The Association Between Serum Vancomycin Level and Clinical Outcome in Patients With Peritoneal Dialysis Associated Peritonitis

Introduction

Intraperitoneal (IP) vancomycin is often first-line empiric therapy and then maintenance therapy for peritoneal dialysis (PD) peritonitis. However, how vancomycin serum levels correlate with clinical outcomes remains unclear.

Methods

We conducted a retrospective single-center adult cohort study of 98 patients with PD peritonitis treated with IP vancomycin between January 2016 and May 2022. The association between nadir vancomycin level and cure was evaluated in a logistic regression model, first unadjusted and then adjusted for age, sex, weight, glomerular filtration rate (GFR), and total number of days on PD. Vancomycin was assessed both as a continuous exposure (per 1 mg/l increase) and as a categorical exposure (<15 mg/l vs. ≥15 mg/l). A receiver operating characteristic curve (ROC) was created to explore nadir vancomycin level thresholds in an attempt to identify an optimal target level during treatment.

Results

Of the patients, 81% achieved cure, and patients with nadir vancomycin level ≥15 mg/l were 7.5 times more likely to experience cure compared to those with a nadir level <15 mg/l (odds ratio [OR] 7.58, 95% confidence interval [CI] 1.71-33.57, P = 0.008). Weight, GFR, days on PD, sex, and age were not independently associated with outcome. The vancomycin level with the greatest discriminatory capacity for cure on the ROC analysis was 14.4 mg/l.

Conclusion

Increasing IP vancomycin serum levels are associated with increased odds of cure; and maintaining vancomycin serum levels above 14-15 mg/l throughout the course of PD peritonitis treatment is likely to improve clinical outcomes.

Predictors of serum vancomycin levels in peritoneal dialysis-associated peritonitis

BACKGROUND

Intraperitoneal (IP) vancomycin is often first-line empiric therapy for peritoneal dialysis (PD) peritonitis; however, whether dosing should be adjusted for patient-specific characteristics remains unclear. We sought to identify factors associated with the day 3 vancomycin serum level in patients receiving vancomycin for PD peritonitis.

METHODS

Retrospective single-centre adult cohort of 58 patients with PD peritonitis treated with IP vancomycin between January 2016 and May 2022. Linear regression was used to examine the association between day 3 vancomycin level and candidate predictors including age, sex, weight, glomerular filtration rate (GFR), urea and creatinine clearance (total, residual, dialysate), PD modality, peritoneal solute transfer rate and initial vancomycin dose. Logistic regression was used to evaluate the likelihood of achieving a level (≥15 mg/L) associated with these predictor variables.

RESULTS

A 2-g loading dose was given in 51 cases, and 38 patients (66%) had a therapeutic day 3 level. Each 5 mg/kg increase in initial vancomycin dose was associated with a 1.38 mg/L (95% confidence interval 0.52, 2.23) increase in day 3 level. Each 1 mL/min increase in GFR was associated with a 0.29 mg/L decrease (95% confidence interval 0.05, 0.52) in day 3 level. The likelihood of achieving a therapeutic level was approximately four times higher with an initial dose of ≥25 mg/kg compared to <25 mg/kg (odds ratio 3.75, 95% confidence interval 1.05, 13.46).

CONCLUSIONS

Following an average 2-g vancomycin loading dose for suspected PD peritonitis, one-third of patients were subtherapeutic on day 3. GFR and weight-based dosing were independently associated with day 3 vancomycin level, and their consideration could improve the likelihood of achieving an early therapeutic level.

Clinical outcomes and adverse drug reactions in COVID-19 patients treated with hydroxychloroquine and azithromycin alone or combined

Background. Use of Hydroxychloroquine with or without Azithromycin is repurposed in SARS-CoV-2 in the absence of definitive treatment. Objective. To evaluate the association between the use of Hydroxychloroquine and Azithromycin when given alone or in combination on clinical outcomes and adverse drug reactions among lab confirmed SARS CoV-2 positive patients admitted in a COVID tertiary care hospital of a University Medical college. Methods. a retrospective observational comparative study was conducted. COVID-19 positive patients admitted in study hospital for management of COVID-19 were enrolled into the study. The patients were categorized into 4 treatment groups based on having received the following treatment during hospitalization: (A) Hydroxychloroquine with Azithromycin, (B) Hydroxychloroquine without Azithromycin (Hydroxychloroquine alone), (C) Azithromycin alone, and (D) Neither drug, defined as no receipt of either Hydroxychloroquine or Azithromycin in the record; other medications may have been dispensed. Results. 800 patients were enrolled. Mean±Standard deviation of duration of hospital stay (in days) for study Group A was 11.37±7.11, for Group B was 8.37±4.77, for Group C was 18.22 ± 5.69 and for Group D was 6.12±2.97. Mortality in Group A was 29.74%, Group B – 33.16%, Group C – 0% and in Group D – 1.32%. Conclusion. Among hospitalized patients with COVID-19 treatment, Group C was associated with good clinical outcome. However, the interpretation of these findings may be limited by the observational design.

