Objective To explore the prevalence and risk factors of exit-site infection (ESI) in elderly peritoneal dialysis (PD) patients. Methods The status of exit-site was evaluated in elderly PD patients (≥60 years) who had catheter insertion in our center between January 1, 2009 and December 31, 2013, with follow-up for 1 year or withdrawing from peritoneal dialysis in this period. The patients were divided into ESI and non-ESI group. The data was collected including demographics, clinical features, and nursing care methods of the exit-site. Results A total of 247 patients were recruited in this study, aged (68.6±6.2) years, among whom there were 132 male (53.4%) and 119 diabetes (48.2%). Median follow-up time was 12.0 months. Thirty-two patients had 34 episodes of ESI with a rate of 82.5 patient-months per episode (0.15 episodes per year). Coagulase-negative Staphylococcus was the main pathogen, accounting for 35.3% of the ESI. No bacterial growth was found in 8.8%. The exit-site nursing care status included that poor compliance of exit-site care 23.5%, poor catheter immobilization 62.3%, history of catheter-pulling injury 9.7%, mechanical stress on exit-site 5.3%, improper frequency of nursing care 29.6%, mupirocin usage 13.8%, patients taking exit-site care 26.7%, exit-site caregiver instability 16.6%. There were no differences in demographic (such as age, gender, primary disease, etc) and laboratory data (hemoglobin, serum albumin, blood potassium, etc) between the ESI and non-ESI groups. Poor compliance with exit-site care (HR=2.352, 95%CI 1.008-5.488, P=0.048), poor catheter immobilization (HR=3.074, 95%CI 1.046-9.035, P=0.041) and exit-site caregiver instability (HR=2.423, 95%CI 1.004-5.845, P=0.049) were significantly correlated with increased risk of ESI. Conclusions The prevalence of ESI in elderly PD patients was 0.15 episodes per year. Educating PD patients to improve the compliance with exit-site care, maintain catheter immobilization and do exit-site care by a stable and trained caregiver may reduce ESI events in elderly PD patients.

Objective To investigate the emergency treatment and clinical effect when the guidewire stuck in the right atrium during central vein catheter placement for hemodialysis. Methods Five cases with guidewire stuck in the right atrium during central vein catheter placement for hemodialysis from January 2011 to July 2018 admitted into the First Affiliated Hospital of Zhejiang University were retrospectively analyzed. In two cases, the guidewires were found completely stuck when the insert depth was about 20 cm. The guidewires were not able to move forward nor backward. In the other three cases, the guidewires could be moved forward but not backward with the insert depth at about 18 cm. All patients received emergent computed tomography angiography (CTA) or digital subtraction angiography (DSA) imaging. Images showed that the guidewires were stuck in the right atrium near the ventricular valve. The guidewire core drawing method, the multipurpose angiography (MPA) catheter capturing method and the manual guidewire adjusting method were used for emergent treatment. Results One patient with completely stuck guidewire was successfully treated with guidewire core drawing method and the temporary central vein catheter catheterization through the internal jugular vein was performed under DSA. In a completely stuck case and a retrogradely stuck case, the J-shaped ends of the warped guidewires were captured into the MPA catheter, and the guidewires were then withdrawn from right atriums along with the contrast catheter. In the other 2 retrogradely stuck cases, under DSA, the guidewires were repeatedly pushed, the direction of J-shaped ends was manually adjusted, and then the guidewires were repeatedly pushed and pulled until catheters can be pulled out of the right atriums. The later 4 cases had permanent central vein catheter placement with the same guidewire after the stuck guidewires were withdrawn from the right atrium and readjusted. Conclusions All three methods can successfully solve the emergent situation of the stuck guidewire in the right atrium. For patients with completely stuck guidewires, the MPA catheter capturing method can be simpler, safer, and more effective.

