Differential Diagnosis for Bumps on Skin after Sun Exposure
- Single most likely diagnosis
- Polymorphic Light Eruption (PMLE): This is the most common condition causing bumps on the skin after sun exposure. It is characterized by an itchy, bumpy rash that appears after sun exposure, typically on the arms, legs, and chest. The condition is thought to be an allergic reaction to sunlight.
- Other Likely diagnoses
- Sunburn: Direct damage to the skin from UV radiation can cause bumps, redness, and blistering. While sunburn itself is not typically characterized by "bumps," the healing process can lead to peeling and bumps.
- Solar Urticaria: A rare form of physical urticaria that occurs in response to sunlight, leading to itchy hives or bumps on the skin.
- Phototoxicity: Certain medications or substances can cause a reaction when exposed to sunlight, leading to bumps, blisters, or rashes on the skin.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- Malignant Melanoma or Other Skin Cancers: While not directly causing bumps after sun exposure, any new or changing skin lesions should be evaluated for the possibility of skin cancer, as early detection is crucial for treatment and survival.
- Lupus: Systemic lupus erythematosus can cause a photosensitive rash, and while it's not the first consideration for bumps after sun exposure, missing a diagnosis of lupus could have significant health implications.
- Rare diagnoses
- Actinic Prurigo: A rare condition characterized by itchy, bumpy lesions that occur after sun exposure, more common in certain populations like those of Native American descent.
- Hydroa Vacciniforme: A rare photodermatosis that presents with blistering lesions after sun exposure, typically in children.
- Chronic Actinic Dermatitis: A condition causing persistent inflammation of the skin in response to sunlight, leading to thickening and bumps on the skin, more common in older adults.