Differential Diagnosis for Rash Under the Breast
- Single most likely diagnosis
- Intertrigo: This is the most common diagnosis for a rash under the breast. It is a type of skin inflammation caused by friction, moisture, and bacterial or fungal infections in the skin folds. The warm, moist environment under the breast creates an ideal condition for intertrigo to develop.
- Other Likely diagnoses
- Eczema (atopic dermatitis): Can occur in skin folds, including under the breast, and is characterized by itchy, inflamed skin.
- Contact dermatitis: An allergic reaction or irritation from materials like fabric, detergents, or perfumes can cause a rash under the breast.
- Fungal infections (e.g., candidiasis): Fungi thrive in warm, moist areas, making the under-breast area susceptible to infections like candidiasis.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed)
- Inflammatory breast cancer: Although rare, it presents with skin changes, including redness and swelling, often without a distinct lump. It's crucial to consider this in the differential diagnosis due to its aggressive nature and poor prognosis if not treated promptly.
- Cellulitis: A bacterial infection of the skin and subcutaneous tissues that can spread rapidly and become severe if not treated with antibiotics.
- Rare diagnoses
- Inverse psoriasis: A type of psoriasis that occurs in the folds of the skin, including under the breast, characterized by smooth, red patches.
- Granuloma gluteale infantum: Although more common in the diaper area of infants, it can occasionally occur in other skin folds, including under the breast, and is characterized by reddish-brown nodules.
- Fox-Fordyce disease: A rare skin condition characterized by itchy, dome-shaped bumps in the apocrine sweat glands, which can be found in the under-breast area.