Quality of life and well-being of population at the end of third phase of lockdown in india against the COVID-19 pandemic

Background. On March 24, 2020, a nationwide Lockdown for 21 days was ordered by the Government of India which was then extended till May 31, 2020. Researchers have predicted lockdown is a necessary step to prevent COVID-19 spread. However, others have also stated that it could cause serious damage to the economic, mental, social, and physical well-being of the people. Objective. The aim of the study is to evaluate the impact of lockdown on the quality of life and well-being of the Indians. Methods. It is a cross sectional prospective web-based questionnaire study. A link (https://forms.gle/pX25VuahP5NxT88QA) was created. Total 426 responses were received via that link and the data was included in the statistical analysis. Results. Our study revealed that during the lockdown 61.5% of the respondents were performing physical activities lesser than before. More than half responded they had a reduced financial satisfaction. Most answers on emotional well-being and social-family wellbeing were also positive, but some responses showed disturbing too, like 22% felt anxious and nervous over half of the days. It was found in the study that physical, financial, emotional, mental, social and family wellbeing were disturbed during the lockdown and quality of life was also hampered. Conclusion. Though, may be Nationwide Lockdown was the most required action at that point of time to prevent virus spread, but our study revealed that uncertainty regarding its cure and management guidelines like lockdown and social distancing has badly affected quality of life and wellbeing of the population.

Performance of the Kidney Failure Risk Equation by Disease Etiology in Advanced CKD

BACKGROUND AND OBJECTIVES

The kidney failure risk equation is a clinical tool commonly used for prediction of progression from CKD to kidney failure. The kidney failure risk equation's accuracy in advanced CKD and whether this varies by CKD etiology remains unknown. This study examined the kidney failure risk equation's discrimination and calibration at 2 and 5 years among a large tertiary care population with advanced CKD from heterogeneous etiologies.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

This retrospective cohort study included 1293 patients with advanced CKD (median eGFR 15 ml/min per 1.73 m²) referred to the Ottawa Hospital Multi-Care Kidney Clinic between 2010 and 2016, with follow-up clinical data available through 2018. Four-variable kidney failure risk equation scores for 2- and 5-year risks of progression to kidney failure (defined as dialysis or kidney transplantation) were calculated upon initial referral and correlated with the subsequent observed kidney failure incidence within these time frames. Receiver operating characteristic curves and calibration plots were used to measure the discrimination and calibration of the kidney failure risk equation both in the overall advanced CKD population and by CKD etiology: diabetic kidney disease, hypertensive nephrosclerosis, GN, polycystic kidney disease, and other. Pairwise comparisons of the receiver operating characteristic curves by CKD etiology were performed to compare kidney failure risk equation discrimination.

RESULTS

The kidney failure risk equation provided adequate to excellent discrimination in identifying patients with CKD likely to progress to kidney failure at the 2- and 5-year time points both overall (2-year area under the curve, 0.83; 95% confidence interval, 0.81 to 0.85; 5-year area under the curve, 0.81; 95% confidence interval, 0.77 to 0.84) and across CKD etiologies. The kidney failure risk equation displayed adequate calibration at the 2- and 5-year time points both overall and across CKD etiologies (Hosmer-Lemeshow P≥0.05); however, the predicted risks of kidney failure were higher than the observed risks across CKD etiologies with the exception of polycystic kidney disease.

CONCLUSIONS

The kidney failure risk equation provides adequate discrimination and calibration in advanced CKD and across CKD etiologies.

Masked Hypertension: Lessons for the Future

Masked hypertension (MH) is a commonly overlooked phenotype of hypertension in practice. Lifestyle factors and conditioned stress response specific to out of clinic blood pressure readings may be the mechanisms leading to this phenomenon. 24-hour ambulatory blood pressure monitoring or home blood pressure monitoring in an out of office setting are required for its reliable diagnosis. MH has a high risk of progressing to sustained hypertension with comparable cardiovascular and mortality risk. In this review, we discuss current evidence-based perspectives on definition, pathological mechanisms, risk factors, screening, clinical implications, and treatment of MH.

