Methicillin-resistant Staphylococcus aureus nasal carriage among patients on haemodialysis with newly inserted central venous catheters.

BACKGROUND: Although methicillin-resistant Staphylococcus aureus (MRSA) nasal colonization is common among end-stage kidney disease patients undergoing haemodialysis, few studies were focused on MRSA nasal carriers among haemodialysis patients with central venous catheters (CVCs). The aim of this study is to evaluate the risk factors, various clinical outcomes and effect of decolonization for MRSA nasal colonization among patients on haemodialysis via CVCs. METHODS: This was a single-centre non-concurrent cohort study of 676 patients who had new haemodialysis CVCs inserted. They were all screened for MRSA colonization via nasal swabs and were categorized into two groups: MRSA carriers and MRSA noncarriers. Potential risk factors and clinical outcomes were analysed in both groups. All MRSA carriers were given decolonization therapy and the effect of decolonization on subsequent MRSA infection was also performed. RESULTS: Eighty-two patients (12.1%) were MRSA carriers. Multivariate analysis showed that MRSA carrier (OR 5.44; 95% CI 3.02-9.79), long-term care facility resident (OR 4.08; 95% CI 2.07-8.05), history of Staphylococcus aureus infection (OR 3.20; 95% CI 1.42-7.20) and CVC in situ > 21 days (OR 2.12; 95% CI 1.15-3.93) were independent risk factors for MRSA infection. There was no significant difference in all-cause mortality between MRSA carriers and noncarriers. The MRSA infection rates were similar between MRSA carriers with successful decolonization and those who had failed/incomplete decolonization in our subgroup analysis. CONCLUSION: MRSA nasal colonization is an important cause of MRSA infection among haemodialysis patients with CVCs. However, decolonization therapy may not be effective in reducing MRSA infection.

Immunosuppressive Medication Adherence in Kidney Transplant Recipients During the COVID-19 Pandemic: A Cross-Sectional Study in Hong Kong.

BACKGROUND: The coronavirus disease 2019 (COVID-19) pandemic has put an enormous burden on health care systems worldwide. Limited access to medical care and fear of increased infective risks due to the use of immunosuppressive medication (IM) have increased concerns about IM adherence in kidney transplant recipients (KTRs). The aim of this study was to determine the various dimensions of IM nonadherence in KTRs during the COVID-19 pandemic. METHODS: This was a single-center, cross-sectional study using a convenient sampling approach. KTRs with follow-up in Queen Elizabeth Hospital, Hong Kong between May 1, 2020 and September 30, 2020, were invited to complete a self-reported questionnaire on IM adherence. The sociodemographic factors associated with IM adherence were extracted from medical records. RESULTS: Overall, 210 patients completed the questionnaires. The overall IM nonadherence rate was 35.2% in the 4 weeks before survey completion. None of the patients stopped taking IMs without instructions from their health care providers. The most common pattern of IM nonadherence was timing adherence (n = 63; 30.1%), followed by dose-skipping item. Among the different sociodemographic factors studied, only marital status was an independent risk factor of IM nonadherence (odds ratio, 1.97; 95% confidence interval, 1.04-3.72; P = .03). CONCLUSIONS: The impact of COVID-19 on IM adherence in KTRs was not significant. All the patients continued their IM despite of the pandemic. Good family support can have a positive influence on treatment adherence in KTRs during the COVID-19 pandemic.

Impact of COVID-19 Pandemic on Organ Donation in Hong Kong: A Single-Center Observational Study.

