Flat wart in Adult
The warts arise from benign strains of HPV and are not known to cause cancer. They are contagious and spread easily over the body. Transmission is commonly via person-to-person contact or via fomites. Existing skin trauma (ie, cuts, scratches, burns, eczema) predisposes patients to contracting HPV. A person with flat warts may spread the warts to a different part of the body (autoinoculation) through trauma to the skin such as scratching or shaving.
Children, young adults, and immunocompromised patients are most susceptible. Widespread or extensive warts are often presenting signs of an immunocompromised state. Warts may be more numerous and more difficult to treat in immunocompromised patients. Excessive sun exposure can lead to exacerbation.
While warts are normally self-limited in children, they may be difficult to treat in adults. Longer periods of treatment are usually necessary for adults.
B07.8 – Other viral warts
240539000 – Flat wart
Differential Diagnosis & Pitfalls
- Common wart
- Seborrheic keratosis
- Actinic keratosis
- Lichen planus
- Lichen nitidus
- Molluscum contagiosum
- Epidermodysplasia verruciformis – A genetic disorder characterized by diffuse flat warts and a high potential for squamous cell carcinoma transformation. Consider this diagnosis when evaluating a patient with widespread flat warts.
- Multinucleate cell angiohistiocytoma