Long-term outcome of kidney function in patients with ANCA-associated vasculitis.

BACKGROUND: Kidney involvement is common in anti-neutrophil cytoplasm antibody-associated vasculitis (AAV) and the prognosis is determined by the severity of kidney damage. This study focused on long-term kidney outcomes, defining possible risk factors and comparing the performance of three different histological classifications to predict outcomes for patients with AAV. METHODS: The dataset included 848 patients with newly diagnosed AAV who participated in seven randomized controlled trials (RCTs) (1995-2012). Follow-up information was obtained from questionnaires sent to the principal investigators of the original RCTs. RESULTS: The cumulative incidence of end-stage kidney disease (ESKD) at 5 and 10 years was 17% and 22%, respectively. Patients who developed ESKD had reduced patient survival compared with those with preserved kidney function (hazard ratio 2.8, P < .001). Comparing patients with AAV and kidney involvement with a matched general population, patients with AAV had poor survival outcomes, even in early stages of chronic kidney disease. The main cause of death was infection followed by cardiovascular disease in patients developing ESKD and malignancy in those who did not. Some 34% of patients with initial need for dialysis recovered kidney function after treatment. Thirty-five out of 175 in need of kidney replacement therapy (KRT) during follow-up received a kidney transplant with good outcome; there was 86% patient survival at 10 years.In the subcohort of 214 patients with available kidney biopsies, three scoring systems were tested: the Berden classification, the Renal Risk Score and the Mayo Clinic Score. The scores highlighted the importance of normal glomeruli and severe glomerulosclerosis on kidney survival (P < .001 and P = .001, respectively). The Renal Risk Score demonstrated a moderate prediction of kidney survival (area under the curve 0.79; standard error 0.03, 95% confidence interval 0.71-0.83). CONCLUSIONS: Early diagnosis of AAV is extremely important. Even milder forms of kidney involvement have an impact on the prognosis. Patients in need of KRT had the lowest survival rates, but kidney transplantation has shown favorable outcomes for eligible AAV patients. The three histologic scoring systems were all identified as independent prognostic factors for kidney outcome.

Longevity of anti-spike and anti-nucleocapsid antibodies after COVID-19 in solid organ transplant recipients compared to immunocompetent controls.

Solid organ transplant recipients (SOTRs) are on lifelong immunosuppression, which may interfere with adaptive immunity to COVID-19. The data on dynamics and duration of antibody response in SOTRs are limited. This longitudinal study examined the longevity of both anti-spike (S)- and anti-nucleocapsid (N)-specific IgG antibodies after COVID-19 in SOTRs compared to matched immunocompetent persons. SOTRs (n = 65) were matched with controls (n = 65) for COVID-19 disease severity, age, and sex in order of priority. Serum-IgG antibodies against N and S antigens of SARS-CoV-2 were analyzed. At 1 and 9 months after COVID-19, anti-S-IgG detectability decreased from 91% to 82% in SOTRs versus 100% to 95% in controls, whereas the anti-N-IgG decreased from 63% to 29% in SOTRs versus 89% to 46% in controls. A matched paired analysis showed SOTRs having significantly lower levels of anti-N-IgG at all time points (1 month p = .007, 3 months p < .001, 6 months p = .019, and 9 months p = .021) but not anti-S-IgG at any time points. A mixed-model analysis confirmed these findings except for anti-S-IgG at 1 month (p = .005) and identified severity score as the most important predictor of antibody response. SOTRs mount comparable S-specific, but not N-specific, antibody responses to SARS-CoV-2 infection compared to immunocompetent controls.

COVID-19 in solid organ transplant recipients: A national cohort study from Sweden.

Solid organ transplant (SOT) recipients run a high risk for adverse outcomes from COVID-19, with reported mortality around 19%. We retrospectively reviewed all known Swedish SOT recipients with RT-PCR confirmed COVID-19 between March 1 and November 20, 2020 and analyzed patient characteristics, management, and outcome. We identified 230 patients with a median age of 54.0 years (13.2), who were predominantly male (64%). Most patients were hospitalized (64%), but 36% remained outpatients. Age >50 and male sex were among predictors of transition from outpatient to inpatient status. National early warning Score 2 (NEWS2) at presentation was higher in non-survivors. Thirty-day all-cause mortality was 9.6% (15.0% for inpatients), increased with age and BMI, and was higher in men. Renal function decreased during COVID-19 but recovered in most patients. SARS-CoV-2 antibodies were identified in 78% of patients at 1-2 months post-infection. Nucleocapsid-specific antibodies decreased to 38% after 6-7 months, while spike-specific antibody responses were more durable. Seroprevalence in 559 asymptomatic patients was 1.4%. Many patients can be managed on an outpatient basis aided by risk stratification with age, sex, and NEWS2 score. Factors associated with adverse outcomes include older age, male sex, greater BMI, and a higher NEWS2 score.

