Akt1 is involved in renal fibrosis and tubular apoptosis in a murine model of acute kidney injury-to-chronic kidney disease transition.

Maladaptive repair after acute kidney injury (AKI) can predispose patients to chronic kidney disease (CKD). However, the molecular mechanism underlying the AKI-to-CKD transition remains unclear. The Akt signaling pathway has been reported to be involved in the pathological processes of both AKI and CKD. In this study, we investigated the role of Akt1 in a murine model of the AKI-to-CKD transition. Wild-type (WT) and Akt1-/- mice were subjected to unilateral ischemia-reperfusion injury (UIRI), with their kidneys harvested after two days and two, four, and six weeks after UIRI. The dynamic changes in tubulointerstitial fibrosis, markers of tubular epithelial-mesenchymal transition (EMT), and tubular apoptosis were investigated. Akt1 of the three Akt isoforms was activated during the AKI-to-CKD transition. After UIRI, tubulointerstitial fibrosis and tubular EMT were significantly increased in WT mice, but were attenuated in Akt1-/- mice. The expression of the transforming growth factor (TGF)-ß1/Smad was increased in both WT and Akt1-/- mice, but was not different between the two groups. The levels of phosphorylated glycogen synthase kinase (GSK)-3ß, Snail, and ß-catenin in the Akt1-/- mice were lower than those in the WT mice. The number of apoptotic tubular cells and the expression of cleaved caspase-3/Bax were both lower in Akt1-/- mice than in WT mice. Genetic deletion of Akt1 was associated with attenuation of tubulointerstitial fibrosis, tubular EMT, and tubular apoptosis during the AKI-to-CKD transition. These findings were associated with TGF-ß1/Akt1/GSK-3ß/(Snail and ß-catenin) signaling independent of TGF-ß1/Smad signaling. Thus, Akt1 signaling could serve as a potential therapeutic target for inhibiting the AKI-to-CKD transition.

Maintenance of the critical care system during the pandemic in non-COVID-19 patients requiring continuous renal replacement therapy: a single center experience.

BACKGROUND: During the COVID-19 pandemic, maintenance of essential healthcare systems became very challenging. We describe the triage system of our institute, and assess the quality of care provided to critically ill non-COVID-19 patients requiring continuous renal replacement therapy (CRRT) during the pandemic. METHODS: We introduced an emergency triage pathway early in the pandemic. We retrospectively reviewed the medical records of patients who received CRRT in our hospital from January 2016 to March 2021. We excluded end-stage kidney disease patients on maintenance dialysis. Patients were stratified as medical and surgical patients. The time from hospital arrival to intensive care unit (ICU) admission, the time from hospital arrival to intervention/operation, and the in-hospital mortality rate were compared before (January 2016 to December 2019) and during (January 2021 to March 2021) the pandemic. RESULTS: The mean number of critically ill patients who received CRRT annually in the surgical department significantly decreased during the pandemic in (2016-2019: 76.5 ± 3.1; 2020: 56; p < 0.010). Age, sex, and the severity of disease at admission did not change, whereas the proportions of medical patients with diabetes (before: 44.4%; after: 56.5; p < 0.005) and cancer (before: 19.4%; after: 32.3%; p < 0.001) increased during the pandemic. The time from hospital arrival to ICU admission and the time from hospital arrival to intervention/operation did not change. During the pandemic, 59.6% of surgical patients received interventions/operations within 6 hours of hospital arrival. In Cox's proportional hazard modeling, the hazard ratio associated with the pandemic was 1.002 (0.778-1.292) for medical patients and 1.178 (0.783-1.772) for surgical patients. CONCLUSION: Our triage system maintained the care required by critically ill non-COVID-19 patients undergoing CRRT at our institution.

Intradialytic Hypotension and Newly Recognized Peripheral Artery Disease in Patients Receiving Hemodialysis.

