Can We Predict the Effectiveness of Intralesional Immunotherapy in Recalcitrant Warts?

Immunotherapy has been used for recalcitrant, large, and multiple warts, although it is difficult to predict which patient will respond. An open interventional cohort trial was conducted in 50 adult patients with recalcitrant multiple, nongenital warts in whom intralesional immunotherapy was given using the Mycobacterium welchii vaccine. The authors determined whether the wart resolution was dependent on the immune response. The response of various types of warts was also compared with the initial immune response. Complete cure was used as a treatment endpoint, which was defined as a lack of recurrence at follow-up of at least 6 months. The majority of patients had palmoplantar warts (54%). A total of 26 patients achieved a clinical cure. The high immune group achieved a higher complete cure rate (60%) as compared with the low immune group (20%) ( P =.008; absolute risk reduction=.44; number needed to treat=3) with a fewer number of sessions ( P =.004). This difference was most marked in palmoplantar warts ( P =.04). Immunotherapy using M welchii is a useful modality in recalcitrant warts in patients who have a test site induration of ≥10 mm, but this does not affect the recurrence rates.