NEW YORK (Reuters Health) - A targeted heat treatment appears to alleviate bothersome and sometimes painful plantar warts, researchers from China have found.
Plantar warts are skin growths on the soles of the feet caused by the human papillomavirus (HPV), which enters the body through tiny cuts and breaks in the skin. Plantar warts often develop beneath pressure points in the feet, such as the heels or balls of the feet.
Plantar warts can spread if not treated by over-the-counter or doctor-prescribed medications or salves, or by medical freezing, laser, or surgery. However, such treatments vary in their cure or pain-reducing capabilities.
Dr. Xing-Hua Gao, at No. 1 Hospital of China Medical University in Shenyang, and colleagues have found success treating plantar warts using a patented infrared heat-producing device, which heats warts to 44 degrees Centigrade (111 degrees Fahrenheit) without touching patients’ skin.
This approach, called local hyperthermia, cured plantar wart infections in nearly 54 percent of those treated, and reduced wart-related walking pain in 80 percent of the patients who initially had such pain, Gao’s team reports.
Local hyperthermia above 43 degrees Centigrade causes cell death, the researchers note in the Journal of Infectious Diseases. Local hyperthermia at 39 to 48 degrees Centigrade (about 102 to 118 degrees Fahrenheit) has been used to treat some cancerous tumors.
Gao’s team noted previous plantar wart cures using their device at about 45 degrees Centigrade (under 114 degrees Fahrenheit) among patients aware of their treatment.
In their current study, they kept 54 patients “blinded” to their treatment by telling them a red spot would or would not induce heat at their most painful or largest plantar wart.
Twenty-eight patients had one plantar wart held at 44 degrees Centigrade (111 degrees Fahrenheit) on average for 30 minutes. The researchers earlier identified this temperature as bearable without intolerable burning. Treatments ran on 3 consecutive days with follow up on 2 more days 2 weeks later. Another 26 patients of similar age and plantar wart infections had sham treatments.
After 3 months, 15 of the 28 heat-treated patients (nearly 54 percent) had no remaining sign of the treated wart, compared to only 3 of the 26 sham-treated patients (less than 12 percent). Twelve heat-treated individuals with initial pain reported decreased pain while walking, compared to only 2 sham-treated individuals.
If this approach proves effective in further studies, it “might be generally available in two or three years,” Gao noted in an email to Reuters Health.
SOURCE: The Journal of Infectious Diseases, published online March 3, 2010