An Unusual Case of Seronegative Cryoglobulinemic Glomerulonephritis with Dominant Organized IgA Deposits Associated with Staphylococcal Infection: Casual or Causal Relationship?

Introduction: Cryoglobulinemia refers to the presence of cryoglobulins (CGs) in the serum, encompassing a group of diseases caused by the type of circulating GC. Cryoglobulinemic glomerulonephritis (CryoGN) is the principal manifestation of renal involvement. The diagnosis may be challenging because the hallmark of cryoglobulinemia is the detection of CG in the serum. However, cases of CryoGN without serological evidence of CGs are not uncommon in clinical practice, often diagnosed by anatomopathological findings in the renal biopsy. Case Presentation: We report the case of an 86-year-old male who developed renal impairment, nephritic syndrome, and nephrotic-range proteinuria, without serological evidence of CGs, associated with staphylococcal bacteremia without apparent focus. Renal biopsy and pathological examination showed a membranoproliferative glomerulonephritis pattern with CD61-negative pseudothrombi. Immunofluorescence microscopy showed atypical IgA-dominant deposits. Electron microscopy revealed amorphous subendothelial and mesangial deposits and organized electrodense deposits within capillary loops (pseudothrombi) with microtubular substructure measuring 20-40 nm in thickness. These findings were consistent with seronegative CryoGN and microtubular organized atypical IgA-dominant deposits. Discussion: In this report, we discuss the clinical, analytical, and histopathological findings of a rare case of CryoGN without serological evidence of CGs. Regarding the etiology that triggered the glomerular disease in our patient, we conducted an exhaustive study in order to determine the underlying cause of CryoGN. At the time of biopsy, the patient had an active staphylococcal bacteremia. There are reports that postulate that staphylococcal antigens drive activation of immune system and in consequence, could cause this rare form of IgA-dominant glomerulonephritis with cryoglobulinemic features. After ruling out other causes of cryoglobulinemia, we discuss a plausible causal relationship of the staphylococcal infection in the pathogenesis of CryoGN in our patient.

Expanded hemodialysis: what's up, Doc?

In recent years there has been an increasing interest in expanded hemodialysis (HDx), an emerging renal replacement therapy based on the use of medium cut-off membranes (MCO). Thanks to the internal architecture of these types of membranes, with a higher pore size and smaller fiber inner diameter to favor internal filtration rate, they can increase the removal of larger middle molecules in conventional hemodialysis. Secondarily, several reports suggest that this therapy potentially improve the outcomes for end-stage renal disease patients. However, HDx has not been defined yet and the characteristics of MCO membranes are not well stablished. The aim of this narrative review is to define HDx and summarize the dialyzers that have been used so far to perform this therapy, collect the evidence available on its efficacy and clinical outcomes compared with other hemodialysis techniques and settle the bases for its optimal prescription.

Efficacy and Safety of the Use of SGLT2 Inhibitors in Patients on Incremental Hemodialysis: Maximizing Residual Renal Function, Is There a Role for SGLT2 Inhibitors?

SGLT-2i are the new standard of care for diabetic kidney disease (DKD), but previous studies have not included patients on kidney replacement therapy (KRT). Due to their high risk of cardiovascular, renal complications, and mortality, these patients would benefit the most from this therapy. Residual kidney function (RKF) conveys a survival benefit and cardiovascular health among hemodialysis (HD) patients, especially those on incremental hemodialysis (iHD). We retrospectively describe the safety and efficacy of SGLT2i regarding RKF preservation in seven diabetic patients with different clinical backgrounds who underwent iHD (one or two sessions per week) during a 12-month follow-up. All patients preserved RKF, measured as residual kidney urea clearance (KrU) in 24 h after the introduction of SGLT2i. KrU levels improved significantly from 4.91 ± 1.14 mL/min to 7.28 ± 1.68 mL/min at 12 months (p = 0.028). Pre-hemodialysis blood pressure improved 9.95% in mean systolic blood pressure (SBP) (p = 0.015) and 10.95% in mean diastolic blood pressure (DBP) (p = 0.041); as a result, antihypertensive medication was modified. Improvements in blood uric acid, hemoglobin A1c, urine albumin/creatinine ratio (UACR), and 24 h proteinuria were also significant. Regarding side effects, two patients developed uncomplicated urinary tract infections that were resolved. No other complications were reported. The use of SGLT2i in our sample of DKD patients starting iHD on a 1-2 weekly regimen appears to be safe and effective in preserving RKF.