RATIONALE & OBJECTIVE: Intradialytic hypotension (IDH) may decrease systemic circulation to the legs, exacerbating symptoms of peripheral artery disease (PAD). We sought to evaluate the relationship between IDH and newly recognized lower extremity PAD among hemodialysis patients. STUDY DESIGN: Retrospective cohort study. SETTING & PARTICIPANTS: Linking data from the US Renal Data System to the electronic health records of a large dialysis provider, we identified adult patients (≥18 years of age) with Medicare Parts A and B who initiated dialysis (2006-2011) without previously recognized PAD. EXPOSURE: The time-varying proportion of hemodialysis sessions with IDH defined as the nadir intradialytic systolic blood pressure <90 mm Hg. We categorized the proportion of sessions with IDH within serial 30-day intervals as 0%, >0% to <15%, 15% to <30%, and ≥30%. OUTCOMES: Newly recognized PAD was ascertained using PAD diagnostic and procedure codes for amputation or revascularization, in serial 30-day intervals subsequent to each 30-day exposure interval. ANALYTICAL APPROACH: To account for the competing risks of death and kidney transplantation, we estimated unadjusted and adjusted subdistribution hazard ratios using the Kaplan-Meier multiple imputation method in combination with the extended Cox model to account for IDH as a time-varying exposure. RESULTS: Among 45,591 patients, those with more frequent baseline IDH had a higher prevalence of cardiovascular diseases. During 61,725 person-years of follow-up, 7,886 patients had newly recognized PAD. We found a graded, direct association between IDH and newly recognized PAD. For example, having IDH in ≥30% of dialysis sessions during a given 30-day interval (vs 0%) was associated with a 24% (95% CI, 17%-32%) higher hazard than having newly recognized PAD in the subsequent 30 days. LIMITATIONS: Unmeasured confounding; ascertainment of PAD from claims. CONCLUSIONS: Patients receiving hemodialysis who had more frequent IDH had higher rates of newly recognized PAD. Patients with frequent IDH may warrant careful examination for PAD.

Akt1 is involved in tubular apoptosis and inflammatory response during renal ischemia-reperfusion injury.

Renal ischemia-reperfusion injury (IRI) is one of the major causes of acute kidney injury (AKI). Although Akt is involved in renal IRI, it is unclear as to which Akt isoform plays an important role in renal IRI. In this study, we investigated the role of Akt1 in renal IRI. We subjected the C57BL/6 male mice to unilateral IRI with contralateral nephrectomy. Two days after IRI, IRI-kidneys were harvested. The mice were divided into four groups: wild type (WT) IRI, Akt1-/- IRI, WT sham, and Akt1-/- sham. We found that Akt1, not Akt2 or Akt3, was markedly activated in WT IRI than in WT sham mice. The histologic damage score and serum creatinine level significantly increased in WT IRI mice, the increase being the highest in Akt1-/- IRI mice. The number of TdT-mediated dUTP nick-end labeling (TUNEL)-positive tubular cells and expression of cleaved caspase-3/Bax were higher in Akt1-/- IRI mice than in WT IRI mice. The expression of Bcl-2 was lower in Akt1-/- IRI mice than in WT IRI mice. The expression of tumor necrosis factor-α/interleukin-6/interleukin-1ß and number of F4/80-positive macrophages were markedly higher in Akt1-/- IRI than in WT IRI mice. The expression of phosphorylated nuclear factor-κB p65 was also higher in Akt1-/- IRI mice than in WT IRI mice. Our results show that Akt1 deletion exacerbates kidney damage as it increases tubular apoptosis and inflammatory response during renal IRI. Akt1 could be a potential therapeutic target for developing treatments against IRI-induced AKI.

Fe(II)/Fe(III)-Catalyzed Intramolecular Didehydro-Diels-Alder Reaction of Styrene-ynes.

The intramolecular didehydro-Diels-Alder reaction of styrene-ynes was catalyzed by Fe(II) and Fe(III) to produce various naphthalene derivatives under microwave heating conditions. Mechanistic calculations found that the Fe(II) catalyst activates the styrenyl diene in an inverse-electron-demand Diels-Alder reaction, and the consecutive dehydrogenation reaction can be promoted by either Fe(II)-catalyzed direct dehydrogenation or an Fe(III)-catalyzed rearomatization/dehydrogenation pathway.

Plasma neutrophil gelatinase-associated lipocalin is associated with iron status in anemic patients with pre-dialysis chronic kidney disease.

