Infectious complications in dialysis--epidemiology and outcomes. Nat Rev Nephrol. 2012;8:77-88. [PMID: 22183504 DOI: 10.1038/nrneph.2011.194]

Integrated home dialysis model: facilitating home-to-home transition

Peritoneal dialysis (PD) and home hemodialysis (HHD) are the two home dialysis modalities offered to patients. They promote patient autonomy, enhance independence, and are generally associated with better quality of life compared to facility hemodialysis. PD offers some advantages (enhanced flexibility, ability to travel, preservation of residual kidney function, and vascular access sites) but few patients remain on PD indefinitely due to peritonitis and other complications. By contrast, HHD incurs longer and more intensive training combined with increased upfront health costs compared to PD, but is easier to sustain in the long term. As a result, the integrated home dialysis model was proposed to combine the advantages of both home-based dialysis modalities. In this paradigm, patients are encouraged to initiate dialysis on PD and transfer to HHD after PD termination. Available evidence demonstrates the feasibility and safety of this approach and some observational studies have shown that patients who undergo the PD-to-HHD transition have clinical outcomes comparable to patients who initiate dialysis directly on HHD. Nevertheless, the prevalence of PD-to-HHD transfers remains low, reflecting the multiple barriers that prevent the full uptake of home-to-home transitions, notably a lack of awareness about the model, home-care "burnout," clinical inertia after a transfer to facility HD, suboptimal integration of PD and HHD centers, and insufficient funding for home dialysis programs. In this review, we will examine the conceptual advantages and disadvantages of integrated home dialysis, present the evidence that underlies it, identify challenges that prevent its success and finally, propose solutions to increase its adoption.

High-risk adverse drug reactions: consideration of limited dialysis therapy for toxic epidermal necrolysis (TEN)

Toxic epidermal necrolysis (TEN) is a rare but often lethal drug reaction involving the skin. Treatment is often centered around suppurative care, and the mortality rate remains unacceptably high, although the clinical and epidemiological features of TEN have been well documented for decades. Recent studies have placed an emphasis on certain medications in the pathophysiology of severe TEN, and our colleagues previously reported several cases of clinical improvement in TEN patients following hemodialysis. Here, we discuss the major considerations for initiating dialysis in TEN patients. By doing so, we hope to encourage others to explore this potential avenue for treating TEN, one of the most serious medical emergencies in the field of dermatology.

Guidelines on vascular access for hemodialysis from the Brazilian Society of Angiology and Vascular Surgery

Chronic kidney disease is a worldwide public health problem, and end-stage renal disease requires dialysis. Most patients requiring renal replacement therapy have to undergo hemodialysis. Therefore, vascular access is extremely important for the dialysis population, directly affecting the quality of life and the morbidity and mortality of this patient population. Since making, managing and salvaging of vascular accesses falls within the purview of the vascular surgeon, developing guideline to help specialists better manage vascular accesses for hemodialysis if of great importance. Thus, the objective of this guideline is to present a set of recommendations to guide decisions involved in the referral, evaluation, choice, surveillance and management of complications of vascular accesses for hemodialysis.

Progress in the application of the neutrophil-to-lymphocyte ratio in dialysis-related complications

The neutrophil-to-lymphocyte ratio (NLR) is a novel predictive biomarker that reflects systemic inflammatory status and is routinely measured in blood tests. Owing to its ease of use and affordability, it is being increasing used as a prognostic indicator of cardiovascular disease, tumors, autoimmune disorders, and kidney disease. In recent years, a number of studies have demonstrated the clinical utility of the NLR in identifying and predicting complications associated with hemodialysis and peritoneal dialysis, including cardiovascular disease and infection. This review aimed to provide a new perspective on the application of the NLR as a valuable tool enabling clinicians to better assess the occurrence and prognosis of complications in patients undergoing dialysis.

Short-term outcomes of colorectal cancer surgery in patients with dialysis: a systematic review and meta-analysis

PURPOSE

This systematic review and meta-analysis aimed to evaluate the effect of dialysis-dependent chronic kidney disease (CKD) on postoperative complications in colorectal cancer surgery.

METHODS

In April 2023, we systematically searched PubMed, the Cochrane library, and Ovid for relevant studies on short-term outcomes of colorectal cancer surgery in patients with dialysis and analyzed the findings from these studies for meta-analysis.

RESULTS

Our systematic and meta-analysis review identified seven studies involving 50713 patients. We showed that the dialysis group had higher rates of mortality (OR = 4.12, 95%CI: 2.75-6.20, P < 0.001), cardiac complications (OR = 2.45, 95%CI: 1.88-3.21, P < 0.001), and pneumonia (OR = 2.68, 95%CI: 1.83-3.93, P < 0.001). On the other hand, there were no differences in superficial/deep surgical site infection (SSI) (odds ratio [OR] = 1.17, 95%CI: 0.90-1.53, P = 0.230) and organ/space SSI (OR = 1.35, 95%CI: 1.00-1.82, P = 0.053) between the dialysis group and non-dialysis group.

CONCLUSION

Our meta-analysis showed that dialysis-dependent CKD was associated with higher rates of mortality, cardiac complications, and pneumonia after colorectal cancer surgery. However, the limitations of this meta-analysis should be taken into consideration when interpreting the results.

Invasive aspergillosis in the patient with focal segmental glomerulosclerosis initiating hemodialysis: a case report and mini-review

Background

Invasive aspergillosis (IA) is a severe form of fungal infection caused by the genus Aspergillus in immunocompromised hosts and has a high mortality rate. End-stage kidney disease (ESKD) is one of the risk factors for developing fungal infection; however, the detailed clinical and treatment course of ESKD patients with IA has been scarcely reported, especially for the patient initiating hemodialysis (HD). Here, we experienced a patient under immunosuppressive therapy for focal segmental glomerulosclerosis (FSGS) who suffered from IA involving lung and brain and resulted in initiating HD.

Case presentation

A 66-year-old male patient with a history of suspected non-tuberculosis mycobacterial lung disease was initially admitted to the hospital with minimal change disease and subsequently diagnosed as FSGS with worsening urinary protein levels. The combined treatment including immunosuppressive treatments of cyclosporin and glucocorticoids and low-density lipoprotein apheresis was initiated, and then, he experienced the symptoms of dry cough, somnolence, and disorientation, which were subsequently diagnosed as IA involving lung and brain. The patient required renal replacement therapy, and maintenance HD was continued. Despite the intensive treatment with multiple antifungals of liposomal amphotericin B, voriconazole, micafungin, and amphotericin B, the pneumonia of the patient did not improve, and he subsequently passed away.

Conclusions

We report the case of the IA under immunosuppressive treatment, who was subsequently initiated maintenance HD. The detailed clinical course of medications used to treat the patient is presented with the literature review of IA in ESKD and HD patients and those with past acid-fast bacterial infections. The careful determination of the intensity of immunosuppression and monitoring of the patient’s symptoms and early definitive diagnosis is crucial in treating IA in immunocompromised hosts with ESKD or in HD under immunosuppressive treatment, as the mortality for these patients is suspected to be high despite the intensive treatment.

Semi-Implantable Bioelectronics

Developing techniques to effectively and real-time monitor and regulate the interior environment of biological objects is significantly important for many biomedical engineering and scientific applications, including drug delivery, electrophysiological recording and regulation of intracellular activities. Semi-implantable bioelectronics is currently a hot spot in biomedical engineering research area, because it not only meets the increasing technical demands for precise detection or regulation of biological activities, but also provides a desirable platform for externally incorporating complex functionalities and electronic integration. Although there is less definition and summary to distinguish it from the well-reviewed non-invasive bioelectronics and fully implantable bioelectronics, semi-implantable bioelectronics have emerged as highly unique technology to boost the development of biochips and smart wearable device. Here, we reviewed the recent progress in this field and raised the concept of "Semi-implantable bioelectronics", summarizing the principle and strategies of semi-implantable device for cell applications and in vivo applications, discussing the typical methodologies to access to intracellular environment or in vivo environment, biosafety aspects and typical applications. This review is meaningful for understanding in-depth the design principles, materials fabrication techniques, device integration processes, cell/tissue penetration methodologies, biosafety aspects, and applications strategies that are essential to the development of future minimally invasive bioelectronics.

