Dermoscopic features of actinic keratosis

Actinic keratosis (AK) is a keratinocytic neoplasm that typically develops on sun‐damaged skin of elderly individuals. Only a few reports so far have described the dermoscopic diagnostic features of AK, mainly focusing on facial non‐pigmented AKs. A typical feature of facial non‐pigmented AK is a composite pattern named “strawberry pattern”, characterized by a background erythema/red pseudonetwork consisting of unfocused, large vessels located between the hair follicles, associated with prominent follicular openings surrounded by a white halo. Dermoscopic characteristics of pigmented AK on the face include multiple slate‐gray to dark‐brown dots and globules around the follicular ostia, annular‐granular pattern and brown to gray pseudonetwork. Recognizing specific dermoscopic features of AK can be useful in guiding the clinician in the differential diagnosis of AK with melanocytic skin lesions such as LM and non‐melanocytic lesions. Histopathologic examination should be performed whenever clinical and/or dermoscopic differential diagnosis is inconclusive.     

慢性光化性皮炎的组织病理变化

对５１例慢性光化性皮炎（ＣＡＤ）５７个皮肤活检标本的组织病理变化进行了分析，结果表明其组织病理变化呈多形性，为迟缓性变态反应，自早期或活动期的湿疹样皮炎至晚期皮肤Ｔ细胞淋巴瘤样谱系改变。上述不同组织病理变化与同一标本石蜡包埋块中异倍体或二倍体的发现无明显关系，但ＣＡＤ与皮肤恶性淋巴瘤（ＣＭＬ）皮损石蜡包埋块中异倍体的发生率相似，表明ＣＡＤ与ＣＭＬ有某些类同或相关联。     

日光性角化病研究进展

日光性角化病的发病与炎症反应、氧化应激、免疫抑制等有关, 其组织病理表现为表皮结构异常和角质形成细胞发育不良,其他非侵入性的成像方法对诊断该病也有重要意义。治疗方法包括局部药物、光动力、冷冻、激光等。本文对日光性角化病的流行病学、发病机制、临床和组织学特征、诊断及治疗进行综述。     

Expression of p53 and p16 in actinic keratosis,bowenoid actinic keratosis and Bowen's disease

Introduction Bowen's disease (BD) and bowenoid actinic keratosis (bAK) have traditionally been differentiated according to the presence or absence of dysplasia in the follicular epithelium. p16 has been suggested to be a useful tool to make the differential diagnosis between BD and AK and as a marker of bad prognosis. Materials Five biopsies of BD, five of AK and five of bAK where stained for p53 and p16. Results All lesions showed positive immunostaining of p53, affecting to the lower two thirdss of the epidermis in BD and bAK, and only the basal layer in non‐bAK. All the BD and bAK cases were positive for p16, showing a similar immunostaining pattern, whereas no staining was observed in non‐bAK. Discussion and conclusion These findings suggest a common pathogenic mechanism for BD and bAK. bAK might have worse prognosis than AK. p16 might not be useful as a tool for differential diagnosis between AK and BD because bAK and BD show an extremely similar immunohistochemical pattern.     

What is actinic prurigo in Britain?

Actinic prurigo (AP) belongs to the group of idiopathic photodermatoses sharing a predilection for occurring more commonly in females, and there is much controversy as to whether it is only a more severe form of polymorphous light eruption (PMLE) or whether it is a distinct entity in its own right. The condition is characterised by intensely itchy papules, plaques and nodules, along with excoriations and scars usually starting before puberty, and predominantly involves the sun-exposed areas although it may also affect covered sites. Seasonal exacerbations at the beginning of spring with improvement in the fall are typical, although the lesions frequently do not clear completely in the winter. The disorder may run a chronic course and persist into adulthood, but often spontaneous resolution occurs in late adolescence. Diagnosis is predominantly based on the clinical features, cutaneous irradiation tests and histology often being normal or non-specific. HLA typing has also been performed in both PMLE and AP patients, showing a strong association between HLA-DR4, in particular with the DRB1*0407 subtype, and AP; no HLA association has been found in PMLE. This HLA association is likely to be of pathogenic significance and strongly suggests a critical role for MHC-restricted antigen presentation in the development of photosensitivity AP.     

光化性扁平苔藓1例

报告1例光化性扁平苔藓。患者女，80岁。右耳前皮肤棕褐色斑疹伴做痒1年余。皮肤组织病理检查显示角化过度、表皮萎缩，基底细胞液化变性伴明显的色素失禁．真皮浅层中等量淋巴细胞带状浸润或片状分布于毛细血管周围，未见异形细胞。     

Radiation therapy for extensive actinic keratosis

Actinic keratosis in the most common premalignant keratotic tumour of sun-exposed skin. A 66-year-old man developed a large actinic keratosis on his scalp, which did not respond to conventional treatment. Fractionated radiotherapy with a cumulative dose of 28 Gy resulted in complete remission without relapse during a 14-month follow-up. In older subjects in whom conventional treatment fails, low-dose fractionated radiation therapy is an effective alternative method.     

