Cutaneous Abscess
Information on the causes, symptoms, and treatments for pus accumulation beneath the skin.
Symptoms and Causes
A cutaneous abscess is a collection of pus that forms in the skin as a result of an infection. Although they can appear anywhere on the body, they are more common in areas with increased friction, a higher density of hair follicles, or higher moisture levels.
There are different types of cutaneous abscesses depending on their characteristics and location:
- Superficial cutaneous abscess: occurs in the superficial layers of the skin and is easily visible.
- Furuncle (boil): forms in a hair follicle, which is the cavity where hair grows.
- Carbuncle: a cluster of several furuncles connected under the skin, usually larger in size.
- Hidradenitis suppurativa: affects the sweat glands and typically appears in the axillae, groin, or under the breasts.
- Pilonidal abscess: appears at the base of the spine and usually contains hair.
The prognosis for a cutaneous abscess is generally good if treated promptly. However, inadequate treatment can lead to serious complications.
Symptoms
The most characteristic symptoms of a cutaneous abscess include:
- Localized swelling and erythema. These can appear anywhere on the body but are more frequent in:
- Axillae
- Groin
- Gluteal region
- Face (around the nose, mouth, or eyes)
- Tooth base (dental abscess)
- Base of the spine (pilonidal abscess)
- Perianal area (perianal abscess): the skin surrounding the anus and between the anus and genitals
- Formation of red nodules on the skin, usually between one and three centimeters in diameter.
- Pain
- Fever
- Regional lymphadenopathy: inflammation of the lymph nodes near the abscess, indicating the body is fighting the infection.
- Leukocytosis: an increase in white blood cells in the blood due to the immune system’s effort to eliminate the infection.
Causes
The most common causes of a cutaneous abscess are:
- Bacterial infection, typically by Staphylococcus or Streptococcus species. These organisms normally reside on the skin but can cause infection if they enter through a break in the skin.
- Folliculitis: an infection occurring in a hair follicle.
Risk Factors
Factors that increase the likelihood of developing a cutaneous abscess include:
- Skin wounds or scratches
- Weakened immune system, increasing susceptibility to infections
- Obesity: excess adipose tissue causes chronic inflammation that affects immune function. Additionally, increased moisture in skin folds and a higher prevalence of diabetes exacerbate skin lesions and complicate management.
- Advanced age: natural aging thins and weakens the skin, reducing healing capacity, while also weakening the immune system.
Complications
If not treated properly, an abscess can rupture and release pus (a whitish fluid containing bacteria), increasing the risk of infection spreading to surrounding tissues:
- Local cellulitis: bacterial infection reaching the subcutaneous tissue
- Lymphangitis: inflammation of lymphatic vessels due to infection
Prevention
To prevent cutaneous abscesses, it is recommended to:
- Wash hands frequently with soap and water for at least 15 seconds, especially before and after using the restroom, before eating, after coughing or sneezing, after handling objects, or after being outdoors.
- Clean and properly dry areas of the body prone to friction on a daily basis.
- Keep wounds clean and covered with a dressing to prevent bacterial entry.
Which Specialist Treats Cutaneous Abscesses?
Cutaneous abscesses are diagnosed and treated by Medical-surgical dermatology and venereology and general surgery specialists.
Diagnosis
The diagnosis of a cutaneous abscess is primarily clinical, as the specialist can identify it through observation.
To determine the causative agent, a sample of pus is collected and analyzed in the laboratory. This helps establish whether the infection is bacterial or fungal.
Treatment
Small cutaneous abscesses often resolve spontaneously, with inflammation reducing by applying warm compresses. However, the main treatment is drainage for large or highly painful abscesses. The procedure involves:
- Administering local anesthesia
- Making an incision on the top of the swelling
- Pressing the area to evacuate all pus
- If septations (internal membranes dividing the pus into multiple pockets) are present, using a curette to break them and allow complete drainage
- Cleaning with saline solution
- Packing the cavity with gauze, leaving a portion exposed to ensure continued drainage
- Removing the gauze after 24–48 hours
In most cases, antibiotics are administered to treat the infection, promote recovery, and prevent recurrence.