INTRODUCTION: The coronavirus disease 2019 (COVID-19) pandemic was expected to have a negative impact on organ donation. With the differences in health care systems and lockdown policies in various regions, the pandemic's effect on organ donation and transplant service may vary. Most of the deceased donor organ referrals in our hospital came from non-intensive care units (ICUs). The objective of this study is to report our experience and quantify the effects of the COVID-19 pandemic on deceased donor organ donation in our center. METHODS: This was a retrospective observational study comparing the deceased donor organ donation activity during the period January 23 to November 30, 2020 with the same period in 2018 in Queen Elizabeth Hospital, Hong Kong. RESULTS: There was a 26.9% reduction in deceased donor organ donor referral in 2020 compared with 2018. No significant difference in the proportion of referrals from ICU or non-ICU areas between the 2 time periods was observed. The brain death confirmation rate was significantly higher in 2020 (40.8% vs 20.2%, P = .003). Nine patients had family consent for organ donation in 2020 (vs 7 patients in the same period in 2018). There were no significant differences in consent rate and number of recovered organs between the 2 periods. CONCLUSIONS: With effective measures to limit the spread of COVID-19 in a community, it is possible to support the needs of both patients with COVID-19 and deceased donor organ donation services.

Influence of CYP3A5 Genetic Polymorphism on Long-Term Renal Function in Chinese Kidney Transplant Recipients Using Limited Sampling Strategy and Abbreviated Area Under the Curve for Tacrolimus Monitoring.

INTRODUCTION: Although the association between CYP3A5 gene polymorphism and tacrolimus dosing requirements was well established, the impact on how CYP3A5 genotype affects the acute rejection and long-term renal function in patients who received kidney transplants and were treated with tacrolimus remained controversial. DESIGN: Sixty-seven Chinese patients with kidney transplants receiving de novo tacrolimus-based immunosuppressive therapy with known CYP3A5 genotype were divided into 2 groups. Those with at least 1 CYP3A5*1 allele were CYP3A5 expressers while homozygotes for the mutant allele CYP3A5*3 were nonexpressers. Instead of trough level, our center used abbreviated area under the curve for tacrolimus monitoring. Primary outcome was the long-term renal function between both groups while secondary outcomes included the weight-adjusted daily tacrolimus dose, graft survival, incidence of biopsy-proven acute rejection (BPAR), opportunistic infection, and cancer. RESULTS: Thirty-five (52.2%) patients were CYP3A5 expressers while 32 were nonexpressers. Mean daily tacrolimus dose in the CYP3A5 expressers and nonexpressers was 0.08 (0.03) and 0.05 (0.02) mg/kg, respectively (P < .01). Starting from 1-month posttransplant, the renal function was comparable between both groups, which persisted up to 10-year. Ten patients experienced BPAR rejection and there was no significant difference in the rejection-free survival between both groups (P = .87). There was also no significant difference in the death-censored graft survival between both groups (P = .86). Finally, the incidence of opportunistic infection and posttransplant cancer was similar between them. DISCUSSION: There was no significant difference in renal function, graft survival, and acute rejection between CYP3A5 expressers and nonexpressers.

Two related Chinese Fabry disease patients with a p.N215S pathological variant who presented with nephropathy.

Fabry disease is an X-linked lysosomal storage disease resulting from a mutation in the GLA gene that encodes α-galactosidase A. The p.N215S (c.644A > G [p.Asn215Ser]) genotype is the most common later-onset variant reported in individuals of European or North American descent. It is usually referred to as a cardiac variant, although manifestations in other organ systems have been observed. In this report, we describe a nephropathy presentation in two related Chinese Fabry disease patients with p.N215S.

Impact of CYP3A5 Genetic Polymorphism on Intrapatient Variability of Tacrolimus Exposure in Chinese Kidney Transplant Recipients.

