Nephrotoxicity Risk Factors and Intravenous Vancomycin Dosing in the Immediate Postoperative Period Following Antibiotic-Impregnated Cement Spacer Placement.

BACKGROUND: Several case reports have documented acute kidney injury (AKI) attributable to antibiotic-impregnated cement (AIC) spacers. OBJECTIVES: To identify AKI risk factors among patients who underwent AIC placement and determine whether vancomycin-AIC placement affects systemic vancomycin dosing. METHODS: Phase 1 was a case-control study to identify AKI risk factors among patients who underwent AIC placement. Cases experienced AKI; controls had unchanged renal function. Phase 2 was a retrospective cohort study. Patients who received ≥72 hours of intravenous (IV) vancomycin were divided into 2 groups according to whether they underwent vancomycin-AIC placement. Primary outcome was number of vancomycin dosing changes. RESULTS: Phase 1: Among 26 cases and 74 controls AKI risk factors on univariate and multivariable analysis included exposure to angiotensin-converting-enzyme (ACE) inhibitor exposure within 7 days of AIC placement (42% vs 20%, P = 0.03) and piperacillin-tazobactam within 7 days following AIC placement (31% vs 12%, P = 0.03). Phase 2: Among 53 patients who underwent vancomycin-AIC placement and 104 who underwent another surgery type, vancomycin was adjusted more frequently in patients who underwent vancomycin-AIC placement (28% vs 15%, P = 0.06). CONCLUSIONS: Among patients who undergo AIC placement with vancomycin and/or tobramycin, exposure to ACE inhibitors and piperacillin-tazobactam are associated with increased risk of AKI in the immediate postoperative period. No empirical adjustments to IV vancomycin dosing are necessary in patients undergoing vancomycin-AIC placement.

Kerstersia gyiorum Isolated from a Bronchoalveolar Lavage in a Patient with a Chronic Tracheostomy.

The use of the matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry (MS) generates rapid microbial identification. We are presenting a case of a 63-year-old woman with a medical history of chronic tracheostomy admitted for hypotension and fevers to illustrate the clinical implication of MALDI-TOF MS on bacterial identification. Kerstersia gyiorum was identified from the bronchoalveolar lavage isolate. Kerstersia gyiorum has been isolated from human sputum samples, and may be a previously unrecognized colonizer of the upper respiratory tract. Thus, patients with long-term tracheotomies or who are chronically aspirating may be at risk of lower respiratory infection with this organism. Increased use of MALDI-TOF MS in the clinical setting may increase reporting of this atypical isolate.