Prognosis of patients with severe hyponatraemia is related not only to hyponatraemia but also to comorbidities and to medical management: results of an observational retrospective study.

BACKGROUND: The true cause of death in severe hyponatraemic patients remains controversial. The present study aimed to analyse the relationship between comorbidity, medical management and prognosis in severe hyponatraemic patients. METHODS: Medical records of all patients hospitalised in our institution in 2012 with a plasma sodium ≤120 mmol/l were retrospectively analysed. RESULTS: One hundred forty-seven of 64 723 adult patients (0.2 %) were identified with severe hyponatraemia. In-hospital mortality rate was 24.5 and 50.3 % after a median follow-up of 431 days. Patients with plasma sodium <110 mmol/l had less comorbidity (Charlson Comorbidity Index 2.2 ± 1.9 vs. 4.0 ± 3.1 (plasma sodium 110-115 mmol/l) and 4.2 ± 3.1 (plasma sodium 116-120 mmol/l); P = .02)) and a small trend for less mortality, respectively 40.0, 51.2 and 52.3 % (P = .64). At discharge, nonsurvivors and survivors had similar plasma sodium with 58.3 % of nonsurvivors being normonatraemic. Urine analysis was performed in 74.2 % of cases and associated with lower in-hospital mortality (20.2 % vs. 36.8 %, P = .05). In multivariate Cox analysis, mortality was significantly associated with plasma sodium normalisation (HR 0.35, P < 0.001), urine analysis (HR 0.48, P = .01), Charlson Comorbidity Index (HR 1.23, P < .001) and serum albumin (HR 0.88, P < .001). CONCLUSION: Mortality in severe hyponatraemia appears mainly due to comorbidities although the latter are potentiated by hyponatraemia itself and its management thereby exacerbating the risk of death.

Enhancing vascular access planning in CKD: validating the 40% KFRE threshold for predicting ESKD in a French retrospective cohort study.

Background: Establishing the optimal timing for creating vascular access in patients with chronic kidney disease (CKD) is a critical and challenging aspect of patient management. The Kidney Disease: Improving Global Outcomes guidelines propose using a 40% 2-year threshold based on the Kidney Failure Risk Equation (KFRE) for this purpose. However, the effectiveness of this threshold compared with traditional methods, such as estimated glomerular filtration rate (eGFR), is not well-established. Methods: In this monocentric retrospective cohort study, we analyzed data from patients referred for vascular mapping before arteriovenous fistula (AVF) creation between April 2013 and June 2023. The study aimed to compare the ≥40% 2-year KFRE threshold with a <15 mL/min/1.73 m² eGFR threshold for predicting end-stage kidney disease (ESKD). We assessed the probability of ESKD, considering death before AVF creation as a competing risk. Discrimination between KFRE and eGFR was evaluated using C-statistics. Results: The study included 238 patients with a mean age of 65.2 years and a mean eGFR of 13.3 mL/min/1.73 m². Over a median follow-up of 10.7 months, 178 patients developed ESKD, and 21 died before ESKD. Probability of ESKD at 1 year was 77.6% (95% CI 69.9%-85.3%) using a ≥40% 4-variable KFRE threshold versus 65.8% (95% CI 58.3%-73.3%) using a <15 mL/min/1.73 m² eGFR threshold. The C-statistics indicated better predictive ability for the 8-variable KFRE at 6 months [0.82 (95% CI 0.76-0.88)], while both 4- and 8-variable KFRE models were effective for 1-year predictions [0.835 (95% CI 0.78-0.89) and 0.82 (95% CI 0.76-0.875), respectively]. Sensitivity and specificity analyses favored the ≥40% KFRE threshold over the eGFR threshold. Conclusions: This study suggests that using a ≥40% 2-year KFRE threshold for planning vascular access in CKD patients is promising and potentially superior to the traditional <15 mL/min/1.73 m² eGFR threshold. This approach may offer a balance between minimizing premature AVF creation and the risk of starting dialysis via a central venous catheter.

Clinical and Prognostic Factors in Patients with IgG4-Related Kidney Disease.

