Acute Bacterial Skin and Skin Structure Infections (ABSSSI)

Practice Guidelines for Management and Care Transitions in the Emergency Department and Hospital

Charles V. Pollack Jr., MA, MD; Alpesh Amin, MD, MBA; William T. Ford Jr., MD, SFHM; Richard Finley, MD; Keith S. Kaye, MD, MPH; Hien H. Nguyen, MD, MS; Michael J. Rybak, PHARMD, MPH; David Talan, MD


J Emerg Med. 2015;48(4):508-519. 

In This Article

Abstract and Introduction


Background Acute bacterial skin and skin structure infections (ABSSSI), formally referred to as complicated skin and soft tissue infections, include infections with resistance to previously effective antimicrobials. Increasing dramatically in incidence, they have become a challenging medical problem associated with high direct and indirect costs to both the medical system and society.

Objectives To describe the burden of ABSSSI and to explore multidisciplinary approaches to its management and new treatments that can be initiated in the emergency department.

Discussion We offer a best practice model aimed at providing risk-stratified and convenient care for ABSSSI at the lowest possible cost, while minimizing complications, readmissions, and inappropriate antibiotic use. In doing so, we focus on the care provided by emergency physicians and hospitalists and the transition of management between them for inpatient care, as well as the facilitation of observation or direct-to-outpatient care for suitable patients.

Conclusions A standard, consistent, and multidisciplinary approach to ABSSSI can streamline care, reduce admissions, support antimicrobial stewardship, and improve clinical and resource consumption outcomes.


Acute bacterial skin and skin structure infections (ABSSSI) have become a challenging medical problem associated with high direct and indirect costs to both the medical system and society. Infections due to bacteria with resistance to previously effective antimicrobials such as methicillin-resistant Staphylococcus aureus (MRSA) are increasing in incidence and have led to higher rates of complications and hospitalization. MRSA has emerged as the most common cause of purulent infections in the United States and many other areas. Meeting the challenge to deliver efficient health care not only demands that we recognize and treat individual patients; we must also define strategies to optimize patient flow and resource utilization. An important goal is to limit inpatient stays and reduce hospital readmissions through seamless transitions of care from the emergency department (ED) into the hospital medicine service, and then out to the community. The purpose of this report is to describe a best practice model for patient care and resource management in ABSSSI.

Why ABSSSI and not cSSTI?

The terms "skin and skin structure infection" and "skin and soft tissue infection" (SSTI) were coined to describe infectious processes such as cellulitis, erysipelas, cutaneous abscesses, and infected wounds, ulcers, or burns. The designation of more severe SSTI included a lowercase "c" (cSSTI) for "complicated" skin and soft tissue infection and typically implied a need for inpatient management, surgical procedures, or a significant underlying comorbidity such as diabetes or systemic immunosuppression that complicates response to therapy.

In 2013, to identify more clearly a severe subset of SSTI that would typically be treated with parenteral antibiotic therapy, the United States (US) Food and Drug Administration (FDA) issued guidance that standardized the nomenclature to be used in the evaluation of new antimicrobial treatments for cSSTI, which are now referred to as acute bacterial skin and skin structure infections, or ABSSSIs. The rationale for developing this terminology was to provide a consistent means of identifying infections for which a reliable drug treatment effect can be estimated. The agents to be studied under the new definition are most often administered parenterally, and patient level of illness is reflected in parameters such as lesion size, leukocytosis, fever, and systemic inflammatory response syndrome.[1]

The specific verbiage from the FDA is as follows:

ABSSSIs include cellulitis/erysipelas, wound infection, and major cutaneous abscess with a minimum lesion surface area of 75 cm 2. Diabetic foot ulcers and burn wound infections are excluded. Bacterial pathogens that commonly cause ABSSSI include Streptococcus pyogenes and Staphylococcus aureus, including MRSA strains. Less commonly identified bacteria include other Streptococcus species, Enterococcus faecalis, and Gram-negative bacteria. [1]

Although various terms appear in the literature and some of the studies discussed in this review used the terms cSSSI or cSSTI, we will use ABSSSI consistently to describe these complicated infections, to avoid confusion. The primary etiologic organism of concern in ABSSSI is MRSA, and most novel antimicrobials studied to date under the new FDA guidance target MRSA specifically.