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.     

Treatment of actinic prurigo with PUVA: mechanism of action

Five patients with actinic prurigo were treated twice weekly with PUVA. One area on the back was shielded from UVA throughout the 15-week treatment period. Before PUVA, all patients had increased erythemal sensitivity to UVA and showed abnormal augmentation of UVB erythema by topical indomethacin. After PUVA, all patients were free of photosensitive symptoms and skin that had been exposed to UVA showed normal erythemal responses. By contrast, the areas of skin that had been protected from UVA showed erythemal responses that were unchanged from pre-PUVA values. Augmentation of UVB erythema by topical indomethacin persisted, both on UVA exposed and UVA protected skin. These results show that, although PUVA is an effective treatment in actinic prurigo, it does not alter the underlying mechanism of photosensitivity. The protective effect is local and is due presumably to an increase in melanin pigmentation and epidermal thickness.     

Actinic prurigo, tropical (South-East Asian) variant.

Actinic prurigo is a chronic familial photodermatitis found predominantly among the Amerindians. It has been reported from North and South America, Britain and Japan. We report a case of actinic prurigo seen in Singapore. A 20-year-old Malay female presented with a persistent pruriginous eruption in the sun-exposed parts and on her abdomen. She also had lower lip cheilitis and thinning of the outer eyebrows, features often seen in actinic prurigo. The minimal erythema dose to ultraviolet A (UVA) and UVB were persistently lowered. We propose that this condition be called actinic prurigo, tropical (South-East Asian) variant.     

Aktinische Prurigo

The non-Native American type of actinic prurigo belongs to the group of rare idiopathic photodermatoses and therefore is often diagnosed with delay. The typical clinical and epidemiological features of actinic prurigo are described in a 10 year old girl. Detailed phototesting showed urticarial early onset and prurigo-like late onset reactions towards long-wave UVA. Repetitive photoprovocation with UVB induced delayed development of papules. HLA typing showed the typical association with HLA-DR4, in particular DRB1*0407. Treatment is usually extremely difficult and unrewarding. In this patient, the course was considerably improved by more intense physical photoprotection.     

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.     

沙利度胺联合糠酸莫米松乳膏封包及紫外线照射治疗结节性痒疹的疗效观察

目的 观察沙利度胺联合糠酸莫米松乳膏封包和紫外线照射治疗结节性痒疹的疗效。 方法 采用非随机同期对照研究方法,结节性痒疹患者80例,分别入选对照组（23例）、UVA1组（32例）、UVB组（25例）,3组患者均口服沙利度胺75 mg/d每晚1次,0.1%糠酸莫米松乳膏每晚1次均匀涂抹于整个患侧肢体或躯干部位并用保鲜膜封包;UVA1组和UVB组同时分别给予UVA1和窄谱UVB照射。在治疗前、治疗后30天分别对患者病情严重程度评分。应用秩和检验比较组间皮损临床疗效与瘙痒疗效,同时对外周血嗜酸粒细胞绝对计数与瘙痒视觉评分进行关联性分析。结果 ①治疗30 d后,皮损改善的临床疗效：对照组、UVA1组、UVB组显效分别为5例（21.74%）、13例（43.33%）、9例（37.5%）,有效分别为7例（30.43%）、12例（40%）、7例（29.17%）,对照组疗效显著低于UVA1组（Z = 8.21,P ＜ 0.01）和UVB组（Z = 5.22,P ＜ 0.01）,UVA1组和UVB组疗效接近（Z = 0.50,P ＞ 0.05）;②瘙痒改善的临床疗效：治疗30 d后,对照组、UVA1组、UVB组显效分别为7例（30.43%）、18例（60.00%）、14例（58.33%）,对照组疗效低于UVA1组（Z = 4.50,P ＜ 0.01）和UVB组（Z = 4.50,P ＜ 0.01）,UVA1组与UVB组疗效接近（Z = 0.35,P ＞ 0.05）;③对患者的嗜酸粒细胞计数与瘙痒评分进行相关分析,r = 0.53,P ＜ 0.01。结论 沙利度胺联合糠酸莫米松乳膏封包,及联合紫外线照射治疗结节性痒疹均有显著疗效,且联合UVA1、UVB的疗效优于沙利度胺联合糠酸莫米松乳膏封包。     

Mechanisms of phototherapy and photochemotherapy for photodermatoses

Most photodermatoses represent indications for preventive ultraviolet (UV) phototherapy and/or psoralen plus ultraviolet A (PUVA) photochemotherapy. The aim of treatment is to prevent the outbreak of disease by increasing the patient's tolerance to sunlight. The mechanisms by which ultraviolet B (UVB) and PUVA induce such tolerance are not completely understood. Pigmentation and skin thickening may be important factors in the protective effect, but they cannot sufficiently explain the degree of protection induced. Other mechanisms that may be of critical importance for the therapeutic efficacy encompass a variety of immunomodulatory effects on human skin known to be induced by UVA, UVB, and PUVA. Obviously the mechanisms of prophylactic phototherapy are strongly intertwined with the pathogenesis of the photodermatoses. The possible mechanisms of photoprevention are discussed for polymorphic light eruption (PMLE), actinic prurigo, chronic actinic dermatitis, and solar urticaria.     