Aortic arch calcification affects causes of death in patients on hemodialysis: a retrospective cohort study

Background

Aortic arch calcification (AAC) is a well-known risk factor for death in patients on hemodialysis (HD); however, the causes of death among them have not been well studied. The study aimed to investigate the distribution of causes of death and long-term prognosis among different degrees of AAC in HD patients.

Methods

A retrospective cohort study was conducted on patients undergoing HD at two clinics in Japan. AAC grades 0 to 3 were categorized by chest radiograph at baseline, and mortality and causes of death were collected. A subgroup analysis was performed to evaluate the relationship between causes of death and age, diabetes mellitus, and dialysis vintage in each AAC grade.

Results

A total of 321 patients were included in the analysis. During 5.2 ± 2.1 years, 117 patients died, and the death rates in AAC grades 0, 1, 2, and 3 were 19.3% (17/88), 35.2% (51/145), 46.3% (25/54), and 70.6% (24/34), respectively. The major causes of death were cardiovascular disease (CVD, 39.3%), infection (20.5%), and malignancy (15.4%) in the entire cohort. In AAC grade 3, CVD mortality (33.3%) remains as the most common cause of death, although death of infection (29.2%) and malnutrition (16.7%) increased markedly. A subgroup analysis showed that AAC grade 3 was mostly old, non-diabetic patients with a long dialysis vintage and was susceptible to death of infection or malnutrition.

Conclusions

CVD was the most common cause of death among all AAC grades, although death of infection and malnutrition markedly increased in those with severe AAC. Attention should be paid to CVD, infection, and malnutrition in HD patients with severe AAC.

Secondary Immunodeficiency Related to Kidney Disease (SIDKD)-Definition, Unmet Need, and Mechanisms

Kidney disease is a known risk factor for poor outcomes of COVID-19 and many other serious infections. Conversely, infection is the second most common cause of death in patients with kidney disease. However, little is known about the underlying secondary immunodeficiency related to kidney disease (SIDKD). In contrast to cardiovascular disease related to kidney disease, which has triggered countless epidemiologic, clinical, and experimental research activities or interventional trials, investments in tracing, understanding, and therapeutically targeting SIDKD have been sparse. As a call for more awareness of SIDKD as an imminent unmet medical need that requires rigorous research activities at all levels, we review the epidemiology of SIDKD and the numerous aspects of the abnormal immunophenotype of patients with kidney disease. We propose a definition of SIDKD and discuss the pathogenic mechanisms of SIDKD known thus far, including more recent insights into the unexpected immunoregulatory roles of elevated levels of FGF23 and hyperuricemia and shifts in the secretome of the intestinal microbiota in kidney disease. As an ultimate goal, we should aim to develop therapeutics that can reduce mortality due to infections in patients with kidney disease by normalizing host defense to pathogens and immune responses to vaccines.

Recent advances in novel diagnostic testing for peritoneal dialysis-related peritonitis

Peritoneal dialysis-related peritonitis remains a significant complication and an important cause of technique failure. Based on current International Society for Peritoneal Dialysis guidelines, diagnosis of peritonitis is made when two of the three following criteria are met: 1) clinical features consistent with peritonitis; 2) dialysis effluent white blood cell count of >100 cells/μL; 3) positive effluent culture. However, early and accurate diagnosis can still be faulty, and emphasis has been placed on improving the timeliness and accuracy of diagnosis to facilitate early effective treatment. There have been advances in the novel diagnostic tests such as point-of-care molecular tests, genetics sequencing, mass spectrometry, and machine learning algorithm with immune fingerprinting. This article will discuss the latest evidence and updates of these tests in the management of peritoneal dialysis-related peritonitis.

Characterization of Oral Enterobacteriaceae Prevalence and Resistance Profile in Chronic Kidney Disease Patients Undergoing Peritoneal Dialysis

Chronic Kidney Disease (CKD) is a growing public-health concern worldwide. Patients exhibit compromised immunity and are more prone to infection than other populations. Therefore, oral colonization by clinically relevant members of the Enterobacteriaceae family, major agents of both nosocomial and dialysis-associated infections with frequent prevalence of antibiotic resistances, may constitute a serious risk. Thus, this study aimed to assess the occurrence of clinically relevant enterobacteria and their antibiotic resistance profiles in the oral cavity of CKD patients undergoing peritoneal dialysis (CKD-PD) and compare it to healthy controls. Saliva samples from all the participants were cultured on MacConkey Agar and evaluated regarding the levels of urea, ammonia, and pH. Bacterial isolates were identified and characterized for antibiotic resistance phenotype and genotype. The results showed that CKD-PD patients exhibited significantly higher salivary pH, urea, and ammonia levels than controls, that was accompanied by higher prevalence and diversity of oral enterobacteria. Out of all the species isolated, only the prevalence of Raoultella ornithinolytica varied significantly between groups, colonizing the oral cavity of approximately 30% of CKD-PD patients while absent from controls. Antibiotic resistance phenotyping revealed mostly putative intrinsic resistance phenotypes (to amoxicillin, ticarcillin, and cephalothin), and resistance to sulfamethoxazole (~43% of isolates) and streptomycin (~17%). However, all isolates were resistant to at least one of the antibiotics tested and multidrug resistance isolates were only found in CKD-PD group (31,6%). Mobile genetic elements and resistance genes were detected in isolates of the species Raoultella ornithinolytica, Klebsiella pneumoniae, Klebsiella oxytoca, Escherichia coli, and Enterobacter asburiae, mostly originated from CKD-PD patients. PD-related infection history revealed that Enterobacteriaceae were responsible for ~8% of peritonitis and ~ 16% of exit-site infections episodes in CKD-PD patients, although no association was found to oral enterobacteria colonization at the time of sampling. The results suggest that the CKD-induced alterations of the oral milieu might promote a dysbiosis of the commensal oral microbiome, namely the proliferation of clinically relevant Enterobacteriaceae potentially harboring acquired antibiotic resistance genes. This study highlights the importance of the oral cavity as a reservoir for pathobionts and antibiotic resistances in CKD patients undergoing peritoneal dialysis.

Belatacept Use after Kidney Transplantation and Its Effects on Risk of Infection and COVID-19 Vaccine Response

Introduction: Belatacept is a common immunosuppressive therapy used after kidney transplantation (KT) to avoid calcineurin-inhibitor (CNI) use and its related toxicities. It is unclear whether its use exposes KT recipients (KTx) to a greater risk of infection or a poorer response to vaccines. Areas covered: We reviewed PubMed and the Cochrane database. We then summarized the mechanisms and impacts of belatacept use on the risk of infection, particularly opportunistic, in two settings, i.e., de novo KTx and conversion from CNIs. We also focused on COVID-19 infection risk and response to SARS-CoV-2 vaccination in patients whose maintenance immunosuppression relies on belatacept. Expert opinion: When belatacept is used de novo, or after drug conversion the safety profile regarding the risk of infection remains good. However, there is an increased risk of opportunistic infections, mainly CMV disease and Pneumocystis pneumonia, particularly in those with a low eGFR, in older people, in those receiving steroid-based therapy, or those that have an early conversion from CNI to belatacept (i.e., <six months post-transplantation). Thus, we recommend, if possible, delaying conversion from CNI to belatacept until at least six months post-transplantation. Optimal timing seems to be eight months post-transplantation. In addition, KTx receiving belatacept respond poorly to SARS-CoV-2 vaccination.

End-Stage Renal Disease-Related Accelerated Immune Senescence: Is Rejuvenation of the Immune System a Therapeutic Goal?

