Skin abscess: Clinical sciences

A skin abscess is a common skin and soft tissue infection that occurs when a collection of pus accumulates, usually in the dermis or subcutaneous space. An abscess can result from a disruption in the skin barrier or prior skin infection, which allows the bacteria to get into the subcutaneous space. The most common cause of a skin abscess is bacteria, especially Staphylococcus aureus, either methicillin-susceptible or methicillin-resistant. When it comes to presentation, a skin abscess can present with or without systemic symptoms.

Alright, when assessing a patient who presents with signs and symptoms suggestive of a skin abscess, you should first perform an ABCDE assessment to determine if your patient is unstable or stable. If the patient is unstable, stabilize the airway, breathing, and circulation first. Next, obtain IV access and initiate IV fluids for resuscitation.

Here’s a clinical pearl! Keep in mind that most patients with skin abscesses wouldn't be unstable, and if they are unstable, then they’ve likely developed sepsis or even septic shock. So be sure to evaluate these patients for systemic signs and symptoms like hypotension, fever, and chills.

Now that acute management for unstable patients is initiated, let’s talk about stable patients. If the patient is stable, your first step is to obtain a focused history and physical examination, evaluating the affected area while also looking for associated systemic signs and symptoms like fevers or chills; along with labs like CBC.

Let’s first look at a patient without systemic signs and symptoms. Your patient might report a small painful, erythematous nodule, with or without spontaneous drainage. On a physical exam, you might see a fluctuant nodule with or without erythema and tenderness. Finally, labs might be normal or show mild leukocytosis. In this case, you can diagnose a skin abscess. Now, since the patient doesn’t have any systemic signs or symptoms, we can refer to it as an abscess without systemic signs and symptoms.

Okay, now that you have made the diagnosis, the next step is to proceed with a surgical consultation for simple incision and drainage with daily dressing changes.

Once the abscess has been drained, you should wait for 24 to 48 hours to assess the response to treatment. Logically, if the abscess is gone, no further treatment is needed, but remember that dressings will need to be changed daily until the abscess cavity resolves too. Now, in some cases, the abscess might reaccumulate in those 24 to 48 hours. This means that the patient has a refractory abscess secondary to loculations or inadequate drainage procedure. If this is the case, you should consider repeating the incision and drainage, performing debridement, or adding an antibiotic that would cover skin flora, like trimethoprim-sulfamethoxazole, or a first generation cephalosporin such as cephalexin..