BACKGROUND: Although high tacrolimus (FK) intrapatient variability (IPV) was shown to be associated with poor graft outcome in kidney transplant recipients (KTRs), it is uncertain whether there is any association between the CYP3A5 genotype and IPV of FK concentrations. Instead of trough level, we use calculated abbreviated AUC0-12 to investigate the impact of CYP3A5 genetic polymorphism on IPV of FK pharmacokinetics. METHODS: We conducted a retrospective, single-center study of 86 adult Chinese KTRs with known CYP3A5 genotype. Coefficient of variation (CV) was used for the quantification of FK IPV. CV of dose-normalized FK AUC0-12 was calculated and was compared between the CYP3A5 expresser group and nonexpresser group. RESULTS: Forty-one patients (47.7%) were classified as CYP3A5 expressers while 45 were nonexpressers. No significant differences in the baseline characteristics were found between expressers and nonexpressers. CYP3A5 expressers required 1.8 times higher FK dose compared with the nonexpressers. There was no significant difference in the FK CV between CYP3A5 expressers (18.2 ± 7.5%) and nonexpressers (16.7 ± 5.7%) (P = .31). CONCLUSION: The IPV of FK exposure was not associated with CYP3A5 genotype in stable KTRs. Further studies should focus on other factors such as medication nonadherence, which may explain FK IPV.

Prevalence and impact of anxiety and depression in Chinese peritoneal dialysis patients: A single centre study.

AIM: Anxiety and depression are prevalent among patients with end stage renal failure. However, data concerning their role in the subsequent peritonitis and hospitalization was scarce. The aim of this study was to examine the prevalence of psychological problems in our Chinese peritoneal dialysis (PD) patients and its association with subsequent clinical outcome. METHODS: This was a single-centre prospective cohort study. All patients newly started on PD between 1 September 2012 and 31 December 2014 were recruited. Hospital Anxiety Depression Scale was used to categorize the patients into high score group (HSG) and low score group (LSG). Higher score reflects higher emotional distress. RESULTS: A total of 132 patients were recruited. Seventy-five patients (55%) were categorized as HSG. Higher overall peritonitis rate and Gram-positive organism associated peritonitis rate were observed in HSG (P = 0.012 and P = 0.016, respectively). The hospitalization rates in HSG and LSG were 1.20 episodes per patient-year and 1.05 episodes per patient-year respectively. Both high CCI (OR 1.33, 95% CI 1.10-1.62, P < 0.01) and HSG (OR 3.17, 95% CI 1.27-7.93, P = 0.01) were independent risk factors for PD peritonitis. CONCLUSION: Anxiety and depression were also common among Chinese PD patients. Those in HSG were more likely to develop PD peritonitis. These psychological symptoms deserved early detection. Further studies are needed to investigate whether intervention can improve the clinical outcome of these patients.

Effect of incident nocturnal home hemodialysis versus incident continuous ambulatory peritoneal dialysis on employment rate, clinical, and laboratory outcomes: A 1-year retrospective observation study.

INTRODUCTION: While studies demonstrated favorable outcomes of nocturnal home hemodialysis (NHHD), direct comparison on employment rate, clinical and laboratory outcomes between the NHHD and continuous ambulatory peritoneal dialysis (CAPD) had not been previously performed. METHODS: A 1-year retrospective observation study was performed in 20 incidents alternate night NHHD and 81 incident CAPD patients of Chinese ethnicity, who were sex, diabetic status, and Charlson comorbidity index matched, but not age due to our center's age limit for NHHD enrollment. The primary outcome was the difference in employment rate at 1 year. Secondary outcomes included differences in clinical parameters (weight, blood pressure, number of antihypertensive medication, dosage of phosphate binders, and erythropoietin stimulating agent) and laboratory parameters (residual renal function, mineral metabolic markers, hemoglobin). FINDINGS: NHHD subjects were 5 years younger than CAPD patients, and they had higher employment rate (80% vs. 33.3%, P < 0.01) at 1 year, with age-adjusted odds ratio for employment was 6.10 (95% confidence interval 1.77-20.99, P = 0.04). They consumed less aluminum-based phosphate binder (0 vs. 1800 mg, P < 0.01), but showed no significant disparities in other clinical parameters. Residual renal function in both groups declined comparably, nonetheless NHHD group had lower serum phosphate (1.37 vs. 1.71 mmol/L, P = 0.01) and calcium phosphate product (3.13 vs. 4.12 mmol2 /L2 , P < 0.01), with similar hemoglobin levels. DISCUSSION: NHHD appeared to offer higher employment rate, lower dosage of aluminum-based phosphate binder and mineral metabolic markers at 1 year compared with CAPD in Hong Kong.