Aerobic exercise capacity is maintained over a 5-year period in mild-to-moderate chronic kidney disease: a longitudinal study.

BACKGROUND: Aerobic exercise capacity is reduced in non-dialysis chronic kidney disease (CKD), but the magnitude of changes in exercise capacity over time is less known. Our main hypothesis was that aerobic ExCap would decline over 5 years in individuals with mild-to-moderate CKD along with a decline in renal function. A secondary hypothesis was that such a decline in ExCap would be associated with a decline in muscle strength, cardiovascular function and physical activity. METHODS: We performed a 5-year-prospective study on individuals with mild-to-moderate CKD, who were closely monitored at a nephrology clinic. Fiftytwo individuals with CKD stage 2-3 and 54 age- and sex-matched healthy controls were included. Peak workload was assessed through a maximal cycle exercise test. Muscle strength and lean body mass, cardiac function, vascular stiffness, self-reported physical activity level, renal function and haemoglobin level were evaluated. Tests were repeated after 5 years. Statistical analysis of longitudinal data was performed using linear mixed models. RESULTS: Exercise capacity did not change significantly over time in either the CKD group or controls, although the absolute workloads were significantly lower in the CKD group. Only in a CKD subgroup reporting low physical activity at baseline, exercise capacity declined. Renal function decreased in both groups, with a larger decline in CKD (p = 0.05 between groups). Peak heart rate, haemoglobin level, handgrip strength, lean body mass and cardiovascular function did not decrease significantly over time in CKD individuals. CONCLUSIONS: On a group level, aerobic exercise capacity and peak heart rate were maintained over 5 years in patients with well-controlled mild-to-moderate CKD, despite a slight reduction in glomerular filtration rate. In line with the maintained exercise capacity, cardiovascular and muscular function were also preserved. In individuals with mild-to-moderate CKD, physical activity level at baseline seems to have a predictive value for exercise capacity at follow-up.

The impact of symptoms on health-related quality of life in elderly pre-dialysis patients: effect and importance in the EQUAL study.

BACKGROUND: Quality of life (QoL) is an important outcome in chronic kidney disease (CKD). Patients feel that symptoms are an important determinant of QoL. However, this relation is unknown. The aims of this study were to investigate the impact of the number and severity of symptoms on QoL in elderly pre-dialysis patients, assessed by both the effect of symptoms and their importance relative to kidney function, and other clinical variables on QoL. METHODS: The European Quality study (EQUAL study) is an ongoing European prospective follow-up study in late Stage 4/5 CKD patients aged ≥65 years. We used patients included between March 2012 and December 2015. Patients scored their symptoms with the Dialysis Symptom Index, and QoL with the research and development-36 (RAND-36) item Health Survey (RAND-36). The RAND-36 results in a physical component summary (PCS) and a mental component summary (MCS). We used linear regression to estimate the relation between symptoms and QoL at baseline and after 6 months, and to calculate the variance in QoL explained by symptoms. RESULTS: The baseline questionnaire was filled in by 1079 (73%) patients (median age 75 years, 66% male, 98% Caucasian), and the follow up questionnaire by 627 (42%) patients. At baseline, every additional symptom changed MCS with -0.81 [95% confidence interval (CI): -0.91 to -0.71] and PCS with -0.50 (95% CI: -0.62 to -0.39). In univariable analyses, number of symptoms explained 22% of MCS variance and 11% of PCS variance, whereas estimated glomerular filtration rate only explained 1%. CONCLUSIONS: In elderly CKD Stage 4/5 patients, symptoms have a substantial impact on QoL. This indicates symptoms should have a more prominent role in clinical decision-making.

Early Changes in Monocyte Adhesion Molecule Expression and Tumor Necrosis Factor-α Levels in Chronic Kidney Disease - A 5-Year Prospective Study.

