A study of the effectiveness of chemosurgery with trichloroacetic acid for Japanese cedar pollenosis in terms of the chemical mediator levels in the nasal discharge and results of nasal provocation testing

Interrupting aerosol spread and nasal acquisition of SARS-CoV-2 with topical trichloroacetic acid

The devastating effects of the coronavirus designated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have merited many approaches to combat COVID-19. Since it is transmitted largely by fine droplets and aerosols, air defense with suitable ventilation and mask use might be enhanced by attacking the virus and its likely main point of invasion, the nasal mucosa. We recommend formal clinical trials employing topical trichloroacetic acid (TCA), which successfully blocks the nasal entry point for airborne allergens and to be curative for the early stages of viral infections of the oral mucosa. TCA chemically redesigns the nasal and nasopharyngeal epithelia to in effect remove receptors and cell, allowing SARS-CoV-2 viral attachment. TCA fits the ideal category for medication, being inexpensive, readily available, easy-to-use, and proven to be safe for suggested use. We postulate its potential efficacy in SARS-CoV-2 infection and urge consideration of clinical trials. Local delivery of TCA in the form of contact application directly to the nasal cavity may have a preventive effect, potentially neutralizing virus entry and subsequential virus spread to the lower respiratory tract, especially for those at high risk. In addition, TCA may diminish the local viral load and its replication potential in those newly infected.

COVID-19: Topical agents and therapeutic prevention of nasal viral acquisition

Since the spread of SARS-CoV-2 became a pandemic, the number of cases has been continuously growing worldwide. Numerous recommendations and suggestions have been published to prevent the acquisition and spread of the SARS-CoV-2, especially to protect health workers and front-line caregivers. SARS-CoV-2 is transmitted by aerosol, rendering air defense with suitable ventilation and adequate mask use pivotal. Recently, locally applied antiseptic, antiviral, or structure competitive receptor blockers were suggested to attack the virus at its main point of invasion, the nasal mucosa and nasopharynx. We discuss the most plausible and safe ideas to reduce viral load at the point of entry, and subsequently the spread of SARS-CoV-2 to the lower respiratory tract, lungs, and other organs. In addition, we analyze the value and recommend clinical trials employing topical trichloroacetic acid (TCA), a substance well known from dermatologic and cosmetic procedures. It has been proven to successfully block the nasal entry for airborne allergens, preventing the development of allergic rhinitis and asthma, and to be curative for early stages of viral infections entering through the oral mucosa. For SARS-CoV-2, TCA in a single, short-time application is expected to remodel the nasal and nasopharyngeal epithelia, eliminating both the receptors and cells responsible for viral entry and subsequent viral spread to the lower respiratory tract. Moreover, this may have therapeutic benefits for those recently infected by reducing local viral replication. Such procedures are cheap, safe, and can be conducted in almost every setting, especially in regions with inadequate financial and logistic resources.

Topical Corticosteroid Pretreatment Mitigates Cellular Damage After Caustic Injury to the Nasal Upper Airway Epithelium

BACKGROUND

Topical corticosteroids are currently employed to reduce established airway inflammation; their prophylactic use might help limit cellular damage against harmful stimuli.

OBJECTIVES

To determine the effects of a prophylactic topical application of budesonide (BD) on an in vivo nasal epithelium injury model induced by trichloroacetic acid (TCA).

METHODS

C57Bl/6 mice were exposed to intranasal TCA topical application. Three groups received topical intranasal BD, saline solution, or no intervention prior to a single topical exposure to TCA. Controls were not exposed to TCA. Whole nasal cavity coronal sections were analyzed at 1, 3, and 6 days postinjury at tissue and cellular levels using histopathological analysis, immunofluorescent staining, and fresh tissue RNA microarray analysis.

RESULTS

Prophylactic topical corticosteroid exposure protected the nasal epithelium from acute damage, maintaining epithelial thickness and cell survival. Six days following TCA exposure, epithelial and cellular changes were less pronounced on the BD-treated group compared to all exposure groups. The microarray analysis was used to evaluate the gene transcripts in all treatment groups. Ciliary tip protein, Sentan, and submucosal protein S100b were identified as potential factors in epithelial airway protection; immunofluorescent staining corroborated their presence and location within the respiratory epithelium.

CONCLUSION

Topical corticosteroid treatment to the nasal epithelium can mitigate several of the early deleterious effects of acute epithelial damage in experimental airway injuries caused by TCA. These findings suggest a novel, direct cytoprotective effect of corticosteroids on the nasal epithelium, and the potential of expanding the use of prophylactic periprocedural topical corticosteroids for respiratory epithelial tissues.