Posttransplant lymphoproliferative disorders in kidney transplant recipients: a retrospective cohort analysis over two decades in Hong Kong.

OBJECTIVE: To characterize the posttransplant lymphoproliferative disorders (PTLD) including the Epstein-Barr virus (EBV) status, histological subgroups, site of occurrence and the clinical outcome in the Chinese kidney transplant recipients. METHODS: A retrospective cohort study of 1, 227 adult kidney transplant recipients who were followed up in two transplant centers in Hong Kong over two decades. RESULTS: 23 (1.9%) patients developed PTLD. Median duration from transplant to PTLD was 104 (5-252) months. Six patients (26.1%) had early PTLD and 17 (73.9%) had late PTLD. Ten (43%) developed PTLD >10 years after transplant. All patients in early PTLD group were EBV-positive. In the late PTLD group, 60% were EBV-negative and 40% EBV-positive. More than 90% of cases were monomorphic PTLD with majority being diffuse large B cell lymphoma. Bone marrow was the most common extranodal site. The overall treatment response rate was 52.2 %. None of the patients developed rejection or relapse after PTLD. At a median follow-up of 9 (1-79) months after PTLD, 18 patients died. Patient survival was 48% at 1 year and 30% at 3 years and death-censored allograft survival was 82% at 1year and 73% at 3 years. CONCLUSION: Late PTLD is common. Careful adjustment of immunosuppression, close monitoring of patients, increased awareness and early detection of the disease are essential.

Cancer risk in patients with diabetic nephropathy: A retrospective cohort study in Hong Kong.

Diabetic nephropathy (DN) is a leading cause of end-stage kidney disease nowadays. Certain cancers are more common in patients with diabetes mellitus. However, there are no data concerning the cancer pattern in patients with DN. The aim of this study is to investigate the site-specific cancer risk and mortality in these patients.A retrospective cohort study of 5643 DN patients between 2000 and 2015 was conducted in 2 large hospitals in Hong Kong. Incidence and mortality of various cancers were compared with those of general population using standardized incidence ratios (SIRs) and standardized mortality ratios (SMRs) respectively.With 24,726 person-years follow-up, 250 cancers were diagnosed. Overall cancer incidence was similar between DN patients and the general population (SIR 1.05, 95% confidence interval [CI] 0.92-1.19). However, certain site-specific cancers are increased in DN patients: the highest risk was observed for laryngeal cancer (SIR 3.03, 95% CI 1.11-6.60), followed by cancers of liver (SIR 1.96, 95% CI 1.35-2.76) and colorectum (SIR 1.92, 95% CI 1.53-2.37), but the risk of prostate cancer was lower (SIR 0.48, 95% CI 0.21-0.95) in the males with DN. The SMR of all cancers was 1.17 (95% CI 1.01-1.37). For individual specific site, only colorectal cancer carried a significant higher mortality risk (SMR 2.45, 95% CI 1.82-3.23).Our data suggested that DN is associated with increased incidence of cancers of colorectum, liver, and larynx but decreased incidence of prostate cancer. Moreover, there is increased mortality of colorectal cancer in patients with DN.

Risk Factors and Outcomes of Vancomycin-Resistant Enterococcus Colonization in Patients on Peritoneal Dialysis: A Single-Center Study in Hong Kong.

