Differential Diagnosis for Left Breast Lesion
Single Most Likely Diagnosis
- Cellulitis with Abscess Formation: The patient's symptoms of redness, swelling, warmth, and pain, along with the history of a raised area with a black middle and the expression of pus after showering, are consistent with cellulitis complicated by an abscess. The recent onset and the patient's report of less pain and warmth after pus drainage support this diagnosis.
Other Likely Diagnoses
- Infected Epidermal Inclusion Cyst: The description of a raised area with a black middle could suggest an infected epidermal inclusion cyst, which can become inflamed and infected, leading to symptoms similar to those described.
- Furuncle or Carbuncle: These are infections of the hair follicle that can cause redness, swelling, and pus, similar to the patient's symptoms.
- Spider Bite Reaction: Although less common, a severe reaction to a spider bite could cause localized redness, swelling, and pain, as the patient initially suspected.
Do Not Miss Diagnoses
- Breast Abscess: Especially in a patient with a history of cancer, it's crucial to consider a breast abscess, which can present similarly to cellulitis but requires specific management, including drainage.
- Necrotizing Fasciitis: This is a severe infection that can cause pain, redness, and swelling, and it is critical to diagnose early due to its high morbidity and mortality.
- Inflammatory Breast Cancer: Although the patient is cancer-free, inflammatory breast cancer can mimic infections and must be considered, especially given the patient's history of cancer.
Rare Diagnoses
- Erysipelas: A type of skin infection that can cause redness and swelling, typically affecting the upper dermis, and is less common than cellulitis.
- Actinomycosis: A rare bacterial infection that can cause abscesses and sinus tracts, which might be considered if the patient does not respond to typical antibiotic treatments.