Highlights

Before starting immunotherapy, it is necessary to determine whether it is an adjuvant or alternative for conventional treatment.

BCG vaccination policy depends on the prevalence of tuberculosis in the country, and there is no evidence that BCG revaccination affords additional protection.

In countries where TB is endemic, tuberculin testing, is mandatory before revaccination with BCG to assess the immune status of the patient.

A short term of follow up is not adequate after BCG revaccination, as the incidence of BCG complications such as lupus vulgaris and scrofuloderma is challenging to predict and may need months to years to develop.

The interpretation of TST is required to rule out the presence of latent TB (LTBI), taking into consideration the false positive and negative possibilities.

The frequent injection of PPD as immunotherapy for warts may result in an overstated response. The first dose can boost the subsequent treatments and will lead to difficulty in the interpretation of TST and IGRA when used to diagnose latent TB in a patient receiving PPD immunotherapy.

MWV consists of heat-killed bacilli in a buffer solution, and its use neither needs a prior tuberculin test nor has a specific age group.

In the case of multiple recalcitrant warts, it is preferable to do intralesional injection for the largest one to limit the adverse events due to numerous local injections. Distant lesions will disappear spontaneously after the eradication of the large wart.