Objective To analyze the clinical manifestations and histopathological features of cutaneous Mycobacterium marinum infections in order to improve the understanding, diagnosis and treatment of this disease. Methods We retrospectively analyzed the clinical manifestations, histopathological features, treatment and outcome of 12 cases of cutaneous Mycobacterium marinum infections diagnosed at the Fifth Affiliated Hospital of Sun Yat-Sen University from 2020 to 2023. Results The average age was 47.3 years. Seafood-induced trauma was a risk factor. Clinical presentations often included unilateral distribution of multiple chronic nodules and plaques on the upper limb, resembling sporotrichosis. Pathological findings included epidermal acanthosis, dermal non-specific inflammatory infiltration, and sometimes with tuberculosis-like granulomas. However, the positive rate of acid-fast staining was low. Nine patients received anti-infective therapy consisting of clarithromycin combined with rifampicin or moxifloxacin. The treatment regimen for other three patients was unknown. All patients experienced resolution of their skin lesions without serious adverse drug reactions, and there were no recurrences during 1-year follow-up. Conclusions Mycobacterium marinum infection should be suspected in patients, especially middle-aged and elderly individuals with a history of trauma or handling seafood, presenting with chronic nodules and plaques, along with pathological findings of tuberculosis-like granuloma or non-specific inflammatory infiltration. These patients can be treated with clarithromycin and rifampicin.

Objective To explore the clinical efficacy and safety of secukinumab in the treatment of childhood generalized pustular psoriasis (GPP) in order to provide a new therapeutic strategy for childhood generalized pustular psoriasis. Methods A retrospective analysis was conducted on the clinical data of 25 children with GPP treated with subcutaneous secukinumab in our department from June 2020 to June 2022. The efficacy was evaluated according to Generalized Pustular Psoriasis Physician Global Assessment (GPPGA) scores, Generalized Pustular Psoriasis Area and Severity Index (GPPASI) scores, Children's Dermatology Life Quality Index (CDLQI) scores, and Depression Self-rating Scale for children (DSRSC) scores. The adverse reactions were also assessed. Results Following secukinumab treatments, the average time of lesion clearance was 3.36±0.99 days. Alleviations of scales and pustules were observed in majority of patients after 2-week treatment. After 28-week treatment, GPPGA score was reduced from 3.56±0.50 at baseline to 0.20±0.50, while GPPASI score was decreased from 34.83±9.24 at baseline to 0.68±1.64. Similarly, both CDLQI and DSRSC scores were decreased 14.96±4.88 to 0.40±0.64 and 11.41±2.54 to 6.64±1.80, respectively. During the course of treatment, upper respiratory tract infections and eczema were observed in 2 cases each. One case each had pain with pruritus on the injection site and headache. No other adverse events were observed. Conclusions Secukinumab is safe and can rapidly improve the erythema, scales and pustules in pediatric generalized pustular psoriasis in addition to the improvements in patients' quality of life and mental health.

Objective To evaluate the clinical efficacy and safety of trephine combined with superficial X-ray radiation and local injection in the treatment of generalized keloids. Methods Five patients with generalized keloids treated at Dermatology Hospital of Southern Medical University from May 2020 to May 2021 were included in this study. VSS scores were compared before and after 12-month treatments with trephine combined with superficial X-ray radiation and local injection of triamcinolone acetonide. Adverse reactions were also assessed. Results After the treatment, all scar tissue became flatter and softer. The VSS scores were significantly decreased from the baseline (4.08±1.11 vs. 9.28±1.52, t=16.30, P<0.001). No severe infections, severe allergy or skin ulcers were observed during the follow-up period. Conclusion Trephine combined with superficial X-ray radiation and local injection of triamcinolone acetonide is effective and safe for keloids.

