Immunotherapy using purified protein derivative in the treatment of warts: An open uncontrolled trial.

BACKGROUND: Warts are known to clear spontaneously with the development of cell-mediated immunity (CMI) to the virus. Purified protein derivative (PPD) of tuberculin bacilli has been used as a non-specific stimulant of CMI to achieve this outcome.

AIM: To study the effect of PPD in the treatment of warts.

METHODS: Patients with difficult to treat warts were selected for immunotherapy. Each patient received 2.5 TU of PPD intralesionally in a few warts. A total of four sessions were given at 2 weekly intervals and patients were followed up for 6 months after the last dose.

RESULTS: Sixty-one patients were recruited of which 55 completed 6 months follow up and were available for analysis. Of these, 25 had verruca vulgaris, 18 had verruca plana and 12 had plantar warts. Forty-two (76%) patients showed complete clearance after four sessions while the remaining 13 (24%) patients were non-responders. One patient developed a recurrence after total clearance during the follow-up period. Adverse effects were erythema, edema and pain at the site of injections.

LIMITATIONS: As this was an uncontrolled trial, there is no comparison with a non-intervention group. Also, a Mantoux test was not done due to practical difficulties.

CONCLUSION: Immunotherapy with PPD is helpful in the treatment of cutaneous warts.