Metformin induces lactate accumulation and accelerates renal cyst progression in Pkd1-deficient mice.

Metabolic reprogramming is a potential treatment strategy for autosomal dominant polycystic kidney disease (ADPKD). Metformin has been shown to inhibit the early stages of cyst formation in animal models. However, metformin can lead to lactic acidosis in diabetic patients with advanced chronic kidney disease, and its efficacy in ADPKD is still not fully understood. Here, we investigated the effect of metformin in an established hypomorphic mouse model of PKD that presents stable and heritable knockdown of Pkd1. The Pkd1 miRNA transgenic mice of both genders were randomized to receive metformin or saline injections. Metformin was administrated through daily intraperitoneal injection from postnatal day 35 for 4 weeks. Unexpectedly, metformin treatment at a concentration of 150 mg/kg increased disease severity, including kidney-to-body weight ratio, cystic index and plasma BUN levels, and was associated with increased renal tubular cell proliferation and plasma lactate levels. Functional enrichment analysis for cDNA microarrays from kidney samples revealed significant enrichment of several pro-proliferative pathways including ß-catenin, hypoxia-inducible factor-1α, protein kinase Cα and Notch signaling pathways in the metformin-treated mutant mice. The plasma metformin concentrations were still within the recommended therapeutic range for type 2 diabetic patients. Short-term metformin treatment in a second Pkd1 hypomorphic model (Pkd1RC/RC) was however neutral. These results demonstrate that metformin may exacerbate late-stage cyst growth associated with the activation of lactate-related signaling pathways in Pkd1 deficiency. Our findings indicate that using metformin in the later stage of ADPKD might accelerate disease progression and call for the cautious use of metformin in these patients.

Transcriptome landscape reveals the chronic inflammatory response in kidneys affected by the combinatory effect of leptospirosis and nephrotoxic injury.

Leptospirosis can cause chronic kidney damage, putting patients at risk of additional kidney injury due to other factors that can lead to renal failure. To understand the combined effect, the transcriptome profiles of kidneys of mice with adenine-induced and chronically Leptospira-infected kidneys were analysed. Chronic inflammation and T-helper 17 immune responses were activated and a high-level expression of Indoleamine 2,3-dioxygenase 1 protein was found. The results indicate that the combination may predispose patients to chronic inflammation, kidney function disruption, and symptoms seen in progressive chronic kidney disease (CKD). Furthermore, immunometabolic regulation may contribute to renal injury caused by chronic leptospirosis with secondary nephrotoxic injury. This study identified several significantly disrupted genes that could serve as potential targets for the diagnosis or treatment of CKD. Our work provides insight into the combined effect of leptospirosis and secondary kidney damage and the molecular basis for rapid progression of CKD.

Prevention and management of cytomegalovirus infection and disease in kidney transplant: A consensus statement of the Transplantation Society of Taiwan.

Kidney transplant recipients have an increased risk of cytomegalovirus (CMV) infection and disease. A strategy for mitigating the risk of CMV infection in kidney transplant recipients has not yet been established in Taiwan. The Transplantation Society of Taiwan aimed to develop a consensus by expert opinion on the prevention and management of CMV infection. Based on the results of Consensus Conference, we suggested low-dose valganciclovir prophylaxis (450 mg once daily) for kidney transplant recipients. The prophylaxis duration was ≥6 months for high-risk (D+/R-) patients and 3 months for moderate-risk (R+) patients. Even for low-risk (D-/R-) patients, prophylaxis for at least 3 months is recommended because of the high seroprevalence of CMV in Taiwan. CMV prophylaxis was suggested after anti-thymocyte globulin treatment but not after methylprednisolone pulse therapy. Routine surveillance after prophylaxis, secondary prophylaxis after CMV disease treatment, and mTOR inhibitors for primary CMV prophylaxis were not recommended. Letermovir and marabavir are emerging CMV agents used for prophylaxis and refractory CMV disease. CMV immunoglobulins have been used to treat refractory CMV disease in Taiwan. We hope this consensus will help professionals manage patients with CMV in Taiwan to improve the quality of care.

Characteristics of and Outcomes After Dialysis-Treated Acute Kidney Injury, 2009-2018: A Taiwanese Multicenter Study.

