天疱瘡

Pemphigus comprises autoimmune blistering diseases with heterogeneous clinical presentations, but pre-referral provisional diagnoses in regional tertiary dermatology practice have been less well characterized. We retrospectively reviewed 35 consecutive patients diagnosed with pemphigus at Toyama University Hospital, a regional tertiary dermatology center in Japan, between January 2011 and May 2026. Final diagnoses were established using clinical, histopathological, immunopathological, and serological findings. We extracted referral characteristics, pre-referral provisional diagnoses, final diagnoses, disease severity, and dates of symptom onset and referral visit from medical records. The median age was 69 years, and 20 patients (57.1%) were female. Final diagnoses were pemphigus vulgaris in 15 patients (42.9%), pemphigus foliaceus in 10 (28.6%), paraneoplastic pemphigus in 3 (8.6%), intercellular IgG/IgA dermatosis in 3 (8.6%), pemphigus herpetiformis in 2 (5.7%), pemphigus vegetans in 1 (2.9%), and unclassified pemphigus in 1 (2.9%). Only 10 patients (28.6%) had pemphigus recorded as the pre-referral diagnosis; other pre-referral diagnoses included impetigo, Behçet's disease, refractory stomatitis, dermatitis/eczema, pemphigoid, and drug eruption. Exploratory cosinor analysis suggested possible annual variation in the interval from symptom onset to referral visit, with longer intervals around winter and shorter intervals around summer. By mapping pre-referral diagnoses to final pemphigus diagnoses, this study highlights heterogeneity in diagnostic subtypes and referral pathways through which pemphigus reaches regional tertiary dermatology care.

Immune checkpoint inhibitors (ICIs) can precipitate autoimmune bullous diseases, among which bullous pemphigoid (BP) is uncommon but has significant clinical implications. We report a 72-year-old man with poorly differentiated gastric adenocarcinoma and liver metastases who developed generalized pruritic erythema after the 4th cycle of sintilimab, followed by tense blisters after the 8th cycle. Upon admission (January 2025), over 30% of his body surface area (BSA) was affected, accompanied by pruritus that impacted his sleep. Histopathology showed eosinophilic cell infiltration within the epidermis and mild spongiosis. Edema was observed between collagen fibers in the papillary dermis, accompanied by a small number of lymphocytes and histiocytes. Moderate (+++) mixed inflammatory cell infiltration was observed in the superficial dermis, primarily consisting of lymphocytes (approximately 60%) and eosinophils (approximately 30%), with a small number of neutrophils (approximately 10%). Direct immunofluorescence (DIF) revealed IgG and C3 along the basement membrane zone (BMZ). Serum autoantibodies demonstrated significantly elevated BP180 (392.01 RU/mL) and low BP230 (9.29 RU/mL), while desmoglein-1 (8.38 U/mL) and desmoglein-3 (5 U/mL) were negative/low, supporting BP rather than pemphigus. The rash met the CTCAE (Common Terminology Criteria for Adverse Events) v5.0 criteria for Bullous dermatitis, Grade 3, with concomitant Pruritus, Grade 3. Daily intravenous methylprednisolone 60 mg was initiated, leading to cessation of new blister formation within 7 days and improvement in pruritus. Sintilimab was discontinued during treatment and resumed after BP was brought under control (approximately 1 month later); the patient has maintained remission for more than 12 months since resuming Sintilimab treatment, and no recurrence has been observed. The temporal association with PD-1 blockade, objective clinicopathologic confirmation, and lack of strong alternative culprits support a possible causal relationship. Early biopsy, DIF, and targeted serology enable timely CTCAE-guided management and informed decision-making for pausing or rechallenging PD-1 therapy.

Pemphigus vulgaris (PV) is a rare, potentially life-threatening autoimmune blistering disorder characterized by intraepidermal acantholysis caused by IgG autoantibodies directed against desmoglein 1 and 3. Although most cases are idiopathic, certain medications, including antibiotics, have been implicated as potential triggers in susceptible individuals. We report the case of a 61-year-old man with a history of nonischemic cardiomyopathy, chronic kidney disease, and substance use disorder who developed widespread flaccid bullae six days after initiation of intravenous ceftriaxone for a suspected urinary tract infection. Histopathologic examination demonstrated suprabasal intraepidermal acantholysis with intraepidermal vesicles containing neutrophils and eosinophils, along with preservation of the basal epidermal layer in a characteristic "row of tombstones" pattern, findings highly suggestive of PV. Ceftriaxone was promptly discontinued, and the patient was treated with high-dose systemic corticosteroids, resulting in marked clinical improvement. Ceftriaxone-induced PV is an exceedingly rare adverse reaction, with few cases reported in the literature. The proposed pathogenesis involves drug-induced neoantigen formation or stimulation of pathogenic autoantibody production in genetically predisposed individuals. Early recognition of drug-induced PV is essential, as continued exposure may result in extensive mucocutaneous involvement, secondary infection, and increased morbidity. Prompt withdrawal of the offending agent and initiation of immunosuppressive therapy are critical for improving clinical outcomes.

BACKGROUND AND AIMS: This study investigated the association between adherence to the EAT-Lancet diet-a predominantly plant-based, anti-inflammatory dietary pattern-and the severity of pemphigus vulgaris (PV), a rare autoimmune blistering disease. METHODS: This cross-sectional study was conducted in an Iranian population with a high incidence of PV and included 138 newly diagnosed patients. Disease severity was assessed using the Pemphigus Disease Area Index (PDAI). RESULTS: The findings revealed a significant inverse association between adherence to the EAT-Lancet diet and PV severity. After adjus[tment for potential confounders, including age, sex, BMI, corticosteroid use, and caloric and carbohydrate intake, higher adherence to the diet remained consistently associated with markedly lower odds of severe PV (OR: 0.10; 95% CI: 0.02-0.40; p for trend = 0.001), suggesting that dietary patterns may influence disease activity and progression. CONCLUSION: Although this cross-sectional study has several important limitations-including the inability to establish temporality, potential reverse causation, and a small number of severe cases-the observed association between higher adherence to the EAT-Lancet diet and lower pemphigus vulgaris severity should be interpreted as hypothesis-generating. These findings may justify further research in larger longitudinal cohorts or dietary intervention trials, but they do not provide sufficient evidence to support dietary modification as an adjunctive clinical strategy for PV management at this stage.