Prediction of Progression in Polycystic Kidney Disease Using the Kidney Failure Risk Equation and Ultrasound Parameters

Background

The kidney failure risk equation (KFRE) is a validated risk algorithm for predicting the risk of kidney failure in chronic kidney disease (CKD) patients regardless of etiology. Patients with autosomal dominant polycystic kidney disease (AD-PCKD) experience long disease trajectories and as such identifying individuals at risk of kidney failure would aid in intervention.

Objective

To examine the utility of the KFRE in predicting adverse kidney outcomes compared with existing risk factors in a cohort of patients with AD-PCKD.

Methods

Retrospective cohort study of AD-PCKD patients referred to a tertiary care center with a baseline kidney ultrasound and a KFRE calculation. Cox proportional hazards were used to examine the association of the KFRE and composite of an eGFR decline of >30% or the need for dialysis/transplantation. Discrimination and calibration of a parsimonious fully adjusted model and a model containing only total kidney volume (TKV) with and without the addition of the KFRE was determined.

Results

Of 340 patients with AD-PCKD eligible, 221 (65%) met inclusion criteria. Older age, cardiac disease, cancer, higher systolic blood pressure, albuminuria, lower eGFR and a higher initial TKV were more common in patients with a higher KFRE. A total of 120 events occurred over a median patient follow-up time of 3.2 years. KFRE was independently associated with the composite kidney outcome. Addition of the KFRE significantly improved discrimination and calibration in a TKV only model and a fully adjusted model.

Conclusions

In a diverse, referral population with AD-PCKD, the KFRE was associated with adverse kidney outcomes and improved risk prediction.

Successful Treatment of PD Peritonitis Due to Morganella morganii Resistant to Third-Generation Cephalosporins – A Case Report

Morganella morganii is a rare cause of peritonitis in patients on peritoneal dialysis (PD). Most of the reported cases have resorted to a switch to hemodialysis. We herein report a case of peritonitis due to M. morganii resistant to third-generation cephalosporins, which was treated successfully with intraperitoneal (IP) tobramycin followed by oral ciprofloxacin. Early microbiologic diagnosis is essential in the treatment of peritonitis from rare microorganisms such as Morganella morganii, and appropriate antibiotic therapy is the key to avoiding catheter loss and subsequent switch to hemodialysis.

Retrospective study of patients on hybrid dialysis: Single-center data from North America

Hybrid dialysis involves combining peritoneal and hemodialysis (HD) in patients with end-stage renal disease. Its reported use is quite limited outside of Japan. We present a retrospective review of 18 patients at our center that received this therapy and describe their ultimate disposition. We observed that 39% of the population on hybrid dialysis ultimately transitioned to full in center HD, 28% continue until death, and 33% either transition to home HD or received a transplant. In our center, hybrid dialysis was successful as a bridging therapy or in balancing continuation of dialysis with quality of life among those with a limited prognosis.

Characteristics and Outcomes of Exit Sites of Buried Peritoneal Dialysis Catheters: A Cohort Study

Buried peritoneal dialysis (PD) catheters are placed months before dialysis is needed and the exit site is created when the catheter is dissected out at the initiation of dialysis. In contrast, the exit site of an unburied catheter is created by the surgeon at the time of insertion. We reviewed all patients who initiated PD at our center over a 2-year period. At each clinic visit, exit sites were subjectively classified into standard predefined groups. Outcomes of interest were the frequency of perfect exit sites at 2, 6, and 12 months and rate of exit-site infections (ESIs) at 90 days. One hundred and seventy-seven patients initiated PD during the period of interest, and 169, 157, and 144 remained on PD at 2, 6, and 12 months, respectively. Ninety-three patients had buried catheters, and 76 patients had unburied catheters. Both groups had similar frequency of perfect appearance of exit sites at 2, 6, and 12 months (37/93 vs 41/76 at 2 months; 54/87 vs 43/70 at 6 months; 50/ 81 vs 35/ 63 at 12 months in buried and unburied groups, respectively). More patients with buried catheters had ESIs in the first 3 months (7/93 vs 1/76, p = 0.059). We conclude that exit sites of buried PD catheters do not differ qualitatively from those of unburied catheters. The trend towards more ESIs with buried catheters suggests that there may be clinical consequences of the tissue trauma at time of exteriorization.