BACKGROUND: Iron deficiency anemia is common in patients with chronic kidney disease (CKD). Neutrophil gelatinase-associated lipocalin (NGAL), a biomarker of acute kidney injury, is known to be associated with iron metabolism. We investigated whether plasma NGAL level is associated with iron status in pre-dialysis CKD patients with anemia. METHODS: This study included 419 patients who had anemia. The subjects were into categorized into a pre-dialysis group (estimated glomerular filtration rate [eGFR] <60 ml/min/1.73 m2, n = 288) and a non-CKD group (eGFR >60 ml/min/1.73 m2, n = 131). The associations between plasma NGAL and iron status (serum ferritin and transferrin saturation [TSAT]), eGFR, albumin, uric acid, total cholesterol, calcium, phosphate, and C-reactive protein (CRP) were assessed. RESULTS: In non-CKD group, plasma NGAL was not associated with any baseline variables including iron indices (TSAT and serum ferritin). In pre-dialysis group, univariate analysis showed plasma NGAL correlated with eGFR, CRP, TSAT, and serum ferritin. In multivariate analysis, plasma NGAL was independently associated with TSAT. However, serum ferritin lost its association with plasma NGAL. In ROC analysis for identifying iron deficiency, the plasma NGAL (best cut-off value ≤394 ng/ml) was superior to the serum ferritin (suggested cut-off value ≤500 ng/ml) in both sensitivity and specificity. CONCLUSIONS: Plasma NGAL is associated with iron status in anemic patients with pre-dialysis CKD. Further studies are needed to demonstrate the role of plasma NGAL in assessing the iron deficiency and in guiding the iron therapy for pre-dialysis CKD patients.

Long-term outcomes in acute kidney injury patients who underwent continuous renal replacement therapy: a single-center experience.

INTRODUCTION: Acute kidney injury (AKI) requiring continuous renal replacement therapy (CRRT) is the most severe form of AKI associated with poor short- and long-term patient outcomes. The aim of this study was to evaluate the variables associated with long-term patient survival in our clinic. METHODS: This was a single-center retrospective study with AKI survivors who received CRRT from March 2011 to February 2015. During the study period, all consecutive AKI survivors who underwent CRRT were included. Patients on maintenance dialysis prior to CRRT were excluded. Data were collected by reviewing the patients' medical charts. Long-term follow-up data were gathered through February 2018. RESULTS: A total of 430 patients were included, and 62.8% of the patients were male. The mean age of the patients was 63.4 ± 14.6 years. The mean serum creatinine level at the time of CRRT initiation was 3.5 ± 2.5 mg/dL. At the time of discharge, the mean eGFR and serum creatinine levels were 58.4 ± 46.7 and 1.7 ± 1.6 mg/dL, respectively. After 3 years, 44.9% of the patients had survived. When we investigated the factors associated with long-term patient mortality, a longer stay in the ICU [OR 1.034 (1.016-1.053), p < 0.001], a history of cancer [OR 3.830 (1.037-3.308), p = 0.037], a prolonged prothrombin time [OR 1.852 (1.037-3.308), p = 0.037] and a lower eGFR at the time of discharge [OR 0.988 (0.982-0.995), p = 0.001] were independently associated with long-term patient mortality. CONCLUSION: Our study demonstrates that long-term mortality after CRRT is associated with longer ICU stays and lower eGFRs at the time of hospital discharge. Our data imply the importance of renal recovery for long-term survival of AKI patients treated with CRRT.

The two isoforms of matrix metalloproteinase- 2 have distinct renal spatial and temporal distributions in murine models of types 1 and 2 diabetes mellitus.