RATIONALE & OBJECTIVE: Dialysis-treated acute kidney injury (AKI) is increasingly common in intensive care units (ICUs) and is associated with poor outcomes. Few studies have explored the temporal trends in severity of acute illness at dialysis initiation, indications for dialysis, and their association with patient outcomes. STUDY DESIGN: Multicenter retrospective cohort study. SETTING & PARTICIPANTS: 9,535 adult patients admitted to the ICU who received their first dialysis treatment from Chang Gung Memorial Hospital system in Taiwan from 2009 through 2018. EXPOSURE: Calendar year. OUTCOMES: ICU mortality and dialysis treatment at discharge among hospital survivors. ANALYTICAL APPROACH: The temporal trends during the study period were investigated using test statistics suited for continuous or categorical data. The association between the study year and the risk of mortality was analyzed using multivariable Cox regression with adjustment for relevant clinical variables, including the severity of acute illness, defined by Sequential Organ Failure Assessment (SOFA) score. RESULTS: The mean SOFA score at dialysis initiation decreased slightly from 14.0 in 2009 to 13.6 in 2018. There was no significant trend in the number of indications for dialysis initiation that were fulfilled over time. Observed ICU mortality decreased over time, and the curve appeared to be reverse J-shaped, with a substantial decrease from 56.1% in 2009 to 46.3% in 2015 and a slight increase afterward. The risk of mortality was significantly reduced from 2013 to 2018 compared with 2009 in adjusted models. The decreasing trend in ICU mortality over time remained significant. There was an increase in dialysis treatment at discharge among survivors, mainly in patients with estimated glomerular filtration rate<60mL/min/1.73m2, from 36.8% in 2009 to 43.9% in 2018. LIMITATIONS: Residual confounding from unmeasured factors over time such as severity of comorbidities, detailed medication interventions, and delivered dialysis dose. CONCLUSIONS: We observed reductions in mortality among ICU patients with dialysis-treated acute kidney injury between 2009 and 2018, even after adjusting for dialysis indication and severity of illness at dialysis initiation. However, dialysis treatment at discharge among survivors has increased over time, mainly in patients with preexisting kidney disease. PLAIN-LANGUAGE SUMMARY: The current medical management of severe acute kidney injury (AKI) is primarily limited to supportive care and kidney replacement therapy if indicated, leading to perceptions that outcomes among intensive care unit (ICU) patients with dialysis-treated AKI have not improved. In this multicenter retrospective study of ICU patients with dialysis-treated AKI between 2009 and 2018 in Taiwan, patient mortality decreased over time despite increasing comorbidities. Moreover, the decreasing linear trends remained significant even when considering severity of acute illness at dialysis initiation, which was based on physiologic and laboratory measurements seldom evaluated in previous studies. Further research should explore the basis for these improvements.

Tumor necrosis factor-alpha blockade suppresses BK polyomavirus replication.

PURPOSE: BK Polyomavirus (BKPyV) infection manifests as renal inflammation and can cause kidney damage. Tumor necrosis factor-α (TNF-α) is increased in renal inflammation and injury. The aim of this study was to investigate the effect of TNF-α blockade on BKPyV infection. METHODS: Urine specimens from 22 patients with BKPyV-associated nephropathy (BKPyVN) and 35 non-BKPyVN kidney transplant recipients were analyzed. RESULTS: We demonstrated increased urinary levels of TNF-α and its receptors, TNFR1 and TNFR2, in BKPyVN patients. Treating BKPyV-infected human proximal tubular cells (HRPTECs) with TNF-α stimulated the expression of large T antigen and viral capsid protein-1 mRNA and proteins and BKPyV promoter activity. Knockdown of TNFR1 or TNFR2 expression caused a reduction in TNF-α-stimulated viral replication. NF-κB activation induced by overexpression of constitutively active IKK2 significantly increased viral replication and the activity of the BKPyV promoter containing an NF-κB binding site. The addition of a NF-κB inhibitor on BKPyV-infected cells suppressed viral replication. Blockade of TNF-α functionality by etanercept reduced BKPyV-stimulated expression of TNF-α, interleukin-1ß (IL-1ß), IL-6 and IL-8 and suppressed TNF-α-stimulated viral replication. In cultured HRPTECs and THP-1 cells, BKPyV infection led to increased expression of TNF-α, interleukin-1 ß (IL-1ß), IL-6 and TNFR1 and TNFR2 but the stimulated magnitude was far less than that induced by poly(I:C). This may suggest that BKPyV-mediated autocrine effect is not a major source of TNFα. CONCLUSION: TNF-α stimulates BKPyV replication and inhibition of its signal cascade or functionality attenuates its stimulatory effect. Our study provides a therapeutic anti-BKPyV target.