End-Stage Kidney Disease in Patients With Autosomal Dominant Polycystic Kidney Disease: A 12-Year Study Based on the Canadian Organ Replacement Registry

Background:

Autosomal dominant polycystic kidney disease (ADPKD) is the most common hereditary kidney disease, with afflicted patients often progressing to end-stage kidney disease (ESKD) requiring renal replacement therapy (RRT). As the timelines to ESKD are predictable over decades, it follows that ADPKD patients should be optimized regarding kidney transplantation, home dialysis therapies, and vascular access.

Objectives:

To examine the association of kidney transplantation, dialysis modalities, and vascular access in ADPKD patients compared with a matched, non-ADPKD cohort.

Setting:

Canadian patients from 2001-2012 excluding Quebec.

Patients:

All adult incident ESKD patients who received dialysis or a kidney transplant.

Measurements:

ADPKD as defined by the treating physician.

Methods:

ADPKD and non-ADPKD patients were propensity score (PS) matched (1:4) using demographics, comorbidities, and lab values. Conditional logistic regression and Cox proportional hazards models were used to examine associations with kidney transplantation (preemptive or any), dialysis modality (peritoneal, short daily, home, or in-center hemodialysis [HD]), vascular access (arteriovenous fistula [AVF], permanent or temporary central venous catheter [CVC]), and dialysis survival.

Results:

We matched 2120 ADPKD (99.9%) with 8283 non-ADPKD with no significant imbalances between the groups. ADPKD was significantly associated with preemptive kidney transplantation (odds ratio [OR] = 7.13, 95% confidence interval [CI] = 5.74-8.87), any kidney transplant (OR = 2.37, 95% CI = 2.14-2.63), and initial therapy of nocturnal daily HD (OR = 2.74, 95% CI = 1.38-5.44), whereas in-center intermittent HD was significantly less likely in the ADPKD population (OR = 0.59, 95% CI = 0.54-0.65). There was no difference in peritoneal dialysis (PD) as initial RRT but lower use of any PD among the ADPKD group (OR = 0.85, 95% CI = 0.77-0.95). ADPKD patients were significantly more likely to have an AVF (OR = 3.25, 95% CI = 2.79-3.79) and less likely to have either a permanent (OR 0.68, 95% CI 0.59-0.78) or temporary (OR = 0.49, 95% CI = 0.41-0.59) CVC as compared with the non-ADPKD cohort. Survival on either in-center HD or PD was better for ADPKD patients (HD: hazard ratio [HR] 0.48, 95% CI 0.44-0.53; PD: HR 0.73, 95% CI 0.60-0.88).

Limitations:

Conservative care patients were not captured; despite PS matching, the possibility of residual confounding remains.

Conclusions:

ADPKD patients were more likely to receive a kidney transplant, use home HD, dialyze with an AVF, and have better survival relative to non-ADPKD patients. Conversely, they were less likely to receive PD either as initial therapy or anytime during ESKD. This may be attributed to higher transplantation or clinical decision-making processes susceptible to education and intervention.

Individual patient variability with the application of the kidney failure risk equation in advanced chronic kidney disease

The Kidney Failure Risk Equation (KFRE) predicts the need for dialysis or transplantation using age, sex, estimated glomerular filtration rate (eGFR), and urine albumin to creatinine ratio (ACR). The eGFR and ACR have known biological and analytical variability. We examined the effect of biological and analytical variability of eGFR and ACR on the 2-year KFRE predicted kidney failure probabilities using single measure and the average of repeat measures of simulated eGFR and ACR. Previously reported values for coefficient of variation (CV) for ACR and eGFR were used to calculate day to day variability. Variation was also examined with outpatient laboratory data from patients with an eGFR between 15 and 50 mL/min/1.72 m². A web application was developed to calculate and model day to day variation in risk. The biological and analytical variability related to ACR and eGFR lead to variation in the predicted probability of kidney failure. A male patient age 50, ACR 30 mg/mmol and eGFR 25, had a day to day variation in risk of 7% (KFRE point estimate: 17%, variability range 14% to 21%). The addition of inter laboratory variation due to different instrumentation increased the variability to 9% (KFRE point estimate 17%, variability range 13% to 22%). Averaging of repeated measures of eGFR and ACR significantly decreased the variability (KFRE point estimate 17%, variability range 15% to 19%). These findings were consistent when using outpatient laboratory data which showed that most patients had a KFRE 2-year risk variability of ≤ 5% (79% of patients). Approximately 13% of patients had variability from 5–10% and 8% had variability > 10%. The mean age (SD) of this cohort was 64 (15) years, 36% were females, the mean (SD) eGFR was 32 (10) ml/min/1.73m² and median (IQR) ACR was 22.7 (110). Biological and analytical variation intrinsic to the eGFR and ACR may lead to a substantial degree of variability that decreases with repeat measures. Use of a web application may help physicians and patients understand individual patient’s risk variability and communicate risk (https://mccudden.shinyapps.io/kfre_app/). The web application allows the user to alter age, gender, eGFR, ACR, CV (for both eGFR and ACR) as well as units of measurements for ACR (g/mol versus mg/g).