Objective To compare the prognosis of hemodialysis (HD) and peritoneal dialysis (PD) in end-stage renal disease (ESRD) patients without diabetes mellitus and identify related influencing factors. Methods Patients who started hemodialysis with an arteriovenous graft or fistula or PD in the First Affiliated Hospital of Zhengzhou University from January 1, 2013 to February 1, 2019 were included. They were followed up until May 1, 2019. The patients were divided into HD group and PD group according to the initial dialysis modality. Kaplan-Meier method was used to obtain survival curves, the Cox regression model was used to evaluate influence factors for survival rates, and the inverse probability of treatment weighting (IPTW) was used to eliminate influence of the confounders in the groups. Results There were 371 patients with maintenance dialysis enrolled in this study, including 113 cases (30.5%) in HD group and 258 cases (69.5%) in PD group. At baseline, the scores of standard mean difference (SMD) in age, body mass index (BMI), combined with cerebrovascular disease, Charlson comorbidity index (CCI), blood potassium, plasma albumin and hemoglobin between the two groups were greater than 0.1. The score of SMD decreased after IPTW, and the most data were less than 0.1, which meant that the balance had been reached between the two groups. The Kaplan-Meier survival curve showed that the cumulative survival rates had no significant difference for all-cause death before using IPTW between the two groups (Log-rank χ²=0.094, P=0.759). After adjusting for confounders with IPTW, the Kaplan-Meier survival curve showed that the cumulative survival rates still had no significant difference for all-cause death between the two groups (Log-rank χ²=2.090, P=0.150). Univariate Cox regression analysis showed that there was no significant difference between HD and PD on survival rates in ESRD patients without diabetes mellitus for all-cause death (PD/HD, HR=1.171, 95%CI 0.426-3.223, P=0.760). Multivariate Cox regression analysis showed that there was no significant difference between HD and PD on survival rates in ESRD patients without diabetes mellitus (PD/HD, HR=1.460, 95%CI 0.515-4.144, P=0.477), and high plasma albumin (HR=0.893, 95%CI 0.813-0.981, P=0.019) was an independent protective factor for survival in ESRD patients without diabetes mellitus. There was still no significant difference between HD and PD on survival rates in ESRD patients without diabetes mellitus after using IPTW (PD/HD, HR=1.842, 95%CI 0.514-6.604, P=0.348). Conclusion The difference of cumulative survival rates between HD and PD is not significant in ESRD patients without diabetes mellitus.

Objective To explore the clinical characteristics and risk factors of maintenance hemodialysis (MHD) patients combined with infection-related hospitalization. Methods Patients with MHD from December 1, 2013 to February 28, 2018 were retrospectively selected and then followed up for at least 1 year until February 28, 2019. Baseline data including demographic and clinical data of patients were collected. According to whether the infection-related hospitalization occurred, patients were divided into infection group and non-infection group. The clinical characteristics and related factors were compared between the two groups. Logistic regression model was used to analyze the influencing factors. Results A total of 392 patients were included in the study. Two hundred and fifty-five cases were males, accounting for 65.1%. The age was (59.39±15.28) years old. The infection rate of diabetic kidney disease patients was the highest (32.2%). The main site of infection was the lung, accounting for 78.4%, which was far higher than the catheter-related infection in the second position. After infection, quinolones and cephalosporins were often the preferred drugs. Compared with the non-infection group, the infection group had older age [(62.96±15.16) years vs (57.98±15.12) years, t=-2.607, P=0.004], higher proportion of comorbid diabetes (45.9% vs 32.4%, χ²=6.334, P=0.012) and previous smoking history (30.6% vs 18.5%, χ²=6.831, P=0.009), longer time of first dialysis stay [13.0(9.0, 18.0) d vs 12.0(9.0, 17.5) d, Z=3.659, P=0.001] and lower hemoglobin [(74.43±19.93) g/L vs (79.06±17.10) g/L, t=1.612, P=0.022], albumin [(32.63±5.33) g/L vs (33.99±6.14) g/L, t=2.062, P=0.029] and red blood cell count [2.53×10¹²/L (2.06×10¹²/L, 3.06×10¹²/L) vs 2.68×10¹²/L(2.28×10¹²/L, 3.07×10¹²/L), Z=2.118, P=0.034]. Multivariate logistic analysis found that older age (every 1 year, OR=1.016, 95%CI 1.003-1.030, P=0.017) and longer hospital stay at first dialysis (every 1 d, OR=1.047, 95%CI 1.014-1.080, P=0.008) were independent risk factors, and higher hemoglobin (every 1 g/L, OR=0.987, 95%CI 0.975-0.999, P=0.033) was a protective factor for infection-related hospitalization in MHD patients. Conclusions MHD patients with diabetic kidney disease have the highest infection incidence. The incidence of pulmonary infection is much higher than other types of infection such as catheter-related infection, urinary tract infection and sepsis. Aging and low hemoglobin are risk factors for MHD patients to prone to co-infection.