Tuberculous peritonitis in patients on peritoneal dialysis: a 35-year experience from a large medical center in Northern Taiwan.

INTRODUCTION: Tuberculous peritonitis (TBP) is a rare but fatal complication in patients on peritoneal dialysis (PD). In this study, we aimed to determine the demographic features, clinical features, laboratory parameters, and clinical outcomes of PD patients with TBP and to clarify possible risk factors for mortality. MATERIALS AND METHODS: We retrospectively reviewed 2084 PD patients from January 1985 to December 2019. The diagnosis of TBP was established by positive peritoneal fluid culture for Mycobacterium tuberculosis. RESULTS: 18 patients were diagnosed with TBP. The incidence was 2.029 episodes per 1000 patient-years. The most common symptom was fever (94.4%), followed by cloudy effluent (83.3%) and abdominal pain (83.3%). The average peritoneal dialysis effluent (PDE) white blood cell (WBC) count was 172.7 cells/µL. Nine patients (50%) had WBC counts lower than 100 cells/µL and 13 patients (72.2%) had neutrophilic predominant WBC counts. Acid fast stain (AFS) was positive in 7 patients (38.9%). Only 2 patients (11.1%) continued with PD after TB infection, while 10 patients (55.6%) changed to hemodialysis. Seven patients (38.9%) died within 1 year. Significant differences were observed in sex (p = 0.040), the presence of diabetes mellitus (p = 0.024), and PD catheter removal (p < 0.001) between TBP patients with and without mortality. However, none of them was a significant factor for 1-year mortality in multivariate Cox regression model. CONCLUSION: Physicians should pay attention to the unusual presentations of peritonitis, especially if symptoms include fever or an initial low PDE WBC count. Catheter removal is not mandatory if early diagnosis and appropriate therapy are available.

Clinical Benefits of Laparoscopic Adhesiolysis during Peritoneal Dialysis Catheter Insertion: A Single-Center Experience.

Background and Objectives: In peritoneal dialysis (PD) therapy, intra-abdominal adhesions (IAAs) can cause catheter insertion failure, poor dialysis function, and decreased PD adequacy. Unfortunately, IAAs are not readily visible to currently available imaging methods. The laparoscopic approach for inserting PD catheters enables direct visualization of IAAs and simultaneously performs adhesiolysis. However, a limited number of studies have investigated the benefit/risk profile of laparoscopic adhesiolysis in patients receiving PD catheter placement. This retrospective study aimed to address this issue. Materials and Methods: This study enrolled 440 patients who received laparoscopic PD catheter insertion at our hospital between January 2013 and May 2020. Adhesiolysis was performed in all cases with IAA identified via laparoscopy. We retrospectively reviewed data, including clinical characteristics, operative details, and PD-related clinical outcomes. Results: These patients were classified into the adhesiolysis group (n = 47) and the non-IAA group (n = 393). The clinical characteristics and operative details had no remarkable between-group differences, except the percentage of prior abdominal operation history was higher and the median operative time was longer in the adhesiolysis group. PD-related clinical outcomes, including incidence rate of mechanical obstruction, PD adequacy (Kt/V urea and weekly creatinine clearance), and overall catheter survival, were all comparable between the adhesiolysis and non-IAA groups. None of the patients in the adhesiolysis group suffered adhesiolysis-related complications. Conclusions: Laparoscopic adhesiolysis in patients with IAA confers clinical benefits in achieving PD-related outcomes comparable to those without IAA. It is a safe and reasonable approach. Our findings provide new evidence to support the benefits of this laparoscopic approach, especially in patients with a risk of IAAs.

Ultrafiltration in patients on automated peritoneal dialysis with Homechoice Claria connected to Sharesource: A pilot study.

