Outpatient parenteral antibiotic therapy (OPAT) is a key part of the treatment of severe infection. One indication for OPAT is methicillin-resistant Staphylococcus aureus (MRSA) bacteremia. Few data have been published regarding long-term follow up and outcomes among patients in an OPAT program (OPAT-P). We describe OPAT-P outcomes at an academic medical center with a focus on MRSA bacteremia (MRSA-B).
A retrospective chart review was performed. Two cohorts of patients were studied. The first comprised all adult inpatients enrolled in OPAT-P at discharge from 7/2016 to 12/2017. The second cohort was a subset of these patients treated for MRSA-B. Outcomes (including readmissions, emergency room (ER) visits, microbiological recurrences, and death) were compared to outcomes among non-OPAT-P patients discharged on IV antibiotics for MRSA-B between 1/2015 and 12/2017. Statistical measures including Chi square tests or Fisher’s exact tests were used.
561 patients were enrolled in OPAT-P from 7/2016 to 12/2017. Common indications were osteomyelitis (n=219, 39%), bacteremia (n=73, 13%), and endocarditis (n=73, 13%); 22% had polymicrobial infection. 61 (11%) were rehospitalized and 24 (4%) had an ER visit for an infectious or OPAT issue while on therapy. 51 adverse events occurred that did not result in ER visit or a readmission. 93 (17%) required antibiotic dose changes. 25 patients were treated for MRSA-B; 83 additional non-OPAT-P patients were discharged on IV therapy for MRSA-B from 1/2015 to 12/2017. Common sources of bacteremia included central line (n=24, 22%), cellulitis (n=18, 16%), and osteomyelitis (n=9, 8%). No MRSA-B patients died within 30 days of discharge. Overall 6-month readmission and ER visit rates did not differ based on OPAT-P enrollment (54%, p = 0.46 and 57%, p = 0.43, respectively). 3/25 (12%) MRSA-B OPAT-P patients and 9/83 (74%) MRSA-B non-OPAT-P patients were readmitted for OPAT or infectious complications (p=NS). Microbiological recurrence was rare.
Adverse events in OPAT are common and antibiotic monitoring is crucial for OPAT safety. A dedicated OPAT-P has the potential to proactively identify adverse events and change therapy to prevent unplanned admission or ER visit. Further data are needed to clarify whether an OPAT-P may improve MRSA-B post-discharge outcomes.
W. Greendyke, None