Exit site infection and peritonitis due to Serratia species in patients receiving peritoneal dialysis: Epidemiology and clinical outcomes.

AIM: To study the epidemiology and clinical outcomes of catheter-related infections of Serratia species in peritoneal dialysis (PD) patients. METHODS: We retrospectively reviewed the patient characteristics, antibiotics susceptibility/resistance patterns and treatment outcomes of exit site infection (ESI) and peritonitis due to Serratia in PD patients during the period of 2004 to 2017. RESULTS: One hundred and sixty-one patients had Serratia ESI, of which 10 (6.2%) progressed to tunnel tract involvement and 11 (6.8%) developed PD peritonitis. Nineteen (11.8%) patients with Serratia ESI failed to respond to medical treatment and required catheter removal. Fifty-six (34.8%) patients had repeat Serratia ESI, which occurred at 12.9 ± 13.6 months after the previous episode. Twenty-two patients had Serratia peritonitis, which accounted for 1% of peritonitis during the study period. Ten (45.5%) patients responded to medical treatment while 12 (54.5%) patients required catheter removal. Nine patients (36.4%) failed to resume PD and were converted to long-term haemodialysis. Two patients had repeat peritonitis at 2 months and 3 years, respectively, after the initial episode. Serratia species in PD patients showed high rates of resistance to ampicillin, and first- and second-generation cephalosporins, but were generally susceptible to aminoglycosides, carboxy-/ureido-penicillins and carbapenems. CONCLUSION: Our results suggest that Serratia ESI show low risk of progression to peritonitis and favourable response to medical therapy, while Serratia peritonitis was associated with high rates of catheter removal and peritoneal failure.

Prevalence of CMMSE defined cognitive impairment among peritoneal dialysis patients and its impact on peritonitis.

BACKGROUND: Peritoneal dialysis (PD) exchange procedure is complex. Patients with cognitive impairment (CI) may require assistance. We studied the prevalence of CI among PD patients, its impact on PD-related peritonitis and the outcome of assisted PD. METHODS: Cantonese version of Mini-Mental State examination (CMMSE) was performed in 151 patients newly started on PD. Data on patient characteristics including demographics, co-morbidities, blood parameters, medications, and number of PD-related peritonitis in the first 6 months were collected. RESULTS: 151 subjects were recruited. The age of studied patients was 60 ± 15.0 years, and 45% were female. The prevalence of CI was 13.9% using education-adjusted cut-off of CMMSE. Patients older than 65-year-old, female, and lower education level were independent risk factors for CI (OR 9.27 p = 0.001, OR 14.84 p = 0.005, and OR 6.10 p = 0.009, respectively). Age greater than 65-year old is an independent risk factor for PD-related peritonitis but CI was not. Patients requiring assisted PD were of older age (p < 0.001), lower CMMSE (p < 0.001), and scored higher for age-adjusted Charlson Co-morbidity index (p < 0.001). Compared with self-care PD patients, assisted PD patients did not have higher rates exit site infection (p = 0.30) but had a trend of higher PD peritonitis (p = 0.07). CONCLUSION: CI is common among local PD patients. Overall, CI could not be identified as an independent risk factor for PD peritonitis. There is a higher prevalence of CI among assisted PD patients but helpers may not completely eliminate the risk of PD-related peritonitis.

Charlson co-morbidity index and albumin significantly associated with fracture risk in peritoneal dialysis patients.

Published literature on fracture in dialysis patients seldom addressed the effect of co-morbidity and malnutrition. In this study, we reported the incidence and risk factors for fracture in peritoneal dialysis patients. Peritoneal dialysis patients who had fractures between 2006 and 2011 were recruited. Demographic data, details of fracture, Charlson Co-morbidity Index (CCI) and biochemical parameters were also collected. Non-fracture controls, matched for age, gender and duration of dialysis, were also recruited at ratio 1:1 for fracture risk analysis. The incidence of fracture was 1 in 37 patient-years. The commonest site of fracture was neck of femur (n = 16, 55.2%). Twenty-four patients (82.8%) developed fracture after slip and fall injury. Eight out of 17 self-ambulatory patients (47.1%) became non-ambulatory after fracture. Infection was the commonest complication during hospitalization. Univariant analysis demonstrated high CCI (P = 0.001), hypoalbuminaemia (P < 0.001), loss of self autonomy (P = 0.006) and non-ambulatory state (P = 0.011) significantly associated with increased fracture risk. However, only CCI (odds ratio (OR) 1.373, P = 0.028) and albumin (OR 0.893, P = 0.025) increased fracture risk significantly on multivariant analysis. Bone profile and parathyroid hormone were not significant risk factors. To conclude, fracture associated with adverse outcome in peritoneal dialysis patients. High CCI score and hypoalbuminaemia significantly increase risk of fracture.

