Objectives Total pancreatectomy with islet autotransplantation can relieve pain associated with chronic pancreatitis while preserving islet function. Islet preparations are often contaminated by enteric flora. We assessed the impact of contaminated islet preparations on the prevalence of postoperative infection. Methods Electronic health records for patients who underwent total pancreatectomy with islet autotransplantation from August 1, 2011, to November 15, 2017 were retrospectively reviewed to compare the prevalence of postoperative infection in patients with a positive islet culture and islet culture negative patients. Results Sixty-one patients were included. Twenty-nine patients (47.5%) had a positive islet culture, and 23 (79.3%) of these patients received antimicrobial prophylaxis. The prevalence of postoperative infection did not differ between the islet culture positive and islet culture negative groups (41% vs 34%, P = 0.57). No infections occurred in the 6 islet culture positive patients who did not receive prophylaxis. No difference in intensive care unit or hospital length of stay or in 30-day or 90-day readmission rates were observed. Conclusions Despite the common use of postoperative systemic antimicrobials, we observed no difference in the prevalence of postoperative infection, length of stay, or hospital readmission in patients receiving a contaminated islet preparation. If prophylactic antimicrobials are used, the duration should be minimized.

BackgroundCeftolozane–tazobactam (C/T) was designed to have enhanced activity against P. aeruginosa and has been shown to retain activity against many isolates that are resistant to other antipseudomonal β-lactams. However, there are no data comparing outcomes in patients with and without cystic fibrosis (CF).MethodsRetrospective, multicenter cohort study conducted at 5 hospitals that included all patients with P. aeruginosa infections who received C/T as definitive therapy between November 2016 and December 2018. The primary outcome at 90 days was a composite of mortality, recurrence, readmission, and inappropriate response at end of therapy (EOT). The secondary outcome was to describe baseline C/T susceptibility and emergence of resistance. All outcomes were adjudicated by 2 infectious diseases specialists.ResultsThirty-five, 27 non-CF and 8 CF, patients were included. CF patients were younger, had greater baseline C/T resistance (50.0% vs. 8.3%, P = 0.02) and were more likely to receive combination therapy. The most common site of infection was pulmonary (71.4%) followed by intra-abdominal (14.3%) and osteomyelitis (5.7%). Overall, 54.3% of patients had an unsuccessful outcome with no difference between CF and non-CF patients (62.5% vs. 51.9%, P = 0.70). There was also no difference between each component of the primary outcome. All 4 CF patients with a baseline-resistant isolate had an appropriate response at EOT, while neither of the 2 non-CF patients did. The C/T MIC distribution in CF and non-CF patients was ≤ 2 μg/mL (0.0%, 64.2%), 4 μg/mL (50.0%, 25%) ≥ 8 μg/mL (50.0%, 8.4%). The median duration of C/T in CF and non-CF patients was 18.5 days (interquartile range [IQR], 14–37.5 days) and 15 days (IQR, 10–25 days). Ten, 7 non-CF and 3 CF, patients had a P. aeruginosa isolate cultured and tested for C/T susceptibility within 90 days of index culture with 80% having an MIC increase. Non-CF patients treated for > 14 days were more likely to have an MIC increase (P = 0.047). All CF patients had an MIC increase.ConclusionWe did not observe a difference in the rate of unsuccessful outcome between CF and non-CF patients; however, our sample size was small. CF patients were more likely to be resistant to C/T at baseline. Resistance emerged frequently in both groups following exposure to C/T.Disclosures All authors: No reported disclosures.

Oritavancin and dalbavancin are long-acting lipoglycopeptides with activity against susceptible gram-positive bacteria, including methicillin-resistant Staphylococcus aureus. Though similar in structure to traditional glycopeptide antibiotics like vancomycin, these antibiotics have terminal half-lives >10 days, and, as a result, there is potential for administration of vancomycin to a patient while oritavancin or dalbavancin are still appreciably present in serum. Given the structural similarities, this creates an opportunity for lab assay interference when performing therapeutic drug monitoring for vancomycin. Following higher-than-expected serum vancomycin concentrations in a patient who received both oritavancin and vancomycin within a short time frame, we evaluated the potential for lipoglycopeptide interference with clinical vancomycin assays. Five platforms covering 3 immunoassay technologies were used to quantify vancomycin concentrations in serum spiked with oritavancin or dalbavancin. Oritavancin generated spurious vancomycin concentrations (20%-84% increase) in both enzyme-multiplied immunoassay technique and a particle-enhanced turbidimetric inhibition immunoassay. However, the improper detection of oritavancin was not consistent across all particle-enhanced turbidimetric inhibition immunoassay platforms. Dalbavancin interference was not detected on any of the platforms tested. The interference from oritavancin may result in falsely elevated vancomycin concentrations and, subsequently, inappropriately adjusted vancomycin doses.