Dialister pneumosintes and aortic graft infection - a case report.

BACKGROUND: Dialister pneumosintes is an anaerobic, Gram negative bacillus, found in the human oral cavity and associated with periodontitis. It has also been isolated from gastric mucosa and stool samples. Recent case reports implicate D. pneumosintes in local infection such as dental root canals, sinusitis, Lemierres syndrome and brain abscesses, as well as distal infections of the liver and lung through haematogenous spread. CASE PRESENTATION: We present a novel case of aortic graft infection and aortoenteric fistula (AEF) in a 75 year old Caucasian male, associated with D. pneumosintes bacteraemia. Microbiological evaluation of septic emboli in the lower limbs revealed other gastrointestinal flora. This suggests either AEF leading to graft infection and subsequent distal emboli and bacteraemia, or a dental origin of infection which seeded to the graft, resulting in AEF and systemic infection. To our knowledge this is the first report of D. pneumosintes associated aortic graft infection. The patient underwent surgical explantation, oversew of the aorta and placement of extra-anatomical bypass graft in conjunction with antimicrobial therapy, making a good recovery with discharge home after a 35-day hospital admission. CONCLUSION: We report a case of Dialister pneumosintes bacteraemia associated with aortic graft infection. To our knowledge, vascular graft-associated infection with D. pneumosintes has not been reported before.

Metabolomic analysis of perfusate during hypothermic machine perfusion of human cadaveric kidneys.

BACKGROUND: The metabolic processes occurring within the preserved kidney during hypothermic machine perfusion (HMP) are not well characterized. The aim of this study was to use nuclear magnetic resonance (NMR) spectroscopy to examine the metabolomic profile of HMP perfusate from human cadaveric kidneys awaiting transplantation and to identify possible discriminators between the profiles of kidneys with delayed graft function (DGF) and immediate graft function (IGF). METHODS: Perfusates from HMP kidneys were sampled at 45 min and 4 hr of preservation with the LifePort Kidney Transporter 1.0 (Organ Recovery Systems, Chicago, IL) using KPS-1. Prepared samples underwent 1-D Proton-NMR spectroscopy, and resultant spectra were analyzed. Clinical parameters were collected prospectively. RESULTS: Perfusate of 26 transplanted cadaveric kidneys was analyzed; 19(73%) with IGF and 7(27%) with DGF. Glucose concentrations were significantly lower in DGF kidneys compared to those with IGF at both 45 min (7.772 vs. 9.459 mM, P = 0.006) and 4 hr (8.202 vs. 10.235 mM, P = 0.003). Concentrations of inosine and leucine were significantly different between DGF and IGF kidneys at 45 min (0.002 vs. 0.013 mM, P = 0.009 and 0.011 vs. 0.006 mM, P = 0.036), and gluconate levels were also significantly different between DGF and IGF kidneys at 4 hr (49.099 vs. 59.513 mM, P = 0.009). CONCLUSION: Significant metabolic activity may be occurring in kidneys during HMP. The NMR spectroscopy of the perfusate can identify differences in the metabolomic profiles of DGF and IGF kidneys that might have a predictive role in viability assessment. Modification of harmful metabolic processes may improve outcomes for HMP kidneys.