The Risk of Adverse Events in Patients With Polycystic Kidney Disease With Advanced Chronic Kidney Disease

Background:

Polycystic kidney disease (PKD) leads to progressive chronic kidney disease (CKD) with a subsequent risk of adverse events such as cardiac disease, infections, end-stage kidney disease (ESKD), and mortality.

Objectives:

To determine the risks of CKD-related adverse outcomes in patients with PKD compared with patients without PKD.

Setting:

Canadian study of prediction of death, dialysis and interim cardiovascular events (CanPREDDICT) was a prospective pan-Canadian cohort study from 2008-2013 involving 28 facilities with adjudicated outcomes.

Patients:

Adult CKD patients (estimated glomerular filtration rate [eGFR] = 15-45 mL/min/1.73 m²) under the care of a nephrologist.

Measurements:

Polycystic kidney disease as identified by the treating physician.

Methods:

Patients with PKD (PKD) and non-PKD were propensity score (PS) matched (1:4) using demographics, comorbidities, and laboratory values. We used conditional Cox proportional hazards models to examine the risk of cardiac disease (defined as coronary artery disease or congestive heart failure), infection, ESKD, or all-cause mortality in patients with PKD compared with no PKD.

Results:

Among a total of 2370 patients, 105 with PKD were matched with 416 without PKD with a baseline mean age and eGFR of 62.6 years and 27.8 mL/min, respectively. During 1680 person-years of follow time (median follow-up: 3.8 years), there were a total of 43 cardiac, 83 ESKD, 117 infectious, and 39 all-cause mortality events. PKD was associated with a higher risk of cardiac events (9.5% vs 7.9%, hazard ratio [HR] = 1.46, 95% confidence interval [CI] = 1.04-2.04) and ESKD (25.7% vs 13.5%, HR = 2.00, 95% CI = 1.33-3.01), and with similar risks for infection (21.9% vs 22.6%, HR = 1.16, 95% CI = 0.75-1.82) or all-cause mortality (6.7% vs 7.7%, HR = 0.87, 95% CI = 0.40-1.91) compared with non-PKD. There were no differences in the types of infections (urinary, respiratory, hematologic, or other) between the 2 groups (P = .585).

Conclusions:

Patients with PKD with advanced CKD are at a potentially higher risk of ESKD and cardiac events compared with patients without PKD. These findings, if confirmed in larger cohorts, suggest that monitoring and treatment for adverse outcomes in patients with PKD, especially related to cardiac disease, may be beneficial.

Lower serum magnesium is associated with vascular calcification in peritoneal dialysis patients: a cross sectional study

BACKGROUND

Coronary artery calcification (CAC) is highly prevalent among dialysis patients and is associated with increased cardiovascular and all cause mortality. Magnesium (Mg) inhibits vascular calcification in animal and in-vitro studies but whether the same effect occurs in humans is uncertain.

METHODS

A single centre cross-sectional study of 80 prevalent peritoneal dialysis (PD) patients; on PD only for a minimum of 3 months. A radiologist blinded to patient status calculated their abdominal aortic calcification (AAC) scores on lateral lumbar spine radiographs, a validated surrogate for CAC.

RESULTS

Eighty patients provided informed consent and underwent lumbar spine radiography. The mean serum Mg was 0.8 mmol/L (standard deviation 0.2) and mean AAC score 8.9 (minimum 0, maximum 24). A higher serum Mg level was associated with a lower AAC score (R ² = 0.06, unstandardized coefficient [B] = -7.81, p = 0.03), and remained after adjustment for age, serum phosphate, serum parathyroid hormone, low-density lipoprotein cholesterol, smoking history, and diabetes (model adjusted R ² = 0.36, serum Mg and AAC score B = -11.44, p = 0.00). This translates to a 0.1 mmol/L increase in serum Mg being independently associated with a 1.1-point decrease in AAC score.

CONCLUSIONS

Our findings suggest that Mg may inhibit vascular calcification. If this association is replicated across larger studies with serial Mg and vascular calcification measurements, interventions that increase serum Mg and their effect on vascular calcification warrant further investigation in the PD population.

