Differential Diagnosis for Multiple Boils on Labial Majora and Buttock

The patient's presentation of multiple boils on her right labial majora and one on her right buttock, coupled with a history of MRSA, suggests several potential diagnoses. These can be categorized as follows:

• Single Most Likely Diagnosis

  • MRSA Infection: Given the patient's history of MRSA and the presence of boils, which are a common manifestation of MRSA infections, this is the most likely diagnosis. MRSA can cause skin and soft tissue infections, including boils (furuncles), and the patient's history increases the likelihood of this diagnosis.

• Other Likely Diagnoses

  • Folliculitis: This is an inflammation of the hair follicles, which can be caused by bacterial infections, including MRSA. It presents with small, pus-filled bumps and could be considered given the patient's symptoms.
  • Furuncles/Carbuncles: These are more severe forms of folliculitis and can occur when several follicles become infected, forming a larger, more painful nodule or cluster of nodules. The patient's boils could be classified under this category.
  • Hygiene-related Skin Infections: Poor hygiene can lead to bacterial infections of the skin, including the areas mentioned. However, the patient's history of MRSA makes this less likely as the primary cause.

• Do Not Miss Diagnoses

  • Necrotizing Fasciitis: Although less common, this is a severe infection that can start with symptoms similar to those of a boil but rapidly progresses to necrosis of the fascia and surrounding tissues. It is critical to identify early due to its high mortality rate.
  • Cellulitis: An infection of the skin and subcutaneous tissues, which can spread rapidly. While it might not initially present as a boil, it's essential to consider, especially in the context of MRSA.
  • Ecthyma: A variant of impetigo that can extend into the dermis, causing deeper, more ulcerative lesions. It's less likely but could be considered, especially if the lesions have ulcerated.

• Rare Diagnoses

  • Hidradenitis Suppurativa (HS): A chronic skin condition characterized by recurrent, painful nodules, abscesses, and tunnels in skin areas with apocrine sweat glands, such as the groin and buttocks. While it could explain the location of the boils, the patient's history of MRSA and the acute presentation make this less likely.
  • Kerion: A severe form of tinea capitis (ringworm of the scalp) that can cause large, painful, swollen masses, but it's highly unlikely given the locations of the boils.
  • Actinomycosis: A rare chronic bacterial infection that can cause abscesses and sinus tracts, typically in the face and neck but can occur in the pelvic area. It's an unlikely diagnosis given the acute presentation and lack of other symptoms.