Objective To investigate the expression and regulatory mechanism of PTPN2 in psoriasis, and to analyze the effects of PTPN2 on psoriasis related immunity in order to determine whether PTPN2 can be used as a potential therapeutic target for psoriasis. Methods R language (3.6.3 version) was used to determine the difference in expression levels of PTPN2 between psoriatic patients and controls, and the receiver operating characteristic (ROC) curve of PTPN2. The Gene Enrichment Analysis software (GSEA) and the Protein Interaction Analysis Database (STRING) were used to determine enrichment pathway of PTPN2 in the psoriasis dataset, and the interaction network of PTPN2 co-expressed genes. The distribution and expression of immune cells in psoriasis datasets were analyzed with CIBERSORT software. The differential expression of immune response pathways and immune response gene sets in psoriasis and their correlation with PTPN2 were analyzed using R language (version 3.6.3). Results PTPN2 mRNA was highly expressed in psoriatic lesions. Immune infiltrating cells, immune response pathways, and immune response gene sets were abnormal in psoriatic lesions. PTPN2 was associated with some immune infiltrating cells, immune response pathways, and immune response gene sets in psoriasis. Conclusions PTPN2 mRNA is highly expressed in psoriatic lesions, and may participate in the occurrence and development of psoriasis by regulating the immune microenvironment.

Objective To evaluate the efficacy and safety of photodynamic therapy (PDT) combined with oral isotretinoin in the treatment of moderate to severe acne. Methods This study was a single center prospective cohort clinical study. Patients with moderate to severe acne who were admitted to the clinic of Guangzhou Institute of Dermatology from January 2019 to July 2022 were enrolled in the study. All patients received ALA-PDT treatment once every other two weeks for 3 times. Patients in the observation group were also given oral isotretinoin at a dose of 10 mg twice-daily. The GAGS score, total number of acne lesions, number of inflammatory lesions, as well as the main adverse reactions were compared between the two groups. Results A total of 49 cases each were enrolled in the ALA-PDT alone and the observation groups. After 4 weeks of treatment, the total skin lesion clearance rate and inflammatory acne clearance rate in the observation group were higher than that in the control group (Z=2.45, P=0.014 for lesion clearance rate; Z=3.33, P=0.001 for inflammatory acne clearance rate).In comparison to ALA-PDT treatment alone, other significant improvements in observation group included GAGS scores (t=3.15, P=0.002), total lesion clearance rate (Z=4.01, P<0.001) and inflammatory acne clearance rate (Z=3.60,P<0.001) after 6 weeks of treatment. The main adverse reactions, including pain (VAS score), incidence of pigmentation and erythema, did not differ significantly between the two groups(P>0.05). No patient in either group dropped out of the trial due to adverse reactions. Conclusions The efficacy of PDT combined with isotretinoin is superior to that of the ALA-PDT treatment alone in the treatment of moderate to severe acne, and there are no significant differences in safety between these two treatments.

Objective To report a case of nodular cutaneous lupus mucinosis and review relevant literature, in order to improve understanding of the disease. Methods We analyzed the clinical and histopathological features of a patient with nodular cutaneous lupus mucinosis. Results A 40 years old man presented with irregular erythema, with scales and partial atrophy on the cheeks, and multiple dense green bean-sized skin-colored nodules on his chest, back, abdomen, and proximal upper limbs. Antinuclear antibody was positive. Pathology of the early nodule showed dermal mucin deposition, and the pathology of later erythema was consistent with typical nodular cutaneous lupus mucinosis, with follicular keratotic plugs, epidermal atrophy, focal liquefaction of basal cells, and perivascular and peri-appendage infiltration of lymphocytes, as well as mucin deposition in the dermis. Direct immunofluorescence showed IgM and C3 positive at basement membrane. There was no renal nor hematologic involvement. The patient was diagnosed with nodular cutaneous lupus mucinosis and responded well to the treatments with systemic glucocorticoid in combination with hydroxychloroquine. Conclusions Although nodular cutaneous lupus mucinosis is a rare disease with unknown pathogenesis, dermatologists can still be able to make early diagnosis if they are familiar with its typical skin features and pathological changes. Dermatologists should strengthen their understanding of and be vigilance towards this disease.