Phototesting in Oriental patients with lupus erythematosus

Light sensitivity is an important clinical characteristic of several forms of lupus erythematosus (LE). Recently, investigations have been able to induce LE-like lesions in LE patients with UVA as well as UVB, although most of these studies were conducted in Caucasians. Thus, there is insufficient data on phototesting in Oriental patients with LE. The aim of this study was to evaluate light sensitivity in Oriental patients with LE. Fifteen patients with various forms of LE were tested. Patients were evaluated by provocative phototesting, and threshold doses of UVA and UVB radiation that produced erythema and pigmentation were determined. The minimal erythema doses (MED) of UVB, immediate pigment darkening (IPD), and minimal tanning doses (MTD) were within the normal range in LE patients compared to a control group. Skin lesions clinically and histologically compatible with LE were induced in two of six patients with SLE, and four of nine patients with DLE. These lesions developed in about 2 weeks (range 5 to 23 days) after irradiation and lasted approximately 1 to 3 months (47±24 days). The action spectrum of the induced lesions was within the UVB range in four patients, in the UVA range in one patient, and in the UVB and UVA ranges in one patient. We found no correlation between a positive history for UV sensitivity and phototest reactions. In conclusion, the incidence of positive phototest reactions in Oriental patients with LE seems to be similar to or a little lower than in Caucasians. There was no correlation between a positive history for UV sensitivity and phototest reactions.     

Chronic actinic dermatitis: A clinical study of 15 cases in northern Taiwan

BackgroundChronic actinic dermatitis (CAD) is an idiopathic photosensitive dermatosis induced by ultraviolet B (UVB), sometimes ultraviolet A (UVA), and occasionally visible light. Diagnosis is suggested by the clinical findings, typically a chronic eczematous rash on the sun exposed areas, and confirmed by phototesting, which demonstrates the abnormal photosensitivity. The aim of this study was to determine the characteristics of CAD in Taiwanese patients.MethodsWe retrospectively reviewed the clinical and photobiological features of all patients diagnosed as having CAD at our institute from 2002 to 2012.ResultsA total of 15 patients with CAD were identified. The mean age at diagnosis was 58.6 years (range, 28–82 years). All the patients were males. The face, neck, forearms, and dorsal hands were most commonly involved. Eight patients (53.3%) had decreased minimal erythema dose (MED) to both UVB and UVA; six patients (40.0%) had decreased MED to only UVB; one patient (6.7%) had decreased MED to only UVA. All were managed with photoprotection and topical corticosteroids. Four patients received azathioprine (50 mg twice a day to every other day) and one received prednisolone (10 mg per day to every other day).ConclusionIn Taiwan, CAD affects elderly men more commonly. The most common phototest results were decreased MED to both UVB and UVA, followed by to UVB alone. All patients were managed with photoprotection and topical corticosteroids, and some also required systemic agents, in particular azathioprine.     

Successful thalidomide therapy for actinic prurigo in a European woman

Actinic prurigo is a rare, often difficult‐to‐treat, idiopathic photodermatosis. Actinic prurigo is divided into a hereditary form appearing in the Native American population and a sporadic form occurring in non‐Native Americans. We present a 28‐year‐old Caucasian woman who developed typical clinical signs and symptoms of actinic prurigo, just as had her mother and grandmother. The patient and her mother were HLA‐A24 and HLA‐DR 4 with the subtype HLA‐DRB1*0408. Based on clinical symptoms and the HLA pattern, the diagnosis of actinic prurigo was made. Treatment with thalidomide led to resolution of the disease. This case report of a Caucasian woman suffering from a hereditary form of actinic prurigo questions the established classification of actinic prurigo into a hereditary Native American form and a sporadic form occurring in the non‐Native American population.     