Serum chloride as a marker of cardiovascular and all-cause mortality in chronic hemodialysis patients: 5-Year follow-up study.

BACKGROUND: Hypochloremia has been associated with increased mortality in patients with hypertension, heart failure, sepsis, and chronic kidney disease (CKD). The pathophysiological mechanisms of this finding are not clear. There are no studies describing an association between serum chloride levels (Cl-) and mortality in incident chronic hemodialysis (HD) patients. METHOD: Retrospective cohort study of the incident population in our chronic outpatient hemodialysis program between January 1, 2016, and January 1, 2021 (N=374). Survival time was collected in all patients and analyzed using the Kaplan-Meyer method. A multivariate Cox regression model was performed to predict the probability of survival, applying a stepwise procedure. RESULTS: During the median follow-up period of 20 months, 83 patients died. The 5-year overall survival rate for our patients was 45%. Both natremia and chloremia had no significant differences when compared by sex, vascular access, or etiology. There was an inverse correlation between Cl- and interdialytic weight gain (r=-0.15) (p=0.0038). Patients belonging to the quartile with lower Cl- levels had less probability of survival than patients in the quartile with higher Cl- levels (27% and 68%, respectively, p=0.019). On the other hand, in the multivariate Cox regression model, variables significantly associated with higher mortality were being older, having higher baseline comorbidity by modified Charlson index, not taking diuretics and having lower albumin and chloride levels. Particularly, higher Cl- levels was independently associated with both lower all-cause mortality (adjusted hazard ratio [HR]=0.84; 95% confidence interval [CI], 0.77-0.92; p=0.0001) and cardiovascular mortality (HR 0.9; 95% CI, 0.83-0.97; p<0.0057). CONCLUSIONS: Lower Cl- levels were associated with higher all-cause and cardiovascular mortality in incident patients on chronic hemodialysis in our health area.

Efficacy and Safety of Semaglutide, a Glucagon-Like Peptide-1 Receptor Agonist in Real-Life: A Case Series of Patients in Maintenance Incremental Hemodialysis.

The glucagon-like peptide-1 receptor agonists (GLP-1RA) are among the newest treatment options available for managing of type 2 diabetes mellitus and slowing the progression of diabetes kidney disease (DKD). Subcutaneous (SC) semaglutide (Ozempic®) is a GLP-1RA with an extended half-life of approximately 1 week. GLP-1RA are highly effective in improving glycemic control and also show other beneficial effects such as increased natriuresis; decreased blood pressure and albuminuria; reduction of oxidative stress and inflammation; delay of gastric emptying and suppress appetite; the latter may result in significant weight loss. GLP-1RA can be used in patients with advanced-stage CKD; the European Medicines Agency has approved the use of all commercially available human GLP-1 analogs up to a minimal eGFR of 15 mL/min/1.73 m2. However, studies of safety and use of these agents in renal replacement therapy are scarce. Therefore, herein we present 3 cases of patients with advanced DKD in maintenance incremental hemodialysis with 1 session per week to describe the efficacy and safety of the SC semaglutide treatment and the favorable effects on glycemic control, lowering HbA1c, albuminuria, weight, blood pressure control, and preservation of residual kidney function (RKF) during a 6-month follow-up in a hospital hemodialysis unit in Spain. These effects could produce an improvement in morbidity and mortality and could also prevent albuminuria and preserve the RKF. This may allow our patients to maintain a weekly hemodialysis session and could facilitate their inclusion in the kidney transplant waiting lists.

Silent challenge: Early kidney transplant failure and cardiomyopathy.

Differentiation of hypertrophic cardiomyopathy phenotypes is challenging but crucial for appropriate management. We report a case of myocardial oxalate deposition as an infrequent cause of infiltrative cardiomyopathy.

Inflammation and hemodialysis adequacy: are C-reactive protein levels influenced by the dose of dialysis?