Roles of neutrophil gelatinase-associated lipocalin in continuous ambulatory peritoneal dialysis-related peritonitis.

INTRODUCTION: We measured the neutrophil gelatinase-associated lipocalin (NGAL) concentration in peritoneal dialysate effluent (PDE) collected following an acute episode of continuous ambulatory peritoneal dialysis (CAPD)-related peritonitis. RESULTS: NGAL concentration in PDE increased in the first 3 days after developing peritonitis and correlated well with the neutrophil count. In patients with culture-negative peritonitis, the NGAL in PDE was lower than that in patients with gram-positive or gram-negative peritonitis. Apart from providing additional diagnostic support to bacterial-induced peritonitis, measurement of NGAL in PDE may be useful to differentiate the neutrophil-dependent culture-negative peritonitis from that associated with non-bacterial or non-cellular etiologies. CONCLUSION: Human peritoneal mesothelial cell (HPMC) is another source of NGAL during peritonitis. NGAL was specifically induced in HPMC by IL-1beta. Incubation of HPMC with recombinant NGAL reversed the transforming growth factor-beta-induced up-regulation of Snail and vimentin but rescued the down-regulation of E-cadherin. Our data suggest that NGAL may exert a protective effect in modulating the epithelial-to-mesenchymal transition activated following peritonitis.

Prevalence of Cognitive Impairment Among Peritoneal Dialysis Patients, Impact on Peritonitis and Role of Assisted Dialysis.

UNLABELLED: ♦ BACKGROUND: Chronic renal failure and aging are suggested as risk factors for cognitive impairment (CI). We studied the prevalence of CI among peritoneal dialysis (PD) patients using Montreal Cognitive Assessment (MoCA), its impact on PD-related peritonitis in the first year, and the potential role of assisted PD. ♦ METHODS: One hundred fourteen patients were newly started on PD between February 2011 and July 2013. Montreal Cognitive Assessment was performed in the absence of acute illness. Data on patient characteristics including demographics, comorbidities, blood parameters, dialysis adequacy, presence of helpers, medications, and the number PD-related infections were collected. ♦ RESULTS: The age of studied patients was 59±15.0 years, and 47% were female. The prevalence of CI was 28.9%. Patients older than 65 years old (odds ratio [OR] 4.88, confidence interval [CI] 1.79 - 13.28 p = 0.002) and with an education of primary level or below (OR 4.08, CI 1.30 - 12.81, p = 0.016) were independent risk factors for CI in multivariate analysis. Patients with PD-related peritonitis were significantly older (p < 0.001) and more likely to have CI as defined by MoCA (p = 0.035). After adjustment for age, however, CI was not a significant independent risk factor for PD-related peritonitis among self-care PD patients (OR 2.20, CI 0.65 - 7.44, p = 0.20). When we compared patients with MoCA-defined CI receiving self-care and assisted PD, there were no statistically significant differences between the 2 groups in terms of age, MoCA scores, or comorbidities. There were also no statistically significant differences in 1-year outcome of PD-related peritonitis rates or exit-site infections. ♦ CONCLUSION: Cognitive impairment is common among local PD patients. Even with CI, peritonitis rate in self-care PD with adequate training is similar to CI patients on assisted PD.

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

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

Retroperitoneal leakage as a cause of ultrafiltration failure.

We report 3 patients on continuous ambulatory peritoneal dialysis (CAPD) who developed reversible ultrafiltration failure secondary to retroperitoneal leakage. The patients presented with pulmonary edema and fluid overload following a sudden onset of ultrafiltration failure on maintenance CAPD. There was no localized edema, suggesting peritoneal leakage in the abdominal wall or the perineum. Radiological examination showed no migration of the Tenckhoff catheter. Leakage of dialysate into the retroperitoneal space was only revealed by computed tomographic (CT) peritoneography. These patients were then treated with intermittent peritoneal dialysis twice weekly. After repeated CT peritoneography showing complete resolution of the leakage, they successfully resumed CAPD treatment 2 months later, without ultrafiltration problems. Our finding suggests that retroperitoneal leakage could be one of the uncommon, yet reversible, causes of acute ultrafiltration failure that can be diagnosed with CT peritoneography.

Streptococcus bovis peritonitis complicating peritoneal dialysis--a review of 10 years' experience.