BACKGROUND: We recently reported on the enhanced tubular expression of two discrete isoforms of the MMP-2 (full length and N-terminal truncated, FL-MMP-2, NTT-MMP-2) in a murine model and human diabetic kidneys. In the present study, we examined in more detail the temporal and spatial distributions of MMP-2 isoform expression in murine models of Type 1 and Type 2 diabetes mellitus. METHODS: Diabetic models were streptozotocin (STZ)-induced diabetes (Type 1 diabetes mellitus) and db/db mice (Type 2 diabetes mellitus). We quantified the abundance of two isoforms of MMP-2 transcripts by qPCR. A spatial distribution of two isoforms of MMP-2 was analyzed semi-quantitatively according to time after injection of STZ and with increasing age of db/db mice. Furthermore, immunohistochemistry for nitrotyrosine was performed to examine a potential association between oxidative stress and MMP-2 isoform expression. RESULTS: Both isoforms of MMP-2 were upregulated in whole kidneys from STZ and db/db mice. In the case of FL-MMP-2, mRNA levels significantly increased at 12 and 24 weeks in STZ mice, while the isoform expression was significantly increased only at 16 weeks, in the db/db mice. FL-MMP-2 protein levels increased in the cortices and outer medullae of both STZ and db/db mice as a function of the duration of diabetes. For NTT-MMP-2, mRNA levels increased earlier at 4 weeks in STZ mice and at 10 weeks of age in db/db mice. The expression of NTT-MMP-2 also increased, primarily in the cortices of STZ and db/db mice, as a function of the duration of diabetes. Quantitatively, these findings were consistent with the qPCR results in the case of NTT-MMP-2, respectively (STZ 24 weeks, 3.24 ± 3.70 fold; 16 weeks db/db, 4.49 ± 0.55 fold). In addition, nitrotyrosine was expressed primarily in cortex as compared to medulla as a function of the duration of diabetes similar to NTT-MMP-2 expression. CONCLUSIONS: Two isoforms of MMP-2 are highly inducible in two diabetic murine models and become more abundant as a function of time. As the expression patterns were not the same in the two isoforms of MMP-2, it is possible that each isoform has a discrete role in the development of diabetic renal injury.

Primary Glomerulonephritis with Unique C4d Deposition and Concurrent Non-infectious Intermediate Uveitis: a Case Report and Literature Review.

C4 glomerulopathy is a recently introduced entity that presents with bright C4d staining and minimal or absent immunoglobulin and C3 staining. We report a case of a 62-year-old man with C4 glomerulonephritis (GN) and uveitis. He presented to the nephrology department with proteinuria and hematuria. The patient also had intermediate uveitis along with proteinuria and hematuria. A kidney biopsy that was performed in light of continuing proteinuria and hematuria showed a focal proliferative, focal sclerotic glomerulopathy pattern on light microscopy, absent staining for immunoglobulin or C3 by immunofluorescence microscopy, with bright staining for C4d on immunohistochemistry, and electron-dense deposits on electron microscopy. Consequently, C4 GN was suggested as the pathologic diagnosis. Although laser microdissection and mass spectrometry for glomerular deposit and pathologic evaluation of the retinal tissue were not performed, this is the first report of C4 GN in Korea and the first case of coexisting C4 GN and uveitis in the English literature.

The role of the specialized team in the operation of continuous renal replacement therapy: a single-center experience.

BACKGROUND: The requirement of continuous renal replacement therapy (CRRT) is increasing with the growing incidence of acute kidney injury (AKI). The decision to initiate CRRT is not difficult if an adequate medical history is obtained. However, the handling and maintenance of CRRT constitute a labor-intensive intervention that requires specialized skills. For these reasons, our center organized a specialized CRRT team in March 2013. The aim of this study is to report on the role of a specialized CRRT team and to evaluate the team's outcome. METHODS: This retrospective single-center study evaluated AKI patients who underwent CRRT in the intensive care unit (ICU) from March 2011 to February 2015. Patients were divided into two groups based on whether they received specialized CRRT team intervention. We collected information on demographic characteristics, laboratory parameters, SOFA score, CRRT initiation time, actual delivered dose and CRRT down-time. In-hospital mortality was defined by medical chart review. Binary logistic regression analysis was used to define factors associated with in-hospital mortality. RESULTS: A total of 1104 patients were included in this study. The mean patient age was 63.85 ± 14.39 years old, and 62.8% of the patients were male. After the specialized CRRT team intervention, there was a significant reduction in CRRT initiation time (5.30 ± 13.86 vs. 3.60 ± 11.59 days, p = 0.027) and CRRT down-time (1.78 ± 2.23 vs. 1.38 ± 2.08 h/day, p = 0.002). The rate of in-hospital mortality decreased after the specialized CRRT team intervention (57.5 vs. 49.2%, p = 0.007). When the multivariable analysis was adjusted, delayed CRRT initiation (HR 1.054(1.036-1.072), p < 0.001) was a significant factor in predicting in-hospital mortality, along with an increased SOFA score, lower serum albumin and prolonged prothrombin time. CONCLUSIONS: Our study shows that specialized CRRT team intervention reduced CRRT initiation time, down-time and in-hospital mortality. This study could serve as a logical basis for implementing specialized CRRT teams hospital-wide.

