Seborrheic dermatitis (SD) is a chronic inflammatory skin condition likely caused by several factors, including overgrowth of the lipophilic yeast Malassezia, increased sebaceous gland activity, and a potential genetic predisposition, whereas Malassezia folliculitis (MF) is a fungal infection of hair follicles. In this case, a 22-year-old male initially presented with erythematous papules on the malar region and was clinically diagnosed with SD. Following partial improvement with topical and oral antifungals, the patient developed new pustular lesions involving the malar and chin regions, raising suspicion of MF. The absence of comedones and cysts helped rule out Acne vulgaris. Potassium hydroxide mount from pustular swabs revealed numerous fungal spores, prompting further investigation. Culture on modified Leeming and Notman agar yielded yeast colonies, which appeared as budding yeast cells under light and fluorescence microscopy with Calcofluor white stain. Molecular identification using PCR for the ITS regions and RFLP analysis confirmed the isolate as Malassezia furfur. This case highlights the clinical progression from SD to MF, underscoring the pathogenic potential of Malassezia and the importance of integrating clinical, microscopic, and culture-based molecular diagnostic approaches for accurate diagnosis and targeted treatment in dermatological mycoses.

Evaluate the combination of sophorolipids and copaiba essential oil in a multifunctional facial formulation aimed at the treatment of conditions such as acne and herpetic folliculitis. Sophorolipids produced by Starmerella bombicola reached 38.37 g/L, predominantly in the lactonic form. Their antimicrobial activity, alone and combined with copaiba oil, was evaluated against Cutibacterium acnes, Staphylococcus aureus, and Staphylococcus epidermidis. The combination reduced the minimum inhibitory concentration against C. acnes from 62.50 to 31.25 μg/mL, demonstrating an additive effect. Antiviral assays showed strong anti-HSV-1 activity, with 95.58% inhibition in the virucidal test and 63.99% in the antiviral assay. Three dermocosmetic formulations were developed, and the optimized formulation achieved 91.45% inhibition of C. acnes and 26.17% antioxidant activity, confirming its multifunctional potential. The application of a formulation combining sophorolipids and copaiba oil shows promising potential for the treatment of skin conditions, demonstrating significant antimicrobial activity against C. acnes as well as adequate physicochemical stability.

We report six human Dermatophilus infections diagnosed in Basel between May 2025 and March 2026. The travel-associated first case developed a pustular rash and conjunctivitis after a stay in Thailand. A second imported case occurred after travel to Indonesia. Four subsequent locally acquired cases presented with genital or inguinal folliculitis-like lesions without reported animal contact. Whole-genome sequencing placed all isolates in a monophyletic cluster within the D. congolensis_A lineage, supporting possible human-to-human transmission. Enhanced surveillance and molecular diagnostics are warranted.

Acne vulgaris pathogenesis involves complex interactions between sebum hypersecretion, follicular hyperkeratinisation, microbial colonisation and inflammatory cascades. While the bacterial microbiome has been extensively studied, the role of the skin mycobiome, particularly lipophilic Malassezia species, remains less clearly defined in acne-prone sites. To evaluate evidence for skin mycobiome involvement in acne pathogenesis, a structured narrative review was conducted in PubMed/MEDLINE and PMC, synthesising findings from 14 cross-sectional studies involving 1650 participants from diverse geographic and ancestry backgrounds. Across sequencing and culture-based studies, Malassezia was the dominant fungal genus on healthy as well as acne-prone skin; species-level data most often identified M. restricta and M. globosa, with occasional reports of M. furfur. Although significant variations were observed in fungal abundance, discrepancies exist between studies due to differences in study design, sampling methods (surface swabs vs. comedone or pustule contents vs. pore strips), culture media (lipid-supplemented vs. standard), molecular target (ITS1 rDNA vs. other loci) and population demographics. Multiple sequencing studies did not detect significant fungal alpha/beta-diversity differences between acne and non-acne skin while confirming Malassezia species dominance. One study highlighted the potential underdiagnosis of Malassezia folliculitis in acne patients, suggesting that misdiagnosis may occur due to overlapping clinical presentations. Future studies should predefine primary outcomes, adjust for multiplicity, report sampling depth (surface vs. follicular), specify fungal rDNA region sequenced, use specific lipid-supplemented media for Malassezia isolation when culturing, co-profile bacteria and fungi, and add systematic clinical assessment of Malassezia folliculitis.

Laryngopharyngeal involvement in Behçet's syndrome is rare but clinically significant because it may cause severe odynophagia, dysphagia, and airway compromise. Optimal treatment has not been established, and irreversible structural sequelae, including laryngopharyngeal stenosis and ulcer scarring, may occur. We describe two men with Behçet's syndrome and symptomatic laryngopharyngeal involvement who showed rapid improvement after infliximab administration following an insufficient response to corticosteroids. In case 1, a 25-year-old man was classified as having suspected Behçet's syndrome based on recurrent oral ulcers, pharyngeal ulceration, arthritis, folliculitis-like skin lesions, and previous episodes of abdominal pain. He developed severe pharyngeal pain and dysphagia due to ulcerative lesions extending from the posterior pharyngeal wall to the esophageal inlet. Intravenous prednisolone resulted in limited endoscopic and symptomatic improvement, whereas infliximab promptly relieved pain and restored oral intake, with no recurrence over 14 years of follow-up. In case 2, a 29-year-old man presented with recurrent fever, oral aphthae, genital ulcers, arthritis, erythema nodosum-like lesions, and pharyngeal and laryngeal mucosal lesions associated with dysphagia. His symptoms and laryngoscopic abnormalities improved promptly after infliximab administration following an inadequate response to prednisolone. These cases underscore the importance of considering early anti-tumor necrosis factor-α therapy in steroid-refractory or relapsing laryngopharyngeal Behçet's syndrome, because progression to irreversible structural complications, including stenosis and adhesion, may necessitate surgical intervention if inflammation is not controlled before permanent damage occurs.

Deucravacitinib, an oral selective tyrosine kinase 2 (TYK2) inhibitor, is an effective treatment for chronic plaque psoriasis. Its use is widening to treat other autoinflammatory conditions, but acneiform eruptions have been increasingly reported. The objective was to quantify the incidence of acneiform eruptions with deucravacitinib and compare odds versus placebo, with exploratory analyses by dose and indication. A search of Medline, Embase, and CENTRAL was made for interventional and observational studies. Primary outcome was incidence of acneiform eruption (acne, folliculitis, dermatitis acneiforme, rosacea). Random-effects meta-analysis pooled proportions and odds ratios (OR) was performed. Of 672 records, 14 studies met inclusion. Overall, 467/5,280 (8.8%) developed an acneiform eruption (acne 71.3%, folliculitis 23.3%, dermatitis acneiforme 3.2%, rosacea 2.1%). Across eight controlled studies, pooled incidence was 6.4% (95% CI: 0.05 - 0.09; I2 = 74.9%). Events occurred in 145/2,539 (5.71%) on deucravacitinib versus 9/1,070 (0.84%) controls; pooled OR 4.56 (95% CI 2.28-9.12; I2=9.4%). Discontinuations for acneiform events were uncommon (7/3,317; 0.21%). Dose- and indication-specific analyses suggested higher odds at greater total daily doses and in psoriasis/inflammatory bowel disease. In conclusion, acneiform eruptions are a frequent cutaneous adverse event with deucravacitinib and occur significantly more often than with placebo yet rarely lead to discontinuation.