INTRODUCTION: Fluid overload is an unavoidable problem in patients on peritoneal dialysis (PD) and is associated with poor outcomes. The aim of our study was to estimate ultrafiltration (UF) under different dextrose concentrations (DCs) and four peritoneal transport levels. MATERIALS AND METHODS: 70 patients, with a total of 1,848 daily treatment records and 8,266 single dwells on automated PD (APD) through Homechoice Claria with Sharesource were followed in October 2020 and categorized into two groups according to the DC (D1.5% and D2.5% groups). Baseline characteristics, peritoneal membrane characteristics, and daily PD treatment records from Sharesource were obtained. We compared UF under the different conditions. RESULTS: The mean night UF per cycle, the mean night UF corrected by fill volume (FV) per cycle, and the mean night UF corrected by FV and dwelling time (DT) per cycle were all significantly higher in the D2.5% group than in the D1.5% group (95.8 vs. 220.3 mL, 5.5 vs. 12.0%, and 5.0 vs. 11.6 0/000/minutes, all p < 0.001). However, there was no significant difference among the four transport categories in any group. CONCLUSION: This retrospective study presents precise UF measurements with two solutions at different DCs and four peritoneal transport levels. With a 2-L indwell (DT ranging from ~ 1 to 3 hours), the mean net UF rate was 1.0 mL/min in the D1.5% group and 2.3 mL/min in the D2.5% group.

Effectiveness of end-stage renal disease communication skills training for healthcare personnel: a single-center, single-blind, randomized study.

BACKGROUND: Given that the consequences of treatment decisions for end-stage renal disease (ESRD) patients are long-term and significant, good communication skills are indispensable for health care personnel (HCP) working in nephrology. However, HCP have busy schedules that make participation in face-to-face courses difficult. Thus, online curricula are a rising trend in medical education. This study aims to examine the effectiveness of online ESRD communication skills training (CST) concerning the truth-telling confidence and shared decision-making (SDM) ability of HCP. METHODS: For this single-center, single-blind study, 91 participants (nephrologists and nephrology nurses) were randomly assigned to two groups, the intervention group (IG) (n = 45) or the control group (CG) (n = 46), with the IG participating in ESRD CST and the CG receiving regular in-service training. Truth-telling confidence and SDM ability were measured before (T0), 2 weeks after (T1), and 4 weeks after (T2) the intervention. Group differences over the study period were analyzed by generalized estimating equations. RESULTS: IG participants exhibited significantly higher truth-telling confidence at T1 than did CG participants (t = 2.833, P = .006, Cohen's d = 0.59), while there were no significant intergroup differences in the confidence levels of participants in the two groups at T0 and T2. Concerning SDM ability, there were no significant intergroup differences at any of the three time points. However, IG participants had high levels of satisfaction (n = 43, 95%) and were willing to recommend ESRD CST to others (n = 41, 91.1%). CONCLUSIONS: ESRD CST enhanced short-term truth-telling confidence, though it is unclear whether this was due to CST content or the online delivery. However, during pandemics, when face-to-face training is unsuitable, online CST is an indispensable tool. Future CST intervention studies should carefully design interactive modules and control for method of instruction.

Effects of Suramin on Polycystic Kidney Disease in a Mouse Model of Polycystin-1 Deficiency.

The aberrant activation of the purinergic signaling pathway has been shown to promote cyst growth and fluid secretion in autosomal dominant polycystic kidney disease (ADPKD). Suramin is an anti-parasitic drug that has strong anti-purinergic properties. Whether suramin could have a therapeutic effect on ADPKD has not been fully investigated. We examined the effect of suramin on cyst progression in a Pkd1 microRNAs transgenic mouse model that presented stable Pkd1 knockdown and moderate disease progression. The Pkd1-deficient mice were treated with suramin (60 mg/kg) by intraperitoneal injection twice a week from postnatal days 35 to 90. Kidney-to-body weight ratios, cyst indices, and blood urea nitrogen (BUN) levels were measured. Cell proliferation and macrophage infiltration were determined by immunohistochemistry. The suramin-treated group had significantly lower renal cyst densities, cell proliferation, and macrophage infiltration compared with saline-treated controls. Suramin significantly inhibited ERK phosphorylation and the expression of Il1b, Il6, Nlrp3, Tgfb, Fn1, P2rx7, and P2ry2 mRNAs in the kidneys. However, BUN levels remained high despite the reduction in cyst growth. Furthermore, plasma cystatin C and neutrophil gelatinase-associated lipocalin (NGAL) levels were significantly higher in the suramin-treated group compared with the control group. Periodic acid-Schiff staining revealed degenerative changes and epithelial cell vacuolation in the non-cystic renal tubules, which indicated phospholipidosis following suramin treatment. These results suggest that suramin may reduce renal cyst growth and inflammation, but the associated tubular cell injuries could limit its therapeutic potential. Other purinergic receptor antagonists with less nephrotoxicity may deserve further investigation for the treatment of ADPKD.