BACKGROUND: IgG4-related kidney disease is a major manifestation of IgG4-related disease, a systemic fibroinflammatory disorder. However, the clinical and prognostic kidney-related factors in patients with IgG4-related kidney disease are insufficiently defined. METHODS: We conducted an observational cohort study using data from 35 sites in two European countries. Clinical, biologic, imaging, and histopathologic data; treatment modalities; and outcomes were collected from medical records. Logistic regression was performed to identify the possible factors related to an eGFR ≤30 ml/min per 1.73 m 2 at the last follow-up. Cox proportional hazards model was performed to assess the factors associated with the risk of relapse. RESULTS: We studied 101 adult patients with IgG4-related disease with a median follow-up of 24 (11-58) months. Of these, 87 (86%) patients were male, and the median age was 68 (57-76) years. Eighty-three (82%) patients had IgG4-related kidney disease confirmed by kidney biopsy, with all biopsies showing tubulointerstitial involvement and 16 showing glomerular lesions. Ninety (89%) patients were treated with corticosteroids, and 18 (18%) patients received rituximab as first-line therapy. At the last follow-up, the eGFR was below 30 ml/min per 1.73 m 2 in 32% of patients; 34 (34%) patients experienced a relapse, while 12 (13%) patients had died. By Cox survival analysis, the number of organs involved (hazard ratio [HR], 1.26; 95% confidence interval [CI], 1.01 to 1.55) and low C3 and C4 concentrations (HR, 2.31; 95% CI, 1.10 to 4.85) were independently associated with a higher risk of relapse, whereas first-line therapy with rituximab was protective (HR, 0.22; 95% CI, 0.06 to 0.78). At their last follow-up, 19 (19%) patients had an eGFR ≤30 ml/min per 1.73 m 2 . Age (odd ratio [OR], 1.11; 95% CI, 1.03 to 1.20), peak serum creatinine (OR, 2.74; 95% CI, 1.71 to 5.47), and serum IgG4 level ≥5 g/L (OR, 4.46; 95% CI, 1.23 to 19.40) were independently predictive for severe CKD. CONCLUSIONS: IgG4-related kidney disease predominantly affected middle-aged men and manifested as tubulointerstitial nephritis with potential glomerular involvement. Complement consumption and the number of organs involved were associated with a higher relapse rate, whereas first-line therapy with rituximab was associated with lower relapse rate. Patients with high serum IgG4 concentrations (≥5 g/L) had more severe kidney disease.

Effects of high- vs low-dose native vitamin D on albuminuria and the renin-angiotensin-aldosterone system: a randomized pilot study.

BACKGROUND: Residual albuminuria is associated with an increased risk of progression to ESKD. We tested whether a supplementation with native vitamin D could reduce albuminuria in stable CKD patients under maximal renin-angiotensin system (RAS) blockade. METHODS: We conducted a randomized controlled study of high (cholecalciferol 100 000 UI per 10 days over 1 month) vs low-dose (ergocalciferol 400 UI/days over 1 month) supplementation with native vitamin D on urinary albumin/creatinine ratio, blood pressure and the RAS over 1 month in stable CKD patients with albuminuria and maximum tolerated RAS blockade. RESULTS: We included 31 patients, 21 in the high dose group and 10 in the low dose group. In contrast with a low dose, high dose vitamin D normalized plasma 25(OH)D, decreased iPTH but slightly increased plasma phosphate. High dose vitamin D decreased geometric mean UACR from 99.8 mg/mmol (CI 95% 60.4-165.1) to 84.7 mg/mmol (CI 95% 51.7-138.8, p = 0.046). In the low dose group, the change in geometric mean UACR was not significant. Blood pressure, urinary 24 h aldosterone and peaks and AUC of active renin concentrations after acute stimulation by a single dose of 100 mg captopril were unaffected by the supplementation in native vitamin D, irrespective of the dose. Native vitamin D supplementation was well tolerated. CONCLUSIONS: We found a small (- 15%) but significant decrease in albuminuria after high dose vitamin D supplementation. We found no effect of vitamin D repletion on blood pressure and the systemic RAS, concordant with recent clinical studies.

Acute kidney injury and acute kidney recovery following Transcatheter Aortic Valve Replacement.

BACKGROUND: Acute kidney injury (AKI) is associated with a dismal prognosis in Transcatheter Aortic Valve replacement (TAVR). Acute kidney recovery (AKR), a phenomenon reverse to AKI has recently been associated with better outcomes. METHODS: Between November 2012 to May 2018, we explored consecutive patients referred to our Heart Valve Center for TAVR. AKI was defined according to the VARC-2 definition. Mirroring the VARC-2 definition of AKI, AKR was defined as a decrease in serum creatinine (≥50%) or ≥25% improvement in GFR up to 72 hours after TAVR. RESULTS: AKI and AKR were respectively observed in 8.3 and 15.7% of the 574 patients included. AKI and AKR patients were associated to more advanced kidney disease at baseline. At a median follow-up of 608 days (range 355-893), AKI and AKR patients experienced an increased cardiovascular mortality compared to unchanged renal function patients (14.6% and 17.8% respectively, vs. 8.1%, CI 95%, p<0.022). Chronic kidney disease, (HR: 3.9; 95% CI 1.7-9.2; p < 0.001) was the strongest independent factor associated with AKI similarly to baseline creatinine level (HR: 1; 95% CI 1 to 1.1 p < 0.001) for AKR. 72-hours post procedural AKR (HR: 2.26; 95% CI 1.14 to 4.88; p = 0.021) was the strongest independent predictor of CV mortality. CONCLUSIONS: Both AKR and AKI negatively impact long term clinical outcomes of patients undergoing TAVR.

