Hospital Avoidance Strategies for ABSSSI

More than 40% of patients presenting with acute bacterial skin and skin structure infection (ABSSSI) to the Barnes-Jewish Hospital (BJH) emergency department (ED) are admitted for intravenous antibiotics. There is growing evidence to suggest that many hospital admissions for uncomplicated ABSSSI due to Gram-positive bacteria could be avoided with an alternative treatment strategy employing newer long-acting antibiotics. Coupled with close outpatient follow-up, such an alternative hospital avoidance strategy has the potential to improve quality and value of care for patients with uncomplicated ABSSSI and optimize use of limited inpatient healthcare resources.

This study seeks to establish the feasibility and acceptability of an alternative treatment strategy for uncomplicated acute bacterial skin and skin structure infection (ABSSSI) in the Barnes Jewish Hospital (BJH) Emergency Department (ED) focusing on hospital admission avoidance using single-dose, long-acting antimicrobial therapy complemented by close follow-up in the ambulatory setting. The extended half-life of these new antimicrobials (dalbavancin, oritavancin) allows for an effective treatment course of \>7 days with a single dose, which is the accepted duration for which ABSSSI is usually treated with daily doses of other intravenous or oral antimicrobials. The investigators believe that such an approach will conserve hospital resources by reducing admissions for uncomplicated ABSSSI while delivering comparable if not superior care for this disease, allowing optimal utilization of BJH inpatient beds for other serious medical conditions requiring inpatient care. The investigators believe this novel alternative approach will allow hospitals such as BJH to more cost-effectively and efficiently manage ABSSSI patients. This study will reduce the number of \>2 midnight observation admissions to BJH for ABSSSI, thereby improving inpatient capacity to care for patients requiring \>2 midnight hospital inpatient admission.

The investigators will conduct a randomized controlled trial comparing patients treated with a single-dose of intravenous dalbavancin (an antibiotic that has been FDA-approved for the treatment of ABSSSI and is currently being used in clinical practice in the U.S.) and discharged home from the ED with close ambulatory care follow-up in clinic vs. patients treated with "usual care" (hospital admission for multiple doses of intravenous vancomycin or other antibiotic directed towards Gram-positive bacteria). Clinical outcomes, healthcare utilization, hospital costs, and patient satisfaction will be evaluated.

Eligibility Criteria:
Inclusion Criteria:

* Adult (age ≥18 years)
* Diagnosis of uncomplicated ABSSSI suspected to be due to Gram-positive bacteria by treating ED clinician, with presence of the following:

  1. Skin lesion size ≥75 cm2 (measured by area of erythema, edema, and/or induration) AND
  2. Signs of systemic inflammation (at least 1 of the following: WBC \>12,000 or \<4,000 cells/mm3; ≥10% immature neutrophils on peripheral smear; temperature \>38.3˚C or \<36˚C; heart rate \>90 bpm, respiratory rate \>20 bpm). Signs of systemic inflammation not required if the patient is age \>70 years, has diabetes mellitus, or has been treated with immunosuppressive or chemotherapy in the past 90 days.
* Clinical determination by treating ED clinician that patient will need hospital admission for the sole purpose of receiving intravenous antibiotics directed only towards Gram-positive bacteria (e.g., vancomycin, cefazolin) to treat uncomplicated ABSSSI

Exclusion Criteria:

* Risk for ABSSSI due to Gram-negative bacteria (neutropenia with absolute neutrophil count \<500 cells/µL, HIV or severely immunocompromised, burns, infection after trauma or as a result of an aquatic environment, infection after skin graft)
* Any abscess requiring bedside or operative drainage
* Infection due to a vascular catheter or prosthetic device
* Infection of a diabetic foot ulcer or decubitus ulcer
* Necrotizing soft tissue infection
* Sepsis (quick SOFA score ≥2) or septic shock (requiring vasopressors to maintain mean arterial pressure ≥65 mmHg despite resuscitation with at least 30mL/kg of IV crystalloid within first 3 hours)
* Recent antibiotics in prior 14 days
* Hypersensitivity to glycopeptides (vancomycin, televancin, dalbavancin, oritavancin)
* Severe renal insufficiency (CrCl \<30 mL/min)
* Severe hepatic insufficiency (Child-Pugh Class C)
* Pregnant or nursing