Transcriptomic signatures of exacerbated progression in leptospirosis subclinical chronic kidney disease with secondary nephrotoxic injury.

High-incidence regions of leptospirosis caused by Leptospira spp. coincide with chronic kidney disease. This study investigated whether asymptomatic leptospirosis is an emerging culprit that predisposes to progressive chronic kidney disease when superimposed on secondary nephrotoxic injury. Kidney histology/function and whole transcriptomic profiles were evaluated for Leptospira-infected C57/BL6 mice with adenine-induced kidney injury. The extent of tubulointerstitial kidney lesions and expression of inflammation/fibrosis genes in infected mice with low-dose (0.1%) adenine, particularly in high-dose (0.2%) adenine-fed superimposed on Leptospira-infected mice, were significantly increased compared with mice following infection or adenine diet alone, and the findings are consistent with renal transcriptome analysis. Pathway enrichment findings showed that integrin-ß- and fibronectin-encoding genes had distinct expression within the integrin-linked kinase-signaling pathway, which were upregulated in 0.2% adenine-fed Leptospira-infected mice but not in 0.2% adenine-fed mice, indicating that background subclinical Leptospiral infection indeed enhanced subsequent secondary nephrotoxic kidney injury and potential pathogenic molecules associated with secondary nephrotoxic leptospirosis. Comparative analysis of gene expression patterns with unilateral ureteric obstruction-induced mouse renal fibrosis and patients with chronic kidney disease showed that differentially expressed orthologous genes such as hemoglobin-α2, PDZ-binding kinase, and DNA topoisomerase II-α were identified in infected mice fed with low-dose and high-dose adenine, respectively, revealing differentially expressed signatures identical to those found in the datasets and may serve as markers of aggravated kidney progression. This study indicates that background subclinical leptospirosis, when subjected to various degrees of subsequent secondary nephrotoxic injury, may predispose to exacerbated fibrosis, mimicking the pathophysiological process of progressive chronic kidney disease.NEW & NOTEWORTHYLeptospira-infected mice followed by secondary nephrotoxic injury exacerbated immune/inflammatory responses and renal fibrosis. Comparison with the murine model revealed candidates involved in the progression of renal fibrosis in chronic kidney disease (CKD). Comparative transcriptome study suggests that secondary nephrotoxic injury in Leptospira-infected mice recapitulates the gene expression signatures found in CKD patients. This study indicates that secondary nephrotoxic injury may exacerbate CKD in chronic Leptospira infection implicating in the progression of CKD of unknown etiology.

Disseminated intravascular coagulation in Stevens-Johnson syndrome and toxic epidermal necrolysis.

BACKGROUND: Patients with Stevens-Johnson syndrome (SJS)/toxic epidermal necrolysis (TEN) have high mortality rates. Disseminated intravascular coagulation has been reported in SJS/TEN patients. The influence of this lethal complication in patients with SJS/TEN is not well known. OBJECTIVE: This study aimed to investigate the risk and outcomes of disseminated intravascular coagulation in patients with SJS/TEN. METHODS: We analyzed the disseminated intravascular coagulation profiles of patients receiving a diagnosis of SJS/TEN between 2010 and 2019. RESULTS: We analyzed 150 patients with SJS/TEN (75 with SJS, 22 with overlapping SJS/TEN, and 53 with TEN) and their complete disseminated intravascular coagulation profiles. Disseminated intravascular coagulation was diagnosed in 32 patients (21.3%), primarily those with TEN. It was significantly associated with systemic complications, including gastrointestinal bleeding, respiratory failure, renal failure, liver failure, infection, and bacteremia. Additionally, SJS/TEN patients with disseminated intravascular coagulation had elevated procalcitonin levels. Among patients with SJS/TEN, disseminated intravascular coagulation was associated with a greater than 10-fold increase in mortality (78.1% vs 7%). LIMITATIONS: The study limitations include small sample size and a single hospital system. CONCLUSION: Disseminated intravascular coagulation is a potential complication of SJS/TEN and associated with higher mortality. Early recognition and appropriate management of this critical complication are important for patients with SJS/TEN.

