Dear Editor, Hidradenitis suppurativa (HS) is a chronic inflammatory disease of the hair follicle presenting with recurrent painful nodules, abscesses, fistulas and scarring on the apocrine gland-rich areas. 1 Smoking is recognized as one of the main risk factors in HS development and its prevalence is high, varying between 40% and 90%. 1 Despite some conflicting results, smoking has been linked to severity, 1,2 extension 3 and weaker treatment response. 4,5 Passive smoking refers to the involuntary inhalation of tobacco smoke and appears to be equally responsible for the development of numerous pathologies. However, the prevalence of passive smoking in HS patients and its role in the disease has not been described.A retrospective analysis of HS patients observed in a tertiary hospital, between January 2014 and May 2022, was conducted. Patients declared as nonsmokers were identified, and a telephone survey was carried out to assess passive smoking. Exposure to passive smoking was assessed by selfreport and was defined as living with someone who smokes or working or spending time regularly with people who are smoking. Descriptive statistics were calculated to determine passive smoking prevalence and characterize the active and passive smokers group. In addition, the association between smoking and age at onset and severity of disease (iHS4) was analysed, using the Kruskal-Wallis test. Post hoc pairwise comparisons were conducted using the Dunn test for multiple comparisons with Bonferroni correction. p < 0.05 was considered statistically significant.A total of 266 patients were included, 71.1% (n = 189) smokers and 28.9% (n = 77) declared as nonsmokers. Passive smoking was identified in 53.2% (n = 41) of patients who had declared themselves as nonsmokers at the baseline visit. Unintentional tobacco smoke exposure was mostly recorded at home (87.8%). Characteristics of smokers (active and passive) are summarized in Table 1. The age at disease onset was different in smoking (active and passive) and nonsmoking groups (p < 0.001). No significant statistical difference was found between disease severity (iHS4), p = 0.382 (Table 2).Despite the high prevalence of smokers in HS patients and the common belief that smoking is related to disease development, available studies linking tobacco with HS development are sparse. The prevalence of active smoking in our population (71.3%) is aligned with the previously described. However, global (active and passive) tobacco exposure (86.7%) and particularly the prevalence of passive smoking (53.2% of patients declared as nonsmokers and 15.4% of total) have not been reported so far. In our sample, smoking seems

A hidradenite supurativa é uma dermatose inflamatória crónica e recorrente que se caracteriza pela presença de nódulos inflamatórios e abcessos nas áreas ricas em glândulas apócrinas, que podem evoluir para fístulas supurativas e cicatrizes. Apesar de ser considerada uma das patologias dermatológicas com maior impacto na qualidade de vida dos doentes, é frequentemente subdiagnosticada. A hidradenite supurativa, sobretudo nas suas formas mais graves, associa-se a diversas comorbilidades, pelo que é fundamental adotar uma perspetiva holística e multidisciplinar na gestão destes doentes. A abordagem terapêutica é complexa e desafiante. A terapêutica médica é multifacetada e deve ser adaptada à apresentação clínica e gravidade da doença. A terapêutica cirúrgica deverá ser equacionada como adjuvante à terapêutica médica, em particular nos casos refratários e perante cicatrizes ou mutilação anatómica e/ou funcional. As presentes recomendações pretendem reunir os principais aspetos da abordagem ao doente com hidradenite supurativa e destinam-se a todos os profissionais de saúde envolvidos no seu acompanhamento.

An observational retrospective study in a sexually transmitted disease clinic in Lisbon, found that 5% of patients diagnosed with monkeypox infection presented with primarily mucosal involvement, lacking the typical cutaneous lesions.