Outcomes of Acinetobacter Peritonitis in Peritoneal Dialysis Patients: A Multicenter Registry Analysis

Rescue plan for CAPD peritonitis: Using ultrasonography as a guide on when to remove the catheter

INTRODUCTION

Ultrasound has been found to facilitate early identification of peritonitis in patients undergoing continuous ambulatory peritoneal dialysis (CAPD).

METHODS

A retrospective analysis was carried out to evaluate the effectiveness of ultrasonography-guided removal of the Tenckhoff catheter in reducing complications like a shift to hemodialysis or death in CAPD patients.

RESULTS

The "peritonitis rescue plan" supported timely decision-making for the removal of the infected catheter and resulted in a lower peritonitis episode per patient per month ratio (from 1:36 to 1:122) in 2021, a lower death rate (from 19% to 6.6%) and lower incidences of shifts to hemodialysis (from 2%-9% to 0%) as compared to that before the implementation of the plan in 2019.

CONCLUSION

The implementation of the "peritonitis rescue plan" and the removal of the infected catheter within 3 days of peritonitis being detected was successful in improving the standard of care for patients undergoing CAPD.

ISPD peritonitis guideline recommendations: 2022 update on prevention and treatment

Peritoneal dialysis (PD)-associated peritonitis is a serious complication of PD and prevention and treatment of such is important in reducing patient morbidity and mortality. The ISPD 2022 updated recommendations have revised and clarified definitions for refractory peritonitis, relapsing peritonitis, peritonitis-associated catheter removal, PD-associated haemodialysis transfer, peritonitis-associated death and peritonitis-associated hospitalisation. New peritonitis categories and outcomes including pre-PD peritonitis, enteric peritonitis, catheter-related peritonitis and medical cure are defined. The new targets recommended for overall peritonitis rate should be no more than 0.40 episodes per year at risk and the percentage of patients free of peritonitis per unit time should be targeted at >80% per year. Revised recommendations regarding management of contamination of PD systems, antibiotic prophylaxis for invasive procedures and PD training and reassessment are included. New recommendations regarding management of modifiable peritonitis risk factors like domestic pets, hypokalaemia and histamine-2 receptor antagonists are highlighted. Updated recommendations regarding empirical antibiotic selection and dosage of antibiotics and also treatment of peritonitis due to specific microorganisms are made with new recommendation regarding adjunctive oral N-acetylcysteine therapy for mitigating aminoglycoside ototoxicity. Areas for future research in prevention and treatment of PD-related peritonitis are suggested.

A Comparison of Production Performance, Egg Quality, and Cecal Microbiota in Laying Hens Receiving Graded Levels of Vitamin B12

The objective of the study was to investigate the effect of fortified diets with standard vs. high levels of vitamin B₁₂ on cecal microbiota composition, production performance, and eggshell quality of laying hens. Dietary treatments consisted of a basal diet with no supplementation of vitamin B₁₂ or supplemented with 25, 100, and 400 μg/kg vitamin B₁₂, respectively. A total of 432 laying hens were randomly assigned to four treatments with six replicates per treatment. No significant effect of dietary treatments on the production performance of hens was detected. The shell thickness of eggs from hens fed diet supplemented with 100 μg/kg of vitamin B₁₂ was higher (P < 0.01) than that of eggs from hens fed control diet or supplemented with 25 μg/kg vitamin B₁₂. The shell percentage of eggs from hens fed diet supplemented with 400 μg/kg of vitamin B₁₂ was higher (P < 0.01) than that of eggs from hens fed other treatment diets. Dietary vitamin B₁₂ did not modulate diversity of the cecal microbiota of the layers. At genus level, the cecal content from layers fed diet with supplemental level of 100 or 400 μg/kg of vitamin B₁₂ had higher (P < 0.01) abundance of Faecalibacterium and lower (P < 0.05) abundance of Acinetobacter compared with the cecal content from layers fed other two diets. The abundance of Lactobacillus in the cecal samples from layers fed 100 μg/kg of supplemental level of vitamin B₁₂ was higher (P < 0.05) than that from layers fed other three diets. The abundance of Butyricicoccus was higher (P < 0.05), while Bilophila was lower (P < 0.05) in the cecal content of layers fed 400 μg/kg of vitamin B₁₂ diet compared with those from layers fed other three diets. The results of PICRUSt analysis indicated that 10 predicted metabolic functions of the cecal microbial communities were positively correlated to dietary vitamin B₁₂ level. Overall, dietary supplementation of 100 or 400 μg/kg of vitamin B₁₂ had equivalent effects and caused the significant change in composition and metabolic functions of cecal microorganisms, which could positively impact eggshell quality, metabolism, and gut health of laying hens.