INTRODUCTION: Chronic inflammation and the underlying cardiovascular comorbidity are still current problems in chronic hemodialysis patients. There are few studies comparing the "dialysis dose" with the degree of inflammation in the patient. Our main objective was to determine whether there is a relationship between serum C-reactive protein (CRP) levels and the "dialysis dose" (Kt / V) using ionic dialysance. METHODS: Multicenter cross-sectional study. 536 prevalent chronic hemodialysis patients were included. CRP levels, neutrophil-lymphocyte ratio (NLR) and platelet-lymphocyte ratio (PLR) were collected. Kt was obtained by ionic dialysance and urea distribution volume was calculated from the Watson's formula. The sample was divided into two groups, taking the median CRP as the cut-off point. Dialysis adequacy obtained in each group was compared. Finally, a logistic regression model was carried out to determine the variables with the greatest influence. RESULTS: Median CRP was 4.10 mg/L (q25-q75: 1.67-10) and mean Kt/V was 1.48 ± 0.308. Kt/V was lower in the patients included in the high inflammation group (p = 0.01). In the multivariate logistic regression, the "high" levels of CRP were directly correlated with the Log INL (p < 0.001) and inversely proportional with serum albumin values (p = 0.014), Kt/V (p = 0.037) and serum iron (p < 0.001). CONCLUSION: The poorer adequacy in terms of dialysis doses, lower Kt / V values, may contribute to a higher degree of inflammation in chronic hemodialysis patients.

The impact of the correction of hyponatremia during hospital admission on the prognosis of SARS-CoV-2 infection.

Background: SARS-CoV-2 infection is frequently associated with hyponatremia (plasma sodium <135 mmol/L), being associated with a worse prognosis. The incidence of hyponatremia is estimated to be 20-37% according to the series, but there are no data on the prognosis after correction of hyponatremia. Therefore, our objectives were: to analyse the incidence and severity of hyponatremia at hospital admission, and to determine the association of this hyponatremia with the prognosis of COVID-19. Methods: Observational and retrospective cohort study. Patients who were admitted with a diagnosis of COVID-19 infection and hyponatremia, in the period March-May 2020, were included. We recorded epidemiological, demographic, clinical, biochemical, and radiological variables of SARS-CoV-2 infection and hyponatremia at the time of diagnosis and during hospitalization. The clinical follow-up ranged from admission to death or discharge. Results: 91 patients (21.8%) of the 414 admitted for SARS-CoV-2 infection presented hyponatremia (81.32% mild hyponatremia, 9.89% moderate and 8.79% severe). The absence of correction of hyponatremia 72-96 h after hospital admission was associated with higher mortality in patients with COVID-19 (Odds Ratio 0.165; 95% confidence interval: 0.018-0.686; p = 0.011). 19 patients (20.9%) died. An increase in mortality was observed in patients with severe hyponatremia compared with moderate and mild hyponatremia during hospital admission (37.5% versus 11.1% versus 8.1%, p = 0.041). Conclusion: We conclude that persistence of hyponatremia at 72-96 h of hospital admission was associated with higher mortality in patients with SARS-Cov-2.

Introduccion: La infección por SARS-CoV-2 se asocia con frecuencia con hiponatremia (sodio plasmático <135 mmol/l), relacionándose con peor pronóstico. La incidencia de la hiponatremia se estima en 20­37% según las series, pero no existen datos sobre el pronóstico tras la corrección de la hiponatremia. Por ello, nuestros objetivos fueron: analizar la incidencia y gravedad de la hiponatremia al ingreso hospitalario, y determinar la asociación de dicha hiponatremia con el pronóstico del COVID-19. Material y método: Estudio de cohorte observacional y retrospectivo. Se incluyeron pacientes que ingresaron con diagnóstico de infección por COVID-19 e hiponatremia, en el periodo marzo-mayo 2020. Registramos variables epidemiológicas, demográficas, clínicas, analíticas y radiológicas de la infección por SARS-CoV-2 e hiponatremia al momento del diagnóstico y durante la hospitalización. El seguimiento clínico comprendió desde el ingreso hasta el exitus o el alta. Resultados: 91 pacientes (21,8%) de los 414 ingresados por infección del SARS-CoV-2 presentaron hiponatremia (81,32% hiponatremia leve, 9,89% moderada y 8,79% grave). La ausencia de corrección de la hiponatremia a las 72­96 horas del ingreso hospitalario estuvo asociado a mayor mortalidad en los pacientes con COVID-19 (OR 0,165; 95% intervalo de confianza: 0,018­0,686; p = 0,011). Fallecieron 19 pacientes (20,9%). Se observó un aumento de la mortalidad en pacientes con hiponatremia grave en comparación con hiponatremia moderada y leve durante el ingreso (37,5% versus 11,1% versus 8,1%, respectivamente, p = 0,041). Conclusiones: La persistencia de la hiponatremia tras las primeras 72­96 horas del ingreso hospitalario fue asociada a mayor mortalidad+- en los pacientes con SARS-Cov-2.