Crystal structure of Leptospira leucine-rich repeat 20 reveals a novel E-cadherin binding protein to induce NGAL expression in HK2 cells.

Leptospirosis is the most common zoonotic disease caused by pathogenic Leptospira, which is classified into three groups according to virulence. Its pathogenic and intermediate species contain leucine-rich repeat (LRR) proteins that are rarely expressed in non-pathogenic strains. In this study, we presented the crystal structure of LSS_11580 (rLRR20) from pathogenic L. santarosai serovar Shermani. X-ray diffraction at a resolution of 1.99 Šrevealed a horseshoe-shaped structure containing seven α-helices and five ß-sheets. Affinity assays indicated that rLRR20 interacts with E-cadherin on the cell surface. Interestingly, its binds to the extracellular (EC) 1 domain in human epithelial (E)-cadherin, which is responsible for binding to another E-cadherin molecule in neighboring cells. Several charged residues on the concave face of LRR20 were predicted to interact with EC1 domain. In the affinity assays, these charged residues were replaced by alanine, and their affinities to E-cadherin were measured. Three vital residues and mutation variants of LRR20, namely D56A, E59A, and E123A, demonstrated significantly reduced affinity to E-cadherin compared with the control. Besides, we also demonstrated that rLRR20 induced the expression of neutrophil gelatinase-associated lipocalin (NGAL) in HK2 cells. The low ability of the three mutation variants to induce NGAL expression further demonstrates this induction. The present findings indicate that LRR20 from pathogenic Leptospira binds to E-cadherin and interacts with its EC1 domain. In addition, its induction of NGAL expression in HK2 cells is associated with acute kidney injury in human.

TAFRO Syndrome with Renal Thrombotic Microangiopathy: Insights into the Molecular Mechanism and Treatment Opportunities.

TAFRO syndrome is an extremely rare form of idiopathic MCD, characterized by thrombocytopenia, anasarca, fever, reticulin fibrosis on bone marrow biopsy, and organomegaly. Like idiopathic MCD, renal involvement is also a common presentation in patients with TAFRO syndrome. Furthermore, membranoproliferative glomerulonephritis (MPGN)-like injury and thrombotic microangiopathy (TMA) are the most reported histopathologic findings of renal biopsy. Several molecular mechanisms have been previously postulated in order to explain the TAFRO syndrome symptoms, including abnormal production of interleukin-6 (IL-6), vascular endothelial growth factor (VEGF), etc. The role of these cytokines in renal injury, however, is not well understood. The aim of this review article is to summarize the latest knowledge of molecular mechanisms behind the TAFRO syndrome and their potential role in renal damage.

Crosstalk between E-Cadherin/ß-Catenin and NF-κB Signaling Pathways: The Regulation of Host-Pathogen Interaction during Leptospirosis.

Approximately 1 million cases of leptospirosis, an emerging infectious zoonotic disease, are reported each year. Pathogenic Leptospira species express leucine-rich repeat (LRR) proteins that are rarely expressed in non-pathogenic Leptospira species. The LRR domain-containing protein family is vital for the virulence of pathogenic Leptospira species. In this study, the biological mechanisms of an essential LRR domain protein from pathogenic Leptospira were examined. The effects of Leptospira and recombinant LRR20 (rLRR20) on the expression levels of factors involved in signal transduction were examined using microarray, quantitative real-time polymerase chain reaction, and western blotting. The secreted biomarkers were measured using an enzyme-linked immunosorbent assay. rLRR20 colocalized with E-cadherin on the cell surface and activated the downstream transcription factor ß-catenin, which subsequently promoted the expression of MMP7, a kidney injury biomarker. Additionally, MMP7 inhibitors were used to demonstrate that the secreted MMP7 degrades surface E-cadherin. This feedback inhibition mechanism downregulated surface E-cadherin expression and inhibited the colonization of Leptospira. The degradation of surface E-cadherin activated the NF-κB signal transduction pathway. Leptospirosis-associated acute kidney injury is associated with the secretion of NGAL, a downstream upregulated biomarker of the NF-κB signal transduction pathway. A working model was proposed to illustrate the crosstalk between E-cadherin/ß-catenin and NF-κB signal transduction pathways during Leptospira infection. Thus, rLRR20 of Leptospira induces kidney injury in host cells and inhibits the adhesion and invasion of Leptospira through the upregulation of MMP7 and NGAL.

