The characteristics and outcome of bacteraemia in renal transplant recipients and non-transplant renal patients.

BACKGROUND: There is lack of outcome data for bacteraemic patients on specialist renal units. We described demographic, clinical, microbiological data and outcomes for bacteraemic adult renal transplant and non-transplant patients at a London Teaching Hospital. We also assessed the appropriateness of empirical antibiotic policy. METHODS: From December 2012 to November 2013, demographic, clinical and microbiological data were collected on consecutive patients with bacteraemia on a specialist UK renal unit. Empirical anti-microbial policy, based upon sites of infection, was piperacillin/tazobactam and amikacin, or meropenem for graft pyelonephritis, and vancomycin and gentamicin for suspected central venous catheter (CVC) associated infection. RESULTS: 113 bacteraemic episodes occurred in 83 patients. One patient had two bacteraemic episodes, one on haemodialysis and another after transplantation so appear in both groups. In the non-transplant group, 30-day mortality was 4/59 (6.8 %), more than the renal transplant group, 0/25 (0 %). While graft pyelonephritis was the predominant cause of bacteraemic episodes in renal transplant patients, 25/36 (69.4 %), there were a variety of other causes in the non-transplant group including uncomplicated line associated bacteraemia, 36/77 (46.8 %), complicated line associated bacteraemia, 11/77 (14.3 %) and bacteraemia unrelated to vascular access sites 19/77 (24.7 %). Overall, commonest isolates were Methicillin-sensitive Staphylococcus aureus 20/77 (26.3 %), and Escherichia coli 28/113 (24.8 %). There were no Methicillin-resistant Staphylococcus aureus isolates and, among Enterobacteriaceae, 15/57 (26.3 %) were extended spectrum beta-lactamase producers. CONCLUSIONS: Death only occurred in the non-transplant renal group. Empirical antibiotic treatment with either piperacillin/tazobactam and amikacin, or meropenem was appropriate for renal transplant recipients as most bacteraemic episodes were secondary to graft pyelonephritis. Vancomycin and gentamicin was appropriate empirical antibiotic treatment for non-transplant patients with CVC associated infections, but not optimal for other sites of infection.

Hydration status measured by BCM: A potential modifiable risk factor for peritonitis in patients on peritoneal dialysis.

AIM: Peritoneal dialysis peritonitis and fluid overhydration (OH) are frequent problems in peritoneal dialysis. The latter can cause gut wall oedema or be associated with malnutrition. Both may lead to increased peritonitis risk. We wished to determine if OH is an independent risk factor for peritonitis (caused by enteric organisms). METHODS: Retrospectively study of patients with >2 bioimpedance assessments (Body Composition Monitor). We compared peritonitis rates of patients with above or below the median time-averaged hydration parameter (OH/extracellular water, OH/ECW). Multivariate analysis was performed to determine independent risk factors for peritonitis by enteric organism. RESULTS: We studied 580 patients. Peritonitis was experienced by 28% patients (followed up for an average of 17 months). The overall peritonitis rate was 1:34 patient months. Patients with low OH/ECW values had significantly lower rates of peritonitis from enteric organisms than overhydrated patients (incident rate ratio 1.53, 95% confidence interval 1.38-1.70, P < 0.001). Hydration remained an independent predictor of peritonitis from enteric organisms when multivariate model included demographic parameters (odds ratio for a 1% increment of OH/ECW was 1.05; 95% confidence interval 1.01-1.10, P < 0.02). However, including biochemical parameters of malnutrition reduced the predictive power of overhydration. CONCLUSION: We found an association between overhydration and increased rates of peritonitis. While this may partly be due to the high co-morbidity of patients (advanced age and diabetes), on multivariate analysis, only inclusion of nutritional parameters reduced this association. It remains to be determined if overhydration will prove to be a modifiable risk factor for peritonitis or whether malnutrition will prove to be more important.