Eosinophilic folliculitis due to wearing protective gear in citizens volunteering for sanitation services during the COVID-19 pandemic - an original epidemiological, clinical, dermoscopic, and laboratory-based study.

Background: An association between wearing protective gear and eosinophilic folliculitis has not been reported. We aimed to investigate such during the COVID-19 pandemic.

Methods: In three outpatient clinics, we hand-reviewed records of all patients having consulted us during a Study Period (90 days) in the early phase of the pandemic. Our inclusion criteria for Study Subjects were: (i) clear clinical diagnosis, (ii) dermoscopic confirmation, (iii) differential diagnoses excluded, (iv) eosinophilia, (v) protective gear worn during sanitation services, (vi) temporal correlation, (vii) distributional correlation, (viii) physician-assessed association, and (ix) patient-assessed association. Control Periods in the same season were elected.

Results: Twenty-five study subjects fulfilled all inclusion criteria. The incidence was significantly higher than in the control periods (IR: 3.57, 95% CI: 1.79-7.43). Male predominance was significant (P < 0.001). Such for patients in the control periods were insignificant. Study subjects were 21.2 (95% CI: 11.0-31.4) years younger than patients in the control periods. For the study subjects, the distribution of erythematous or skin-colored folliculocentric dome-shaped papules and pustules were all compatible with body parts covered by the gear. Lesional biopsy performed on two patients revealed eosinophilic dermal infiltrates within and around the pilosebaceous units. Polarized dermoscopy revealed folliculitis with peri-/interfollicular vascular proliferation. Lesion onsets were 6.4 (SD: 2.1) days after wearing gear. Remissions were 16.7 (SD: 7.5) days after ceasing to wear gear and treatments.

Conclusions: Wearing protective gear in volunteered sanitizing works could be associated with eosinophilic folliculitis. Owing to the significant temporal and distributional correlations, the association might be causal.