RIFLE classification in geriatric patients with acute kidney injury in the intensive care unit.

BACKGROUND: The RIFLE classification is widely used to assess the severity of acute kidney injury (AKI), but its application to geriatric AKI patients complicated by medical problems has not been reported. METHODS: We investigated 256 geriatric patients (≥65 years old; mean age, 74.4 ± 6.3 years) who developed AKI in the intensive care unit (ICU) according to the RIFLE classification. Etiologic, clinical, and prognostic variables were analyzed. RESULTS: They were categorized into RIFLE-R (n = 53), RIFLE-I (n = 102), and RIFLE-F (n = 101) groups. The overall in-hospital mortality was 39.8 %. There were no significant differences in RIFLE category between survivors and non-survivors. Survivors had significantly less needs for a ventilator and vasopressor, and lower number of failing organs. Survivors had higher systolic blood pressure, hemoglobin level, and serum albumin levels. We performed a logistic regression analysis to identify the independent predictors of in-hospital mortality. In a univariate analysis, hypertension, chronic kidney disease, RIFLE classification, number of failing organs, need for a ventilator and vasopressor, systolic blood pressure, hemoglobin level, and serum albumin levels were identified as prognostic factors of in-hospital mortality. However, in a multivariate analysis, hypertension, chronic kidney disease, number of failing organs, and serum albumin levels were independent risk factors, with no significant difference for in-hospital mortality with the RIFLE classification. CONCLUSION: The RIFLE classification might not be associated with mortality in geriatric AKI patients in the ICU. In geriatric patients with AKI, various factors besides severity of AKI should be considered to predict mortality.

Extracellular volume expansion and the preservation of residual renal function in Korean peritoneal dialysis patients: a long-term follow up study.

INTRODUCTION: In chronic peritoneal dialysis patients, preservation of residual renal function (RRF) is a major determinant of patient survival, and maintaining sufficient intravascular volume has been hypothesized to be beneficial for the preservation of RRF. The present study aimed to test this hypothesis using multifrequency bioimpedence analyzer (MFBIA), in Korean peritoneal dialysis patients. METHODS: A total of 129 patients were enrolled in this study. The baseline MFBIA was checked, and the patients were divided into the following two groups: group 1, extracellular water per total body water (ECW/TBW) < median, group 2, ECW/TBW > median. We followed up the patients, and then we analyzed the changes in the urine output (UO) and the solute clearance (weekly uKt/V) in each group. Data associated with patient and technical survivor were collected by medical chart review. The volume measurement was made using Inbody S20 equipment (Biospace, Seoul, Korea). We excluded the anuric patients at baseline. RESULT: The median value of ECW/TBW was 0.396. The mean patient age was 49.74 ± 10.01 years, and 62.1 % of the patients were male; most of the patients were on continuous ambulatory peritoneal dialysis (89.1 %). The mean dialysis vintage was 26.20 ± 28.71 months. All of the patients were prescribed hypertensive medication, and 48.5 % of the patients had diabetes. After 25.47 ± 6.86 months of follow up, ΔUO and Δweekly Kt/V were not significantly different in the two groups as follows: ΔUO (-236.07 ± 185.15 in group 1 vs -212.21 ± 381.14 in group 2, p = 0.756); Δ weekly Kt/v (-0.23 ± 0.43 in group 1 vs -0.29 ± 0.49 in group 2, p = 0.461). The patient and technical survivor rate was inferior in the group 2, and in the multivariable analysis, initial hypervolemia was an independent factor that predicts both of the patient mortality [HR 1.001 (1.001-1.086), p = 0.047] and the technical failure [HR 1.024 (1.001-1.048), p = 0.042]. CONCLUSIONS: Extracellular volume expansion, measured by MFBIA, does not help preserve residual renal function, and is harmful for the technical and patient survival in Korean peritoneal dialysis patients.

