Cryotherapy VS. Nitric-zinc Complex in the Treatment of Plantar Warts.

Cryotherapy With Liquid Nitrogen and Nitric-zinc Complex in the Treatment of Plantar Warts. Randomised Controlled Trial.

Plantar warts are benign skin lesions caused by human papillomavirus (HPV).There are several treatment methods for this illness, but none of them can heal all patients. Cryotherapy using liquid nitrogen is one of the most common local treatments. In this study, we will compare the effectiveness of cryotherapy with liquid nitrogen with the association of organic acids and nitric acid (nitric-zinc complex). In addition, as secondary objectives have been defined: 1) know the number of applications necessary for each treatment to achieve the complete resolution of the plantar wart, in order to compare the healing times between each treatment and establish which treatment is faster, 2) analyze the influence of the HPV biotype, the location of the lesion and the time of evolution in the response to the different treatments, and 3) Compare the ultrasound signs of plantar warts with the ultrasound signs of healthy skin after the resolution of the process.

A randomized controlled clinical trial is proposed. The recruitment of patients will be carried out by including the sample of those patients who have diagnostic confirmation of plantar wart in the Chiropodology and Surgery Service of the University Podiatry Clinic of the Complutense University of Madrid, consecutively, between November 2020 and the date when the estimated sample size is reached.

Participants in the trial will be assigned with equal probability to each treatment arm, based on their consecutive inclusion in the study. Subsequently, the treatment allocation will be determined by a random code generated by the Epidat 4.1 program using random permuted blocks. The treatment used will be evident both for the participant and for the research podiatrist responsible for the intervention. However, the primary result will be confirmed by the microbiological study carried out by the Department of Microbiology of the Complutense University of Madrid, which does not know any data about the patient or the treatment group to which it was initially assigned.

Inclusion Criteria:

• Subjects older than 12 years.
• Patients diagnosed with recalcitrant or non-recalcitrant plantar wart.

Exclusion Criteria:

• Diagnosis of Diabetes Mellitus.
• Peripheral vascular disease.
• Patients with an immune system disorder or in immunosuppressants treatment.
• Peripheral or central neuropathy.
• Coagulation disorders.
• Raynaud's disease or some alteration of the perception of cold or heat.
• Alterations in healing for wounds or in the synthesis of collagen.