Pemphigus foliaceus (PF) is a superficial form of pemphigus. Treatment options for PF resemble pemphigus vulgaris, including glucocorticosteroids, immunosuppressive agents and rituximab et al. These treatment approaches can effectively improve the condition but may also be accompanied by high risks of side effects. Therefore, it is crucial to find a safe and effective treatment options for patients with PF. It will not only benefit/be necessary for patients who refuse glucocorticosteroids or immunosuppressive agents treatments, but also for patients who cannot be treated with glucocorticosteroids or immunosuppressive agents. Herein, we reported a case of PF that was treated with apremilast without systemic glucocorticosteroids or immunosuppressive agents. A 54-year-old woman presented with itchy erythema and erosions on the trunk for more than 1 month. The patient applied mometasonefuroate cream without improvement for a duration of two weeks. The past history of diabetes mellitus and atrophic gastritis was reported. Physical examination revealed scattered erythematous macules and erosions on the trunk. No mucosal involvement was observed. The condition was assessed by the pemphigus disease area index and numerical rating scale, with baseline scores of 7 and 8, respectively. Histopathological examination showed acantholysis and intraepithelial blister. Direct immunofluorescence revealed the presence of IgG and Complement 3 deposition between the acanthocytes with the reticular distribution. Based on enzyme-linked immunosorbent assay results, the levels of Dsg1 and Dsg3 antibodies were 28.18 and 0.26 kU/L respectively. The diagnosis of PF was made. This patient was successfully treated with apremilast without systemic glucocorticosteroids or immunosuppressive agents. The patient has continued with apremilast 30mg once daily for maintenance and no adverse events related to apremilast such as gastrointestinal side effects were observed during the 9-month follow-up period. In conclusion, apremilast therapy without systemic glucocorticosteroids nor immunosuppressive agents might provide an effective alternative to management of mild PF without obvious side effect.

OBJECTIVE: Pemphigus vulgaris (PV) and bullous pemphigoid (BP) are two prevalent bullous diseases. Previous studies found that the antibodies of BP could be expressed in the intestinal epithelium and BP was tightly related to inflammatory bowel disease. Therefore, gut microbiota might also play an important role in bullous disease. However, the specific relationship between gut microbiota and bullous diseases remains unknown. Our study aimed to investigate the potential role of gut microbiota in the development and progression of different bullous diseases.
METHODS: We conducted a prospective and observational cohort study at Peking Union Medical College Hospital. Untreated BP and PV patients were recruited, along with healthy controls (HC) who were spouses or caregivers of these patients. Fecal samples were collected, followed by 16S rRNA gene sequencing. Bioinformatics analyses were performed to assess the composition and function of gut microbiota.
RESULTS: A total of 38 HC, 32 BP, and 19 PV patients were enrolled in this study. Compared to HC, BP, and PV exhibited a distinct gut microbiota composition, especially BP. The gut microbiota changes were mainly observed in the phylum Bacteroidetes, Firmicutes, and Proteobacteria. The ratio of Faecalibacterium to Escherichia-Shigella (F/E ratio) had a considerable predictive value (AUC: 0.705) for recognizing BP from PV. The levels of Faecalibacterium and Enterobacter were correlated to the anti-BP 180 and anti-desmoglein 3. Microbial functional prediction revealed elevated activity in pathways related to gut microbiota translocation significantly increased in BP patients, indicating a potential pathogenetic role in BP.
CONCLUSIONS: Our study suggests that the composition of gut microbiota is specific in different bullous diseases and the role of gut microbiota differs. Gut microbiota could help distinguish BP and PV, and might play a role in the pathogenesis of different bullous diseases.