Interaction of Staphylococcus aureus and Acinetobacter baumannii during In Vitro β-Lactam Exposure

We sought to determine if Acinetobacter baumannii is capable of altering the pharmacodynamics of an antistaphylococcal β-lactam. Two strains of methicillin-susceptible Staphylococcus aureus (MSSA) and two A. baumannii isolates were studied in 24-h static time-killing experiments under monoculture or coculture conditions. Bacterial killing of meropenem was described using an empirical pharmacokinetics/pharmacodynamics model that was developed using Hill functions. A mechanism-based pharmacodynamic model was also used to describe the effect of meropenem on each species of bacterium, interspecies interactions, and strain-based covariate effects. Monte Carlo simulations of bacterial killing effects were generated based on the population pharmacokinetics of meropenem in 2,500 simulated critically ill subjects over 48 h. Against one of the two MSSA isolates, the magnitude of bacterial killing (E _Δ) decreased from -4.61 (95% confidence interval [CI], -5.85 to -3.38) to -2.23 (95% CI, -2.85 to -1.61) when cultured in the presence of carbapenem-resistant A. baumannii (CRAB). Similarly, the data were best described by a mechanism-based model where the number of A. baumannii cells produced a systematic increase in the S. aureus concentration for a 50% maximum killing effect (KC₅₀) of 3.53-fold, thereby decreasing MSSA sensitivity to meropenem. A covariate effect by the CRAB isolate resulted in a more pronounced increase in the MSSA KC₅₀ for meropenem (31.8-fold increase). However, Monte Carlo simulations demonstrated that a high-intensity meropenem regimen is capable of sustained killing against both MSSA isolates despite protection from A. baumannii Thus, A. baumannii and MSSA engage in complex interactions during β-lactam exposure, but optimal antimicrobial dosing is likely capable of killing MSSA despite the potentially beneficial interplay with A. baumannii.

Multicentre registry data analysis comparing outcomes of culture-negative peritonitis and different subtypes of culture-positive peritonitis in peritoneal dialysis patients

BACKGROUND

The outcomes of culture-negative peritonitis in peritoneal dialysis (PD) patients have been reported to be superior to those of culture-positive peritonitis. The current study aimed to examine whether this observation also applied to different subtypes of culture-positive peritonitis.

METHODS

This multicentre registry study included all episodes of peritonitis in adult PD patients in Australia between 2004 and 2014. The primary outcome was medical cure. Secondary outcomes were catheter removal, hemodialysis transfer, relapsing/recurrent peritonitis and peritonitis-related death. These outcomes were analyzed using mixed effects logistic regression.

RESULTS

Overall, 11,122 episodes of peritonitis occurring in 5367 patients were included. A total of 1760 (16%) episodes were culture-negative, of which 77% were medically cured. Compared with culture-negative peritonitis, the odds of medical cure were lower in peritonitis caused by Staphylococcus aureus (adjusted odds ratio (OR) 0.62, 95% confidence interval (CI) 0.52-0.73), Pseudomonas species (OR 0.20, 95% CI 0.16-0.26), other gram-negative organisms (OR 0.48, 95% CI 0.41-0.56), polymicrobial organisms (OR 0.30, 95% CI 0.25-0.35), fungi (OR 0.02, 95% CI 0.01-0.03), and other organisms (OR 0.61, 95% CI 0.49-0.76), while the odds were similar in other (non-staphylococcal) gram-positive organisms (OR 1.11, 95% CI 0.97-1.28). Similar results were observed for catheter removal and hemodialysis transfer. Compared with culture-negative peritonitis, peritonitis-related mortality was significantly higher in culture-positive peritonitis except that due to other gram-positive organisms. There was no difference in the odds of relapsing/recurrent peritonitis between culture-negative and culture-positive peritonitis.

CONCLUSION

Culture-negative peritonitis had superior outcomes compared to culture-positive peritonitis except for non-staphylococcal gram-positive peritonitis.

Longer antibiotic durations for treating peritoneal dialysis-associated peritonitis: helpful or harmful?

Relapsing, recurrent or repeat peritonitis is a devastating complication for peritoneal dialysis (PD) patients and is usually associated with poor outcomes including prolonged hospitalization, catheter removal, hemodialysis transfer and even death. Despite its critical importance and frequent occurrence, there is limited available evidence to facilitate evidence-informed treatment of PD peritonitis. This editorial comments on the findings and limitations of a randomized controlled study published in this journal, which reported that extending antibiotic treatment duration for an additional week beyond that recommended by the International Society for PD did not reduce the risk of relapsing, recurrent or repeat peritonitis, and may have increased the risk of repeat peritonitis. These results are explored in the context of the existing literature and recommendations for practice and research are provided.

Chlorhexidine-impregnated sponge dressing for prevention of catheter exit-site infection in peritoneal dialysis patients: a pilot study

PURPOSE

The study aimed to examine effect of chlorhexidine dressing in the prevention of peritoneal dialysis (PD)-related infection in PD patients.

METHODS

This single-center pilot study recruited 50 incident PD patients to use weekly chlorhexidine dressing. The primary outcome was exit-site/tunnel infection rate. Secondary outcomes were peritonitis rate, time to first PD-related infection, infection-related hospitalization, technique and patient survival, adverse events, and chlorhexidine dressing acceptability. These clinical outcomes were compared with those of a historical cohort (2016-2017) using daily gentamicin cream.