End-stage renal disease (ESRD) patients exhibit clinical features of premature ageing, including frailty, cardiovascular disease, and muscle wasting. Accelerated ageing also concerns the immune system. Patients with ESRD have both immune senescence and chronic inflammation that are resumed in the so-called inflammaging syndrome. Immune senescence is particularly characterised by premature loss of thymic function that is associated with hyporesponsiveness to vaccines, susceptibility to infections, and death. ESRD-related chronic inflammation has multiple causes and participates to accelerated cardiovascular disease. Although, both characterisation of immune senescence and its consequences are relatively well-known, mechanisms are more uncertain. However, prevention of immune senescence/inflammation or/and rejuvenation of the immune system are major goal to ameliorate clinical outcomes of ESRD patients.

Critical peritonitis secondary to gastrointestinal mucormycosis in a peritoneal dialysis patient: a case report

Immunodeficient patients are susceptible to systemic fungal infections; however, these rarely cause secondary peritonitis. A 66-year-old man with multiple myeloma and diabetes mellitus on continuous ambulatory peritoneal dialysis (CAPD) presented with cloudy ascitic fluid. He had been treated with corticosteroids for 1 month for Tolosa-Hunt syndrome. We diagnosed peritoneal dialysis-related peritonitis caused by Enterococcus avium, removed the CAPD catheter, and initiated intravenous ampicillin. Computed tomography (CT) revealed an intramural gastric mass and a thinning ascending colon wall. Four days later, follow-up contrast-enhanced CT showed penetration of the ascending colon and rupture of the ileocolic artery. Emergency open surgery revealed hemorrhagic infarction with mucormycosis. We initiated intravenous liposomal amphotericin B 20 days after admission; however, he died 55 days later. Anatomical abnormalities, such as gastrointestinal perforation, should be considered for peritonitis in immunodeficient patients. Gastrointestinal mucormycosis is rare but fatal, resulting from a delay in diagnosis and consequent gastrointestinal perforation. For an early diagnosis and a favorable clinical outcome, it is important to consider the risk factors for mucormycosis, including corticosteroid use, diabetes, end-stage kidney diseases.

Puncture Site Necrosis Over Hemodialysis Native and Prosthetic Vascular Accesses

BACKGROUND

The aim of this study was to detail our experience in the management of skin necrosis/ulceration over hemodialysis vascular accesses.

METHODS

We collected demographics and operative data about patients undergoing surgery for skin necrosis over native or prosthetic vascular accesses. The different procedural techniques used and outcomes achieved were analyzed.

RESULTS

Over a six-year period (2013-2019), 593 hemodialysis accesses were created and 16 patients (50%, 8 male; median age 63.6 years, range 42-87; 12 native and 4 prosthetic accesses) were emergently/urgently treated for skin necrosis with danger of rupture (n 9), minor active bleeding (n 4) or life-threatening hemorrhage (n 3). Underlying causes were local infection, aneurysm/pseudo-aneurysm formation and venous stenosis. Most accesses were preserved. Rescue procedures consisted in excision of skin necrosis in association with aneurysmorrhaphy (n 1, 6.3%), simple closure of the venous breach (n 2, 12.5%) or resection and direct re-anastomosis (n 7, 43.8%). Concomitant endoluminal dilatation of venous outflow was needed in 7 (43.8%) cases. No intraoperative complications were observed. At a median of 13 months (range 1-39), 90% of rescued accesses were still functional.

CONCLUSIONS

Skin necrosis/ulceration over vascular access requires prompt surgical intervention ahead the risk of life-threatening hemorrhage. The rescue of a functional access is possible in most patients and provides an efficient dialysis in postoperative period.

Seroprevalence of hepatitis B, hepatitis C and HIV infection among patients undergoing haemodialysis in Buenos Aires, Argentina

Introduction. Blood-borne infections are a major cause of harm in individuals on haemodialysis (HD). In particular, knowledge about hepatitis B (HBV), hepatitis C (HCV) and human immunodeficiency virus (HIV) status in HD patients is a major concern, since these infections may cause comorbidities in this setting. There is a paucity of data regarding this issue in Argentina.Hypothesis/Gap Statement. The epidemiological surveillance of HBV, HCV, and HIV is a fundamental tool for planning and implementing health strategies in order to prevent and control viral transmission of these viral agents.Aim. To determine the seroprevalence of HBV, HCV and HIV infections in HD patients in Buenos Aires, Argentina.Methodology. Seven hundred and forty-eight HD patients were included in a retrospective cross-sectional study. Serological assays were performed to determine HBV, HCV and HIV status. HBV HBsAg and anti-HBc IgG were analysed using AxSYM (samples before 2010) or the Architect Abbott system (samples since 2010), anti-HCV IgG testing was performed using the anti-HCV enzyme immunoassay AxSYM HCV V3.0 and ARCHITECT anti-HCV, while HIV was tested for using AxSYM HIV 1/2 gO and ARCHITECT HIV Ag/Ab Combination. HCV genotyping was carried out by phylogenetic analysis of the NS5B partial gene.Results. Infection with one of the viruses was detected in 31.1 % of patients [HBV in 82 (11.0 %), HCV in 179 (23.9 %) and HIV in 6 (0.8 %)]. Thirty-two (4.3 %) patients had 2 virus markers [27 (3.6 %) with HCV/HBV, 4 (0.5 %) with HCV/HIV and 1 (0.13 %) with HBV/HIV]. Finally, a single patient (0.13 %) presented all three markers. Time on dialysis was correlated with HCV but not with HBV infection. The HCV subtype distribution in HD patients was inverted with respect to that observed in the general population (HCV-1a 73.2 % and HCV-1b 26.8 % in HD vs HCV-1a 26.5 % and HCV-1b 73.5 % in the general population, P <0.001).Conclusion. Despite the implementation of universal precautionary biosafety standards for dialysis, infection with HBV and HCV continues to occur at very high rates in HD patients. The results emphasize the need to carry out proactive tasks for early diagnosis and treatment of infected individuals and to vaccinate those with non-protective antiHBs antibodies in order to reduce morbidity and mortality in HD patients.

The first case of COVID-19 pneumonia in a hemodialysis patient in Japan

On 31 December 2019, cases of pneumonia whose cause was later identified as SARS-CoV-2 were detected in Wuhan City, Hubei Province of China, and now COVID-19 has spread worldwide. On March 1, 2020, a 69-year-old Japanese man who had been on hemodialysis for 3 years was diagnosed as having COVID-19 pneumonia and hospitalized at our Medical Center. Pulmonary CT revealed bilateral multiple consolidation with bilateral pleural effusion. Aggressive weight reduction was needed to improve the patient’s respiratory condition. Hemodialysis therapy was performed in isolation with hydroxychloroquine administration, but the formation of a dialysis membrane clot forced the withdrawal of dialysis therapy. Changing the dialysis membrane material and anticoagulant enabled the resumption of dialysis therapy, allowing the body weight to correct downward. On the 5th hospitalization day, the patient’s fever dropped and he showed improved oxygenation and chest X-ray. He was eventually discharged. The hydroxychloroquine and appropriate fluid management may have contributed to the patient’s recovery. Clinicians should pay close attention to avoid dialysis-related problems when treating a patient with COVID-19.

Prevention of acute rejection after rescue with Belatacept by association of low-dose Tacrolimus maintenance in medically complex kidney transplant recipients with early or late graft dysfunction

Background

Increased acute rejection risk in rescue protocols with Belatacept may limit its use particularly in medically complex patients where preexisting increased risk of rejection couples with CNI toxicity.

Methods

Retrospective analysis was performed in 19 KTs shifted to a Belatacept-based immunosuppression with low-dose Tacrolimus (2–3 ng/mL) after evidence of allograft disfunction, including patients with primary non-function (PNF), chronic-active antibody-mediated rejection (cAMR), history of previous KTs and/or other concomitant transplants (liver, pancreas). Evaluation of CD28⁺ CD4⁺ effector memory T cell (T_EM) before conversion was performed in 10/19.