Dermatology, as a compulsory course for undergraduates in clinical medicine, is difficult for the beginner to master by traditional teaching mode due to the variety of diseases, pathogenesis and treatment methods. Starting from skin pathology and collaborating with the ″Learning Connect″ to carry out clinical medicine undergraduate teaching is a good reformed method of teaching for cultivating students' overall thinking. Typical pathological photos and descriptions of diseases are placed on ″Learning Connect″ platform prior to the class. Students can find the corresponding pathological descriptions of disease from the pathological photos during the preview, thereby predicting the nature, arrangement and distribution characteristics, pathogen, pathogenesis and treatment methods of the disease. Teachers and students interact in the classroom, using the dermatopathology as an introduction, integrating the pathogenesis, immunological mechanism, pathophysiology, clinical manifestations and treatment methods of the disease, comprehensively improving students' understanding and memory of the disease. At the end of course, teachers summarize and provide standard answers for definition, pathogenesis and treatment of disease, cultivating students' scientific logical thinking and independent knowledge acquisition ability. This article elaborates on the significance and the methods of combining skin pathology with the ″Learning Connect″ to carry out teaching of dermatology and sexually transmitted diseases, hopefully providing some reference for clinical educators.

We report a case of the meyerson phenomenon around cavernous hemangioma. A 23-year-old male presented with a dark purplish red nodule on the back for over 20 years, and pruritic annular erythema and papules with clear boundaries around the nodule for 1 day. Dermatological examination revealed a dark purplish red nodule about 0.7 cm in diameter on the back, encircled by a 1 cm diameter erythema with papules. Dermoscopic examination showed that several small purplish red cavities with clear boundaries and irregularly distributed dotted blood vessels on the skin lesion under the red background. The histopathology showed that the lesion was covered with squamous epithelium. Large irregular lumens, and sinusoids of different sizes contained red blood cells and fibrin in the superficial and deep dermis. The sinusoids were lined with a single layer of endothelial cells. The patient was diagnosed with the meyerson phenomenon around cavernous hemangioma. After surgical resection, the eczema-like dermatitis subsided. But hemangioma reoccurred without discomfort after more than 1 month. The patient is in follow-up.

A case of Cronkhite-Canada syndrome is reported. A 68-year-old man presented with stomachache and diarrhea for 3 months. The dermatological examination revealed diffuse hair thinning, especially on the frontal region, symmetrical distribution of brown pigmentation covered with green bean-sized maculopapules on the upper and lower lips, hands, and soles. Two-thirds of distal part of the toenails were missing, with rough and uneven dull surface. Pitted edema was observed on the upper eyelids and legs. Laboratory examination showed anemia and hypoproteinemia. Electronic colonoscopy revealed multiple polyps in the colon. Diagnosis: Cronkhite-Canada syndrome. Following high protein nutritional support and symptomatic treatment, anemia and hypoproteinemia were significantly improved. The patient is still under follow-up.

The prevalence of psoriasis is affected by metabolic syndrome. The risk of metabolism is higher in psoriatic patients. The link between these two diseases can be related to similar pathogenesis and genetic susceptibility loci in these diseases. In addition, individuals with psoriasis and metabolic syndrome have similar dietary habits. At present, psoriasis can be treated with traditional treatment and biological agents. Complication of psoriasis with metabolic syndrome can influence both therapeutic regimens. This article reviews the recent progress on the epidemiology, pathogenesis and treatment of psoriasis and metabolic syndrome. Elucidation of the association between psoriasis and metabolic syndrome makes clinicians better understand these two diseases, and provides a new theoretical basis for better prevention and treatment of psoriasis comorbidities.

Malassezia is a group of resident fungi on the skin, which can cause diseases under certain conditions. Among the multiple complicated factors involved in the pathogenesis, secreted proteases of Malassezia are the key factors. Secreted proteases are enzymes capable of hydrolyzing protein peptide bonds, which has special significance in the skin environment enriched in proteins and lipids. So far, 21 species of Malassezia have been identified. Most studies are related to identification and naming, protease activity and pathogenicity of secreted proteases secreted by Malassezia furfur, Malassezia globosa, Malassezia pachydermatis and Malassezia restricta. This paper aims to review the research progress on the secreted proteases of Malassezia furfur, Malassezia globose, Malassezia pachydermatis and Malassezia restricta.

Correct facial analysis is the first step to achieve good results in any facial plastic surgery or facial rejuvenation surgery/procedure. Assessing the corresponding anatomic area of facial aging through facial analysis and precisely designing the surgical plan can achieve and standardize a scientific diagnosis and procedure of the facial rejuvenation. This paper introduces the facial analytical methods, scientifically expounds the anatomical structure and physiological characteristics of aging in each region, and analyzes the effect of application of facial analytical method in facial rejuvenation, in order to provide reference for plastic surgeons to design facial rejuvenation plan.