OBJECTIVE: An association of Streptococcus bovis bacteremia with carcinoma of colon has been reported, but data regarding peritoneal dialysis (PD) peritonitis caused by S. bovis is scarce. In this study, we examined the clinical characteristics, associations, and outcomes of this disease entity. METHODS: The case records of patients with S. bovis PD peritonitis presenting to 2 renal centers between January 2000 and September 2010 were reviewed. Clinical features and outcomes were identified and analyzed. RESULTS: Of cultures from 23 episodes of S. bovis peritonitis in 20 patients (1.28% of all peritonitis episodes at our center), 19 (82.6%) showed S. bovis alone, and 4 (17.4%) showed mixed growth. In 7 episodes, the S. bovis was moderately resistant to penicillin G. Rates of resistance to clindamycin and erythromycin were 43.5% and 47.8% respectively. In 18 episodes (78.3%), a primary response was achieved with a first-generation cephalosporin and an aminoglycoside. In 4 episodes, a secondary response was achieved after a switch from cephalosporin to vancomycin, and in 1 episode with mixed growth, the Tenckhoff catheter had to be removed. Repeat peritonitis occurred in 3 patients at a mean of 50.0 months (range: 24.2 - 83.1 months). Of the 20 patients of S. bovis peritonitis, 10 (50%) underwent either a barium enema or a colonoscopy. One patient had history of colonic carcinoma 2 years before the peritonitis, and a subsequent work-up revealed no recurrence. Three patients had diverticulosis, and one had a concomitant sigmoid polyp. Findings in the other 6 patients were normal. No colorectal malignancy had developed in the remaining 10 patients after a mean follow-up of 76.6 months (range: 0.8 - 125.1 months). CONCLUSIONS: Outcomes in S. bovis PD peritonitis were favorable, and an association with colorectal cancer was not found in our patients. Routine colonoscopy in these patients remains controversial and should be individualized.

A prospective randomized study on three different peritoneal dialysis catheters.

OBJECTIVE: We compared outcomes for catheters with different configurations: conventional straight, swan-neck straight tip, and swan-neck curled tip. DESIGN: The study was conducted as a prospective randomized controlled trial in the continuous ambulatory peritoneal dialysis (CAPD) unit of a university center. PATIENTS AND METHODS: We randomized 93 new regular CAPD patients without prior peritoneal dialysis (PD) catheter insertion to receive a conventional straight, double-cuffed catheter (CS), a swan-neck straight catheter (SNC), or a swan-neck curled tip catheter (SNC) in 2:1:1 ratio. RESULTS: The exit-site infection (ESI) rate was slightly lower with swan-neck catheters as compared with straight catheters, but the difference was not statistically significant. The peritonitis rate and overall catheter survival were similar. In Staphylococcus aureus nasal non carriers as compared with carriers, ESI-free catheter survival was significantly better with swan-neck catheters (p = 0.0302 and p = 0.82 respectively). As compared with SC catheters, SNC catheters had a significantly higher migration rate (p = 0.022). CONCLUSIONS: Swan-neck catheters were associated with a slightly better ESI rate, but SNC catheters are not routinely recommended because of a high migration rate. The SNS catheter is therefore recommended as the first-line catheter of choice, particularly in populations with a low rate of S. aureus nasal carriage.

Incidence and outcome of antiglomerular basement membrane disease in Chinese.

BACKGROUND: Antiglomerular basement membrane (anti-GBM) disease is an uncommon disease, especially among Asian population. Many reports and studies on this condition in the Caucasian population are available, but little information exists on anti-GBM disease in Asians. To study the incidence and clinical characteristics of anti-GBM disease among Chinese patients, we reviewed our experience of anti-GBM disease in our hospital (Queen Mary Hospital, Hong Kong) from 1992 to 2003. METHODS: All patients who were admitted for acute renal impairment, which was caused by crescentic glomerulonephritis associated with linear immunoglobulin G (IgG) staining on immunofluorescence, were included in the analysis. Serum anti-GBM antibodies were detected by either enzyme-linked immunofluorescence or indirect immunofluorescence. Ten patients were treated for anti-GBM disease during this 11-year period, yielding an incidence of approximately 0.6 cases per million population per year. RESULTS: In this cohort, anti-GBM disease predominantly affected older patients (mean age: 58.6 +/- 21.7 years). Eight patients were aged between 60 and 80 years and there was a female preponderance (M:F = 2:8). The 1-year renal and patient survival was 15% (95% CI 0-40%) and 70% (95% CI 42-98%), respectively. Most patients presented with non-specific symptoms as well as impaired renal function. Detection of anti-GBM antibody provided a good screening test for the disease. Antiglomerular basement membrane antibodies were not detected in two patients. All but two patients received steroid, cyclophosphamide and intensive plasmapheresis therapy. Haemoptysis occurred in four patients (40%), and usually lagged behind the renal presentation and commencement of treatment. Six patients required long-term dialysis after the acute disease. Three patients died from the disease, two died from pulmonary complications and one died suddenly after a partial recovery of renal function. CONCLUSION: Antiglomerular basement membrane disease is uncommon among the Chinese population. It predominantly affects older patients, and prognosis is poor. Long-term preservation of renal function after the initial attack is unusual.