Results

Kidney function significantly improved (median eGFR 16.5 ml/min/1.73m² before vs 25 ml/min after; p = 0.001) at a median time after conversion of 12.5 months (9.1–17.8). Overall graft and patient survival were 89.5% and 100% respectively. Definitive weaning from dialysis in 5/5 KTs with PNF was observed, whereas 7/8 patients lost their graft within first year in a control group. eGFR significantly ameliorated in re-trasplants (p = 0.001) and stabilized in KTs with other organ transplants or cAMR. No acute rejection episodes occurred, despite the significant risk suggested by high frequency of CD28⁺ CD4⁺ T_EM in most patients. Opportunistic infections were limited and most common in early vs late-converted.

Conclusions

Rescue association of Belatacept with low-dose Tacrolimus in medically complex KTs is a feasible option that allows prevention of acute rejection and amelioration of graft function.

Clinical Blood Isolates from Hemodialysis Patients: Distribution of Organisms and Antimicrobial Resistance, 2007-2014

BACKGROUND

Given the morbidity and mortality associated with bloodstream infections in hemodialysis patients, understanding the microbiology is essential to optimizing treatment in this high-risk population.

OBJECTIVES

To conduct a retrospective surveillance study of clinical blood isolates from adult hemodialysis patients, and to predict the microbiological coverage of empiric therapies for bloodstream infections in this population.

METHODS

Clinical blood isolate data were collected from the 4 main outpatient hemodialysis units in Winnipeg, Manitoba, from 2007 to 2014. The distribution of organisms and antimicrobial susceptibilities were characterized. When appropriate, changes over time were tested using time series analysis. Study data were used to predict and compare the microbiological coverage of various empiric therapies for bloodstream infections in hemodialysis patients.

RESULTS

The estimated annual number of patients receiving chronic hemodialysis increased steadily over the study period (p < 0.001), whereas the number of blood isolates increased initially, then decreased significantly, from 180 in 2011 to 93 in 2014 (p = 0.04). Gram-positive bacteria represented 72.6% (743/1024) of isolates, including Staphylococcus aureus (36.9%, 378/1024) and coagulase-negative staphylococci (23.1%, 237/1024). Only 26.1% (267/1024) of the isolates were gram-negative bacteria, the majority Enterobacteriaceae. The overall rate of methicillin resistance in S. aureus was 17.5%, and although annual rates were variable, there was a significant increase over time (p = 0.04). Antibiotic resistance in gram-negative bacteria was relatively low, except in Escherichia coli, where 13.5% and 16.2% of isolates were resistant to ceftriaxone and ciprofloxacin, respectively. Empiric therapy with vancomycin plus an agent for gram-negative coverage was predicted to cover 98.8% to 99.7% of blood isolates from hemodialysis patients, whereas cefazolin plus an agent for gram-negative coverage would cover only 67.5% to 68.4%.

CONCLUSIONS

In an era of increasing antimicrobial resistance, data such as these and ongoing surveillance are essential components of antimicrobial stewardship in the hemodialysis population.

S. aureus Colonization, Biofilm Production, and Phage Susceptibility in Peritoneal Dialysis Patients

Peritonitis caused by Staphylococcusaureus is of major importance in peritoneal dialysis (PD) patients due to its great virulence profile and biofilm formation ability. Bacteriophages are a potential tool to treat peritonitis resulting from biofilm-associated infections. We screened S. aureus colonization in 71 PD patients from the nasal cavity, groin, and PD exit-site regions and analyzed clinical outcomes in these patients. We performed biofilm-formation testing of different strains and compared the isolates of one patient to detect phenotypic differences in S. aureus. Phage cocktails were used to detect S. aureus in vitro susceptibility. An adaptation procedure was performed in cases of bacterial resistance. Around 30% of PD patients (n = 21) were found to be S. aureus carriers; from these, a total of 34 S. aureus strains were isolated, of which 61.8% (n = 21) produced a strong biofilm. Phenotypic differences in strain biofilm production were detected in eight patients out of ten. All strains were sensitive to commonly used antibiotics. Broadly positive phage lytic activity (100%) was observed in six cocktails out of seven, and bacterial resistance towards phages was overcome using adaptation. Overall phages showed a promising in vitro effect in biofilm-forming S. aureus strains.

Relapsing peritonitis and taurolidine peritoneal catheter lock: One center experience

BACKGROUND

Relapsing peritonitis due to the development of a biofilm in the catheter's lumen remains an important complication of peritoneal dialysis therapy that endangers technique continuity. Taurolidine catheter lock has proven efficient reducing infection rates in permanent hemodialysis catheters based on its biocidal activity and biofilm detachment effect. Efficacy evidence on its use in peritoneal dialysis catheters is lacking.

METHODS

We retrospectively analyzed all relapsing peritonitis episodes from June 2018 until October 2019 in our center. Patients were identified and data were collected from our electronic renal registry and patient's records.

RESULTS

Six patients were identified during the study period. Most patients (66.6%) were on automated peritoneal dialysis and the median duration of peritoneal dialysis before the episode of taurolidine was started was 43.66 ± 29.64 months. Mean taurolidine doses were 10 (range: 9-11) and 83.3% (five patients, with peritonitis caused by Pseudomonas aeruginosa, Staphylococcus aureus, Escherichia coli, and Corynebacterium propinquum) had a favorable response and microbial eradication without relapses after taurolidine treatment. Only one patient relapsed by the same organism (Corynebacterium amycolatum) due to non-adherence to the antibiotic treatment prescribed. None of the patients experienced any relevant adverse events, with only two out of six presenting mild transient abdominal discomfort.

CONCLUSION

We believe that peritoneal catheter taurolidine lock could be considered in cases of relapsing or refractory peritonitis, as it could prevent catheter removal and permanent switch to hemodialysis in selected cases, although literature is scarce and further studies are needed.

Microbiological Trends and Antimicrobial Resistance in Peritoneal Dialysis-Related Peritonitis, 2005 to 2014

Background

Information related to the microbiology of peritonitis is critical to the optimal management of patients receiving peritoneal dialysis (PD). The goal was to characterize the microbiological etiology and antimicrobial susceptibilities of PD-related peritonitis (PDRP) from 2005 to 2014, inclusive.

Methods

The distribution of organisms in culture-positive PDRP was described for new episodes and relapse infections, and further detailed for monomicrobial and polymicrobial peritonitis. Annual and overall rates of PDRP were also characterized. Antimicrobial susceptibility rates were calculated for the most common and significant organisms.

Results

We identified 539 episodes of PDRP including 501 new and 38 relapse infections. New episodes of peritonitis were associated with a single organism in 85% of cases, and 44% of those involved staphylococci. Polymicrobial PDRP was more likely to involve gram-negative organisms, observed in 58% versus 24% of monomicrobial infections. Antimicrobial resistance was relatively stable from 2005 to 2014. Methicillin resistance was present in 57% of Staphylococcus epidermidis and 20% of other coagulase-negative staphylococci. Methicillin-resistant Staphylococcus aureus (MRSA) accounted for only 11% of S. aureus peritonitis compared with 2% in our previous study of PDRP from 1991 to 1998. Ciprofloxacin resistance in Escherichia coli increased from 3% in our previous study to 24% in 2005 – 2014.

Conclusions

This study characterizes important differences in the distribution of organisms in new episodes of PDRP and relapse infections, as well as monomicrobial versus polymicrobial peritonitis. It also shows relatively stable rates of antimicrobial resistance from 2005 to 2014, but some increases compared with our previous study.