Intravenous iron supplementation does not increase infectious disease risk in hemodialysis patients: a nationwide cohort-based case-crossover study.

BACKGROUND: Studies have reported conflicting findings on the infection risk posed by intravenous iron supplementation among hemodialysis (HD) patients. We used a novel study design to assess associations between intravenous iron and infectious diseases. METHODS: Patients initiating HD between 1998 and 2008 were extracted from Taiwan's National Health Insurance Research Database. Their first infectious disease in the period between 1.5 years after dialysis initiation and 2010 was identified and defined as the index date. Through the case-crossover design, the odds of exposure to intravenous iron within the 1-month period immediately preceding the index date (i.e., the case period) were compared with iron exposure in three different matched control periods for the same enrollee, thus possibly reducing some unmeasured confounders. RESULTS: A total of 1410 patients who met our enrollment criteria were extracted from incident HD patients. The odds of intravenous iron exposure during the case period versus total control periods exhibited no significant difference (odds ratio: 1.000, 95% confidence interval: 0.75-1.33). In subgroup analyses, this association remained nonsignificant across patients with diabetes mellitus, heart failure, chronic lung disease, venous catheter for HD, and higher iron load. CONCLUSIONS: We found that intravenous iron supplementation did not increase short-term infection risk among HD patients.

Analysis of survival after initiation of continuous renal replacement therapy in patients with extracorporeal membrane oxygenation.

BACKGROUND: No study has specifically investigated the duration of continuous renal replacement therapy (CRRT) in patients who experienced acute kidney injury during extracorporeal membrane oxygenation (ECMO) support. However, there are concerns that prolonged CRRT may be futile. METHODS: We conducted a retrospective population-based cohort study using Taiwan National Health Insurance Research Database data collected between January 1, 2007 and December 31, 2013. Patients who received ECMO and CRRT during the study period were included. We divided patients into three groups based on the duration of CRRT received: ≤ 3 days, 4-6 days, and ≥ 7 days. The outcomes were all-cause mortality, end-stage renal disease, ventilator dependency, and readmission rate. RESULTS: There were 247, 134 and 187 patients who survived the hospitalization in the CRRT for ≤3 days, 4-6 days and > 7 days respectively. Survival after discharge did not differ significantly between CRRT for 4-6 days vs. ≤ 3 days (adjusted hazard ratio [aHR] 1.16, 95% confidence interval [CI] 0.85-1.57), between CRRT for > 7 days vs. ≤ 3 days (aHR 1.001, 95% CI 0.73-1.38) and between CRRT for > 7 days vs. 4-6 days (aHR 0.87, 95% CI 0.62-1.22). The patients who received CRRT for ≥7 days had a higher risk of ESRD than did those who received CRRT for ≤3 days (adjusted hazard ratio [aHR] 3.46, 95% confidence interval [CI] 1.47-8.14) and for 4-6 days (aHR 3.10, 95% CI 1.03-9.29). The incidence of ventilator dependence was higher in the patients with CRRT ≥7 days than in those with ≤3 days (aHR 2.45, 95% CI 1.32-4.54). The CRRT ≥7 days group also exhibited a higher readmission rate than did the 4-6 days and ≤ 3 days groups (aHR 1.43, 95% CI 1.04-1.96 and aHR 1.67, 95% CI 1.13-2.47, respectively). CONCLUSIONS: Our study found similar long-term survival but increased ESRD and ventilator dependency among ECMO patients who underwent CRRT for ≥7 days. These results offer reason to be concerned that this aggressive life support may maintain patient survival but do so at the cost of long-term disabilities and a lower quality of life.

Prognostic value of endothelial biomarkers in refractory cardiogenic shock with ECLS: a prospective monocentric study.