Meal phosphate variability does not support fixed dose phosphate binder schedules for patients treated with peritoneal dialysis: a prospective cohort study

BACKGROUND

Removal of phosphate by peritoneal dialysis is insufficient to maintain normal serum phosphate levels such that most patients must take phosphate binders with their meals. However, phosphate 'counting' is complicated and many patients are simply prescribed a specific dose of phosphate binders with each meal. Therefore, our primary objective was to assess the variability in meal phosphate content to determine the appropriateness of this approach.

METHODS

In this prospective cohort study, adult patients with ESRD treated with peritoneal dialysis and prescribed phosphate binder therapy were eligible to participate. Participants were excluded from the study if they were unable to give consent, had hypercalcemia, were visually or hearing impaired or were expected to receive a renal transplant during the time of the study. After providing informed consent, patients kept a 3-day diet diary that included all foods and beverages consumed in addition to portion sizes. At the same time, patients documented the amount of phosphate binders taken with each meal. The phosphate content of the each meal was estimated using ESHA Food Processor SQL Software by a registered dietitian. Meal phosphate and binder variability were estimated by the Intra Class Correlation Coefficient (ICC) where 0 indicates maximal variability and 1 indicates no variability.

RESULTS

Seventy-eight patients consented to participate in the study; 18 did not complete the study protocol. The patients were 60 (± 17) years, predominately male (38/60) and Caucasian (51/60). Diabetic nephropathy was the most common cause of end stage kidney disease. The daily phosphate intake including snacks ranged from 959 ± 249 to 1144 ± 362 mg. The phosphate ICC by meal: breakfast 0.63, lunch 0.16; supper 0.27. The phosphate binder ICC by meal: breakfast 0.68, lunch 0.73, supper 0.67.

CONCLUSION

The standard prescription of a set number of phosphate binders with each meal is not supported by the data; patients do not appear to be adjusting their binders to match the meal phosphate content. An easy to use phosphate counting program that assists the patient in determining the appropriate amount of phosphate binder to take may enhance phosphate control.

Fluoroscopic manipulation of peritoneal dialysis catheters: outcomes and factors associated with successful manipulation

BACKGROUND AND OBJECTIVES

Mechanical failure of the peritoneal dialysis (PD) catheter is an important cause of technique failure. Fluoroscopic guidewire manipulation may be undertaken in an attempt to correct the failure. The purpose of this study was to determine the efficacy of fluoroscopic manipulation of previously embedded PD catheters, the factors associated with successful manipulation, and the complication rate associated with manipulation.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

A single-center, retrospective review of 70 consecutive PD patients undergoing fluoroscopic manipulation for mechanical failure of their PD catheter from June 2006 to February 2011 was undertaken. Logistic regression models were developed to determine the variables associated with successful manipulation.

RESULTS

Of the 70 manipulations, 44 were successful (62.9%). In univariate analysis, catheters located in the pelvis compared with those in the upper abdomen (73.5% versus 42.9%, P=0.01) and catheters that were previously functional compared with those that failed at exteriorization (75.0% versus 46.7%, P=0.04) were more likely to be successfully manipulated. Time embedded, previous hemodialysis, and number of intra-abdominal surgeries were not correlated with likelihood of successful manipulation. In multivariate analysis, catheters located in the pelvis (P=0.01) and those with secondary failure (P=0.01) were more likely to successfully manipulated. Two of the patients developed peritonitis (2.9%), neither requiring cessation of PD.

CONCLUSIONS

Fluoroscopic manipulation is an effective and safe therapy for failed PD catheters that are unresponsive to conservative treatment. Properly positioned catheters and those that were previously functional are more likely to be successfully manipulated.

Hypercreatinemia: think beyond acute kidney injury

Urinary bladder rupture associated with severe hypercreatinemia is a rare clinical presentation. We herein report a 60-year-old interesting patient who was found to have intraperitoneal bladder rupture and pseudo-renal failure. High rate of suspicion and timely diagnosis is the key in management of this condition, which led to complete recovery in our patient.

Vancomycin nephrotoxicity: myths and facts

Vancomycin is a key antibiotic in the management of severe Gram-positive infections. Recent emergence of methicillin-resistant staphylococcal strains with reduced susceptibility to vancomycin has prompted internists to administer high-dose treatment to achieve trough levels of 15 to 20 mg/l. Such high doses might be causative in nephrotoxicity. The risk further increases in patients who are critically ill and are on vasopressor support and/or concomitant nephrotoxic agents, with baseline deranged renal function, undergoing prolonged duration of therapy and are obese. However, data are insufficient to recommend the superiority of continuous infusion regimens as compared with intermittent dosing. This review discusses the literature pertaining to vancomycin nephrotoxicity.