Peritoneal Microbiome in End-Stage Renal Disease Patients and the Impact of Peritoneal Dialysis Therapy

Factors influencing the occurrence of peritoneal dialysis (PD)-related infections are still far from fully understood. Recent studies described the existence of specific microbiomes in body sites previously considered microbiome-free, unravelling new microbial pathways in the human body. In the present study, we analyzed the peritoneum of end-stage kidney disease (ESKD) patients to determine if they harbored a specific microbiome and if it is altered in patients on PD therapy. We conducted a cross-sectional study where the peritoneal microbiomes from ESKD patients with intact peritoneal cavities (ESKD non-PD, n = 11) and ESKD patients undergoing PD therapy (ESKD PD, n = 9) were analyzed with a 16S rRNA approach. Peritoneal tissue of ESKD patients contained characteristically low-abundance microbiomes dominated by Proteobacteria, Firmicutes, Actinobacteria, and Bacteroidetes. Patients undergoing PD therapy presented lower species richness, with dominance by the Pseudomonadaceae and Prevotelaceae families. This study provides the first characterization of the peritoneal microbiome in ESKD patients, bringing new insight to the human microbiome. Additionally, PD therapy may induce changes in this unique microbiome. The clinical relevance of these observations should be further explored to uncover the role of the peritoneal microbiome as a key element in the onset or aggravation of infection in ESKD patients, especially those undergoing PD.

Health-Related Quality of Life in Patients with Chronic Kidney Disease in Hemodialysis in Medellín (Colombia)

PURPOSE

Hemodialysis is a treatment that is essential for the survival of patients with terminal chronic kidney disease. However, it is highly invasive, non-curative, and physically, psychologically, socially, and financially demanding, which has an impact on the patient's health-related quality of life (HRQL). In Colombia, research from the point of view of patients undergoing hemodialysis is scarce.

PATIENTS AND METHODS

We conducted a cross-sectional study involving 142 patients undergoing hemodialysis. We used an instrument that included the demographic and clinical information as well as the Charlson Comorbidity Index and Karnofsky Performance Status Scale. HRQL was assessed using EQ-5D-5L and KDQOL-36. The analysis was done using measures of central tendency for quantitative variables and relative frequencies for qualitative variables, in addition bivariate and multivariate regression analyses were conducted.

RESULTS

Based on the scores of the EQ-5D-5L scale, it was found that 14.5% subjects showed severe mobility problems, 5.8% were unable to bathe or dress by themselves, 12.9% were unable to perform usual activities, 13.5% were experiencing pain or discomfort (between strong and extreme), and 58.6% showed a certain degree of anxiety or depression. The KDQOL-36 scores were 67.4 ± 19.4 for the symptoms domain and 35.0 ± 27.5 for the disease burden domain. Results of the linear regression analysis showed that the main factors associated with HRQL were the Karnofsky Index and serum albumin levels (p < 0.05).

CONCLUSION

The result of this study revealed the impact on the quality of life of Colombian patients undergoing hemodialysis with chronic kidney disease who were highly affected by the disease burden. KDQOL-36 has excellent properties of reliability, internal consistency, and discriminant power; thus, its use is recommended in subsequent studies to monitor HRQL in this population.

Oral Colonization of Staphylococcus Species in a Peritoneal Dialysis Population: A Possible Reservoir for PD-Related Infections?

Peritoneal dialysis-related infections are important morbidity/mortality causes, being staphylococci the most prevalent agents. Since Staphylococcus aureus nasopharynx carriage is a known risk factor for PD infections and the oral cavity is a starting point for systemic diseases development, we aimed at comparing the oral staphylococci colonization between PD patients and controls and studying the association with PD-related infections. Saliva samples were plated in Mannitol salt, and isolates were identified by DnaJ gene sequencing. Staphylococci PD-related infections were recorded throughout the 4-year period following sample collection. Staphylococcus colonization was present in >90% of the samples from both groups (a total of nine species identified). PD patients presented less diversity and less prevalence of multispecies Staphylococcus colonization. Although all patients presenting Staphylococcus epidermidis PD-related infections were also colonized in the oral cavity by the same agent, only 1 out of 7 patients with ESI caused by S. aureus presented S. aureus oral colonization. Staphylococci are highly prevalent in the oral cavity of both groups, although PD patients presented less species diversity. The association between oral Staphylococcus carriage and PD-related infections was present for S. epidermidis but was almost inexistent for S. aureus, so, further studies are still necessary to evaluate the infectious potential of oral Staphylococcus carriage in PD.

DNA methylation and the potential role of demethylating agents in prevention of progressive chronic kidney disease

Chronic kidney disease (CKD) is a global epidemic, and its major risk factors include obesity and type 2 diabetes. Obesity not only promotes metabolic dysregulation and the development of diabetic kidney disease but also may independently lead to CKD by a variety of mechanisms, including endocrine and metabolic dysfunction, inflammation, oxidative stress, altered renal hemodynamics, and lipotoxicity. Deleterious renal effects of obesity can also be transmitted from one generation to the next, and it is increasingly recognized that offspring of obese mothers are predisposed to CKD. Epigenetic modifications are changes that regulate gene expression without altering the DNA sequence. Of these, DNA methylation is the most studied. Epigenetic imprints, particularly DNA methylation, are laid down during critical periods of fetal development, and they may provide a mechanism by which maternal-fetal transmission of chronic disease occurs. Our current review explores the evidence for the role of DNA methylation in the development of CKD, diabetic kidney disease, diabetes, and obesity. DNA methylation has been implicated in renal fibrosis-the final pathophysiologic pathway in the development of end-stage kidney disease-which supports the notion that demethylating agents may play a potential therapeutic role in preventing development and progression of CKD.-Larkin, B. P., Glastras, S. J., Chen, H., Pollock, C. A., Saad, S. DNA methylation and the potential role of demethylating agents in prevention of progressive chronic kidney disease.

Current Challenges and Opportunities in PD

Despite the gradual increased use of peritoneal dialysis (PD) globally around the world, it is recognized that a number of areas in PD as a renal-replacement therapy require attention and improvements. The current challenges in PD include how to tackle technique failure and sustain long-term PD, manage and prevent peritoneal infections, malnutrition and inflammation, cardiovascular mortality, volume overload, glucose exposure, adequacy of solute removal, peritoneal access, peritoneal physiology and changes with long-term PD, patient fatigue, psychosocial issues, and care of elderly patients on PD. Obviously, hemodialysis as another renal-replacement therapy modality also has its own areas that need attention and improvement by nephrologists and nurses. With more clinical and basic science research, outcome studies, and through better education and training, together with the implementation of global PD guidelines for enhancing care of PD patients, it is likely that such problem areas in PD gradually will be resolved and PD patient outcomes will be improved.

Hemodialysis versus peritoneal dialysis: an observational study in two international centers

INTRODUCTION

Given that it is difficult to randomize end-stage renal disease (ESRD) patients to either hemodialysis (HD) or peritoneal dialysis (PD), differences between these renal replacement therapy (RRT) modalities are of major interest and remain controversial.

METHODS

All data on maintenance dialysis patients during 2009 to 2013 in the Renji Hospital in Shanghai, China and in the San Bortolo Hospital in Vicenza, Italy were selected. Patients who changed their therapy from HD to PD or PD to HD during this study were excluded.

RESULTS

919 maintenance dialysis patients were included in the present study, including 509 patients on HD and 410 on PD. During the 5-year follow-up, mean arterial pressure (MAP) was higher in HD patients. The level of serum HCO3- was significantly better in PD patients than in HD patients. Phosphate was significantly higher in HD patients than in PD patients. With respect to lipid metabolism, triglyceride, total cholesterol and LDL were significantly higher in PD patients. Serum protein and albumin were higher in HD patients than in PD patients. Overall, 236 patients died (25.7%); 150 (16.3%) on HD and 86 (9.4%) on PD. The main cause of death in HD and PD patients was cerebral vascular disease and infection, respectively. After adjusting for dialysis vintage, the Kaplan-Meier patient survival was similar between HD and PD patients.

