BACKGROUND: In Western nations, hidradenitis suppurativa (HS) typically affects the apocrine gland-bearing skin of people of African origin, women, smokers, and individuals with obesity. The clinical characteristics of HS in Korea and Japan, however, are reportedly different from those in the West. We therefore hypothesized that wet earwax is associated with HS because most East Asian people are genetically predisposed to produce dry earwax. METHODS: The medical charts of 53 Japanese patients with HS were reviewed retrospectively. RESULTS: Unlike the results of surveys conducted in Western nations, most of our patients were men (72%), whose buttocks were the most commonly affected site. Apocrine gland-bearing areas, such as the axilla, were affected less often. The proportion of HS patients with wet earwax was 51%, which was substantially higher than that found in the general Japanese population. Moreover, when patients with gluteal HS were excluded, the proportion of patients with wet earwax became even higher (68%). CONCLUSIONS Although the etiology of HS is unknown, our survey indicated that HS in apocrine gland-bearing skin, such as the axillary and anogenital areas, may be associated with wet earwax. As this study was conducted in a limited clinical setting, a nationwide, multicenter survey is warranted to clarify the clinical characteristics of HS in Japan.

Background: Individuals with axillary osmidrosis suffer detrimental effects to their psychosocial functioning. In Asian nations, major operations for axillary osmidrosis include subdermal excision (open surgery) and suction-curettage (closed surgery). Objective: The aim of this meta-analysis was to determine which of these two procedures is most favorable in terms of safety and efficacy. Methods: According to the Preferred Reporting Items for Systematic Reviews and Metaanalyses (PRISMA) guideline, we searched electronic databases for articles published in English, Japanese, Korean, and Chinese languages. Fixed-effects model meta-analyses of odds ratios (OR) and 95% confidence intervals (CI) were conducted, and the I2 was used to assess heterogeneity. Complication rates, recurrence/ineffectiveness rates, and patient satisfaction data were extracted and compared between open and closed surgeries. Results: Our search yielded 8 articles that include 1,179 patients; 560 underwent open surgery, and 619 underwent closed surgery. Our meta-analysis revealed that suction-curettage had a significantly lower risk of acute adverse events than open excision (OR, 0.15; 95% CI, 0.07~0.32), whereas open excision was significantly superior to suction-curettage for recurrence/ineffectiveness rate (OR, 2.90; 95% CI, 1.37~6.15). Patient satisfaction was equally high with both treatments (OR, 1.58; 95% CI, 0.69~3.60). Conclusion Since surgical treatments for axillary osmidrosis have been performed mostly in East Asian nations, it was meaningful to review articles published in four languages. This meta-analysis revealed that closed surgery was safer but less effective than open surgery. However, both patient groups expressed high satisfaction with the outcomes. Our results may be helpful for deciding surgical treatment options.