Renal cocktail: too hard for a diabetic

We herein report a case of a 67-year-old diabetic woman who presented with a history of fatigue for 1 month. Her investigations showed proteinuria, active urine sediment, p-ANCA positivity and worsened renal functions. A diagnosis of rapidly progressive glomerulonephritis was made. Renal biopsy revealed class V (membranous) lupus nephritis with superimposed ANCA-associated crescentic glomerulonephritis. She was treated with steroids and cyclophosphamide. Two months later, she presented with cytomegalovirus colitis and deep vein thrombosis of right leg. The case reflects an interesting renal pathology, and complications of the disease per se and its treatment.

Angiotensin-Converting Enzyme Inhibitors and Angiotensin Receptor Blockers in Peritoneal Dialysis: Systematic Review and Meta-Analysis of Randomized Controlled Trials

Background

Angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs) are widely used in clinical practice. The safety and efficacy of these agents in peritoneal dialysis (PD) patients are unclear.

Objectives

We conducted a systematic review to study the safety and efficacy of ACEI and ARB use in PD patients. Primary outcome measures were mortality and cardiovascular (CV) events; secondary outcome measures were renal function, proteinuria, hyperkalemia, and erythropoietin requirement at 3 months.

Methods

We searched Medline, EMBASE, Cochrane Central Register of Controlled Trials, trial registry Web sites, reference lists of eligible and review articles, as well as abstracts from the American Society of Nephrology and Canadian Society of Nephrology meetings. To be eligible, studies had to be randomized controlled trials that allocated PD patients to ACEI and ARB use or to placebo or other antihypertensive medications, included adult patients, and reported on at least one of the outcome measures.

Results

418 citations were identified. Four met the eligibility criteria. Three examined CV events and mortality, of which two studies did not have any events. The third showed no statistically significant difference between control and treatment groups in either CV events or mortality: odds ratio 1.56 [95% confidence interval (CI) 0.24 – 10.05] for mortality and odds ratio 1.00 (95% CI 0.19 – 5.40) for CV events. Two studies reported renal function at 12 months and the weighted mean difference was 0.91 mL/minute/1.73 m2 (95% CI 0.14 – 1.68), favoring ACEI and ARB use.

Conclusions

In PD patients, evidence for the use of ACEIs and ARBs for reduction of mortality and CV events is lacking. Limited data suggest that they slow the loss of residual renal function.

Angiotensin-converting enzyme inhibitors and angiotensin receptor blockers in peritoneal dialysis: systematic review and meta-analysis of randomized controlled trials

BACKGROUND

Angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs) are widely used in clinical practice. The safety and efficacy of these agents in peritoneal dialysis (PD) patients are unclear.

OBJECTIVES

We conducted a systematic review to study the safety and efficacy of ACEI and ARB use in PD patients. Primary outcome measures were mortality and cardiovascular (CV) events; secondary outcome measures were renal function, proteinuria, hyperkalemia, and erythropoietin requirement at 3 months.

METHODS

We searched Medline, EMBASE, Cochrane Central Register of Controlled Trials, trial registry Web sites, reference lists of eligible and review articles, as well as abstracts from the American Society of Nephrology and Canadian Society of Nephrology meetings. To be eligible, studies had to be randomized controlled trials that allocated PD patients to ACEI and ARB use or to placebo or other antihypertensive medications, included adult patients, and reported on at least one of the outcome measures.

RESULTS

418 citations were identified. Four met the eligibility criteria. Three examined CV events and mortality, of which two studies did not have any events. The third showed no statistically significant difference between control and treatment groups in either CV events or mortality: odds ratio 1.56 [95% confidence interval (CI) 0.24 - 10.05] for mortality and odds ratio 1.00 (95% CI 0.19 - 5.40) for CV events. Two studies reported renal function at 12 months and the weighted mean difference was 0.91 mL/minute/1.73 m(2) (95% CI 0.14 - 1.68), favoring ACEI and ARB use.

CONCLUSIONS

In PD patients, evidence for the use of ACEIs and ARBs for reduction of mortality and CV events is lacking. Limited data suggest that they slow the loss of residual renal function.

