Differential Diagnosis for Red Papules on Edge of Penis with Itching
- Single Most Likely Diagnosis
- Eczema/Dermatitis: This is a common condition that can cause red, itchy papules on the skin, including the genital area. The edge of the penis is a typical location for irritant or allergic contact dermatitis.
- Other Likely Diagnoses
- Psoriasis: Although less common in the genital area, psoriasis can cause red, scaly papules and itching. The location on the edge of the penis could be consistent with inverse psoriasis.
- Lichen Planus: This is an inflammatory condition that can affect the skin and mucous membranes, including the genital area. It often presents with flat-topped, purple papules and can be itchy.
- Balanitis: Inflammation of the glans penis, which can be caused by infection or irritation, and may present with redness and itching.
- Do Not Miss Diagnoses
- Squamous Cell Carcinoma: Although rare, this type of skin cancer can present as a red, scaly patch on the genital area and must be considered, especially in older individuals or those with a history of HPV infection.
- Syphilis: The primary stage of syphilis can cause a painless, red lesion (chancre) on the genital area, which may be accompanied by itching.
- Rare Diagnoses
- Zoon's Balanitis: A rare condition characterized by reddish-brown plaques on the glans penis, often associated with itching and burning.
- Fixed Drug Eruption: A condition caused by an adverse reaction to medication, which can result in red, itchy lesions on the genital area, among other locations.
- Darier's Disease: A rare genetic disorder that can cause red, greasy, and itchy papules in the genital area, although this is less common.