The bacterial colonization in tunneled cuffed dialysis catheter and its effects on residual renal function in incident hemodialysis patients.

BACKGROUND: The bacterial colonization of hemodialysis catheter occurs frequently and reaches to the catheter-related bloodstream infections (CRBSIs). We hypothesized bacterial colonization promotes inflammation and that might be associated with renal outcome. The aim of this study was to investigate the colonization status for tunneled cuffed dialysis catheter (TCC) and the factors for contributing to the catheter colonization and explore whether bacterial colonization would be related with declining of residual renal function (RRF). METHODS: 115 patients who received TCC removal operation and underwent catheter tip culture from January 2005 to June 2014 were enrolled. The follow-up data such as urine output (UO), time to anuria and patients' survival were collected from the patients or their family members by telephone in June, 2014. RESULTS: There were nineteen patients (16.5 %, 19/115) with positive tip culture (colonization group). In the analysis of demographic and biochemical parameters, there were no significant differences between both groups. Fifty of all the subjects responded to the telephone survey and ten patients (20.0 %, 10/50) belonged to colonization group. The monthly decreasing rate of UO was significantly more rapid in colonization group (p = 0.001). The survival analysis showed that colonization group had worse estimated anuria-free survival than non-colonization group (p < 0.001). In multivariate cox regression, bacterial colonization of TCC was an independent factor influencing the loss of RRF (HR 4.29, 95 % CI: 1.905-9.683, p ≤ 0.001). CONCLUSIONS: Bacterial colonization of TCC was associated with rapid loss of RRF.

Cardiac valve calcification is associated with presence and severity of coronary artery disease in patients with pre-dialysis chronic kidney disease.

BACKGROUND: Cardiac valve calcification is common in chronic kidney disease (CKD) patients. Coronary artery disease (CAD) is the one of major causes for increased cardiovascular mortality in CKD patients. We hypothesized that cardiac valve calcification is associated with the presence and the severity of CAD in pre-dialysis CKD patients. METHODS: This study included 1166 patients who underwent transthoracic echocardiography for assessment of cardiac valve calcification and coronary angiography for assessment of CAD. The patients were divided into two groups according to estimated glomerular filtration rate (eGFR): pre-dialysis CKD group (n = 215, eGFR < 60 ml/min/1.73 m(2)) and non-CKD group (n = 951, eGFR ≥ 60 ml/min/1.73 m(2)). RESULTS: In the pre-dialysis CKD group, subjects with aortic valve calcification (AVC), mitral valve calcification (MVC), and at least one valve calcification had more severe CAD compared with those without AVC, MVC, and any valve calcification. Multivariate analysis showed that pre-dialysis CKD patients who had AVC, MVC, and at least one valve calcification were 3.02 times (P = 0.033), 3.73 times (P = 0.029), and 3.31 times (P = 0.012) more likely to have CAD compared with those without AVC, MVC, and any valve calcification, respectively. However, in the non-CKD group, there was no association between cardiac valve calcification and the severity/presence of CAD. CONCLUSIONS: Cardiac valve calcification is associated with the presence and severity of CAD in pre-dialysis CKD. Assessment of cardiac valve calcification by means of transthoracic echocardiography could be a valuable non-invasive method for CAD risk stratification in pre-dialysis CKD patients.

Glycated albumin is a more accurate glycaemic indicator than haemoglobin A1c in diabetic patients with pre-dialysis chronic kidney disease.

