Differential Diagnosis for Itchy Rash on Both Breasts

• Single most likely diagnosis
  • Atopic Dermatitis (Eczema): This is a common condition characterized by itchy, inflamed skin. The breasts are a common site for atopic dermatitis, especially in women, due to the warm, moist environment that can exacerbate symptoms.
• Other Likely diagnoses
  • Contact Dermatitis: This condition occurs when the skin comes into contact with an allergen or irritant, leading to an itchy rash. Common culprits include soaps, detergents, or fabrics that come into contact with the breast area.
  • Seborrheic Dermatitis: Although more commonly associated with the scalp, face, and ears, seborrheic dermatitis can also occur on the breasts, causing an itchy, red rash.
  • Pityriasis Rosea: This condition starts with a single patch (herald patch) followed by an eruption of smaller patches, often on the trunk, which can include the breast area. It's usually accompanied by itching.
• Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
  • Inflammatory Breast Cancer: Although rare, this aggressive form of breast cancer can present with skin changes, including redness, swelling, and itching, without a distinct lump. It's crucial to rule out this condition due to its poor prognosis if left untreated.
  • Paget's Disease of the Breast: This rare form of breast cancer affects the skin of the nipple and, sometimes, the areola. It can cause itching, redness, and scaling, mimicking eczema or dermatitis.
• Rare diagnoses
  • Graves' Disease: This autoimmune disorder that leads to hyperthyroidism can cause skin changes, including a pruritic (itchy) rash, although this is less common.
  • Sarcoidosis: A condition characterized by the growth of granulomas (inflammatory cells) in various parts of the body, which can include the skin, leading to rashes and itching. It's rare for sarcoidosis to present primarily as an itchy rash on the breasts.