Objective To evaluate the efficacy and safety of lenalidomide plus dexamethasone (LD) in patients with proliferative glomerulonephritis with monoclonal immunoglobulin deposits (PGNMID). Methods The clinicopathological data of PGNMID patients who were treated with LD protocol from January 2010 to October 2019 were retrospectively analyzed. Results All of 6 patients received LD treatment for≥3 months after renal biopsy in Jinling Hospital. During the follow-up period of 6 to 19 months, 3 patients achieved renal remission, and the renal remission rate was 50%(3/6). Light microscopy showed membranoproliferative glomerulonephritis and immunofluorescence showed single kappa type IgG3 was deposited in the mesangial region and the vascular loop. Before taking LD scheme, the median urinary protein were 7.76(1.27, 14.57) g/24 h, the median serum creatinine was 118.5(70.7, 289.1) μmol/L, and the median albumin was 34.5(22.4, 37.5) g/L. The concentration of serum free kappa and lambda light chain was increased in 5 patients, but the serum free light chain ratio was normal. Hypocomplementemia was detected in two cases. Six patients underwent bone marrow flow cytometry, and 2 patients had elevated monoclonal plasma cells, accounting for 0.7% and 0.5%, respectively. Immunofixation electrophoresis suggested that 1 patient had positive serum M protein for kappa type IgG3. At the last follow-up, median urine protein was 3.33(0.33, 11.23) g/24 h, median serum creatinine was 108.7(80.4, 160.9) μmol/L, and median albumin was 35.9(24.5, 45.6) g/L. The concentration of serum free light chain in 4 patients from 5 patients with elevated serum free light chain was lower than that before taking the drug. Decreased level of serum complement in two cases returned to normal after treatment. The M spike did not turn negative during the follow-up in one patient. Adverse events included anemia, neutropenia, limb numbness and upper respiratory tract infection. Conclusion This study reports for the first time that LD protocol may be effective in treating PGNMID, but more attention should be paid to the hematological adverse events of lenalidomide.

Objective To investigate the clinical manifestation, diagnosis and prognosis of heavy- and light-amyloidosis (AHL). Methods The clinical data of two patients with AHL in Peking University People's Hospital and 21 cases of reported literature were reviewed to clarify the clinical and prognostic characteristics of AHL. Results Compared with light-amyloidosis, most AHL patients were male, with high positive rate of blood and urine immunofixation electrophoresis and complete immunoglobulin. The manifestations of the kidneys were proteinuria, mainly composed of albumin, nephrotic syndrome and microscopic haematuria. The pathology of renal biopsy showed that Congo red staining positive substances were deposited in many sites (mesangial area，capillary wall，arteriole and renal interstitium), and immunofluorescence showed that monoclonal heavy chain with light chain (the type was consistent with the hematuria M protein) were clumpy deposition, which was consistent with amyloid deposition site. Heart involvement was rare, and the proportion of plasma cells in bone marrow was high. Conclusion AHL is rare and its clinical manifestations of AHL are different from those of light-amyloidosis. The prognosis needs to be further observed.

