A diagnosis of<unk>  is typically made based on the characteristics of the rash. A skin biopsy is usually not required to make the diagnosis but can be helpful to rule out other skin diseases which may resemble<unk> . Extended patch testing may be useful to also rule out allergic contact causes. Other skin diseases that may resemble<unk>  include: * Rosacea * Acne vulgaris * Seborrheic dermatitis * Allergic contact dermatitis * Irritant contact dermatitis * Angular cheilitis
Perioral dermatitis
Tinea capitis
Acroangiodermatitis
Lip licker's dermatitis
Granulomatous facial dermatitis
Eyelid dermatitis
Lacquer dermatitis
Palmoplantar keratoderma