Recalcitrant viral warts: results of treatment with the KTP laser.

We report the use of a potassium-titanyl-phosphate (KTP) continuous wave laser in an open study to treat 25 patients with multiple nongenital warts that had failed to respond to conventional therapies. All patients were treated monthly using the 532 nm KTP continuous wave laser and robotic scanner. Twenty patients (80%) responded to treatment with warts: in 12 patients there was complete clearing. Moderate discomfort was reported during the procedure but subsequent morbidity was slight with no evidence of scarring. Follow-up by postal questionnaire revealed that warts recurred in those patients who had stopped treatment early but not in those whose warts had been treated to complete clearance.