BACKGROUND: Despite the absence of clinical symptoms, patients with chronic kidney disease (CKD) exhibit elevated levels of pro-inflammatory markers. To investigate whether it is possible to detect inflammatory activity and altered monocyte function at an early stage of renal disease, we studied patients with CKD stages 2-3 over 5 years. METHODS: The expression of adhesion molecules on monocytes at resting state and after stimulation with formyl-methionyl-leucyl-phenylalanine (fMLP), as well as oxidative metabolism capacity was measured with flow cytometry in 108 CKD patients and healthy controls. Soluble markers of inflammation, such as cytokines, were analyzed using the Milliplex technique. RESULTS: Patients showed significantly lower CD11b expression after stimulation during the 3rd (p = 0.002) and the 5th year (p < 0.001), together with a lower oxidative burst in response to fMLP over time (p = 0.02). The expression of CD62L on resting monocytes was lower during the 3rd (p = 0.001) and the 5th (p = 0.001) year in patients. Levels of tumor necrosis factor-α and RANTES were significantly increased (p = 0.001, p = 0.006) and interleukin-12 levels were also higher in CKD patients during the 5th year (p = 0.007). CONCLUSION: Monocytes in CKD stages 2-3 show emerging functional abrasions, with altered adhesion molecule expression and impaired fMLP response. These findings suggest that a transformation of monocyte function occurs at an early phase of renal impairment and may together with increased plasma levels of pro-inflammatory cytokines contribute to the higher vulnerability of CKD patients to comorbidities, such as infections and cardiovascular disease.

COVID-19 Outcomes and Vaccinations in Swedish Solid Organ Transplant Recipients 2020-2021: A Nationwide Multi-Register Comparative Cohort Study.

Increased COVID-19-related morbidity and mortality have been reported in solid organ transplant recipients (SOTRs). Most studies are underpowered for rigorous matching. We report infections, hospitalization, ICU care, mortality from COVID-19, and pertinent vaccination data in Swedish SOTRs 2020-2021. We conducted a nationwide cohort study, encompassing all Swedish residents. SOTRs were identified with ICD-10 codes and immunosuppressant prescriptions. Comparison cohorts were weighted based on a propensity score built from potential confounders (age, sex, comorbidities, socioeconomic factors, and geography), which achieved a good balance between SOTRs and non-SOTR groups. We included 10,372,033 individuals, including 9073 SOTRs. Of the SARS-CoV-2 infected, 47.3% of SOTRs and 19% of weighted comparator individuals were hospitalized. ICU care was given to 8% of infected SOTRs and 2% of weighted comparators. The case fatality rate was 7.7% in SOTRs, 6.2% in the weighted comparison cohort, and 1.3% in the unweighted comparison cohort. SOTRs had an increased risk of contracting COVID-19 (HR = 1.15 p < 0.001), being hospitalized (HR = 2.89 p < 0.001), receiving ICU care (HR = 4.59 p < 0.001), and dying (HR = 1.42 p < 0.001). SOTRs had much higher morbidity and mortality than the general population during 2020-2021. Also compared with weighted comparators, SOTRs had an increased risk of contracting COVID-19, being hospitalized, receiving ICU care, and dying. In Sweden, SOTRs were vaccinated earlier than weighted comparators. Lung transplant recipients had the worst outcomes. Excess mortality among SOTRs was concentrated in the second half of 2021.

[Patients with IgA nephropathy often develop terminal uraemia]. / Patienter med IgA-nefropati utvecklar ofta terminal njursvikt.

IgA nephropathy is the most common form of inflammatory kidney disease causing uraemia world-wide and initially often a silent disease with microscopic haematuria as the only clinical finding. If left untreated, progress to terminal uraemia and dialysis is not uncommon as at least 30 % develop end stage renal failure. Awareness of the existence of the disease among GPs, internists and urologists may be helpful, not disregarding microscopic haematuria, particularly in combination with albuminuria or finding of renal casts in the urine, especially in younger individuals. No diagnostic marker in blood or urine for the disease has yet been established so kidney biopsy is still needed to confirm diagnosis. The degree of renal dysfunction, hypertension, albuminuria, and histology findings at time of diagnosis have significant impact on renal outcome. Potential biomarkers for progressive disease have been described but no one has so far been implicated in clinical practice. Until now, the only evidence-based medication consists of blockers of the renin-angiotensin-system and corticosteroids. However, new and potentially more specific drugs are under clinical investigation. Early intervention is mandatory to prevent disease progression. Thus, we want to alarm other specialists to an increased alertness for this disease, referring patients at an early stage of possible IgA nephropathy to the nephrologist for diagnosis and interventions.