Impacto de la corrección temprana de la hiponatremia en el pronóstico de la infección del síndrome respiratorio agudo grave del coronavirus 2 (SARS-CoV-2) / The impact of the correction of hyponatremia during hospital admission on the prognosis of SARS-CoV-2 infection

IntroducciónLa infección por el coronavirus del síndrome respiratorio agudo grave de tipo 2 (SARS-CoV-2) se asocia con frecuencia con hiponatremia (sodio plasmático<135mmol/l), relacionándose con peor pronóstico. La incidencia de la hiponatremia se estima en 20-37% según las series, pero no existen datos sobre el pronóstico tras la corrección de la hiponatremia. Por ello, nuestros objetivos fueron: analizar la incidencia y gravedad de la hiponatremia al ingreso hospitalario y determinar la asociación de dicha hiponatremia con el pronóstico de la enfermedad por coronavirus de 2019 (COVID-19).Material y métodoEstudio de cohorte observacional y retrospectivo. Se incluyeron pacientes que ingresaron con diagnóstico de infección por COVID-19 e hiponatremia en el periodo marzo-mayo de 2020. Registramos variables epidemiológicas, demográficas, clínicas, analíticas y radiológicas de la infección por SARS-CoV-2 e hiponatremia en el momento del diagnóstico y durante la hospitalización. El seguimiento clínico comprendió desde el ingreso hasta el exitus o el alta.ResultadosNoventa y un pacientes (21,8%) de los 414 ingresados por infección del SARS-CoV-2 presentaron hiponatremia (81,32% hiponatremia leve, 9,89% moderada y 8,79% grave). La ausencia de corrección de la hiponatremia a las 72-96horas del ingreso hospitalario estuvo asociado a mayor mortalidad en los pacientes con COVID-19 (odds ratio 0,165; 95% intervalo de confianza: 0,018-0,686; p=0,011). Fallecieron 19 pacientes (20,9%). Se observó un aumento de la mortalidad en pacientes con hiponatremia grave en comparación con hiponatremia moderada y leve durante el ingreso (37,5% versus 11,1% versus 8,1%, respectivamente; p=0,041).ConclusionesLa persistencia de la hiponatremia tras las primeras 72-96horas del ingreso hospitalario se asoció a mayor mortalidad en los pacientes con SARS-CoV-2. (AU)

IntroductionSARS-CoV-2 infection is frequently associated with hyponatremia (plasma sodium<135mmol/L), being associated with a worse prognosis. The incidence of hyponatremia is estimated to be 20–37% according to the series, but there are no data on the prognosis after correction of hyponatremia. Therefore, our objectives were: to analyze the incidence and severity of hyponatremia at hospital admission, and to determine the association of this hyponatremia with the prognosis of COVID-19.Material and methodObservational and retrospective cohort study. Patients who were admitted with a diagnosis of COVID-19 infection and hyponatremia, in the period March–May 2020, were included. We recorded epidemiological, demographic, clinical, biochemical, and radiological variables of SARS-CoV-2 infection and hyponatremia at the time of diagnosis and during hospitalization. The clinical follow-up ranged from admission to death or discharge.Results91 patients (21.8%) of the 414 admitted for SARS-CoV-2 infection presented hyponatremia (81.32% mild hyponatremia, 9.89% moderate and 8.79% severe). The absence of correction of hyponatremia 72–96h after hospital admission was associated with higher mortality in patients with COVID-19 (Odds Ratio .165; 95% confidence interval: .018-.686; P=.011). 19 patients (20.9%) died. An increase in mortality was observed in patients with severe hyponatremia compared with moderate and mild hyponatremia during hospital admission (37.5% versus 11.1% versus 8.1%, P=.041).ConclusionsWe conclude that persistence of hyponatremia at 72–96h of hospital admission was associated with higher mortality in patients with SARS-CoV-2. (AU)

Inflamación y adecuación de la hemodiálisis: ¿están los niveles de proteína C reactiva influidos por la dosis de diálisis recibida? / Inflammation and hemodialysis adequacy: Are C-reactive protein levels influenced by dialysis dose?

