In recent years, great progress has been made in the research on the pathogenesis of pruritus, and many new targeted therapeutic drugs have been developed, mainly including small-molecule drugs or biological agents targeting signal transduction pathways involved in the pathogenesis of pruritus, such as neurokinin-1 receptor, tropomyosin-related kinase A, transient receptor potential vanilloid 1, transient receptor potential melastatin 8 channels, interleukin 31, etc. Some of these drugs have shown good efficacy and safety in the treatment of pruritus in a variety of skin diseases, providing more options for patients with pruritus, especially those who are resistant to traditional drug treatment. This review summarizes research progress in the above small-molecule drugs and biological agents targeting signaling pathways involved in pruritus, in order to provide more options for pruritus treatment.

Glucagonoma is a rare neuroendocrine tumor of α cells of the pancreas. The tumor excessively secretes glucagon and causes glucagonoma syndrome.70%-90% of patients with glucagonoma will develop necrolytic migratory erythema (NME). We reported a patient of glucagonoma syndrome who was presented to the dermatology outpatient clinic with a 2-year-history of recurrent erythema and scaling on the skin migrating throughout the body. A skin biopsy was performed and resulting features matched with NME, whilst imaging examinations suggested a soft tissue density tumor present in the tail of the pancreas with somatostatin receptor expression and laboratory tests found an elevated levels of serum glucagon. After the diagnosis was confirmed, the patient was treated with surgical resection of the glucagonoma and the skin eruptions resolved rapidly in 4 days. Meanwhile, we reviewed relevant literature published in recent years and summarized its clinical characteristics in order to improve its understanding by clinicians, including clinical manifestations, laboratory and imaging examinations, diagnosis and treatments.

Rare skin diseases are various in kinds facing many challenges and difficulties in diagnosis and treatment. Recently, the diagnosis of rare skin diseases has improved continuously. Molecular diagnostic tool, a representation of the next generation sequencing technology, can effectively assist the accuracy of clinical diagnosis for rare diseases. The research and development of orphan drugs and gene therapy have made continuous breakthroughs and progress, bringing hope to patients with rare skin diseases. It is crucial to establish scientific disease management system of the disease, layered referral networks, and the standardized clinical pathways to improve the diagnosis and treatment level of rare skin diseases.This article provides a brief overview of the progress in the diagnosis and treatment of rare skin diseases and explore the future possibilities.

There are many kinds of rare skin diseases, but the research into the diagnosis and treatment of rare skin diseases is relatively scarce. In recent years, the rare skin diseases team has made a series of accomplishments, including establishing the professional committee of Rare Skin Disease Committee of China Alliance for Rare Diseases, establishing China's first Medical Care Alliance for Rare Skin Diseases, launching two national collaborative projects, promoting the project of improving the diagnosis and treatment of rare diseases supported by the Central Special Lottery public welfare Fund, exploring the multidisciplinary diagnosis and treatment model of skin rare diseases, holding academic conferences, and compiling professional books on rare skin diseases. In the future, we will further improve the remote consultation model of rare skin diseases, develop artificial intelligence assisted diagnosis system of rare skin diseases, carry out high-quality clinical research, and improve the overall diagnosis and treatment level of rare skin diseases in China, for the sake of benefiting more patients.

Rare diseases are characterized by extremely low incidence rate and small number of patients in total. The drugs used to treat rare diseases are called orphan drugs. Currently, 450 kinds of rare skin diseases have been identified, most of which lack in effective treatments. Supported by the policy-making from the country and pushed by all sectors of the society, drugs for rare skin diseases have been emerging continuously recently in China. This paper reviews the current accessibility of the orphan drugs for skin rare diseases that have been approved in China and in other countries and regions for a better understanding of rare dermatosis and orphan drugs for the diseases.

Annular elastolytic giant cell granuloma(AEGCG) is a rare granulomatous skin condition. We present a case of a 67-year-old man with annular plaques on the face, neck, shoulder, back and upper limbs, and mildly pruritis exceeding one year. Histopathological examination demonstrated granulomatous inflammatory infiltration of lymphocytes, histiocytes and multinuclear giant cells in the middle and the upper dermis, with more local eosinophils. Elastic fiber staining showed that elastic fibers were absent in granuloma area and were engulfed by multinucleated giant cells. Based on the clinical and histopathological findings, a diagnosis of AEGCG was made. The etiology and pathogenesis of this condition are unclear, and atypical manifestations of non-exposed areas can also occur.It is usually related to systemic diseases lacks specific treatment at present.

Psoriasis is a chronic inflammatory skin disease with significant physical and psychological burdens. The interplay between the innate and adaptive immune systems is thought to contribute to the pathogenesis; however, the details of the pathogenesis remain unclear. In addition, reliable biomarkers for diagnosis, assessment of disease activity, and monitoring of therapeutic response are limited. Metabolomics is an emerging science that can be used to identify and analyze low molecular weight molecules in biological systems. During the past decade, metabolomics has been widely used in psoriasis research, and substantial progress has been made. This review summarizes and discusses studies that applied metabolomics to psoriatic disease. These studies have identified dysregulation of amino acids, carnitines, fatty acids, lipids, and carbohydrates in psoriasis. The results from these studies have advanced our understanding of: (1) the molecular mechanisms of psoriasis pathogenesis; (2) diagnosis of psoriasis and assessment of disease activity; (3) the mechanism of treatment and how to monitor treatment response; and (4) the link between psoriasis and comorbid diseases. We discuss common research strategies and progress in the application of metabolomics to psoriasis, as well as emerging trends and future directions.
Humans ; Psoriasis/drug therapy* ; Skin/metabolism* ; Biomarkers/metabolism* ; Metabolomics/methods*