BACKGROUND: Vancomycin-resistant Enterococcus (VRE) colonization is common among patients with chronic kidney disease. However, data concerning VRE colonization among patients receiving peritoneal dialysis (PD) is lacking. The aim of this study is to evaluate the risk factors and various clinical outcomes for VRE colonization among PD patients. METHODS: This is a retrospective cohort study of 166 PD patients who were hospitalized between 1 August 2013 and 31 July 2014. They were screened for VRE colonization status during a major VRE outbreak in Hong Kong in 2013 and were then categorized into 2 groups: VRE-positive and VRE-negative. The primary outcome was all-cause mortality while the secondary outcomes included VRE infection, PD-related peritonitis, and length of hospitalization. RESULTS: Twenty-eight patients (16.9%) belonged to the VRE-positive group. Multivariate analysis showed that previous contact with VRE-positive patients (odds ratio [OR]: 417.86; 95% confidence interval [CI]: 17.21 - 10,147.26, p < 0.01), vancomycin use in previous 3 months (OR: 130.32; 95% CI: 5.35 - 3,176.30, p < 0.01), and old age (OR: 1.13; 95% CI: 1.02 - 1.24, p = 0.02) were the independent risk factors for VRE colonization. Patients in the VRE-positive group had significantly longer length of hospitalization, but there was no significant difference in all-cause mortality and peritonitis-free survival. CONCLUSION: Vancomycin-resistant Enterococcus colonization is important among hospitalized PD patients. Cautious use of antibiotics and infection control measures are necessary to prevent VRE spreading, especially in high-risk patients.

Conversion to mammalian target of rapamycin inhibitors in kidney transplant recipients with de novo cancers.

OBJECTIVE: To investigate the impact of mammalian target of rapamycin (mTOR) inhibitor conversion together with minimization of calcineurin inhibitor on allograft outcome and patient survival in kidney transplant recipients with post-transplant cancers. METHODS: A retrospective study of all kidney transplant recipients diagnosed to have post-transplant cancers between the period 1/1/1994 and 30/6/2015. Patients were divided into 2 groups: mTOR inhibitor group and non-conversion group. Outcome included allograft function, patient survival, graft survival, acute rejection and cancer recurrence. RESULTS: 115 patients (56 in mTOR inhibitor group and 59 in non-conversion group) were analyzed. Median follow up was 28 months (range: 1 month - 20 years). The allograft function at 1-year remained similar between both groups. There was no significant difference in the patient survival, graft survival and rejection free survival between both groups. More patients in the non-conversion group developed recurrence of cancers than mTOR inhibitor group but statistically not significant. CONCLUSIONS: Use of mTOR inhibitors together with calcineurin inhibitor minimization offer a reasonable option in kidney transplant recipients who developed post-transplant cancers in view of stable renal function, low rejection rate and low cancer recurrence rate.

A Modified Protocol with Improved Detection Rate for Mis-Matched Donor HLA from Low Quantities of DNA in Urine Samples from Kidney Graft Recipients.

BACKGROUND: Urine from kidney transplant recipient has proven to be a viable source for donor DNA. However, an optimized protocol would be required to determine mis-matched donor HLA specificities in view of the scarcity of DNA obtained in some cases. METHODS: In this study, fresh early morning urine specimens were obtained from 155 kidney transplant recipients with known donor HLA phenotype. DNA was extracted and typing of HLA-A, B and DRB1 loci by polymerase chain reaction-specific sequence primers was performed using tailor-made condition according to the concentration of extracted DNA. RESULTS: HLA typing of DNA extracted from urine revealed both recipient and donor HLA phenotypes, allowing the deduction of the unknown donor HLA and hence the degree of HLA mis-match. By adopting the modified procedures, mis-matched donor HLA phenotypes were successfully deduced in all of 35 tested urine samples at DNA quantities spanning the range of 620-24,000 ng. CONCLUSIONS: This urine-based method offers a promising and reliable non-invasive means for the identification of mis-matched donor HLA antigens in kidney transplant recipients with unknown donor HLA phenotype or otherwise inadequate donor information.

Cancer Incidence and Mortality in Chronic Dialysis Population: A Multicenter Cohort Study.

