OETDK.

Background: Hidradenitis suppurativa (HS) is a chronic inflammatory disorder of the pilosebacous unit in the apocrine gland rich anatomical regions. It presents with recurrent painful nodules, abscesses, and sinus tracts, often with scarring and reduced quality of life. The Dept. of Dermatology of the University of Debrecen (DDUD) serves as a referral center and has recorded rising consultations in recent years along with improved service development and greater awareness. Aim: To describe and compare HS patients’ data at the DDUD concerning disease’s diagnostic characters, life habits, clinical parameters, comorbidities, treatments based on the severity of the disease defined by International Hidradenitis Suppurativa Severity Score System (IHS4). Patients and Methods: Cross sectional data collection and analysis was conducted at the DDUD in 1 January to 30 April 2025. Survey included all patients once, with HS attended the clinic. From UDMed electronic records the following data were extracted: age, sex, Fitzpatrick skin type, family history, smoking status, body mass index (BMI), comorbidities, disease onset, age at diagnosis, age at first tertiary care, number of physicians before diagnosis, prior and current therapies, disease severity. Based on the IHS4 index patients were grouped as mild-moderate (IHS4≤10) and severe (IHS4>10), and the groups were compared on the listed parameters. Results: We analyzed and compared over 100 patients in the two groups. There was significantly higher number of patients in severe group, where male patients were represented in a significantly higher proportion. In this severe group significantly higher amount of patients presented with Hurley III stage and they received significantly higher number of surgeries in the past years. The biologicals were also used significantly more frequently in the severe group than in the mild-moderate group. Conclusion: HS is a debilitating disease, where irreversible changes may occur in case of significant delay in diagnosis and lack proper treatment. Thus the earlier the patients are referred to a center, earlier they are provided the adequate management. Recognizing this need our clinic became an attractive management center in less than a decade, providing available solutions for hundreds of patients in HS.

Témavezető: Dr. Gàspàr Krisztiàn

Introduction:Cutaneous melanoma (CM) is an aggressive yet immunogenic tumor, accounting for disproportionate mortality. PD-1/PD-L1 therapy shows promise, but variable response and different PD-L1 scoring systems (Complex Positive Score [CPS], Melanoma Scoring [MEL]) complicates evaluation. Alternative pathway of tumor immune evasion via MHC-I suppression remains underexplored.Objectives:● Assess CPS–MEL correlation● Evaluate MHC-I/B2M expression and relation to tumor-infiltrating lymphocytes (TILs)● Compare MHC-I levels in primary vs. metastatic CMMethods:We analyzed 25 advanced CM cases (mean age 55; mixed sites; BRAF+). Twelve patients received pembrolizumab (3 neoadjuvant); 7 responded (mean survival 79.7 months). Immunohistochemistry used PD-L1, CD8+, MHC-I, B2M antibodies. Scoring: MHC-I/B2M (Strong >75%, Moderate 25–75%, Negative <25%); TIL density graded 0–3. PD-L1 scoring: CPS formula vs. MEL (positive tumor cells/total tumor cells). Statistical tests included Spearman correlation, paired t-test, Wilcoxon, Tukey.Results:● PD-L1 scoring: CPS strongly correlated with MEL (Pearson R = 0.946), supporting interchangeability.● MHC-I/B2M status: 84% showed MHC-I complete or partial loss; B2M loss co-occurred in these cases, suggesting their close relationship. Loss was related with invasion depth.● TIL distribution: MHC-I+ areas had significantly higher CD8+ TIL density (Spearman r = –0.44) compared with MHC-1- region.● Primary vs. metastatic: Significant MHC-I decline in metastases (p = 0.0017), especially lymph node lesions.Discussion & Conclusion:Our findings highlight MHC-I loss may serve a potential alternative immune escape mechanism in CM which may lead to ineffective immunotherapy. CPS and MEL scoring systems are interchangeable, streamlining diagnostic workflows. MHC-I loss, linked to possible B2M deficiency and reduced TIL density, correlates with deeper invasion and metastasis, underscoring its role in progression-linked immune evasion. We conclude that MHC-I may be an useful biomarker additional to PD-L1 assessment for optimal patient management. Future molecular studies will target the mechanism of B2M mutations which may cause MHC-I under-expression.

