According to the Centers for Disease Control and Prevention (CDC), approximately 51 000 healthcare-associated infections caused by Pseudomonas aeruginosa occur annually in the USA, more than 6000 of which (13%) are caused by multidrug resistant (MDR) strains. Ceftolozane/tazobactam (TOL/TAZ) (Zerbaxa) was approved by the US Food and Drug Administration (FDA) in December 2014 for the treatment of complicated intra-abdominal and urinary tract infections. At this time, clinical data on the role of TOL/TAZ treatment outside of FDA-approved indications is limited. Herein, we present a case of extensively drug-resistant (XDR) P. aeruginosa osteomyelitis of the upper extremity, which was successfully treated with TOL/TAZ for 8 weeks with optimal clinical and laboratory responses. Monotherapy with TOL/TAZ appears effective for treatment of complicated bone and joint infections with XDR P. aeruginosa in combination with comprehensive surgical management, particularly when few antibiotic options exist.

BackgroundIn 2015, a transition-of-care outpatient parenteral antibiotic therapy service (TOC-OPAT) was established at the Montefiore Medical Center in the Bronx, NY for patients requiring long-term antibiotics. Utilizing an OPAT bundle with direct communication between specialists, significant reductions in 30-day readmissions were observed. Montefiore is a regional referral center for orthopedic device-related infections (ODRIs). Here, we evaluate outcomes in TOC-OPAT patients with ORDIs. We hypothesize that a majority achieve infection cure within 6-months.MethodsWe assessed infectious diseases (ID) outcomes in a cohort of TOC-OPAT patients with ODRIs between July 2015 and October 2017. The primary outcome was cure at 6 months defined as (1) infection eradication after initial management, (2) no further surgical or antimicrobial intervention for index infection, and (3) no infection-related mortality. Microbiologic cure for prosthetic joint infection (PJI) was defined as negative joint aspiration cultures prior to revision arthroplasty.ResultsWe reviewed data from 110 infection episodes with 107 unique patients; 2 patients were excluded (deceased from unrelated causes). The average age of patients was 61.5 (demographics shown in Figure 1). There were 80 distinct episodes of PJI (knee, hip, shoulder) and 28 of other ORDI (spine and trauma-related). Of 108 episodes, 91 (84%) were cured by combined surgical and ID management. Patients lost to follow-up (n = 4) were considered non-cured. Microbiologic spectrum of infections is shown in Figure 2. Of 27/80 fluid aspirations prior to revision arthroplasty, four (13%) were positive. Only two patients developed C. difficile infection during the study period (1.8%). Most patients achieved a 50% decline in both erythrocyte sedimentation rate (ESR) and C-reactive protein (CRP) at the end of treatment course (Figure 3). Chronic antibiotic suppression was utilized in 14 (13%) patients, five for chronic active infection and nine for history of multiple prior infections.ConclusionWe observed a high rate of cure in patients managed by a direct orthopedic-ID TOC OPAT service at 6 months. We plan to compare outcomes to a similar cohort of patients predating this multidisciplinary service in future studies. Disclosures All authors: No reported disclosures.