Case report

Community-Acquired Methicillin-Resistant Staphylococcus aureus Infection With Fatal Necrotizing Pneumonia From Lip Abscess: A Case Report

Staphylococcus aureus is a gram-positive, facultative anaerobic, cocci bacterium that naturally colonizes the skin. S aureus can cause a mild to severe infection depending on the location, depth of invasion, and immune status. Guidelines regarding treatment of patients with lip infections are scant. The purpose of this study was to present the diagnosis, management, and outcome of a cohort of patients with lip infections caused by S aureus.

This was a retrospective cohort study of patients with a lip infection caused by S aureus treated by Emory Oral and Maxillofacial Surgery Service (Atlanta, GA). Predictor variables were patient demographic characteristics, clinical presentation, laboratory findings, imaging characteristics, intervention, and length of stay. The outcome variable was infection resolution or persistence. Data were collected using a standardized collection form. Descriptive statistics were computed.

Seven patients (mean age, 38 years) with lip swelling met the inclusion criteria. The patients did not undergo recent hospitalization and/or recent surgery. Patients had immunodeficiency virus or other medical comorbidities. Radiographic findings were consistent with abscess formation. Management consisted of antibiotics only or surgical intervention with antibiotics. Lip cultures showed S aureus with methicillin-sensitive or -resistant S aureus. Treatment was intravenous followed by oral antibiotics. The average length of inpatient stay was 4 days. There were no postoperative complications. All lip infections achieved complete clinical resolution.

In this cohort, treatment of lip swelling caused by S aureus required surgical intervention and/or antibiotics. Immune compromise and antibiotic resistance should be considered in a patient with a similar presentation.

It is rare for angioedema to be misidentified by the experienced clinician or for it to mimic another disease process. As an Emergency Physician, it is important to recognize and treat angioedema immediately. Of equal importance is the recognition and initiation of treatment of facial cellulitis. A case report follows that illustrates methicillin-resistant Staphylococcus aureus (MRSA) lip infection mimicking angioedema.

Here, we describe a case of a 21-year-old man who presented with a swollen lower lip, initially diagnosed as angioedema. Further investigation revealed the cause of his lip swelling was actually a MRSA abscess and surrounding cellulitis, an unusual presentation for lip infection, which we discuss below.

Misidentifying MRSA lip infection for angioedema, with a delay in proper treatment, could result in serious morbidity or mortality.