Intralesional purified protein derivative of tuberculin versus intralesional mycobacterium W vaccine in treatment of recalcitrant extragenital warts: A randomized, single-blinded, comparative study

Mycobacterium w - a promising immunotherapeutic intervention for diseases

Immunomodulating agents interact with the immune system and alter the outcome of specific immune processes. As our understanding of the immune system continues to evolve, there is a growing effort to identify agents with immunomodulating applications to use therapeutically to treat various diseases. Mycobacterium w (Mw), a heat-killed mycobacterium, is an atypical mycobacterial species that possesses strong immunomodulatory properties. Mw was initially evaluated as an immune-therapeutic against leprosy, but since then Mw has generated a lot of interest and been studied for therapeutic applications across a host of diseases, such as pulmonary tuberculosis, tuberculous pericarditis, sepsis, lung cancer, and more. This article summarizes a large body of work published in the past five decades, describing various aspects of Mw and its potential for further therapeutic development.

Systematic Review of Intralesional Therapies for Cutaneous Warts

Intralesional therapies are used for recalcitrant warts, but no Food and Drug Administration-approved treatment exists nor is there consensus regarding the most efficacious therapy. Therefore, this systematic review aims to summarize efficacy and adverse events reported in 62 randomized controlled trials (RCTs) of intralesional therapies for cutaneous warts. The most studied intralesional therapies included measles, mumps, rubella (MMR) vaccine (n = 24 studies), purified protein derivative (PPD) (n = 19 studies), vitamin D3 (n = 15 studies), and Candida antigen (n = 14 studies). Most studies included adult and pediatric patients or adults alone, with only 4 studies on pediatric patients alone. MMR vaccine was the most studied treatment (n = 853 patients). MMR had a complete response rate of 27-90%. The next most common treatment, PPD, had a complete response rate of 45-87%. Other treatments included Candida antigen and vitamin D3, with complete response rates of 25-84% and 40-96%, respectively. The most frequent side effects were injection-site reactions and flu-like symptoms. This systematic review represents a useful summary of intralesional therapy RCTs for clinician reference. This study also highlights the lack of large multi-institutional RCTs, despite many patients being treated for this widespread problem.

Efficacy of Cryotherapy Combined With Intralesional Purified Protein Derivative (PPD) Versus Intralesional PPD Monotherapy in the Treatment of Multiple Common Warts

INTRODUCTION

Intralesional antigen immunotherapy represents a promising therapeutic approach for the treatment of different types of warts, particularly if multiple and/or recalcitrant.

AIM

to investigate the efficacy and safety of combined cryotherapy with intralesional purified protein derivative (PPD) immunotherapy in the treatment of multiple common warts.

METHODS

Fifty patients were randomly divided into two groups (25 patients each): Group A: receiving intralesional PPD immunotherapy for the largest wart, while group B: receiving cryotherapy for all warts plus intralesional PPD for the largest wart. Treatments were performed every 2 weeks for a maximum of four sessions. Photographs were taken at baseline and at each visit and clinical response was evaluated by the reduction in number and size of warts. Adverse effects were recorded.

RESULTS

There was a significant reduction in size and number of warts in both groups (P < .001), with no significant difference between the two groups. Complete clearance of the lesions was observed in 48% of patients in group A and 44% in group B (P = .39). Higher rates of near complete/complete response were achieved after fewer sessions (2, 3 sessions) in group B (P = .002). Blistering was common after cryotherapy. Higher rate of hypopigmentation was noticed after combined treatment than after PPD monotherapy (56%, 8% respectively; P < .001), which resolved gradually.

CONCLUSION

Both intralesional PPD alone and combined cryotherapy with PPD are safe and effective in clearing of common warts. Cryotherapy may be a successful adjunct to intralesional PPD immunotherapy that helps in reducing the number of treatment sessions.The study protocol was registered at ClinicalTrials.gov with ID: NCT04288817.