Diagnosis and treatment of actinic prurigo

Actinic prurigo (AP) is an idiopathic photodermatosis that affects mainly the mestizo population in Latin America. It has an early onset, a slight predominance in women, and affects the sun-exposed areas of the skin, causing erythematous papules and lichenified plaques secondary to intense and chronic pruritus. Lesions can be induced by both ultraviolet A (UVA) and ultraviolet B (UVB). An association with several human leukocyte antigen (HLA) alleles has been reported. AP is unique among all photodermatoses in its remarkable response to thalidomide. In the past the microscopic features of AP have been considered as nonspecific; however, the constant finding of dense lymphocytic inflammatory infiltrates and the immunogenetic features of AP support the existence of an immunologic mechanism in its pathogenesis.     

Guidelines for the management of actinic keratoses

These guidelines stemmed from a consensus meeting held by the British Photobiology Group (BPG) in 1999. Following this meeting one of the authors (J.M.M.) was invited to draw up guidelines for the management of actinic keratoses by the British Association of Dermatologists Therapy Guidelines and Audit Subcommittee. Relevant evidence was sought using the search terms 'solar keratosis' and 'actinic keratosis' in Medline from 1966 onwards. Additional and earlier literature was reviewed on the basis of references within post-1966 publications. All articles of apparent relevance were reviewed independently of the nature of the publication. The quality of the evidence elicited has been indicated. The National Ambulatory Medical Care Survey (U.S.A.) was used for further data on topical chemotherapy. Papers were reviewed and discussed by the contributors to the BPG Workshop (see Acknowledgments). Recommendations are evidence based where possible. Strength of recommendation is coupled with quality of evidence. Strength of recommendation includes consideration of apparent cost-benefit and practical considerations. Quality of evidence reflects the nature of the trial structure that provides data of efficacy.     

Diagnosis and treatment of chronic actinic dermatitis

Chronic actinic dermatitis, synonymous with the photosensitivity dermatitis and actinic reticuloid syndrome, presents as a dermatitis and/or a pseudolymphomatous eruption. Abnormal photosensitivity to ultraviolet (UV) and often visible radiation is a feature. Many patients also have multiple contact allergens. Histopathologic features vary, with a spectrum from mild dermatitis to pseudolymphomatous (reticuloid) features. The essential tests to make the diagnosis and to guide advice on avoidance of the responsible wavelengths and any contact allergens are phototesting and patch testing. Chronic actinic dermatitis can be regarded as a disorder of increased susceptibility, for reasons that remain uncertain, to develop delayed-type allergic responses to both endogenous photoallergens and exogenous allergens. Treatment consists of detailed advice on sunlight and allergen avoidance (guided by the results of investigations), topical corticosteroids, and emollients. When these measures are insufficient alone, systemic immunosuppressives may be considered: systemic prednisolone for acute exacerbations or azathioprine if systemic treatment is required for more than a few weeks.     

慢性光化性皮炎43例临床分析

目的：探讨43例慢性光化性皮炎诱发因素、临床和光生物学特征及治疗情况。方法：回顾性分析43例慢性光化性皮炎患者临床资料。结果：43例患者，皮损分布于暴光部位，急性发作表现为红斑、丘疹、渗出、结痂，病情迁延后出现浸润肥厚的苔癣样丘疹、斑块。形态学和组织学上类似假性淋巴瘤。光生物学试验中79．1％患者对UVB敏感，93．1％对UVA敏感，光斑贴试验证实了8例患者的光敏物。避光和去除光敏物，局部外用糖皮质激素、口服烟酰胺、维生素B族和抗组胺药。严重病例口服小剂量泼尼松反应停与免疫抑制剂可控制病情。结论：光生物学试验是诊断慢性光化性皮炎的重要依据，避光和去除光敏物是治疗关键。     

Cyclosporin A in chronic actinic dermatitis

Two patients with chronic actinic dermatitis received considerable benefit from the administration of cyclosporin A. The drug was initially given at 5 mg/kg/day and then reduced to about 4 mg/kg/day. No side effects have been registered so far. The scanty literature is reviewed. Cyclosporin A may be a useful adjunct to the armamentarium in this difficult-to-manage disorder.     