Témavezető: Dr. Chang Chien Yi Che

Background: Skin tumors are frequently localized on the lower leg, where the proximity of the tibia, tight soft tissues, and thin subcutaneous layer create surgical challenges. Reconstruction of defects following the removal of tumors larger than a few centimeters in diameter often presents difficulties. Several dermatologic surgical techniques are available, and the selection of the most appropriate method depends on multiple factors, including the size, clinical appearance and precise localization of the tumor. Previous biopsy and histological findings also influence the choice of technique. Additionally, the patient’s general condition, comorbidities, and regular medications must be considered, as these can affect postoperative regeneration and wound healing.Aims of the Study: We examined patients with skin tumors of various clinical appearances localized on the lower leg. Our aim was to analyze their data and evaluate the healing process following different surgical approaches. Histological results and postoperative outcomes were assessed, and the operated areas were monitored during follow-up.Patients and Methods: We analyzed data from seven patients with various skin lesions treated using different surgical and non-surgical techniques. Patients were followed until complete recovery. Histological findings, wound-healing outcomes, and recurrence rates were recorded and compared with data from the literature.Results: The following surgical techniques were applied among the seven patients: simple excision with primary closure, excision with flap reconstruction, excision with autografting, necrotectomy in cases of extensive skin and soft tissue defects, and negative pressure wound therapy. For superficial lesions, shave biopsy and cryotherapy were used. Histological diagnoses included pyogenic granuloma, precancerous lesions, and basal cell carcinoma, among others. All wounds healed successfully, and no recurrences were observed during the follow-up period.Conclusion: Skin tumors of the lower leg are often detected late by patients. Early recognition and excision are strongly recommended. Impaired circulation, the unique anatomical features of the lower leg, and the proximity of bone can complicate healing. In accordance with the literature, the surgical approach should always be individualized. Regular follow-up is essential for early detection of recurrence and optimal long-term outcomes.

Témavezető: Dr. Szabo Eva

Introduction: Heme oxygenase-1 (HO-1), encoded by HMOX1, is a stress-inducible enzyme producing antioxidant and cytoprotective metabolites. In skin, it is activated by ultraviolet radiation, reactive oxygen species, and inflammatory signals. Sebocytes face a highly oxidizable lipid environment, and acne lesions contain neutrophil-derived oxidative stress and lipids such as arachidonic acid. As HMOX1 proved inducible in SZ95 sebocytes, we examined its functional role in these cells. This study provides a detailed analysis of HO-1 expression, regulation, and function under oxidative and inflammatory stimuli.Methods: HO-1 localization was assessed by immunohistochemistry in biopsies from acne vulgaris, rosacea, atopic dermatitis, and healthy skin. SZ95 sebocytes were treated with sebum-associated lipids (palmitic, stearic, oleic, and arachidonic acid), and HO-1 expression was analyzed by quantitative PCR and Western blotting. Total ROS production was assessed following arachidonic acid or heme exposure, with or without the ROS inhibitor N-acetylcysteine. The cytoprotective function of HO-1 was evaluated in HMOX1-silenced sebocytes exposed to hydrogen peroxide treatment, and its potential involvement in lipid synthesis was analyzed using Oil Red O staining. Statistical analysis was performed using ANOVA followed by post-hoc tests, with significance defined at p<0.05.Results: Arachidonic acid produced the strongest increase in HMOX1 expression (9.4-fold; p<0.01) and was the only lipid that elevated HO-1 protein levels. Immunohistochemistry demonstrated strong HO-1 staining in basal sebocytes of acne lesions, whereas healthy skin, rosacea, and atopic dermatitis showed no detectable signal. Arachidonic acid significantly increased ROS levels at all measured time points (p<0.01), and N-acetylcysteine prevented both ROS accumulation and HO-1 induction (p<0.05). Silencing HMOX1 markedly reduced sebocyte viability under oxidative stress (p<0.001), while lipid content remained unchanged (p>0.05).Conclusion: HO-1 is selectively induced in sebocytes by arachidonic acid through a ROS-dependent mechanism and is present in acne but absent in other inflammatory skin diseases. By enhancing sebocyte survival without affecting lipid production, it acts as an acne-specific redox-protective pathway. These results highlight HO-1 as a meaningful marker of oxidative stress in acne and suggest that its activity may influence sebocyte resilience during inflammation.