BACKGROUND: Different studies in the past have shown that the risk of cancer development is increased in chronic dialysis patients. However, data concerning the cancer risk in Asian dialysis patients was scarce. More importantly, there was lack of information about the cancer-specific mortality in dialysis patients. METHODS: A multicenter retrospective cohort study of 6,254 patients who started either chronic peritoneal dialysis or hemodialysis between 1994 and 2014 in 4 renal units in Hong Kong. Patterns of cancer incidence and mortality in our dialysis patients were compared with those of the general population using standardized incidence ratios (SIRs) and standardized mortality ratios (SMRs) respectively. RESULTS: With 14,887 person-years of follow-up, 220 cancers were recorded. The SIR of all cancers was 1.44 (95% CI 1.26-1.65). A trend of an increased SIR was observed in young patients and within the first year of dialysis. Colorectum was the most common site of cancer (20%) while kidney cancer carried the highest risk (SIR 12.28, 95% CI 8.44-17.08). The SMR of all cancers was 0.91 (95% CI 0.72-1.13) and only kidney cancer had higher cancer mortality risk (SMR 4.92, 95% CI 1.80-10.70). SMR was highest in young patients and then decreased with age. CONCLUSIONS: The incidence of cancers in our chronic dialysis patients was elevated. Our findings of substantially increased risks in young patients, particularly in relation to kidney cancer, suggest that we can adopt a more individualized approach to cancer screening in chronic dialysis patients.

Impact of a low-glucose peritoneal dialysis regimen on fibrosis and inflammation biomarkers.

BACKGROUND: The impact of a low-glucose peritoneal dialysis (PD) regimen on biomarkers of peritoneal inflammation, fibrosis and membrane integrity remains to be investigated. METHODS: In a randomized, prospective study, 80 incident PD patients received either a low-glucose regimen comprising Physioneal (P), Extraneal (E) and Nutrineal (N) (Baxter Healthcare Corporation, Deerfield, IL, USA) (PEN group), or Dianeal (control group) for 12 months, after which both groups continued with Dianeal dialysis for 6 months. Serum and dialysate levels of vascular endothelial growth factor (VEGF), decorin, hepatocyte growth factor (HGF), interleukin-6 (IL-6), macrophage migration inhibitory factor (MIF), hyaluronan (HA), adiponectin, soluble-intracellular adhesion molecule (s-ICAM), vascular cell adhesion molecule-1 (VCAM-1) and P-selectin, and dialysate cancer antigen 125 (CA125), were measured after 12 and 18 months. This paper focuses on results after 12 months, when patients in the PEN group changed to glucose-based PD fluid (PDF). RESULTS: At the end of 12 months, effluent dialysate levels of CA125, decorin, HGF, IL-6, adiponectin and adhesion molecules were significantly higher in the PEN group compared to controls, but all decreased after patients switched to glucose-based PDF. Macrophage migration inhibitory factor level was lower in the PEN group but increased after changing to glucose-based PDF and was similar to controls at 18 months. Serum adiponectin level was higher in the PEN group at 12 months, but was similar in the 2 groups at 18 months. Body weight, residual renal function, ultrafiltration volume and total Kt/V did not differ between both groups. Dialysate-to-plasma creatinine ratio at 4 h was higher in the PEN group at 12 months and remained so after switching to glucose-based PDF. CONCLUSION: Changes in the biomarkers suggest that the PEN PD regimen may be associated with better preservation of peritoneal membrane integrity and reduced systemic vascular endothelial injury.

Hemodialysis catheter insertion using transrenal approach.

We report a patient suffering from end-stage renal disease (ESRD) because of lupus nephritis presented with exhausted vascular access after multiple arteriovenous grafts creation and hemodialysis catheters insertion. A rare percutaneous transrenal approach was finally used for the insertion of dialysis catheter. After 2 years, this hemodialysis catheter was complicated by blockage but was successfully replaced by a new catheter via the same site. Our report shows that the transrenal route of hemodialysis catheter insertion can provide a glimpse of hope for those ESRD patients with exhausted vascular access.