A case of actinic prurigo in Thailand

Actinic prurigo is a separate entity from the polymorphous light eruption that affects American Indians. It has been reported mainly from North and South America, with only few reported cases from Britain or Asia. We report a case of actinic prurigo in a Thai girl who showed cheilitis and pruritic papules on exposed areas for three years. We were able to induce populovesicular lesions by three consecutive irradiations with 100 J/cm2 UVA and 2 minimal erythematous dose of UVB. However, three weeks after irradiation, a prurigo papule developed at the UVB irradiated site.     

慢性光化性皮炎的DNA流式细胞分析

应用ＤＮＡ流式细胞分析法检测１７例慢性光化性皮炎的皮肤活检标本。１２例（７０．５９％）示异倍体。ＤＮＡ指数（Ｘ±Ｓ）为１．４０±０．８１。增殖指数（Ｘ±Ｓ）为６５．７１±３１．２８。Ｓ和（或）Ｇ２Ｍ期细胞比例亦增加，可能与真皮内浸润的淋巴样细胞有关，但不可认作是恶性的标志。     

Adult-onset actinic prurigo in Thailand

BACKGROUND: Actinic prurigo (AP) is one of the rare idiopathic photodermatosis. It is said to be a familial disease and is usually seen in certain specific geographical areas. The adult-onset type of AP is reported less frequently in the Asian population and has never been reported in Thailand. METHODS: The study population comprised 30 patients. Demographic data were collected. Photo-tests and photo provocation tests for UVA, UVB and visible light were carried out on non-exposed skin. The other investigations included antinuclear antibody, anti-HIV antibody and urine porphyrin level. Histopathology studies were also carried out. RESULTS: There were 18 males and 12 females. The mean age of onset was 36.86 years. The duration of disease was from 1 month to 20 years. Forearms (27 patients) were the most frequently affected site. Other screening tests showed negative results. Five patients had abnormal MED to UVA and one patient had abnormal MED to UVA as well as UVB. Photo provocation tests showed positive responses to both UVA and UVB in 12 cases (40%), a positive response to UVA in 11 cases (37%), a positive response to UVB alone in four cases (13.3%) and a normal response in three patients (10%). None of the patients had a positive response to visible light. Skin biopsies were performed on nodular lesions in 23 cases. Histopathology from these 23 cases showed hyperkeratosis ortho- or parakeratosis and acanthosis in 20 of the 23 cases. CONCLUSIONS: Adult-onset AP in our country may have different geographic and racial distribution from previous reports or may be the tropical variant as described by Tham et al. It may not be an uncommon disease in our country, if there is increased awareness of this disease. Only 16.6% of patients had reduced MED. Photo provocation tests were positive in 90% of cases. Most of the positive wavelengths were UVA or both UVA and UVB. Therefore, photo provocation tests should be performed in cases suspected of AP. The prognosis for AP is not good, despite combinations of treatment. The disorder may run a chronic course. This may be because of our sunny climate and the sun-exposed occupations of patients.     

Tungsten lamp and chronic actinic dermatitis

Chronic actinic dermatitis is often associated with sensitivity to UV light. It is not well recognised that chronic actinic dermatitis may be exacerbated by light in the visible spectrum. We describe an unusual case of chronic actinic dermatitis exacerbated by a tungsten lamp, which emits light in the visible spectrum.     

Erythrodermic chronic actinic dermatitis responding only to topical tacrolimus

Chronic actinic dermatitis (CAD) is a disorder characterized by an often severe persistent eczematous eruption induced by exposure to ultraviolet radiation. Treatment involves photoprotective measures and topical corticosteroid therapy and in more severe cases, systemic immunosuppression. Occasionally, however, the condition can prove very resistant to all therapy and be severely disabling. We report a patient with CAD who resisted standard topical and systemic treatments, but responded to topical tacrolimus ointment 0.1% (Protopic).     

光线性角化病的皮肤镜特征研究进展

光线性角化病（AK）是皮肤长期暴露于日光下所引起的一种癌前病变,有发展为鳞癌的风险,皮肤镜已广泛应用于AK的诊断与鉴别诊断,其皮肤镜特征包括: 基底假网状红斑、毛囊口周围白晕、毛囊口黄色角栓等,本文对AK的皮肤镜表现及鉴别诊断进行了综述。     

Update on actinic keratosis in clinical trial experience with imiquimod

Actinic keratoses (AK) is a sun induced cutaneous lesion, currently considered as a squamous cell carcinoma in situ that has the potential to progress to invasive SCC. To treat them, numerous, ablative and no ablative, therapeutic approaches exist. Among them, imiquimod, a toll like receptor agonist, recently approved to treat them in the US and Europe, has demonstrated to be effective and safe with an acceptable tolerability in the treatment of these lesions. In this article the results of several high quality RCT are analysed.