Epidemiology and outcomes of carbapenem-resistant Klebsiella pneumoniae bacteriuria in kidney transplant recipients

BACKGROUND

Little is known about the epidemiology of carbapenem-resistant Klebsiella pneumoniae (CRKP) bacteriuria following kidney transplantation. We determined the incidence of post-transplant CRKP bacteriuria in adults who underwent kidney transplant from 2007 to 2010 at 2 New York City centers.

METHODS

We conducted a case-control study to identify factors associated with CRKP bacteriuria compared with carbapenem-susceptible K. pneumoniae (CSKP) bacteriuria, assessed whether CRKP bacteriuria was associated with mortality or graft failure, and compared outcomes of treated episodes of CRKP and CSKP bacteriuria.

RESULTS

Of 1852 transplants, 20 (1.1%) patients developed CRKP bacteriuria. Factors associated with CRKP bacteriuria included receipt of multiple organs (odds ratio [OR] 4.7, 95% confidence interval [CI] 1.1-20.4), deceased-donor allograft (OR 5.9, 95% CI 1.3-26.8), transplant admission length of stay (OR 1.1 per day, 95% CI 1.0-1.1), pre-transplant CRKP infection or colonization (OR 18.3, 95% CI 2.0-170.5), diabetes mellitus (OR 2.8, 95% CI 1.0-7.8), and receipt of antimicrobials other than trimethoprim-sulfamethoxazole (OR 4.3, 95% CI 1.6-11.2).

CONCLUSION

Compared to CSKP bacteriuria, CRKP bacteriuria was associated with increased mortality (30% vs. 10%, P = 0.03) but not graft failure. Treated episodes of CRKP bacteriuria were less likely to achieve microbiologic clearance (83% vs. 97%; P = 0.05) and more likely to recur within 3 months (50% vs. 22%, P = 0.02) than CSKP episodes. CRKP bacteriuria after kidney transplant is associated with mortality and antimicrobial failure after treatment.

Kidneys at higher risk of discard: expanding the role of dual kidney transplantation

Half of the recovered expanded criteria donor (ECD) kidneys are discarded in the United States. A new kidney allocation system offers kidneys at higher risk of discard, Kidney Donor Profile Index (KDPI)>85%, to a wider geographic area to promote broader sharing and expedite utilization. Dual kidney transplantation (DKT) based on the KDPI is a potential option to streamline allocation of kidneys which otherwise would have been discarded. To assess the clinical utility of the KDPI in kidneys at higher risk of discard, we analyzed the OPTN/UNOS Registry that included the deceased donor kidneys recovered between 2002 and 2012. The primary outcomes were allograft survival, patient survival and discard rate based on different KDPI categories (<80%, 80-90% and >90%). Kidneys with KDPI>90% were associated with increased odds of discard (OR=1.99, 95% CI 1.74-2.29) compared to ones with KDPI<80%. DKTs of KDPI>90% were associated with lower overall allograft failure (HR=0.74, 95% CI 0.62-0.89) and better patient survival (HR=0.79, 95% CI 0.64-0.98) compared to single ECD kidneys with KDPI>90%. Kidneys at higher risk of discard may be offered in the up-front allocation system as a DKT. Further modeling and simulation studies are required to determine a reasonable KDPI cutoff percentile.

Risk factors associated with Clostridium difficile infection after kidney and pancreas transplantation

BACKGROUND

Clostridium difficile infection (CDI) is a common cause of nosocomial antibiotic-associated diarrhea with an increased incidence reported in solid organ transplant recipients. We sought to determine if kidney and/or pancreas transplant recipients possess unique risk factors for CDI.

METHODS

Between January 2009 and February 2011, 942 kidney and 56 pancreas transplants were performed at the 2 centers. Of these, 28 recipients (kidney, n = 24; pancreas, n = 4) developed CDI. Cases were matched to controls (n = 56) in a 1:2 ratio.

RESULTS

Those with CDI were mostly male patients (82% vs. 48%, P = 0.003), deceased-donor organ recipients (86% vs. 64%, P = 0.045), more likely to have leukopenia (18% vs. 4%, P = 0.038), and had undergone a gastrointestinal procedure within 3 months preceding CDI diagnosis (18% vs. 4%, P = 0.038). Cases had higher cumulative and restricted antimicrobial exposure in days (37 ± 79 vs. 8 ± 12, P = 0.009 and 27 ± 69 vs. 7 ± 10, P = 0.032). Cephalosporin use was more common among cases (43% vs. 16%, P = 0.008).

CONCLUSION

Careful antimicrobial selection and assurance of optimal treatment duration in the kidney and pancreas transplant population is prudent. Clinicians should have a heightened awareness of CDI risk particularly during periods of leukopenia and in the setting of gastrointestinal procedures.