Pemphigus encompasses a group of rare and potentially life-threatening autoimmune bullous diseases. Epidemiological research on pemphigus in China remains limited. This study aimed to analyze the clinical characteristics, diagnostic delay, and initial treatment patterns of patients with newly diagnosed pemphigus at a tertiary center in China. This retrospective study included patients newly diagnosed with pemphigus between January 2020 and December 2024 at the outpatient department of Peking Union Medical College Hospital. Demographic and clinical data were collected and analyzed. A total of 138 patients were included. Pemphigus vulgaris was the most prevalent subtype (68 cases, 49.3%), followed by pemphigus erythematosus (34 cases, 24.6%), pemphigus foliaceus (13 cases, 9.4%), and pemphigus herpetiformis (11 cases, 8.0%). Notably, the diagnostic delay was substantial, with a median of 5.0 (2.0-12.0) months, and 106 patients (76.8%) had been misdiagnosed before a definitive diagnosis was made. Regarding initial treatment, the most frequently used drugs were corticosteroids (104/132, 78.8%), followed by mycophenolate mofetil (33/132, 25.0%), Tripterygium wilfordii Hook F (29/132, 22.0%), minocycline (28/132, 21.2%), and rituximab (24/132, 18.2%). There was no significant difference among the subtypes in the proportion of patients receiving non-steroidal therapies. These findings highlight a significant diagnostic delay and outline evolving treatment patterns for pemphigus in a contemporary Chinese cohort. This information may inform future research directions and health policy decisions for managing this rare disease.

Pemphigus erythematosus, also known as Senear-Usher syndrome, is a rare localized variant of pemphigus foliaceus characterized by superficial blistering in seborrheic regions and immunopathologic overlap with systemic lupus erythematosus. This report describes an otherwise healthy 33-year-old woman with no significant past medical history presenting with widespread erosive plaques and crusted lesions predominantly in seborrheic areas, positive desmoglein-1 antibodies, positive antinuclear antibody (ANA), and histopathology consistent with intraepidermal acantholysis. Our patient demonstrated clinical improvement after systemic corticosteroids and rituximab, with no new bullae formation. This case highlights the diagnostic challenges associated with pemphigus erythematosus, the importance of clinicopathologic correlation, and the potential role of biologic therapy in the treatment of this condition.

Secukinumab is a fully human monoclonal antibody that specifically targets and neutralizes interleukin (IL)-17A, a cytokine typically involved in the mucocutaneous defense against pathogens. Despite its favorable safety profile, serious adverse events such as inflammatory bowel disease, oral pemphigoid-like lesions, and lupus erythematosus have been reported. While widely used for psoriasis treatment, cytokine-based therapies carry a potential risk of triggering autoimmune responses. The precise mechanism by which secukinumab induces pemphigus erythematosus remains unclear but may involve immune dysregulation, autoantibody production, microbiota influences, and genetic susceptibility. We report a case of pemphigus erythematosus occurring in a psoriasis patient during secukinumab therapy, which improved after treatment with methylprednisolone sodium succinate injection, leading to clinical symptom resolution. Clinicians should remain vigilant for potential complications and develop individualized management strategies for patients receiving secukinumab.

Background Pemphigus is a rare autoimmune blistering disorder characterized by involvement of the skin and mucous membranes, primarily due to autoantibodies targeting desmogleins. Emerging evidence has pointed to a potential pathogenic role of antimuscarinic acetylcholine receptor (anti-M-AChR) antibodies and reported a correlation between their titers and pemphigus disease activity. However, data on this association, particularly in relation to different phases of pulse therapy in the Indian context, remain limited. Aim This study aimed to evaluate the correlation between anti-M-AChR antibody titers and pemphigus disease activity at baseline and after Phase I of dexamethasone-cyclophosphamide/azathioprine pulse therapy. Materials and methods This prospective longitudinal observational study included newly diagnosed cases of pemphigus confirmed through histopathology and direct immunofluorescence from April 2019 to March 2021. Pemphigus Disease Area Index (PDAI) scores were recorded, and eligible patients received dexamethasone-cyclophosphamide or dexamethasone-azathioprine pulse therapy as appropriate. Results A total of 29 patients were enrolled: 23 (79%) with pemphigus vulgaris, five (17%) with pemphigus foliaceus, and one (3.4%) with pemphigus erythematosus. Patient ages ranged from 21 to 69 years, with a male-to-female ratio of 0.7:1. By the end of Phase I therapy, 20 patients (69%) completed follow-up. The mean baseline anti-M-AChR antibody titer was 76.48 ± 48.12 U/mL, which decreased to 53.61 ± 30.97 U/mL after Phase I. At that point, PDAI scores showed a moderate correlation with anti-M-AChR antibody levels (r = 0.51, p = 0.02). The reduction in antibody titers from baseline to the end of Phase I was statistically significant (p = 0.05). Conclusions While serum anti-M-AChR antibody titers may not reliably indicate disease activity at the time of diagnosis, their levels appear to reflect changes in disease activity following treatment. This suggests their potential use as a prognostic marker during the course of therapy.

Adjuvant lenvatinib in combination with transarterial chemoembolization (TACE) has demonstrated prolonged disease-free survival in hepatocellular carcinoma patients at high risk of recurrence post-resection. Here, we present the case of a 68-year-old woman who developed serious side effects including pemphigus erythematosus (PE) linked to lenvatinib usage. Initially treated for breast cancer with radical surgery in April 2018 followed by adjuvant therapy, she was later diagnosed with liver cancer, initially mistaken for metastatic breast cancer to the liver. Although systemic treatment for advanced breast cancer was received, the tumor continued to progress and required partial removal of the liver after final evaluation. Subsequent pathology revealed hepatocellular carcinoma combined with risk factors for recurrence, prompting adjuvant therapy with TACE and oral lenvatinib. After three weeks of lenvatinib administration, the patient developed a skin rash diagnosed as PE through skin pathology. Treatment involved oral methylprednisolone, intravenous human immune globulin, and supportive care, resulting in a cure within a month. This unique case highlights the importance of further research not only on lenvatinib but also on monitoring and managing adverse reactions associated with targeted drugs to optimize patient safety and treatment outcomes.