Témavezető: Dr. Dull Katalin

Background Hymenoptera venom allergy is the most common cause of anaphylaxis in adults. The only disease-modifying therapy of it is allergen immunotherapy (AIT), during which the patient is desensitized and prevented from the development of allergic reactions in case of getting re-stung. Although AIT protocol is well-defined, unexpected challenges in therapy may emerge. Manufacturing shortage of venom preparations may be one of them. There has been little evidence in the literature about what an allergologist can do in such situations in order to provide safe and effective management of AIT patients.AimsDuring shortage of AIT medication, following the investigators’ decision, a lower than standard maintenance dose in a less frequent manner than usual was provided to patients. The study aimed to determine the effect of decreasing dose and frequency of AIT on the effectiveness and safety of the treatment. Patients and MethodsIn the study, we collected data from 60 patients undergoing wasp AIT who received reduced doses of venom at fewer frequencies between November 2024 – May 2025. Adult patients were included who had already been on wasp AIT for at least 3 months. The study assessed the results of skin prick tests (SPT), venom-specific IgE, and Basophil Activation Test (BAT) obtained from patients at the time of their diagnosis (T0), the beginning of the AIT at the start of modified dose and frequency (T1), and after 6 months of treatment (T6). ResultsAssessing the above-mentioned variables throughout the course of the regular as well as the modified AIT, we found no changes in specific IgE levels and BAT results, but a significantly improving tendency in SPT. Results indicated that there was no decline in the efficacy of the treatment. There was no evidence for adverse events during or between the modified AIT detected in these patients. ConclusionsIn case of unpredictable challenges in AIT, it is better to provide less medication dose less frequently, rather than to cancel the further treatment, jeopardizing the whole outcome of the intervention. When AIT is altered, the patient is exposed to hazarding the beneficial outcome of AIT, as well as being threatened by the possibility of developing unwanted reactions after insect bites while having no protection against them. In case of shortage of medication, it is rather recommended to modify AIT than to cancel it permanently.

Témavezető: Dr. Gáspár Krisztián

Atopic dermatitis (AD) and psoriasis are immune-mediated inflammatory skin diseases with a high prevalence. Our research group previously conducted a comprehensive analysis of the expression levels of all 11 IL-1 family members in lesional skin samples from AD patients. This analysis identified significantly elevated expression of IL-33, IL-18 and IL-36β compared with healthy skin. The current study aimed to compare cytokine expression profiles in AD and psoriasis samples, and determine which cytokines are already detectable in the early stages of atopic inflammation (represented by perilesional AD skin).The protein-level expression of IL-1 family cytokines was examined by immunofluorescence in the epidermis of eight lesional and nine perilesional AD skin biopsies, as well as eight psoriasis biopsies. Eight healthy skin samples from gland-poor (GP) regions served as controls. Furthermore, the IL-1 family was investigated at the gene level in AD and psoriasis samples using a publicly available RNA-seq database.Our analysis revealed that IL-33 expression was elevated only in AD samples, while IL-36β in both AD and psoriasis. On the other hand, the expression of multiple IL-1 subfamily members, all IL-36 subfamily cytokines (IL-36α, IL-36β, IL-36γ and IL-36RA) and IL-37 were significantly higher in the psoriasis samples. No significant differences were found between the two disease groups for IL-18, IL-38 or IL-1RA. Importantly, none of the examined cytokines exhibited increased expression in perilesional AD skin. These findings indicate that increased expression of several IL-1 family members is characteristic primarily of psoriasis, IL-36β in both, while IL-33 appears to be the principal cytokine with elevated expression in AD. Consequently, IL-33, IL-18 and IL-36β may represent a promising therapeutic target in AD, whereas multiple members of the IL-1 cytokine family could serve as potential therapeutic targets in psoriasis.

Témavezető: Dr. Kapitány Anikó és Prof. Dr. Szegedi Andrea