AIM: Glycated albumin (GA) has been reported to be a more reliable glycaemic indicator than haemoglobin A1c (HbA1c ) in patients with diabetes on dialysis. However, the significance of these assays has been less evaluated in patients with diabetes and pre-dialysis chronic kidney disease (CKD). METHODS: GA, HbA1c and fasting serum glucose were measured simultaneously in 146 patients with diabetes. Based on estimated glomerular filtration rate (eGFR), the subjects were categorized into a pre-dialysis CKD group (eGFR < 60 mL/min per 1.73 m2 , n = 97) and a non-CKD group (eGFR ≥ 60 mL/min per 1.73 m2 , n = 49). RESULTS: The glucose/HbA1c and GA/HbA1c ratios were significantly higher in the CKD group than those in the non-CKD group. The glucose/GA ratio did not differ significantly between the two groups. In the pre-dialysis CKD group, eGFR was negatively correlated with the glucose/HbA1c ratio (r = -0.343, P = 0.001) and the GA/HbA1c ratio (r = -0.499, P < 0.001). However, no significant correlation was detected between eGFR and the glucose/GA ratio. In the non-CKD group, eGFR was not correlated with the glucose/HbA1c ratio, the glucose/GA ratio, or the GA/HbA1c ratio. A multivariate regression analysis showed that eGFR had a significant impact on HbA1c but no effect on GA in the pre-dialysis CKD group (ß = 0.210, P = 0.005). In the non-CKD group, eGFR did not affect HbA1c or GA. CONCLUSION: Our results show that HbA1c significantly underestimated glycaemic control, whereas GA more accurately reflected glycaemic control in diabetic patients with pre-dialysis CKD.

Pyeloduodenal fistula successfully treated by endoscopic ligation without surgical nephrectomy: case report.

A 74-yr-old woman presented with fever and abdominal discomfort. She was in a septic condition caused by urinary tract infection. Her computed tomogram of the abdomen revealed features of hydronephrosis with ureteral stones in both kidneys. During percutaneous nephrostomies, right pyeloduodenal fistula (PDF) was diagnosed. Elective surgery was originally planned but the patient was in a poor condition to undergo surgery. Instead, 2 times endoscopic clipping and ligation by endoloop were applied with parenteral antibiotics for the fistula lesion. On admission day 30, she was discharged from the hospital after confirmation of no more contrast leakage on fistulography. We reviewed the literature and discuss the etiologies, clinical presentations, diagnosis, and treatment of PDF.

Medium cut-off dialyzer improves reduction ratios of large middle molecules associated with vascular calcification.

Background: We aimed to investigate the change in the large middle molecule (>15 kDa) removal rate, which is associated with vascular calcification, when using a medium cut-off (MCO) dialyzer compared to a high-flux (HF) dialyzer. Methods: Twenty patients with clinically stable maintenance hemodialysis were investigated over a 15-week study period. Dialyzer efficacies were evaluated during the last midweek hemodialysis treatment for each consecutive dialyzer membrane use: 1st HF, MCO, and 2nd HF dialyzer; 5 weeks each period. Changes in α1-microglobulin (33 kDa) during a dialysis session were analyzed to assess the efficacy of the MCO dialyzer as a reference. The levels and reduction ratios of fibroblast growth factor 23 (FGF23, 32 kDa), osteoprotegerin (OPG, 60 kDa), and sclerostin (22 kDa) were analyzed. Large middle molecules were measured using an enzyme-linked immunosorbent assay. Results: Serum hemoglobin, phosphorus, and corrected calcium levels were not significantly different for each dialyzer period. Total protein and albumin values during the MCO dialyzer period did not decrease compared with the HF dialyzer period. The reduction ratio of α1-microglobulin was significantly higher in the MCO dialyzer than in the HF dialyzer (p < 0.001). The reduction ratios of FGF23 (p < 0.001), OPG (p < 0.001), and sclerostin (p < 0.001) were significantly higher in the MCO dialyzer than those in the HF dialyzer. Conclusion: The reduction rate of large middle molecules related to vascular calcification, such as FGF23, OPG, and sclerostin, was significantly higher when using the MCO dialyzer than the HF dialyzer.

Differences in the incidence, characteristics, and outcomes of patients with acute kidney injury in the medical and surgical intensive care units.