Objective:To investigate the effect of narrow-band ultraviolet B (NB-UVB) phototherapy on the incidence of cutaneous carcinoma, herpes zoster and cataracts in patients with psoriasis vulgaris.Methods:A telephone follow-up was conducted among patients with psoriasis vulgaris receiving NB-UVB phototherapy at the Department of Dermatology, Peking Union Medical College Hospital from January 1, 2003 to December 31, 2019. The incidence of cutaneous carcinoma, herpes zoster and cataracts was investigated, and their incidence density and 95% confidence intervals ( CIs) were calculated. Subgroup analyses were performed according to the cumulative number of NB-UVB radiation (≤ 100 times, 101 - 300 times, > 300 times), cumulative radiation energy (≤ 100 J/cm 2, > 100 - 500 J/cm 2, > 500 J/cm 2), and average radiation frequency (≤ 1.5 times/week, > 1.5 times/week). Univariate Cox′s proportional hazards regression analysis was conducted to analyze differences in the incidence density of cutaneous carcinoma, herpes zoster, and cataracts between the groups, and the results were expressed as hazard ratios ( HRs) and their corresponding 95% CIs. Results:A total of 160 patients with psoriasis vulgaris completed the follow-up, including 99 males (61.9%) and 61 females (38.1%). Their ages (median [ Q1, Q3]) were 39 (28.3, 54.8) years, the cumulative numbers of NB-UVB radiation were 129.5 (52, 291) times, the cumulative radiation energy was 226.3 (71.1, 688.9) J/cm 2, and the average radiation frequencies were 1.57 (1.37, 1.83) times/week. No cutaneous carcinoma occurred during the follow-up of 1 288.87 person-years (7.77 [5.11, 9.92] years) ; herpes zoster occurred in 4 cases during the follow-up of 1 273.85 person-years (7.68 [5.11, 9.88] years), and the estimated incidence density of herpes zoster was 31.4/10 000 person-years (95% CI: [11.8 - 83.5]/10 000 person-years) ; cataracts occurred in 8 cases during the follow-up of 1 264.67 person-years (7.72 [4.84, 9.83] years), and the estimated incidence density of cataracts was 63.3/10 000 person-years (95% CI: [31.7 - 126.2]/10 000 person-years). No significant differences were observed in the incidence density of herpes zoster or cataracts among subgroups with different cumulative numbers of NB-UVB radiation, cumulative radiation energy and average radiation frequencies (all P > 0.05) . Conclusion:The incidence of herpes zoster or cataracts may not be affected by the cumulative number of NB-UVB radiation, cumulative radiation energy or average radiation frequency in patients with psoriasis vulgaris.

Bullous pemphigoid (BP) can be comorbid with a variety of immune diseases, such as immune skin diseases (psoriasis, vitiligo, alopecia areata and various other immune bullous diseases) , immune digestive diseases (inflammatory bowel disease, primary biliary cirrhosis) , autoimmune thyroid diseases, autoimmune rheumatic diseases (rheumatoid arthritis, dermatomyositis, scleroderma and systemic lupus erythematosus) , immune renal diseases (immune nephropathy, renal allograft rejection) and acquired hemophilia A. The above comorbidities markedly affect the quality of life of and treatment options for patients. This review elaborates on currently reported immune diseases associated with BP and their concomitant mechanisms.

Objective: To evaluate the application value of ultrasound and dermoscopy in the precise preoperative evaluation of basal cell carcinoma (BCC) , and to analyze the association of high-frequency ultrasound and dermoscopic findings with pathological recurrence risk of BCC. Methods: Clinical data were collected from 33 outpatients with confirmed BCC in the Department of Dermatology, Peking Union Medical College Hospital between April 2016 and December 2018, and high-frequency ultrasonographic and dermoscopic findings from 36 BCC lesions were analyzed. The lesions were classified into high-risk and low-risk groups based on pathological findings. Statistical differences in ultrasound and dermoscopic characteristics between high-risk and low-risk BCC groups were analyzed by using Fisher′s exact test, and the correspondence between high-frequency ultrasonographic and dermoscopic features of BCC was analyzed by calculating the simple matching coefficient. Results: Of the 36 BCC skin lesions, 4 were high-risk lesions and 32 were low-risk lesions. Ultrasonographic features of the high-risk and low-risk lesions overlapped markedly, and no significant differences were observed between the high-risk and low-risk lesions with regard to the shape, boundary, internal echo, hyperechoic spots, or posterior echo (all P > 0.05) . However, 24 (75.0%) low-risk lesions were confined to the dermis, whereas 4 high-risk lesions involved the subcutaneous tissue, and there was a significant difference between the high-risk and low-risk BCC groups with regard to the distribution of BCC (P = 0.008) . In 5 BCC lesions, ultrasound could identify small easy-to-ignore lesions or deep and invisible lesions besides obvious lesions. There were no significant differences in dermoscopic features between high-risk and low-risk groups. However, none of spoke-wheel area, milky-red structureless area, milia-like cysts, comedo-like openings and rainbow pattern was observed in 4 high-risk BCC lesions. The simple matching coefficient between enhanced hyperechoic spots in the lesion observed by ultrasound and milia-like cysts under a dermoscope was 36.1%, and the simple matching coefficient between discontinuous hyperechoic echo in the epidermis on ultrasonography and ulcer/erosion under a dermoscope was 75.0%. Conclusion High-frequency ultrasound and dermoscopy both provide important information for preoperative evaluation of risk of BCC lesions, and high-frequency ultrasound can identify easy-to-ignore hidden lesions in clinical practice.