CONCLUSIONS

Based on 5 years of data, we demonstrate that lipid metabolism and nutritional status were better in HD patients. However, blood pressure control, acid-base balance, phosphate (P) control were better in PD patients. The main cause of death in HD and PD was cerebral vascular disease and infection, respectively. Considering the dialysis vintage, the Kaplan-Meier patient survival was similar between HD and PD patients.

Epidemiology and management of healthcare-associated bloodstream infections in non-neutropenic immunosuppressed patients: a review of the literature

Advancements in medicine have led to a considerable increase in the proportion of patients living with severe chronic diseases, malignancies, and HIV infections. Most of these conditions are associated with acquired immune-deficient states and treatment-related immunosuppression. Although infections as a result of neutropenia have long been recognized and strategies for management were developed, non-neutropenic immunosuppression has been overlooked. Recently, community-acquired infections in patients with frequent, significant exposure to healthcare settings and procedures have been classified as 'healthcare-associated infections' since they are more similar to hospital-acquired infections. Most of the non-neutropenic immunosuppressed patients have frequent contact with the healthcare system due to their chronic and severe diseases. In this review, we focus on the healthcare-associated bloodstream infections in the most common non-neutropenic immunosuppressive states and provide an update of the recent evidence for the management of these infections.

Cryptococcosis in HIV-negative Patients with Renal Dialysis: A Retrospective Analysis of Pooled Cases

Cryptococcosis is a lethal fungal infection mainly caused by Cryptococcus neoformans/C. gattii species. Currently, our understanding of cryptococcosis episodes in HIV-negative patients during renal dialysis remains scarce and fragmented. Here, we performed an analysis of pooled cases to systemically summarize the epidemiology and clinical characteristics of cryptococcosis among HIV-negative patients with renal dialysis. Using pooled data from our hospital and studies identified in four medical databases, 18 cases were identified and analyzed. The median duration time of renal dialysis for peritoneal renal dialysis and hemodialysis cases was 8 months and 36 months, respectively. Several non-neoformans/gattii species were identified among the renal dialysis recipients with cryptococcosis, particularly Cryptococcus laurentii and Cryptococcus albidus, which share similar clinical manifestations as those caused by C. neoformans and C. gattii. Our analyses suggest that physicians should consider the possibility of the occurrence of cryptococcosis among renal dialysis recipients even when cryptococcal antigen test result is negative. The timely removal of the catheter is crucial for peritoneal dialysis patients with cryptococcosis. In addition, there is a need for optimized antifungal treatment strategy in renal dialysis recipients with cryptococcal infections.

Comparison of topical mupirocin and gentamicin in the prevention of peritoneal dialysis-related infections: A systematic review and meta-analysis

BACKGROUND

Topical antibiotics have been shown to reduce exit-site infection and peritonitis. The aim of this study was to compare infection rates between mupirocin and gentamicin.

METHODS

Multiple comprehensive databases were searched systematically to include relevant randomized controlled trials and observational studies. Pooled risk ratios (RRs) and 95% confidence intervals were calculated for the incidences of exit-site infection and peritonitis.

RESULTS

Seven studies (mupirocin group n = 458, gentamicin group n = 448) were analyzed for exit-site infection. The risk of gram-positive exit-site infection was similar between the groups. Gram-negative exit-site infection rate was higher in the mupirocin group (RR = 2.125, P = 0.037). Six studies were assessed the peritonitis risk. There was no difference in the gram-positive and -negative peritonitis rate.

CONCLUSIONS

Topical use of gentamicin is associated with fewer exit-site infections caused by gram-negative organisms. Gentamicin has comparable efficacy to mupirocin for peritonitis and gram-positive exit-site infection.

Surface modification strategies for combating catheter-related complications: recent advances and challenges

This review summarizes the progress made in addressing bacterial colonization and other surface-related complications arising from catheter use.

Peritonitis before Peritoneal Dialysis Training: Analysis of Causative Organisms, Clinical Outcomes, Risk Factors, and Long-Term Consequences

BACKGROUND AND OBJECTIVES

Peritonitis before peritoneal dialysis (PD) training (pretraining peritonitis [PTP]) is an uncommon event. The study aim was to examine the causative organisms, clinical outcomes, risk factors, and long-term consequences of PTP.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

In this single-center, retrospective, observational study involving all incident patients on PD who developed PTP between 1998 and 2012, we examined the causative organisms, primary response rate, complete cure rate, risk factors, and associations of PTP with peritoneal equilibration test (PET) and patient survival. For each patient in the PTP group, the patients who underwent catheter insertion immediately before and after the index case were identified as controls.

RESULTS

Among 1252 incident patients on PD, 52 (4.2%) patients developed PTP, and 104 patients were identified as controls. The two groups were similar in age, sex distribution, comorbidities, and residual renal function, but the PTP group had significantly lower hemoglobin and serum albumin. Patients were followed up for a median of 37.5 months (interquartile range [IQR], 16.3-62.2 months). The most common causative organisms of PTP were Staphylococcus aureus (30.8%) and polymicrobial (21.2%); 25% had negative growth. The primary response and complete cure rates were 82.7% and 78.8%, respectively. In the PTP group, 7.7% of patients died, 9.6% of patients required catheter removal, and PD training was significantly delayed (median =42.0; IQR, 26.0-65.8 days versus 27.5; IQR, 23.0-35.0 days; P=0.01). Multivariate logistic regression analysis showed that serum albumin was the only predictor of PTP (adjusted odds ratio, 0.89 per 1-g/dl increase; 95% confidence interval, 0.82 to 0.97). There were no differences in PET results and dialysis adequacy (measured around 1 month after PD training). The PTP group had significantly worse patient survival (median =41.2; IQR, 21.8-60.5 months versus 55.8; IQR, 40.4-71.2 months; P=0.02). Technique failure occurred in 11.5% and 10.6% of patients in the PTP and control groups, respectively.

CONCLUSIONS

S. aureus is the most common causative organism of PTP. Nutritional interventions in patients who are hypoalbuminemic before catheter insertion deserve additional study.

Newer antibiotics for the treatment of peritoneal dialysis-related peritonitis

Peritonitis is a debilitating infectious complication of peritoneal dialysis (PD). Drug-resistant bacterial peritonitis typically has a lower response rate to antibiotics. In the past 15 years, newer antibiotics with activities against drug-resistant Gram-positive bacteria have been developed. In most circumstances, peritonitis due to methicillin-resistant staphylococci responds to vancomycin. If vancomycin cannot be used due to allergy and/or non-susceptibility, there is increasing evidence that linezolid and daptomycin are the drugs of choice. It is reasonable to start linezolid orally or intravenously, but subsequent dose reduction may be necessary in case of myelosuppression. Daptomycin can be given intravenously or intraperitoneally and has excellent anti-biofilm activity. Other treatment options for drug-resistant Gram-positive bacterial peritonitis include teicoplanin, tigecycline and quinupristin/dalfopristin. Teicoplanin is not available in some countries (e.g. the USA). Tigecycline can only be given intravenously. Quinupristin/dalfopristin is ineffective against Enterococcus faecalis and there is only low-quality evidence to support its efficacy in the treatment of peritonitis. Effective newer antibiotics against drug-resistant Gram-negative bacteria are lacking. Polymyxins can be considered, but evidence on its efficacy is limited. In this review, we will discuss the potential use of newer antibiotics in the treatment of drug-resistant bacterial peritonitis in PD patients.

Three-times-weekly, post-dialysis cefepime therapy in patients on maintenance hemodialysis: a retrospective study

BACKGROUND

In hemodialysis patients, post-dialysis treatment with intravenous antibiotics permits even severe infections to be managed on an outpatient basis. Cefepime is a fourth-generation cephalosporin with a broad spectrum of action in monotherapy. We report on the pharmacokinetics of cefepime in post-dialysis therapy.

