A young man is seen in a shelter in San Antonio after being evacuated from New Orleans after the devastating floods of Hurricane Katrina (Figure 121-1). He has facial pain and swelling and noticeable pus near the eye. His vision is normal. The area is anesthetized with lidocaine and epinephrine. The abscess is drained with a #11 blade. The patient is started on an oral antibiotic because of the proximity to the eye and the local swelling that could represent early cellulitis. A culture to look for methicillin-resistant Staphylococcus aureus (MRSA) was not available in the shelter, but close follow-up was set for the next day and the patient was doing much better.
Abscess seen on the face of a man after evacuation from the flood waters of New Orleans following Hurricane Katrina. (Courtesy of Richard P. Usatine, MD.)
An abscess is a collection of pus in the infected tissues. The abscess represents a walled-off infection in which there is a pocket of purulence. In abscesses of the skin the offending organism is almost always S. aureus.
Collection of pus in or below the skin. Patients often feel pain and have tenderness at the involved site. There is swelling, erythema, warmth, and fluctuance in most cases (Figures 121-1, 121-2, Figures 121-3, 121-4, 121-5). Determine if the patient is febrile and if there is surrounding cellulitis.
A large abscess of the hand in a 2-year-old girl in Ethiopia. Incision and drainage was performed and antibiotics were given to cover the surrounding cellulitis and any deeper infections. (Courtesy of Richard P. Usatine, MD.)
Skin abscesses can be found anywhere from head to feet. Frequent sites include the hands, feet, extremities, head, neck, buttocks, and breast (Figure 121-5).
Clinical cure is often obtained with incision and drainage alone so the benefits of pathogen identification and sensitivities are low in low-risk patients.2 Most clinical studies have excluded patients who were immunocompromised, diabetic, or had other significant comorbidities.2 Consequently, it may be reasonable to obtain wound cultures in high-risk patients, those with signs of systemic infection, and in patients with history of high recurrence rates.2,3
- The evidence strongly supports the incision and drainage of an abscess.2,4 SOR A Inject 1% lidocaine with epinephrine into the skin at the site you plan to open using a 27-gauge needle. A ring block can be helpful rather than injecting into the abscess itself (Figure 121-3). Open the abscess with a linear incision using a #11 blade scalpel following skin lines if possible.5
Although many physicians still pack a drained abscess with ribbon gauze, there is limited data on whether or not packing of an abscess cavity improves outcomes. A small study concluded that routine packing of simple cutaneous abscesses is painful and probably unnecessary.6 SOR C The author of this chapter often packs abscesses lightly and has the patient remove the packing in the shower 2 days later, avoiding additional visits and painful repacking of the healing cavity. SOR C However, if a large abscess is not packed it can seal over and the pus may reaccumulate.
Routine use of antibiotics for an initial abscess in addition to incision and drainage is not supported by current evidence.2,7-9 SOR A Three randomized controlled trials (RCTs) performed since the emergence of CAMRSA have demonstrated that antibiotics do not significantly improve healing rates of superficial skin abscesses, but two of these studies suggest that antibiotics do decrease short-term rates of new lesion development.7-9
Consider the use of oral antibiotics to treat an abscess with suspected CAMRSA in patients who are febrile or have systemic symptoms, have significant surrounding cellulitis, have failed incision and drainage alone, have frequent recurrences, or have a history of close contacts with abscesses.2 SOR C
If an antibiotic is to be used, CAMRSA is close to 100% sensitive to trimethoprim-sulfamethoxazole.2 SOR B Although standard dosing of oral trimethoprim-sulfamethoxazole for an infection in adults is 1 DS tablet bid, one study suggests that 2 DS tablets should be used bid for 7 days.10 SOR B Alternative antibiotics include oral clindamycin, tetracycline, or doxycycline. Local sensitivity data should be consulted when available.2 SOR B
There is no current data to support the use of an antimicrobial medication (mupirocin or rifampin) in the eradication of MRSA colonization.2 SOR C
Patients may shower daily 24 to 48 hours after incision and drainage and then reapply dressings. Patients should be given return precautions for worsening of symptoms or continued redness, pain, or pus.
In patients or wounds at higher risk for complications, follow-up should be scheduled in 24 to 48 hours. If packing was placed, it can be removed by the patient or a family member.