Introducción : La inflamación crónica y la subyacente comorbilidad cardiovascular aún son problemas vigentes en los pacientes en hemodiálisis crónica. Existen pocos estudios que comparen la «dosis de diálisis» (Kt/V) con el grado de inflamación del paciente. Nuestro objetivo principal fue determinar si existe una relación entre los niveles séricos de proteína C reactiva (PCR) y el Kt/V utilizando la dialisancia iónica.Métodos : Estudio transversal multicéntrico. Se incluyeron 536 pacientes prevalentes en hemodiálisis crónica. Se recogieron los niveles de PCR, el índice neutrófilo-linfocito y el índice plaqueta-linfocito. Se obtuvo el Kt por dialisancia iónica y el volumen de distribución de la urea mediante la fórmula de Watson. Se dividió la muestra en 2 grupos tomando como punto de corte la mediana de PCR y se comparó la adecuación de diálisis en cada uno. Finalmente, se realizó un modelo de regresión logística para determinar las variables de mayor influencia.Resultados : La mediana de PCR fue 4,10mg/L (q25-q75: 1,67-10). El Kt/V medio fue de 1,48±0,308. El Kt/V fue menor en los pacientes incluidos en el grupo de inflamación alta (p=0,01). En la regresión logística multivariante, los niveles «altos» de PCR tuvieron una correlación directa con el Log índice neutrófilo-linfocito (p<0,001) e inversamente proporcional con los valores de albúmina sérica (p=0,014), Kt/V (p=0,037) y hierro sérico (p<0,001).Conclusión : La peor adecuación en términos de dosis de diálisis (valores de Kt/V más bajos) puede contribuir a un mayor grado de inflamación en los pacientes en hemodiálisis crónica. (AU)

Introduction : Chronic inflammation and the underlying cardiovascular comorbidity are still current problems in chronic hemodialysis patients. There are few studies comparing the “dialysis dose” (Kt/V) with the degree of inflammation in the patient. Our main objective was to determine whether there is a relationship between serum C-reactive protein (CRP) levels and the Kt/V using ionic dialysance.Methods : Multicenter cross-sectional study. A total of 536 prevalent chronic hemodialysis patients were included. CRP levels, neutrophil-lymphocyte ratio and platelet-lymphocyte ratio were collected. Kt was obtained by ionic dialysance and urea distribution volume was calculated from the Watson's formula. The sample was divided into 2 groups, taking the median CRP as the cut-off point. Dialysis adequacy obtained in each group was compared. Finally, a logistic regression model was carried out to determine the variables with the greatest influence.Results : Median CRP was 4.10mg/L (q25-q75: 1.67-10) and mean Kt/V was 1.48±0.308. Kt/V was lower in the patients included in the high inflammation group (P=.01). In the multivariate logistic regression, the “high” levels of CRP were directly correlated with the Log neutrophil-lymphocyte ratio (P<.001) and inversely proportional with serum albumin values (P=.014), Kt/V (P=.037) and serum iron (P<.001).Conclusion : The poorer adequacy in terms of dialysis doses (lower Kt/V values) may contribute to a higher degree of inflammation in chronic hemodialysis patients. (AU)

The impact of the correction of hyponatremia during hospital admission on the prognosis of SARS-CoV-2 infection. / Impacto de la corrección temprana de la hiponatremia en el pronóstico de la infección del síndrome respiratorio agudo grave del coronavirus 2 (SARS-CoV-2).

INTRODUCTION: SARS-CoV-2 infection is frequently associated with hyponatremia (plasma sodium<135mmol/L), being associated with a worse prognosis. The incidence of hyponatremia is estimated to be 20-37% according to the series, but there are no data on the prognosis after correction of hyponatremia. Therefore, our objectives were: to analyze the incidence and severity of hyponatremia at hospital admission, and to determine the association of this hyponatremia with the prognosis of COVID-19. MATERIAL AND METHOD: Observational and retrospective cohort study. Patients who were admitted with a diagnosis of COVID-19 infection and hyponatremia, in the period March-May 2020, were included. We recorded epidemiological, demographic, clinical, biochemical, and radiological variables of SARS-CoV-2 infection and hyponatremia at the time of diagnosis and during hospitalization. The clinical follow-up ranged from admission to death or discharge. RESULTS: 91 patients (21.8%) of the 414 admitted for SARS-CoV-2 infection presented hyponatremia (81.32% mild hyponatremia, 9.89% moderate and 8.79% severe). The absence of correction of hyponatremia 72-96h after hospital admission was associated with higher mortality in patients with COVID-19 (Odds Ratio .165; 95% confidence interval: .018-.686; P=.011). 19 patients (20.9%) died. An increase in mortality was observed in patients with severe hyponatremia compared with moderate and mild hyponatremia during hospital admission (37.5% versus 11.1% versus 8.1%, P=.041). CONCLUSIONS: We conclude that persistence of hyponatremia at 72-96h of hospital admission was associated with higher mortality in patients with SARS-CoV-2.