Acute renal failure in systemic sclerosis revealing Goodpasture syndrome: "All that glitters is not scleroderma renal crisis".

The most common cause of acute renal failure in systemic sclerosis patients is scleroderma renal crisis but other etiologies have to be considered such as another autoimmune disease. We report the case of a 60-year-old male admitted to our hospital with a renal failure. His medical history included a diagnosis of systemic sclerosis 6 months ago. Antinuclear antibodies were positive at a titer of 1:1280 with positive anti-Scl-70 and anti-myeloperoxidase (34 U/mL) antibodies. Scleroderma renal crisis was suspected. However, antineutrophil cytoplasmic antibody-associated vasculitis could not be excluded and a renal biopsy was performed. Histopathology revealed crescentic glomerulonephritis and rupture of Bowman's capsule. Anti-glomerular basement membrane antibodies were detected in serum and the diagnosis of Goodpasture syndrome was confirmed by kidney's immunofluorescence analysis showing typical deposits. Only three other cases of systemic sclerosis associated with Goodpasture syndrome have been reported in the literature. Also, rapidly progressive glomerulonephritis with positivity of both antineutrophil cytoplasmic antibody and anti-glomerular basement membrane antibodies has been described. Several studies have suggested that antineutrophil cytoplasmic antibody positivity occurs first leading to damages of the glomerular basement membrane, to the release of alpha-3 NC1 antigen, and ultimately to anti-glomerular basement membrane antibody production. Although rare, antineutrophil cytoplasmic antibody-associated vasculitis and Goodpasture syndrome should be searched for in systemic sclerosis patients with acute renal failure.

Bedside Renal Doppler Ultrasonography and Acute Kidney Injury after TAVR.

Acute kidney injury (AKI) following transcatheter aortic valve replacement (TAVR) is associated with a dismal prognosis. Elevated renal resistive index (RRI), through renal Doppler ultrasound (RDU) evaluation, has been associated with AKI development and increased systemic arterial stiffness. Our pilot study aimed to investigate the performance of Doppler based RRI to predict AKI and outcomes in TAVR patients. From May 2018 to May 2019, 100 patients with severe aortic stenosis were prospectively enrolled for TAVR and concomitant RDU evaluation at our institution (Nouvel Hôpital Civil, Strasbourg University, France). AKI by serum Creatinine (sCr-AKI) was defined according to the VARC-2 definition and AKI by serum Cystatin C (sCyC-AKI) was defined as an sCyC increase of greater than 15% with baseline value. Concomitant RRI measurements as well as renal and systemic hemodynamic parameters were recorded before, one day, and three days after TAVR. It was found that 10% of patients presented with AKIsCr and AKIsCyC. The whole cohort showed higher baseline RRI values (0.76 ± 0.7) compared to normal known and accepted values. AKIsCyC had significant higher post-procedural RRI one day (Day 1) after TAVR (0.83 ± 0.1 vs. 0.77 ± 0.6, CI 95%, p = 0.005). AUC for AKIsCyC was 0.766 and a RRI cut-off value of ≥ 0.795 had the most optimal sensitivity/specificity (80/62%) combination. By univariate Cox analysis, Mehran Risk Score, higher baseline right atrial pressure at baseline > 0.8 RRI values one day after TAVR (HR 6.5 (95% CI 1.3-32.9; p = 0.021) but not RRI at baseline were significant predictors of AKIsCyC. Importantly, no significant impact of baseline biological parameters, renal or systemic parameters could be demonstrated. Doppler-based RRI can be helpful for the non-invasive assessment of AKI development after TAVR.

[What is the goal blood pressure in non-diabetic chronic kidney disease?] / Quelles cibles tensionnelles dans la maladie rénale chronique non diabétique ?

High blood pressure during renal disease is highly prevalent and an important risk factor for cardiovascular disease and renal progression. Its optimal management is therefore necessary to improve the prognosis of patients. Several trials concerning the blood pressure target in patients with chronic non-diabetic kidney disease have been published in recent years, we will detail them in this article in order to determine which blood pressure target provides the best benefit in terms of progression of renal diseases and cardiovascular prevention.