Warts – Epidermodysplasia Verruciformis

Epidermodysplasia Verruciformis (EDV) is a very rare genetic condition in which patients become almost covered in warts.  It is an autosomal recessive disorder meaning that both parents must have the trait for EDV in order to have a child with the disease.  On a molecular level, there is a defective gene for EVER 1 and EVER 2 proteins which are responsible for controlling HPV infection.  The cell mediated branch of the immune system is dysfunctional resulting in diffuse spreading of the HPV infection.  Patients are typically infected with multiple HPV types including the common types HPV 1, 2 and 3 as well as the oncogenic types (cancer causing) HPV 5, 8 and 47.  These oncogenic types predispose patients with EDV to squamous cell cancers on their skin.  It is estimated that 60% of all patients with EDV will develop squamous cell cancer.  In childhood, patients with EDV begin to develop warts usually on the dorsum of the hands and arms, which eventually spread to the back, chest and face.  They are flatter than typical warts and usually have a pink or brown color.  These warts become so large that they can become confluent and appear like a large plaque of psoriasis.  It is very important for patients to be counseled about strict sun protection and be followed by a dermatologist very frequently to detect squamous cell cancers early in its course.  EDV lesions are very hard to treat as the patient’s immune system is not assisting in the clearance of these warts.  Liquid nitrogen treatment is the standard but other modalities have been tried.