METHODS

Since June 2012, twelve infections were treated with post-dialysis cefepime in 9 patients on high-flux hemodialysis. The initial post-dialysis dose of cefepime was approximately 15 mg/kg. The following doses were adapted according to the trough serum levels obtained before the subsequent dialysis in order to be above the EUCAST breakpoints for susceptible organisms and above the MIC90. Residual plasma concentrations were determined before (n = 30) and after (n = 17) dialysis by liquid chromatography-mass spectrometry.

RESULTS

Overall, the mean ± SD dose of cefepime was 920 ± 270 mg (14.5 ± 5.1 mg/kg), but it was significantly lower before the 48 h interval (775 ± 210 mg or 12.7 ± 4.5 mg/kg) compared to the 72 h interval (1125 ± 225 mg or 17.2 ± 4.9 mg/kg) (p < 0.05). The mean trough pre-dialysis concentrations were 10.7 ± 3.9 mg/l and 11.3 ± 5.6 mg/l at 48 and 72 h, respectively. These levels always largely exceeded the EUCAST susceptibility breakpoints for all the targeted bacteria (>1 mg/l) with the exception of Pseudomonas aeruginosa (>8 mg/l). Cefepime concentrations were higher in anuric patients compared to those with preserved diuresis (15.6 ± 3.5 vs 9.25 ± 3.6 mg/l; p < 0.001) and decreased on average by 81 % during dialysis (from 10.5 ± 3.7 to 1.96 ± 1.2 mg/l; p < 0.001). The clinical outcome of all patients was good.

CONCLUSIONS

Outpatient treatment with cefepime administered post-dialysis three-times-weekly was effective and well-tolerated in our patients. According to our data, in patients infected by highly susceptible pathogens a fixed dose of cefepime of 1 g before every 48-h interval and of 1.5 g before every 72-h interval should be recommended, without need of routine monitoring of the cefepime blood levels. In patients having an infection with less susceptibles pathogens as P. aeruginosa, and particularly in those among them exhibiting residual renal function, higher initial doses are necessary (1.5 g before a 48-h interval and 2.0 g before a 72-h interval) with adaption according to the subsequent pre-dialysis trough serum levels.

Peritoneal Dialysis in Asia

BACKGROUND

There is a growing demand of dialysis in Asia for end-stage renal failure patients. Diabetes mellitus is the leading cause of end-stage renal failure in many countries in Asia.

SUMMARY

The growth of peritoneal dialysis (PD) in Asia is significant and seeing a good trend. With the enhanced practices of PD, the quality of care in PD in Asia is also improved. Overall, PD and hemodialysis (HD) are comparable in clinical outcome. There is a global trend in the reduction of peritonitis rates and Asian countries also witness such improvement. The socio-economic benefits of PD for end-stage renal failure patients in both urban and rural areas in the developed and developing regions of Asia are an important consideration. This can help to reduce the financial burden of renal failure in addressing the growing demand of patients on dialysis. Initiatives should be considered to further drive down the cost of PD in Asia.

KEY MESSAGES

Growing demand for dialysis by an increasing number of end-stage renal failure patients requires the use of a cost-effective quality dialysis modality. PD is found to be comparable to HD in outcome and quality. In most countries in Asia, PD should be more cost-effective than HD. A 'PD-first' or a 'PD as first considered therapy' policy can be an overall strategy in many countries in Asia in managing renal failure patients, taking the examples of Hong Kong and Thailand.

FACTS FROM EAST AND WEST

(1) PD is cheaper than HD and provides a better quality of life worldwide, but its prevalence is significantly lower than that of HD in all countries, with the exception of Hong Kong. Allowing reimbursement of PD but not HD has permitted to increase the use of PD over HD in many Asian countries like Hong Kong, Vietnam, Taiwan, Thailand, as well as in New Zealand and Australia over the last years. In the Western world, however, HD is still promoted, and the proportion of patients treated with PD decreases. Japan remains an exception in Asia where PD penetration is very low. Lack of adequate education of practitioners and information of patients might as well be reasons for the low penetration of PD in both the East and West. (2) Patient survival of PD varies between and within countries but is globally similar to HD. (3) Peritonitis remains the main cause of morbidity in PD patients. South Asian countries face specific issues such as high tuberculosis and mycobacterial infections, which are rare in developed Asian and Western countries. The infection rate is affected by climatic and socio-economic factors and is higher in hot, humid and rural areas. (4) Nevertheless, the promotion of a PD-first policy might be beneficial particularly for remote populations in emerging countries where the end-stage renal disease rate is increasing dramatically.

Vaccine-preventable infection morbidity of patients with chronic kidney disease and cocoon vaccination strategies

Individuals with chronic kidney disease (CKD) are vulnerable to vaccine-preventable infections due to impaired immunity, immunosuppressive treatments and dialysis. Protection of CKD patients by vaccination is hampered by reduced efficacy of vaccines and safety concerns for transplant candidates or recipients. 'Cocooning' vaccination policies, targeting the protection of a vulnerable individual through immunization of close contacts, have recently been introduced for infants and, to a lesser degree, for high-risk groups of immunocompromised individuals. In this article, we discuss the potentiality of implementing cocoon strategies for the high-risk group of CKD patients and conclude that this not yet officially recommended policy can substantially contribute to protection against infection and motivate vaccination among families and healthcare workers.

Ethanol lock and risk of hemodialysis catheter infection in critically ill patients. A randomized controlled trial

RATIONALE

Ethanol rapidly eradicated experimental biofilm. Clinical studies of ethanol lock to prevent catheter-related infections (CRIs) suggest preventive efficacy. No such studies have been done in intensive care units (ICU).

OBJECTIVES

To determine whether ethanol lock decreases the risk of major CRI in patients with short-term dialysis catheters (DCs).

METHODS

A randomized, double-blind, placebo-controlled trial was performed in 16 ICUs in seven university hospitals and one general hospital in France between June 2009 and December 2011. Adults with insertion of a nontunneled, nonantimicrobial-impregnated double-lumen DC for an expected duration greater than 48 hours, to perform renal-replacement therapy or plasma exchange, were randomly allocated (1:1) to receive a 2-minute catheter lock with either 60% wt/wt ethanol solution (ethanol group) or 0.9% saline solution (control group) at the end of DC insertion and after each renal-replacement therapy or plasma exchange session. The main outcome was major CRI defined as either catheter-related clinical sepsis without bloodstream infection or catheter-related bloodstream infection during the ICU stay.

MEASUREMENTS AND MAIN RESULTS

The intent-to-treat analysis included 1,460 patients (2,172 catheters, 12,944 catheter-days, and 8,442 study locks). Median DC duration was 4 days (interquartile range, 2-8) and was similar in both groups. Major CRI incidence did not differ between the ethanol and control groups (3.83 vs. 2.64 per 1,000 catheter-days, respectively; hazard ratio, 1.55; 95% confidence interval, 0.83-2.87; P = 0.17). No significant differences occurred for catheter colonization (P = 0.57) or catheter-related bloodstream infection (P = 0.99).

CONCLUSIONS

A 2-minute ethanol lock does not decrease the frequency of infection of DCs in ICU patients. Clinical trial registered with www.clinicaltrials.gov (NCT 00875069).

High Peritoneal Glucose Exposure Is Associated with Increased Incidence of Relapsing and Recurrent Bacterial Peritonitis in Patients Undergoing Peritoneal Dialysis

Aim: We investigated the association of peritoneal glucose exposure and dialysis exchange number with peritonitis outcome in patients undergoing continuous ambulatory peritoneal dialysis (CAPD). Methods: The first episodes of bacterial peritonitis were retrospectively analyzed in 187 CAPD patients. Peritoneal glucose exposure was calculated based on PD prescription at the onset of peritonitis. Results: Patients with peritoneal glucose exposure ≤140 g/day showed a higher and complete cure rate of peritonitis (66 vs. 51.7%, p = 0.047), lower occurrence of relapsing/recurrent peritonitis (10.0 vs. 21.8%, p = 0.026) and catheter removal (14.0 vs. 26.4%, p = 0.033). Patients who exchanged more than three times every day demonstrated marginally higher catheter removal rate (24.1 vs. 13.0%, p = 0.085). Logistic analysis indicated that peritoneal glucose exposure >140 g/day was an independent predictor for relapsing/recurrent peritonitis (RR: 1.959, p = 0.042). Conclusion: High peritoneal glucose exposure is associated with increased incidence of relapsing/recurrent peritonitis in CAPD patients.