BACKGROUND: Extracorporeal membrane oxygenation (ECMO) is often used in critical patients with severe myocardial failure. However, the mortality rate of patients on ECMO is often high. Recent studies have suggested that endothelial activation with subsequent vascular barrier breakdown is a critical pathogenic mechanism of organ damage and is related to the outcome of critical illness. This study aimed to determine whether endothelial biomarkers can be served as prognostic factors for the outcome of patients on ECMO. METHODS: This prospective study enrolled 23 critically ill patients on veno-arterial ECMO in the intensive care units of a tertiary care hospital between March 2014 and February 2015. Serum samples were tested for thrombomodulin, angiopoietin (Ang)-1, Ang-2, and vascular endothelial growth factor (VEGF). Demographic, clinical, and laboratory data were also collected. RESULTS: The overall mortality rate was 56.5%. The combination of Ang-2 at the time of ECMO support (day 0) and VEGF at day 2 had the ability to discriminate mortality (area under receiver operating characteristic curve [AUROC], 0.854; 95% confidence interval: 0.645-0.965). CONCLUSIONS: In this study, we found that the combination of Ang-2 at day 0 and VEGF at day 2 was a modest model for mortality discrimination in this group of patients.

High anti-neutrophil cytoplasmic antibody titers are associated with the requirement of permanent dialysis in patients with myeloperoxidase-ANCA-associated vasculitis.

BACKGROUND/PURPOSE: A reliable noninvasive prognostic factor of ANCA-associated vasculitis (AAV) is still lacking, but little research has focused on the value of MPO-ANCA titers in patients with active vasculitis. This study explored the prognostic significance of MPO-ANCA titer in active AAV patients. METHODS: Ninety-seven inpatients diagnosed with MPO-ANCA associated vasculitis at Linkou Chang Gung Memorial hospital and Keelung Chang Gung Memorial hospital from January 2005 to December 2016 were enrolled. Serum ANCA titers and basic characteristics of these patients at diagnosis were collected completely Medical records since AAV diagnosis were reviewed to evaluate two years renal and patient outcome. RESULTS: The patients were divided into the two groups according to the median ANCA titers, the more than four times of the normal cut-off value group (high titer group) and the less ANCA titer group (low titer group). The high titer group had significant poor initial renal function (eGFR 16.7 vs 40.7 mL/min/1.73 m2, P = 0.006), and significantly lower two-year renal survival (Log rank P < 0.001). Whereas patient survival (Log rank P = 0.894) was not different The Cox regression models revealed that baseline Birmingham Vasculitis Activity Score, eGFR and a 4-fold increase in ANCA titer were associated with the requirement of permanent dialysis. In the subgroup analysis, the ANCA titer was still an important risk factor for renal outcomes (P = 0.036) in patients with better initial renal function (eGFR≧15 mL/min). CONCLUSION: This study demonstrated that higher MPO-ANCA titers at diagnosis was associated with poor initial renal function and 2-year renal outcomes.

Murine Renal Transcriptome Profiles Upon Leptospiral Infection: Implications for Chronic Kidney Diseases.

Background: Leptospirosis caused by pathogenic Leptospira spp leads to kidney damage that may progress to chronic kidney disease. However, how leptospiral infections induced renal damage is unclear. Methods: We apply microarray and next-generation sequencing technologies to investigate the first murine transcriptome-wide, leptospires-mediated changes in renal gene expression to identify biological pathways associated with kidney damage. Results: Leptospiral genes were detected in renal transcriptomes of mice infected with Leptospira interrogans at day 28 postinfection, suggesting colonization of leptospires within the kidney with propensity of chronicity. Comparative differential gene expression and pathway analysis were investigated in renal transcriptomes of mice infected with pathogens and nonpathogens. Pathways analysis showed that Toll-like receptor signaling, complements activation, T-helper 1 type immune response, and T cell-mediated immunity/chemotaxis/proliferation were strongly associated with progressive tubulointerstitial damage caused by pathogenic leptospiral infection. In addition, 26 genes related with complement system, immune function, and cell-cell interactions were found to be significantly up-regulated in the L interrogans-infected renal transcriptome. Conclusions: Our results provided comprehensive knowledge regarding the host transcriptional response to leptospiral infection in murine kidneys, particularly the involvement of cell-to-cell interaction in the immune response. It would provide valuable resources to explore functional studies of chronic renal damage caused by leptospiral infection.