access loss. Spontaneous thrombosis was the most common, and it occurred in 60 (90.9%) patients. The surgical closure of VA was performed only in six (4%) patients of the study group with a functioning VA at the time of transplantation. Access loss occurred within the 1st year after KTx in 33 (50%) patients. Majority (50 out of 83, 60.2%) of the patients with an active VA had options to create a snuffbox or wrist AVF on the contralateral extremity. In a group of 74 patients without a functioning VA, the creation of a snuffbox or wrist AVF on the non-dominant and dominant extremity was possible in seven (9.2%) and 40 (52.6%) patients, respectively. In 10 (13.1%) patients, the possibilities were limited only to the upper-arm or proximal forearm VA on both sides. Access ligation was considered by 15 out of 83 (18.1%) patients with a patent VA. Conclusions: In the majority of the patients, vascular access blood flow was below the threshold of the negative cardiovascular effect of vascular access. Creation of a distal AVF is a protective measure to avoid a high flow and preserve the vessels for future access. The approach to VA should be individualized and adjusted to the patient's profile.

Exhausted Capacity of Bicarbonate Buffer in Renal Failure Diagnosed Using Point of Care Analyzer.

BACKGROUND: Metabolic acidosis in patients with chronic kidney disease (CKD) is a common complication. A bicarbonate concentration in venous blood (V-HCO3-) is a key index for diagnosis and treatment initiation. The aim of our study is to evaluate usability of acid-base balance parameters of in blood taken simultaneously from peripheral artery and the vein. METHODS: A total of 49 patients (median age 66 years [interquartile range IQR 45-75]), with CKD stage G4 or G5 were enrolled in this cross-sectional study. All patients were qualified for arteriovenous fistula creation in pre-dialysis period. The samples were taken during surgery, directly after dissection, and evaluated in a point of care testing analyzer. The arteriovenous difference in bicarbonate levels (Δ-HCO3-) was calculated. According to glomerular filtration rate (eGFR) the group was divided into Group A eGFR ≥ 10 mL/min/1.73 m2) and Group B eGFR < 10 mL/min/1.73 m2). RESULTS: In Group A Δ-HCO3- was significantly higher compared to Group B. No such differences were observed in the case of V-HCO3-. Δ-HCO3- positively correlated with eGFR. The discriminative power of Δ-HCO3- for predicting eGFR < 10 mL/min/1.73 m2 was 0.72 (95% confidence interval [CI] = 0.551-0.88; p = 0.01) which provided 67% sensitivity and 75% specificity. The best cut-off was 0.5 mmol/L. CONCLUSIONS: The Δ-HCO3- lower than 0.5 mmol/L may be used as predictor of exhaust buffer capacity. The value of this tool should be tested in larger population.