Antibacterial responses by peritoneal macrophages are enhanced following vitamin D supplementation

Patients with chronic kidney disease (CKD), who usually display low serum 25-hydroxyvitamin D (25D) and 1,25-dihydroxyvitamin D (1,25D), are at high risk of infection, notably those undergoing peritoneal dialysis (PD). We hypothesized that peritoneal macrophages from PD patients are an important target for vitamin D-induced antibacterial activity. Dialysate effluent fluid was obtained from 27 non-infected PD patients. Flow cytometry indicated that PD cells were mainly monocytic (37.9±17.7% cells CD14+/CD45+). Ex vivo analyses showed that PD cells treated with 25D (100 nM, 6 hrs) or 1,25D (5 nM, 6 hrs) induced mRNA for antibacterial cathelicidin (CAMP) but conversely suppressed mRNA for hepcidin (HAMP). PD cells from patients with peritonitis (n = 3) showed higher baseline expression of CAMP (18-fold±9, p<0.05) and HAMP (64-fold±7) relative to cells from non-infected patients. In 12 non-infected PD patients, oral supplementation with a single dose of vitamin D2 (100,000 IU) increased serum levels of 25D from 18±8 to 41±15 ng/ml (p = 0.002). This had no significant effect on PD cell CD14/CD45 expression, but mRNA for HAMP was suppressed significantly (0.5-fold, p = 0.04). Adjustment for PD cell CD14/CD45 expression using a mixed linear statistical model also revealed increased expression of CAMP (mRNA in PD cells and protein in effluent) in vitamin D-supplemented patients. These data show for the first time that vitamin D supplementation in vitro and in vivo promotes innate immune responses that may enhance macrophage antibacterial responses in patients undergoing PD. This highlights a potentially important function for vitamin D in preventing infection-related complications in CKD.

Will incremental hemodialysis preserve residual function and improve patient survival?

The progressive loss of residual renal function in peritoneal dialysis patients is associated with increased mortality. It has been suggested that incremental dialysis may help preserve residual renal function and improve patient survival. Residual renal function depends upon both patient related and dialysis associated factors. Maintaining patients in an over-hydrated state may be associated with better preservation of residual renal function but any benefit comes with a significant risk of cardiovascular consequences. Notably, it is only observational studies that have reported an association between dialysis patient survival and residual renal function; causality has not been established for dialysis patient survival. The tenuous connections between residual renal function and outcomes and between incremental hemodialysis and residual renal function should temper our enthusiasm for interventions in this area.

Use of multiplex PCR in diagnosis of bloodstream infections in kidney patients

The LightCycler® SeptiFast Test (Roche Diagnostics GmbH, Mannheim, Germany) was prospectively compared with the standard blood culture technique in a series of 86 kidney patients. The sensitivity of the PCR compared with the culture was 71%, and the specificity was 88%. All the species identified by culture in these patients were in the SeptiFast panel. The median time to results was 1 day for the PCR, 3 days for positive cultures, and 5 days for negative cultures.

Inflammation and myocardial damage markers influence loss of residual renal function in peritoneal dialysis patients

BACKGROUND

Residual renal function (RRF) has been identified as the most important component in dialysis adequacy and has a strong effect on clinical outcomes. This justifies any effort in understanding the mechanism behind the preservation or decline in RRF. The aim of this study was to analyze the possible association of components of cardio-renal syndrome with the rate of decline in RRF.

METHODS

A retrospective cohort study was performed in a group of prevalent adult patients on continuous ambulatory peritoneal dialysis (CAPD). Patients were analyzed at baseline and after a 30-month follow-up. Evaluations included measurements of residual renal function, dialysis adequacy parameters, cardiovascular comorbidity, and measurements of biochemical markers of cardiovascular disease (CVD) and inflammation, as well as resting electrocardiography.

RESULTS

We included 129 patients in the study who were divided into groups according to loss of RRF, considering the cut-off point as 100 mL/day of 24 h urine volume. At baseline, there were no differences between groups: patients who lost RRF showed low values of 24 h urine volume, higher levels of systolic blood pressure, N-terminal pro-brain natriuretic peptide (NT-proBNP), C-reactive protein (CRP), IL-6, and low values of serum albumin. In the multivariate analysis, age, albumin, CRP, and NT-proBNP were significant risk factors for the loss of RRF.

CONCLUSIONS

Data indicate a close relationship between heart and kidney function where chronic kidney disease (CKD) affects and is an effect of, heart function, indicative of a bi-directional influence that leads to a vicious cycle, promoting deleterious effects on both systems.

Streptococcus acidominimus causing invasive disease in humans: a case series

INTRODUCTION

Streptococcus acidominimus is a member of the viridans group streptococci and is rarely pathogenic in humans, making it difficult to assess its epidemiologic and clinical significance.

CASE PRESENTATION

We report the cases of five Han Chinese patients with invasive diseases caused by S. acidominimus over a one-year time frame. Three of the patients developed continuous fever after surgery, consisting of a successful elective laparoscopic cholecystectomy (case 1), a laparoscopic esophageal resection and gastroesophageal anastomosis (case 2), and a liver transplant in a patient with liver cancer (case 3). For these three patients, cultures of the purulent drainage material grew S. acidominimus. Case 4 concerns a 52-year-old man who developed sepsis 48 hours after hospitalization for hepatitis, liver cirrhosis and hepatitis-related glomerulonephritis. Case 5 concerns a 55-year-old woman receiving regular hemodialysis who had low-grade fever for one month. For these two patients, blood cultures grew S. acidominimus. An antimicrobial susceptibility test revealed that S. acidominimus was resistant to clindamycin and, to some degree, beta-lactam or macrolides. The S. acidominimus from the patient on hemodialysis was resistant to multiple antibiotics.

CONCLUSION

S. acidominimus is an ever-increasing cause of disease, especially in patients who are critically ill. It is showing increased resistance to antimicrobial agents, so in patients with viridans group streptococci infections, it is necessary to identify the species to improve the clinical management of S. acidominimus.

Occurrence of fungi in dialysis water and dialysate from eight haemodialysis units in central Italy

BACKGROUND

Fungal contamination of dialysis fluids may be a serious problem in therapy, particularly due to the debilitated immune system of haemodialysis patients.

AIM

To investigate the occurrence, distribution, and diversity of fungi in dialysis water and dialysis solution of eight haemodialysis units in a region of central Italy.

METHODS

Samples were collected over a one-year period from different points of the haemodialysis circuits in accordance with the guidelines of the Italian Society of Nephrology. Isolation and identification of fungi was performed according to the ISTISAN method Reports (2007/05 and 2008/10).

FINDINGS

Of the 976 samples analysed, 96 grew filamentous fungi, 28 were positive for yeast, and six samples contained both mould and yeast. A wide variety of filamentous fungi (26 genera, of which 15 identified at species level, and 'mycelia sterilia') were recovered, many of which are known as opportunistic pathogens. Cladosporium spp. were most frequently found (39%), followed by Alternaria spp. and Tricophyton spp. Fungal counts in treated water and standard dialysate solution were always below the threshold (<10 cfu/mL), and thus are in agreement with the Italian guidelines for dialysis fluid quality, whereas 10.9% of the samples of ultrapure dialysate solution were contaminated by one or several fungi types, in contravention of the guidelines.

CONCLUSION

The large variety of opportunistic fungi recovered in the haemodialysis circuits proves the importance of including an analysis of fungi to check the microbial quality of dialysis water and dialysate.