Background: Inappropriate use of MRSA-spectrum antibiotics is an important antimicrobial stewardship target. Contributors to inappropriate use include empiric treatment of patients who are determined to not be infected or who are infected but lack MRSA risk factors, and by excessive treatment duration when suspected MRSA infection is disproven. To characterize opportunities for improvement, we conducted a medical use evaluation (MUE) in 27 VA medical centers. The primary objectives were to assess the following proportions: (1) courses of unjustified empiric vancomycin therapy (patients in whom all antibacterials were halted within 2 days or without a principal or secondary discharge infection diagnosis); (2) courses of unjustified continuation of anti-MRSA therapy beyond day 4 (no MRSA risk factors or proven MRSA infection); and (3) excess anti-MRSA days of therapy (DOT), that is, DOT in unjustified empiric courses plus DOT after day 4 in unjustified continued courses. Methods: Clinical pharmacists performed retrospective, structured, manual record reviews of patients started on intravenous vancomycin on day 1 or 2 of hospitalization from June 2017 to May 2018. Exclusion criteria included surgical prophylaxis, recent MRSA infection, β-lactam allergy, renal insufficiency, severe immunosuppression, or infection that warranted anti-MRSA therapy other than vancomycin. Results: Of 2,493 evaluated patients, 1,320 met the inclusion criteria. Among them, 44% of courses were initiated in the emergency department, 37% of patients had ≥1 risk factor for healthcare-associated infections, and 50% of patients had ≥2 SIRS criteria or required vasopressor support. The most common admission diagnoses were skin and soft-tissue infection (SSTI, 40%; 68% nonpurulent) and pneumonia (27%; 46% without healthcare risk factors). Clinical cultures recovered MRSA from 8% of patients. Empiric therapy was not justified in 342 patients (26%; 57% were clinically stable). Continued therapy was unjustified in 46% of the 320 patients who received >4 days of anti-MRSA therapy. Of all days of anti-MRSA therapy, 23% were unjustified; 65% of these were due to unjustified empiric therapy. Site-specific variations in unjustified empiric therapy better correlated with the proportion of unjustified DOT than did unjustified continuation of therapy (Pearson correlation coefficients [PCC], 0.75 and 0.54, respectively) (Fig. 1). Facility-specific proportions of unjustified DOT modestly correlated with anti-MRSA DOT (PCC, 0.45; n = 27) (Fig. 2) but not the anti-MRSA standardized antimicrobial administration ratio (PCC, 0.15; n = 21). Conclusions: In this multicenter MUE, 26% of all days of anti-MRSA therapy lacked justification; this rate correlated with total facility-specific anti-MRSA DOT. Unnecessary empiric therapy, largely in the ED and for nonpurulent SSTIs and pneumonia without risk factors, was the principal contributor to unjustified DOT.

Funding: None

Disclosures: None

Background: Carbapenem-resistant Acinetobacter baumannii (CRAB), a multidrug-resistant gram-negative bacterium, can cause difficult-to-treat infections with mortality in approximately half of CRAB cases. CRAB can spread among healthcare facilities after transfer of an infected or colonized patient. Strategies to limit CRAB spread include adherence to contact precautions, environmental cleaning with bleach, and screening to identify colonized patients. During July–September 2018, the Connecticut Department of Public Health (DPH) worked with an acute-care hospital (hospital A) to contain an outbreak of OXA-23–producing CRAB (OXA-23 is an enzyme that confers resistance to carbapenems). During November 2018–March 2019, statewide CRAB surveillance identified additional cases of related OXA-23–producing CRAB at other healthcare facilities. DPH, Connecticut State Public Health Laboratory (SPHL), and the Antibiotic Resistance Laboratory Network (ARLN) investigated to prevent additional cases. Methods: Since January 2017, CRAB isolates have been routinely sent to SPHL and ARLN for carbapenemase gene detection and whole-genome sequencing (WGS) to determine isolate relatedness. During November 2018–March 2019, DPH collected patient healthcare history for patients with CRAB isolates to identify outbreaks and provide assistance in infection control and prevention to healthcare facilities reporting CRAB cases. Beginning May 2019, DPH and ARLN offered facilities screening to identify patients colonized with OXA-23–producing CRAB. Results: Of 10 OXA-23–producing CRAB isolates reported to DPH during November 2018–March 2019, 3 were closely related to the 9 isolates from hospital A’s outbreak by WGS (single-nucleotide polymorphism difference range, 1–16). One isolate was from a patient who had been admitted to hospital A during July 2018. All 3 patients with CRAB isolates shared a history of residence at long-term–care facility A (LTCF A). Two patients received a CRAB infection diagnosis upon admission to hospital B after transfer from LTCF A. Both LTCF A and hospital B performed environmental cleaning with bleach and placed CRAB-identified patients on contact precautions. LTCF A declined screening patients for CRAB, whereas hospitals B and C, which receive frequent transfers from LTCF A, screened all patients on admission from LTCF A. During May–September 2019, among 6 patients screened, 1 was colonized with OXA-23–producing CRAB and was placed on contact precautions. Conclusions: Transfer of patients who are infected or colonized with CRAB among hospitals and LTCFs can facilitate the regional spread of CRAB. Strategies for containing the spread of carbapenemase-producing organisms include adherence to contact precautions, colonization screening, interfacility communication, and collaboration with public health.

Funding: None

Disclosures: None