Inactivated Sinovac-CoronaVac vaccine (Sinovac Life Sciences, Beijing) for coronavirus disease 2019 (COVID-19) has been used in many countries. However, its immunogenicity profile in immunosuppressed dermatological patients is lacking. This prospective observational case-control study compared the humoral immune response between adult dermatological patients receiving systemic immunosuppressive therapies (n = 14) and those who did not (n = 18); excluding patients with HIV infection, cancer, non-dermatological autoimmune conditions, previous COVID-19 infection, and positive anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) IgG prior to vaccination. The subjects were advised to withhold methotrexate for 1 week after each vaccine dose while continuing other therapies unadjusted. Anti-SARS-CoV-2 IgG antibody, surrogate neutralizing antibody (sNAb), and seroconversion rates (calculated from the percentages of participants in the group with positive sNAb) were used to assess immunogenicity. We found that participants using azathioprine, cyclosporin, mycophenolate mofetil, or prednisolone ≥ 10 mg/day had a lower level of serum anti-SARS-CoV-2 IgG antibody and sNAb than those received methotrexate ≤ 10 mg/week, prednisolone < 10 mg/day, or biologics (i.e., secukinumab, ixekizumab, omalizumab). Patients who received methotrexate ≤ 10 mg/week, prednisolone < 10 mg/day or the biologics had a similar immunogenicity profile to those without immunosuppressive therapies. Despite the lack of statistical significance, a reduction of humoral immune response was observed among the study participants who used ≥2 immunosuppressants or pemphigus patients. Our findings suggest that a subset of patients with immune-mediated skin conditions respond poorly to the vaccine despite having low-level immunosuppression. These patients could benefit from vaccines that trigger a greater level of immunogenicity or booster doses.

Alopecia areata (AA) is an autoimmune disease of the hair follicles. It is characterized by a well-defined non-scarring alopecic patch or patches that may extend to the entire scalp or lead to total body hair loss. Due to its unpredictable clinical course, AA causes substantial psychological harm. Despite the high prevalence of this disease and extensive research, its exact pathomechanism is unclear, and current treatments have a high relapse rate that has deemed AA incurable. Over the past few decades, researchers have investigated multiple potential factors that may help alleviate its pathogenesis and provide effective treatment. Given its complex immunopathogenesis, AA is considered an autoimmune disease with multiple factors. This review gathers current evidence that emphasizes molecular mechanisms, possible causative etiologies, and targeted immunotherapies for AA. Understanding its underlying mechanisms may shed light on new strategies to effectively manage AA in the future.

BackgroundSyphilitic alopecia (SA), which mimics other types of alopecia, is an uncommon manifestation of secondary syphilis. Trichoscopic features may facilitate its diagnosis. However, studies on SA and its trichoscopic characteristics remain limited.ObjectiveTo investigate the epidemiological, clinical, and trichoscopic findings and laboratory results, treatment, and outcomes of SA in Thai patients as well as to comprehensively summarize all trichoscopic features of SA through a systematic review.MethodsData on patients diagnosed with SA between December 2010 and December 2021 were obtained from their medical records and analyzed retrospectively. A systematic review of trichoscopic data, both from our institution and from studies registered in the PubMed, MEDLINE, and Embase databases, was conducted. A descriptive summarization was performed to comprehensively study the trichoscopic features of SA.ResultsOf the 205 patients with secondary syphilis, 23 patients with SA (symptomatic SA: 20, essential SA: 3) were included. The mean age was 27.6 ± 8.8 years, and male predominance was noted. The moth-eaten pattern was the most common SA presentation, and the parieto-occipital scalp was the most commonly affected area. All patients with SA achieved significant hair regrowth within 3 months of antibiotic therapy. Trichoscopic images were available for 20 patients with SA from our institute and were included in the systematic review. Fourteen articles provided information on 21 patients. Overall (N = 41), 26 (63.4%), 8 (19.5%), and 7 (17.1%) patients had moth-eaten alopecia, diffuse alopecia, and mixed alopecia, respectively. The most frequent trichoscopic finding was short regrowing hairs (78%), followed by decreased hair per follicular unit (75.6%), and empty follicles (51.2%). Unique features included flame hairs, bent tapering hairs, reddish-brown background, and brown rings around the perifollicular areas, each described in one case. However, the results were based only on case reports and small case series.ConclusionsGiven the progressively increasing frequency of SA, trichoscopic examination may be valuable when SA is suspected in patients with idiopathic alopecia; however, our findings are quite non-specific. The absence of exclamation mark hairs may help in the diagnosis of SA. Further comparative studies on other types of alopecia are required to determine the most useful diagnostic features.