Cardiovascular changes in patients with mild-to-moderate chronic kidney disease compared with healthy subjects: a 5-year follow-up study.

BACKGROUND: There is limited knowledge about how cardiovascular parameters change over time in patients with mild-to-moderate chronic kidney disease (CKD). We studied several cardiovascular biomarkers over a 5-year period in patients with mild-to-moderate CKD and in healthy controls. METHODS: Fifty-four patients with CKD stages 2-3 and 54 controls were included. The CKD patients were closely monitored and well controlled for hypertension and other cardiovascular risk factors. Ambulatory blood pressure (BP) monitoring, ankle-brachial index (ABI), carotid and cardiac ultrasound (including measurement of the left ventricular mass index (LVMI)), and biochemical analyses were evaluated. RESULTS: Renal function decreased in both groups, with no significant difference in the change over time. In the CKD patients, none of the BP variables increased over time, but in the controls, average 24-h and daytime systolic BP increased significantly. ABI increased slightly in the CKD patients (P<0·001), but not in the controls (P = 0·963), and phosphate had a significant positive effect on ABI. Although in the CKD patients, there was no significant increase over time in common carotid artery diameter (P = 0·274), there was a small but significant increase in the controls (P = 0·001). LVMI increased significantly over time in both groups. CONCLUSIONS: In our study of patients with mild-to-moderate CKD, the progression of cardiovascular changes over time was relatively slow. Good BP control and treatment of other risk factors may have contributed to slow the progress of cardiovascular involvement, which emphasizes the importance of dedicated care in this population.

Associations of Fibroblast Growth Factor 23 with Markers of Inflammation and Leukocyte Transmigration in Chronic Kidney Disease.

BACKGROUND: Patients with chronic kidney disease (CKD) show elevated levels of inflammatory markers and have an increased risk of infections as well as cardiovascular morbidity. Recent studies have implied effects of fibroblast growth factor 23 (FGF23) on inflammation in CKD. We analyzed potential correlations between levels of FGF23 with pro-inflammatory chemokines and markers of leukocyte transmigration in CKD patients. METHODS: One hundred three patients with CKD 2-5ND and 54 healthy controls, had biochemical markers in blood and urine analyzed according to routine protocol. Pro-inflammatory cytokines were analyzed by Milliplex technique and leukocyte CD11b adhesion molecule expression was measured by flow cytometry. FGF23 levels were measured with ELISA technique. Treatment of leukocytes from healthy blood donors with FGF23 was performed in vitro and effects analyzed by flow cytometry. RESULTS: Tumor necrosis factor-alpha, RANTES and interleukin (IL)-12 levels were significantly higher (p = 0.001, p < 0.001, and p < 0.001) in patients with CKD. Elevated FGF23 levels in the CKD group correlated to glomerular filtration rate, parathyroid hormone, urinary albumin excretion and phosphate as well as to IL-12 and RANTES. CD11b expression on resting granulocytes and monocytes, and on activated monocytes, was associated with FGF23. In vitro treatment of leukocytes with FGF23 reduced CD11b expression in resting as well as in formyl-methyinoyl-leucyl-phenylalanine-stimulated granulocytes (p = 0.03). CONCLUSION: FGF23 levels are associated with various inflammatory markers such as pro-inflammatory cytokines and adhesion molecules on innate immune cells. However, further studies are warranted to define the direct role of FGF23 in modulation of the innate immune system in CKD.

Aspects of carotid structure and function in health and different stages of chronic kidney disease.

INTRODUCTION: Arterial remodelling and stiffening have been demonstrated in end-stage renal disease (ESRD). The presence of vascular alterations in earlier-stage chronic kidney disease (CKD) is less studied. We evaluated vascular structure and function in mild-to-moderate CKD (stages 2-3) compared with healthy subjects and advanced CKD (stages 4-5). METHODS: Carotid ultrasound was performed in 103 non-dialysis CKD patients and 54 healthy controls. Carotid intima-media thickness (CIMT) and common carotid artery (CCA) diameter were measured. Strain, stiffness and the pressure-strain elastic modulus (Ep ) of the right CCA were calculated. RESULTS: There was no significant difference in CCA diameter between CKD 2-3 and controls. The CCA diameter was larger in CKD 4-5 compared with CKD 2-3 and controls (CKD 4-5, 6·50 ± 0·79 mm versus CKD 2-3, 6·08 ± 0·56 mm, P = 0·003; and versus controls 5·97 ± 0·53 mm, P<0·001). However, after adjustments, the difference in CCA diameter was valid only for older ages and also dependent on systolic blood pressure (SBP). There were no significant differences in CIMT, strain or stiffness between the groups, but Ep was higher in CKD 4-5 compared with controls (P = 0·006). CONCLUSION: In mild-to-moderate CKD, there were no significant differences in carotid artery structure or function compared with healthy subjects. Only patients with advanced CKD and older ages showed signs of arterial remodelling. Our study indicates that vascular alterations occur in advanced CKD, with SBP and age as important contributing factors.