Objective To explore the role and mechanism of C3a-C3a receptor (C3aR) in the progression of autosomal dominant polycystic kidney disease (ADPKD). Methods Renal tissues of ADPKD patients and PKD1 knockout mice were collected. Then the expression of C3a-C3aR, Ki67 and F4/80 in renal tissues was observed. Macrophages were stimulated with lipopolysaccharide (LPS) and interleukin 4 respectively. The expression of C3aR, TNF-α, typing markers and related signal pathway proteins was detected in each group. PKD1 knockout mice were treated with C3aR inhibitor SB290157 (1 mg/kg). Renal pathology, cyst-related indicators and renal function were observed. Results The expression of C3a and C3aR in ADPKD was up-regulated (both P<0.05); C3aR and F4/80 were co-located in the kidney of polycystic kidney disease (PKD) mice, indicating that C3aR was mainly expressed on membrane of macrophages. In vitro, the expression of C3aR was up-regulated in M1 macrophages (P<0.05). After the stimulation of C3a, the expression of iNOS, TNF-α and IL-6 mRNA in M1 macrophages were up-regulated (all P<0.05), as well as the secretion of TNF-α, indicating that C3a not only affected the expression of inflammatory factors of M1 macrophages, but also affected the inflammatory microenvironment. In addition, C3a significantly activated Akt in M1 macrophages (P<0.05). Compared with the control group, the treatment group showed a decrease in C3a-C3aR as well as serum BUN, Scr, cyst index, and two kidneys weight/body weight (2KW/BW) (all P<0.05), and ADPKD related pathway protein expression such as p-ERK and p-P65 was significantly down-regulated (all P<0.05). Conclusions The increased C3a in polycystic kidney tissue causes infiltration and activation of macrophages through C3aR, and then promotes ADPKD progression. The mechanism may be mediated by Akt activation and increased TNF-α production. C3aR antagonist is a potential research direction in the treatment of ADPKD.

Objective To investigate the expression of microRNA-155 (miR-155) in serum and kidney of C57BLKS/db (db/db) mice and its role in the pathogenesis of diabetic kidney disease (DKD). Methods The db/db mice (n=24) were divided into 6, 8, and 10 weeks old groups (n=8) with age increasing according to the random number table, and C57BL/6 mice of the same age were used as control group. The expression of miR-155 in mouse serum and kidney tissue was determined using real-time quantitative PCR. The mRNA and protein expression of Ets-1, eNOS, AGTR1 in renal tissues was verified by real-time quantitative PCR, Western blotting and immunohistochemistry. Results Compared with the control group, the expression of miR-155 in serum of db/db mice at 6, 8 and 10 weeks of age were significantly increased (all P<0.01), and the increase of miR-155 was most obvious at 10 weeks of age (P<0.01). Meanwhile the expression of miR-155 in kidney tissues of 6, 8 and 10 weeks old db/db mice was significantly up-regulated (all P<0.01), and the highest expression of miR-155 was at 10 weeks of age (P<0.01). Immunohistochemistry showed that Ets-1, eNOS and AGTR1 were localized in glomerular endothelial cells. The results of real-time quantitative PCR showed that the mRNA expression of Ets-1, eNOS and AGTR1 were down-regulated in the kidney tissues of db/db mice at 6, 8 and 10 weeks of age compared to the control(all P<0.05), and the level of down-regulation was the most obvious at 10 week. Western blotting results showed that there was no significant change in Ets-1, eNOS and AGTR1 in 6-week-old db/db mice compared to the control group; the eNOS protein expression was down-regulated at 8 weeks of age (P<0.05); the expression of AGTR1 protein was down-regulated (P<0.05), and the protein expression of Ets-1 and eNOS were significantly down-regulated at 10-week age (both P<0.01). Conclusions The expression of miR-155 in serum and kidney tissues of db/db mice increases during the progression of DKD, while the expression of miR-155 target genes Ets-1, eNOS and AGTR1 decreases with the progression of DKD. MiR-155 may participate in the development and progression of DKD by inhibiting its target genes Ets-1, eNOS and AGTR1, affecting endothelial cell function.