Differential Diagnosis for Itchy Skin Penis

• Single most likely diagnosis
  • Eczema/Dermatitis: This is a common condition that can cause itchy skin on the penis due to allergic reactions, irritants, or unknown reasons. The penis's skin is sensitive and prone to irritation, making eczema/dermatitis a frequent cause of itchiness.
• Other Likely diagnoses
  • Psoriasis: An autoimmune condition that can cause red, scaly, and itchy patches on the skin, including the penis.
  • Contact dermatitis: Irritation or allergic reaction to soaps, condoms, or other products that come into contact with the penis.
  • Jock itch (Tinea cruris): A fungal infection that thrives in warm, moist areas, such as the groin, and can spread to the penis.
  • Lichen planus: An inflammatory condition that can cause itchy, flat, and purple lesions on the skin, including the penis.
• Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
  • Sexually transmitted infections (STIs) like herpes simplex, syphilis, or genital warts: These conditions can cause itchy skin and lesions on the penis and have significant health implications if left untreated.
  • Penile cancer: Although rare, penile cancer can cause skin changes, including itchiness, and is crucial to diagnose early for effective treatment.
• Rare diagnoses
  • Zoon's balanitis: A rare condition that causes inflammation and itchiness on the head of the penis, often associated with other skin conditions.
  • Fixed drug eruption: A rare condition where certain medications cause skin lesions and itchiness, which can occur on the penis.
  • Hailey-Hailey disease: A rare genetic disorder that causes blistering and itchiness on the skin, including the penis.