Differential Diagnosis for Herpes Simplex on the Nose
- Single most likely diagnosis
- Herpes Simplex Virus (HSV) infection: This is the most likely diagnosis given the presentation of herpes simplex on the nose, as HSV is a common cause of skin lesions in this area, particularly HSV-1 which is known to cause oral and facial lesions.
- Other Likely diagnoses
- Impetigo: A highly contagious bacterial skin infection that can cause lesions on the face, including the nose, and can be mistaken for herpes simplex due to similar appearances.
- Eczema (atopic dermatitis): Can cause skin lesions and may be confused with herpes simplex, especially if the eczema is infected.
- Contact dermatitis: An allergic or irritant reaction that can cause skin lesions on the nose, potentially mimicking herpes simplex.
- Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
- Erythema multiforme: A skin condition that can be triggered by HSV but also by other infections and medications, characterized by target lesions, and can be severe.
- Cellulitis: A bacterial skin infection that can spread rapidly and cause serious complications if not treated promptly.
- Nasal diphtheria: Although rare in areas with good vaccination coverage, it can cause nasal lesions and is potentially life-threatening.
- Rare diagnoses
- Varicella-zoster virus infection (shingles): While more commonly associated with a dermatomal distribution, it could potentially cause lesions on the nose if the ophthalmic branch of the trigeminal nerve is involved.
- Lupus: Systemic lupus erythematosus can cause a variety of skin lesions, including those on the nose, but this would be part of a broader systemic disease.
- Sarcoidosis: A condition that can cause skin lesions, among other symptoms, and could potentially involve the nose, though this is less common.