Gradual reduction in exercise capacity in chronic kidney disease is associated with systemic oxygen delivery factors.

BACKGROUND: The cause of reduced exercise capacity (ExCap) in chronic kidney disease (CKD) is multifactorial. The aim of this study was to investigate determinants of aerobic ExCap in patients with mild to severe CKD not undergoing dialysis. METHODS: We included 52 individuals with CKD stage 2-3, 47 with stage 4-5, and 54 healthy controls. Peak workload and peak heart rate (HR) were assessed by a maximal cycle exercise test. Cardiac function including stroke volume (SV) and vascular stiffness were evaluated by ultrasound at rest. Handgrip strength, body composition, haemoglobin level and self-reported physical activity were assessed. RESULTS: Peak workload (221±60, 185±59, 150±54 W for controls, CKD 2-3 and CKD 4-5 respectively), peak HR (177±11, 161±24, 144±31 beats/min) and haemoglobin level (14.2±1.2, 13.5±1.4, 12.2±1.3 g/dL) were all three significantly lower in CKD 2-3 than in controls, (p = 0.001, 0.001 and 0.03 respectively) and were even lower in stages 4-5 CKD than in CKD 2-3 (p = 0.01, 0.001 and <0.001 respectively). Resting SV and lean body mass did not differ between groups and handgrip strength was significantly lower only in CKD 4-5 compared to controls (p = 0.02). Peak workload was strongly associated with the systemic oxygen delivery factors: SV, peak HR and haemoglobin level. These three factors along with age, sex and height2 explained 82% of variation in peak workload. Peak HR contributed most to the variation; the peripheral variables handgrip strength and vascular stiffness did not improve the explanatory value in regression analysis. CONCLUSIONS: In this cross-sectional study of CKD patients not on dialysis, aerobic ExCap decreased gradually with disease severity. ExCap was associated mainly with systemic oxygen delivery factors, in particular peak HR. Neither muscle function and mass, nor vascular stiffness were independent determinants of aerobic ExCap in this group of CKD patients.

Cardiac remodelling and functional alterations in mild-to-moderate renal dysfunction: comparison with healthy subjects.

INTRODUCTION: Left ventricular (LV) hypertrophy (LVH) and reduced LV function correlate with poor prognosis in patients with chronic kidney disease (CKD). Our aim is to investigate whether mild-to-moderate CKD is associated with cardiac abnormalities. METHODS: Echocardiography, including tissue Doppler imaging, was performed in 103 patients with CKD at stages 2-3 and 4-5, and in 53 healthy controls. The systolic (s') and diastolic myocardial velocity (e'), and the transmitral diastolic flow velocity (E) were measured, and E/e' was calculated. RESULTS: Patients with chronic kidney disease had higher mean E/e' than controls (mean E/e': controls 5·00 ± 1·23 versus CKD 4-5 6·36 ± 1·71, P<0·001 and versus CKD 2-3 5·69 ± 1·47, P = 0·05), indicating altered diastolic function in the patients. The CKD groups showed lower longitudinal systolic function than controls, as assessed by atrio-ventricular plane displacement and s' (mean s': controls 11·5 ± 1·9 cm s(-1) versus CKD 4-5 10·4 ± 2·1 cm s(-1) , P = 0·03 and versus CKD 2-3 10·4 ± 2·1 cm s(-1) , P = 0·02). The prevalence of LVH was higher in patients with CKD than in controls (controls 13% versus CKD 4-5 37%, P = 0·006 and versus CKD 2-3 30%, P = 0·03). CONCLUSION: Alterations in systolic and diastolic myocardial function can be seen in mild-to-moderate CKD compared with controls, indicating that cardiac involvement starts early in CKD, which may be a precursor of premature cardiac morbidity.