Background: Though acute kidney injury (AKI) is a prevalent complication in critically ill patients, knowledge on the epidemiological differences and clinical characteristics of patients with AKI admitted to medical and surgical intensive care units (ICUs) remains limited. Methods: Electronic medical records of patients in ICUs in Pusan National University Hospital and Pusan National University Hospital Yangsan, from January 2011 to December 2020, were retrospectively analyzed. Different characteristics of AKI between patients were analyzed. The contribution of AKI to the in-hospital mortality rate was assessed using a Cox proportional hazards model. Results: A total of 7,150 patients were included in this study. AKI was more frequent in medical (48.7%) than in surgical patients (28.1%), with the severity of AKI higher in medical patients. In surgical patients, hospital-acquired AKI was more frequent (51% vs. 49%), whereas community-acquired AKI was more common in medical patients (58.5% vs. 41.5%). 16.9% and 5.9% of medical and surgical patients died in the hospital, respectively. AKI affected patient groups to different degrees. In surgical patients, AKI patients had 4.778 (3.577, 6.382, p < 0.001) folds higher risk of mortality than non-AKI patients whereas in medical AKI patients, it was 1.239 (1.051, 1.461, p = 0.011). Conclusion: While the prevalence of AKI itself is higher in medical patients, the impact of AKI on mortality was stronger in surgical patients compared to medical patients. This suggests that more attention is needed for perioperative patients to prevent and manage AKI.

The role of nafamostat mesylate anticoagulation in continuous kidney replacement therapy for critically ill patients with bleeding tendencies: a retrospective study on patient outcomes and safety.

Background: Continuous kidney replacement therapy (CKRT) is crucial in the management of acute kidney injury in intensive care units (ICUs). Nonetheless, the optimal anticoagulation strategy for patients with bleeding tendencies remains debated. This study aimed to evaluate patient outcomes and safety of nafamostat mesylate (NM) compared with no anticoagulation (NA) in critically ill patients with bleeding tendencies who were undergoing CKRT. Methods: This retrospective study enrolled 2,313 patients who underwent CKRT between March 2013 and December 2022 at the third affiliated hospital in South Korea. After applying the exclusion criteria, 490 patients were included in the final analysis, with 245 patients in the NM and NA groups each, following 1:1 propensity score matching. Subsequently, in-hospital mortality, incidence of bleeding complications, agranulocytosis, hyperkalemia, and length of hospital stay were assessed. Results: No significant differences were observed between the groups regarding the lengths of hospital and ICU stays or the incidence of agranulocytosis and hyperkalemia. The NM group showed a smaller decrease in hemoglobin levels during CKRT (-1.90 g/dL vs. -2.39 g/dL) and less need for blood product transfusions than the NA group. Furthermore, the NM group exhibited a survival benefit in patients who required transfusion of all three blood products. Conclusion: NM is an effective and safe anticoagulant for CKRT in critically ill patients, especially those requiring transfusion of all three blood products. Although these findings are promising, further multicenter studies are needed to validate them and explore the mechanisms underlying the observed benefits.

The association between transferrin saturation and all-cause mortality in chronic kidney disease: findings from Korean Cohort Study for Outcome in Patients with Chronic Kidney Disease.

Background: Transferrin saturation (TSAT) has been used as an indicator of iron deficiency. However, there is no consensus regarding its optimal range for patient with chronic kidney disease (CKD). We aimed to analyze the effect of TSAT on the prognosis of patients with non-dialysis CKD (NDCKD). Methods: From 2011 to 2016, 2157 NDCKD patients with baseline TSAT measurements were followed for 10 years. Patients were divided into three groups based on baseline TSAT values: <25%, ≥25% and <45%, and ≥45%. All-cause mortality and 4-point major adverse cardiovascular events (MACE) were analyzed using multivariable Cox regression analysis. Other iron biomarkers and mortality were also analyzed. Results: During a mean follow-up of 7.1 ± 2.9 years, 182 of a total of 2,157 patients (8.4%) died. Compared with the TSAT ≥25% and <45% group, the TSAT <25% group showed significantly increased all-cause mortality (hazard ratio [HR], 1.44; 95% confidence interval (CI), 1.02-2.03; p = 0.04). The occurrence of 4-point MACE was significantly increased in univariable analysis in the TSAT <25% group (HR, 1.48; 95% CI, 1.02-2.15; p = 0.04), but it was not significant in the multivariable analysis (HR, 1.38; 95% CI, 0.89-2.15; p = 0.15). Tertile comparisons of the iron-to-log-ferritin ratio showed increased mortality in the first tertile group. Conclusion: TSAT <25% is an independent risk factor for all-cause mortality in patients with NDCKD and care should be taken to prevent TSAT values of <25%. Other indicators, such as serum iron and iron-to-log-ferritin ratio, may also be used to assess iron deficiency.