RESULTS

A total of 50 patients were recruited to use chlorhexidine and followed up for one year. The exit-site/tunnel infection rate was 0.09 (95% confidence interval [CI] 0.02-0.22) and peritonitis rate was 0.07 (95% CI 0.01-0.19) episodes per patient-year with chlorhexidine dressing. The 1-year infection-free survival rates for exit-site/tunnel infection and peritonitis were 92% and 94%, respectively. The 1-year technique and patient survival rates were 86% and 96%, respectively. Overall, 12% of participants developed localized contact dermatitis with chlorhexidine. Most participants (73%) reported that chlorhexidine dressings were very acceptable. Compared to a historical cohort using gentamicin cream (n = 238), the chlorhexidine group had similar exit-site/tunnel infection rates (incidence rate ratio [IRR] 0.65, 95% CI 0.22-1.92) but had lower peritonitis rates (IRR 0.24, 95% CI 0.07-0.77), and lower PD infection-related hospitalization rates (IRR 0.21, 95% CI 0.06-0.69) after adjusting for age, sex, race, primary kidney disease, and diabetes mellitus.

CONCLUSION

Weekly chlorhexidine dressing was associated with acceptable PD-related infection outcomes and was well-accepted by patients, although had a 12% rate of delayed localized contact dermatitis.

TRIAL REGISTRATION NUMBER AND DATE

The study was registered under www.clinicaltrials.gov with the reference number of NCT03406520 on 23 January 2018.

Comparison of Clinical Presentation and Outcomes of Peritonitis in the Elderly and Younger Peritoneal Dialysis Patients

Background

The incidence of elderly patients receiving peritoneal dialysis (PD) has increased. This study aimed to examine the clinical presentation and outcomes of peritonitis in elderly PD patients compared with younger PD patients.

Methods

This single-center, retrospective, observational cohort study included all adult PD patients who developed peritonitis between January 2011 and December 2014. Elderly was defined as ≥ 65 years old at PD initiation. The primary outcome was medical cure, defined as a peritonitis episode cured by antibiotics without being complicated by catheter removal, transfer to hemodialysis (HD), relapsing peritonitis, or death. The secondary outcomes were clinical manifestations (fever, cloudy dialysate) and complications (catheter removal, transfer to HD, relapse, hospitalization, and mortality). Peritonitis outcomes were compared using multivariable logistic regression.

Results

Overall, 377 peritonitis episodes occurred in 247 patients. Of these, 126 episodes occurred in 79 elderly patients and 251 episodes occurred in 168 younger patients. Baseline demographic data were comparable between the 2 groups, except that elderly patients were significantly more likely to have diabetes mellitus (66% vs 46%), diabetic nephropathy (55% vs 39%), and a lower serum albumin than younger patients. Medical cure was comparable between the 2 groups (71% vs 72%, respectively, p = 0.67, adjusted odds ratio [AOR] 0.89, 95% confidence interval [CI]: 0.52 – 1.53). Compared with younger patients, elderly patients experiencing peritonitis had lower odds of fever (OR 0.53, 95% CI: 0.30 – 0.94), cloudy dialysate (OR 0.45, 95% CI: 0.23 – 0.88), and catheter removal (AOR 0.50, 95% CI: 0.26 – 0.98), but similar odds of transfer to HD (AOR 0.70, 95% CI: 0.32 – 1.51), relapse (AOR 1.57, 95% CI: 0.46 – 5.40), hospitalization (AOR 1.55, 95% CI: 0.52 – 4.56), and all-cause mortality (AOR 1.88, 95% CI: 0.83 – 4.26).

Conclusions

Compared with younger patients, elderly PD patients with peritonitis achieved similar medical cure rates, a lower catheter removal rate, and comparable rates of HD transfer, relapse, hospitalization, and death. Elderly PD patients experiencing peritonitis were less likely to present with fever or cloudy dialysate.

A Case of Relapsing Peritoneal Dialysis-Associated Peritonitis by Dokdonella koreensis

Peritonitis is a common and serious complication of peritoneal dialysis (PD) with significant morbidity. We report the first case of relapsing Dokdonella koreensis peritonitis in a patient on peritoneal dialysis. A 63-year-old Chinese man, with history of renal failure on continuous ambulatory peritoneal dialysis, presented with cloudy peritoneal effluent and abdominal pain. There was no sign or symptom suggestive of exit-site/tunnel tract infection. Peritoneal effluent cultures yielded Dokdonella koreensis which was initially misidentified as Weeksella virosa and Brevundimonas species by the API® 20 NE and VITEK® 2 GN ID card, respectively. He was treated with intraperitoneal amikacin, but the infection relapsed within a few days upon completing each antibiotic course. He eventually required removal of catheter and was transferred to hemodialysis. Infections due to unusual organisms may pose a diagnostic issue as currently available commercial tests will not be able to identify them. There is a role for using 16S rRNA sequencing to help identify these organisms and guide patient management.