An Open Label Study of an Occlusive Heat Patch in the Treatment of Warts

Background: Local hyperthermia has been demonstrated to be a safe and efficacious treatment for warts. Objective: We aimed to evaluate the safety and efficacy of an epicutaneous heat patch to induce local hyperthermia for the treatment of warts. Methods: We performed an uncontrolled, proof of concept study by applying a novel, reproducible, epicutaneous heat patch to a target wart for 2 hours per day for 12 weeks. There were 15 evaluable participants. An untreated wart was also observed and measured. Wart measurements included the diameter in two dimensions, an investigator global assessment (IGA) score, wart clearance, and monitoring for adverse events as endpoints at week 12 (end of treatment) and week 24 (end of study). Results: No major adverse events were observed. 6.7% of participants reported minor cutaneous events. At week 24, 46.7% of participants achieved complete clearance of both warts. Limitations: The small sample size and lack of independent control in each participant were the main limiting factors. Conclusion: Local hyperthermia delivered by epicutaneous heat patches was well-tolerated, safe, and achieved complete clearance in both treated as well untreated warts in 46.7% of participants at week 24 after 12 weeks of daily use. Clinicaltrials.gov: NCT01746056 J Drugs Dermatol. 2019;18(4):368-373.

Metagenomic Discovery of 83 New Human Papillomavirus Types in Patients with Immunodeficiency.

Several immunodeficiencies are associated with high susceptibility to persistent and progressive human papillomavirus (HPV) infection leading to a wide range of cutaneous and mucosal lesions. However, the HPV types most commonly associated with such clinical manifestations in these patients have not been systematically defined. Here, we used virion enrichment, rolling circle amplification, and deep sequencing to identify circular DNA viruses present in skin swabs and/or wart biopsy samples from 48 patients with rare genetic immunodeficiencies, including patients with warts, hypogammaglobulinemia, infections, myelokathexis (WHIM) syndrome, or epidermodysplasia verruciformis (EV). Their profiles were compared with the profiles of swabs from 14 healthy adults and warts from 6 immunologically normal children. Individual patients were typically infected with multiple HPV types; up to 26 different types were isolated from a single patient (multiple anatomical sites, one time point). Among these, we identified the complete genomes of 83 previously unknown HPV types and 35 incomplete genomes representing possible additional new types. HPV types in the genus Gammapapillomavirus were common in WHIM patients, whereas EV patients mainly shed HPVs from the genus Betapapillomavirus. Preliminary evidence based on three WHIM patients treated with plerixafor, a leukocyte mobilizing agent, suggest that longer-term therapy may correlate with decreased HPV diversity and increased predominance of HPV types associated with childhood skin warts.IMPORTANCE Although some members of the viral family Papillomaviridae cause benign skin warts (papillomas), many human papillomavirus (HPV) infections are not associated with visible symptoms. For example, most healthy adults chronically shed Gammapapillomavirus (Gamma) virions from apparently healthy skin surfaces. To further explore the diversity of papillomaviruses, we performed viromic surveys on immunodeficient individuals suffering from florid skin warts. Our results nearly double the number of known Gamma HPV types and suggest that WHIM syndrome patients are uniquely susceptible to Gamma HPV-associated skin warts. Preliminary results suggest that treatment with the drug plerixafor may promote resolution of the unusual Gamma HPV skin warts observed in WHIM patients.

Maturation of the human papillomavirus 16 capsid.

Papillomaviruses are a family of nonenveloped DNA viruses that infect the skin or mucosa of their vertebrate hosts. The viral life cycle is closely tied to the differentiation of infected keratinocytes. Papillomavirus virions are released into the environment through a process known as desquamation, in which keratinocytes lose structural integrity prior to being shed from the surface of the skin. During this process, virions are exposed to an increasingly oxidative environment, leading to their stabilization through the formation of disulfide cross-links between neighboring molecules of the major capsid protein, L1. We used time-lapse cryo-electron microscopy and image analysis to study the maturation of HPV16 capsids assembled in mammalian cells and exposed to an oxidizing environment after cell lysis. Initially, the virion is a loosely connected procapsid that, under in vitro conditions, condenses over several hours into the more familiar 60-nm-diameter papillomavirus capsid. In this process, the procapsid shrinks by ~5% in diameter, its pentameric capsomers change in structure (most markedly in the axial region), and the interaction surfaces between adjacent capsomers are consolidated. A C175S mutant that cannot achieve normal inter-L1 disulfide cross-links shows maturation-related shrinkage but does not achieve the fully condensed 60-nm form. Pseudoatomic modeling based on a 9-Å resolution reconstruction of fully mature capsids revealed C-terminal disulfide-stabilized "suspended bridges" that form intercapsomeric cross-links. The data suggest a model in which procapsids exist in a range of dynamic intermediates that can be locked into increasingly mature configurations by disulfide cross-linking, possibly through a Brownian ratchet mechanism. Importance: Human papillomaviruses (HPVs) cause nearly all cases of cervical cancer, a major fraction of cancers of the penis, vagina/vulva, anus, and tonsils, and genital and nongenital warts. HPV types associated with a high risk of cancer, such as HPV16, are generally transmitted via sexual contact. The nonenveloped virion of HPVs shows a high degree of stability, allowing the virus to persist in an infectious form in environmental fomites. In this study, we used cryo-electron microscopy to elucidate the structure of the HPV16 capsid at different stages of maturation. The fully mature capsid adopts a rigid, highly regular structure stabilized by intermolecular disulfide bonds. The availability of a pseudoatomic model of the fully mature HPV16 virion should help guide understanding of antibody responses elicited by HPV capsid-based vaccines.

Treatment of recalcitrant warts with occlusive warming patches.

Prior studies have identified local heat therapy as a treatment for recalcitrant warts. We have employed a thermal pad that raises local temperature to 42-43ºC for at least 2 hours in a proof of concept study of three patients with recalcitrant warts. The recalcitrant warts cleared in all three patients beginning in the fourth and fifth weeks after daily treatment with the pads. There were no adverse events. We conclude that the timing of clearance following use of these thermal pads is likely via direct viral killing and immunologic mechanisms. Further controlled trials are underway.

Multiple facial angiofibromas: a cutaneous manifestation of Birt-Hogg-Dubé syndrome.

Birt-Hogg-Dubé syndrome (BHDS) is an uncommon autosomal dominant genodermatosis characterized by a triad of skin tumors--fibrofolliculomas, trichodiscomas, and acrochordons--together with an increased risk of renal tumors and spontaneous pneumothoraces. This report describes multiple facial angiofibromas as the predominant initial manifestation of BHDS. The patient had a total of 41 facial papules removed via shave excision, initially for diagnostic and then for therapeutic purposes; histologic evaluation revealed diagnostic features of angiofibroma in 39 lesions and fibrofolliculoma in only 2. BHDS should be considered, along with tuberous sclerosis and multiple endocrine neoplasia type 1, in the differential diagnosis of multiple facial angiofibromas, particularly when onset is in adulthood.