Use of the embedded peritoneal dialysis catheter: Experience and results from a North American Center

Since 2000, the Ottawa Hospital Home Dialysis Program has used a variation on the embedded peritoneal dialysis catheter technique described by Moncrief et al. In this paper, we describe our approach to placement of peritoneal access and report our experience with 304 embedded catheters placed between January 2000 and December 2003. We review the advantages and disadvantages of this technique and describe factors that have been important to the success of our program.

Technique survival with Serratia peritonitis

Despite a decreasing incidence, peritonitis remains an important cause of peritoneal dialysis (PD) technique failure and transfer to hemodialysis. Infection with Serratia spp. has been suggested to be associated with a poor technique outcome in PD. We examined the data at our center to see if patients with Serratia peritonitis had a similar poor outcome. In this retrospective study, we reviewed all PD patients who presented at our center with peritonitis from January 1996 to December 2003. The case records of patients in whom the infecting organism was identified as Serratia were evaluated. We recorded age at the time of peritonitis and at the start of PD, sex, presence of diabetes mellitus, PD modality at the time of peritonitis, and duration of PD before the onset of peritonitis. For each episode of peritonitis, we recorded the type and duration of antibiotic therapy and the outcome. Over the study period, 52% of all peritonitis episodes involved gram-positive organisms; 29%, gram-negative organisms; and 19%, other organisms. Serratia spp. accounted for 16 episodes (3.68%). These 16 episodes of peritonitis occurred in 12 patients, with 3 repeat infections and 1 relapsing infection. The distribution between the sexes was equal, and the median age at diagnosis was 67 years (range: 37-79 years). Four patients with diabetes accounted for 6 of the 16 episodes (37.5%). In 7 episodes (43.8%), a Serratia exit-site infection preceded the peritonitis. In 4 episodes, catheter removal was required. A fifth patient developed sepsis and died. Technique survival was therefore 68.8% (11 of 16 episodes). We also compared the outcomes of different initial antibiotic regimens. With an initial regimen based on cefazolin-ceftazidime, as suggested in the 2000 guidelines of the International Society for Peritoneal Dialysis, technique survival was 60% (3 of 5 episodes). When the initial regimen included an aminoglycoside, the technique survival was 80% (8 of 10 episodes). Serratia-induced peritonitis was associated with a technique survival of 68.8% at our center.

Immunomodulatory activity of boswellic acids of Boswellia serrata Roxb

Extract of gum resin of B. serrata containing 60% acetyl 11-keto beta boswellic acid (AKBA) along with other constituents such as 11-keto beta-boswellic acid (KBA), acetyl beta-boswellic acid and beta-boswellic acid has been evaluated for antianaphylactic and mast cell stabilizing activity using passive paw anaphylaxis and compound 48/80 induced degranulation of mast cell methods. The extract inhibited the passive paw anaphylaxis reaction in rats in dose-dependant manner (20, 40 and 80 mg/kg, po). However, the standard dexamethasone (0.27 mg/kg, po) revealed maximum inhibition of edema as compared to the extract. A significant inhibition in the compound 48/80 induced degranulation of mast cells in dose-dependant manner (20, 40 and 80 mg/kg, po) was observed thus showing mast cell stabilizing activity. The standard disodium cromoglycate (50 mg/kg, ip) was found to demonstrate maximum per cent protection against degranulation as compared to the extract containing 60% AKBA. The results suggest promising antianaphylactic and mast cell stabilizing activity of the extract.

Hundredfold productivity of genome analysis by introduction of microtemperature-gradient gel electrophoresis

Genome profiling, which employs temperature-gradient gel electrophoresis (TGGE) for DNA analysis, has recently been developed in identifying species by genotype. However, the performance of this technology like the general applications of TGGE was, though highly informative, limited in its ability due to methodological reasons. This study demonstrates that minimization of the gel for TGGE, to around one-tenth of its conventional size (approximately 2 cm), can be successfully introduced, resulting in a hundredfold higher performance (total evaluation of time, cost, and degree of parallel operations) than that of the conventional. Reproducibility was evaluated from the measures of the pattern similarity scores (PaSS) between band patterns (genome profiles) obtained with the conventional TGGE, and that with micro-TGGE (microTGGE) developed here, after extracting a set of featuring points from genome profiles. Size minimization, which leads to the reduction of the amount of samples required (cost-saving), is another great advantage, enhancing the employment of multicolor fluorescence technology. Since the further development of microbe-related fields such as epidemiology and microbial ecology inevitably require knowledge based on the identification of a great number of species and strains, microbe-related fields will receive the most optimal benefits from the technological improvements attained here.