Disseminated superficial actinic porokeratosis: Experimental induction and exacerbation of skin lesions

A 55-year-old woman with disseminated superficial actinic porokeratosis (DSAP) had lesions on sun-exposed skin areas that were exacerbated during the summer months and involuted in winter. This is the third report in which induction and exacerbation of DSAP lesions were achieved by irradiation with artificial ultraviolet light sources. Our data show that UVB plus UVA is more effective in inducing new or exacerbating preexisting skin lesions than either wavelength alone. We believe that testing with the appropriate ultraviolet light sources is a practical means to differentiate between DSAP and disseminated superficial porokeratosis.     

Failure of physiologic doses of pure UVA or UVB to induce lesions in photosensitive cutaneous lupus erythematosus: implications for phototesting

BACKGROUND: Phototesting studies in cutaneous lupus erythematosus have yielded variable results, with most trials reporting photo-induction of lesions by both UVA and UVB in substantial numbers of patients. OBJECTIVES: To determine the minimal erythema dose in patients with subacute cutaneous lupus erythematosus (SCLE) and controls. PATIENTS/METHODS: We phototested nine patients with SCLE and 14 skin type-matched controls, using repetitive dosing of UVA1 and UVB, but with filters that removed most of the shorter UVC and longer infrared and visible light. In addition, DNA was isolated from anticoagulated blood to genotype the TNF-alpha 308 region in each patient and control. RESULTS: We were unable to demonstrate a difference in minimal erythema dose (MED) between patients and controls, or any correlation of MED with either TNF genotype or systemic drug therapy for SCLE. In addition, no SCLE skin lesions were induced in the nine patients with either UVA or UVB, and one patient cleared a skin lesion after low-dose UVA1 irradiation. CONCLUSIONS: The potential role of wavelengths outside the UVA and UVB range in the photo-induction of cutaneous lupus skin lesions needs to be investigated, and there is a need to standardize phototesting equipment and procedures for patients with cutaneous lupus erythematous.     

Case for diagnosis. Actinic prurigo

A 13-year-old black boy had pruritic papular and nodular lesions on his forearms associated to edema of the lower lip, photophobia, conjunctivitis and pterygium. Skin biopsy of the lower lip revealed acanthosis, spongiosis with dermal perivascular mononuclear cell infiltration composed by lymphocytes, plasma cells and eosinophils consistent with actinic prurigo. Lesions improved considerably with the use of thalidomide 100mg/ day.     

Chronic actinic dermatitis developed during phototherapy for psoriasis

A patient with psoriasis vulgaris had been successfully treated with PUVA and UVB therapy. During maintenance phototherapy, he suddenly became photosensitive and developed eczematous eruption. Minimal response doses to UVB and UVA were extremely low--1.09 mJ/cm2 and 0.3 J/cm2, respectively. No chemical substances were identified as the responsible photosensitizer. The condition was diagnosed as chronic actinic dermatitis (CAD). PUVA therapy was unsatisfactory because it was not possible to administer an adequate dose of UVA. Oral cyclosporine, topical corticosteroid and sunscreen were used with beneficial therapeutic effects on psoriasis and CAD. As far as we know, the development of CAD during phototherapy has not been previously reported.     

Lymphocyte subtypes and adhesion molecules in actinic prurigo: observations with cyclosporin A

BACKGROUND: Actinic prurigo is a photodermatitis in which UV light is implicated by an unknown mechanism. METHODS: Skin biopsies of 19 patients with actinic prurigo and 11 controls were analyzed by immunohistochemistry. RESULTS: In actinic prurigo patients, there was a significant increase in the number of CD3, CD4, CD8, CD45RA, CD45RO, and CD45RB lymphocytes and Langerhans cells, as well as in the level of human leukocyte antigen-DR (HLA-DR) expression and cell adhesion molecules lymphocyte functional antigen-1 (LFA-1), intercellular adhesion molecule-1 (ICAM-1), and endothelial leukocyte adhesion molecule-1 (ELAM-1). Actinic prurigo patients were treated with cyclosporin A (CsA), and a final skin biopsy was taken after 6 months of treatment. All the cell populations and markers studied, except for the CD4 lymphocytes, Langerhans cells, and HLA-DR expression, returned to normal levels. CONCLUSIONS: CsA was found to be effective in relieving the clinical symptoms of actinic prurigo.     

Effects of UV radiation on the ultrastructure of human common pigmented naevi and lentigines.

In order to investigate how sunlight may affect naevi and lentigines, their melanocytes and the basement membrane, three irradiation protocols were applied directly to ten naevi and five lentigines on 2 subjects. Neither volunteer had sufficient naevi and lentigines to be able to use the three irradiation protocols on each of the subjects. Skin biopsies were fixed in glutaraldehyde followed by osmium tetroxide, thin-sectioned and examined in a Hitachi H-7000 transmission electron microscope. Following 14 consecutive single exposures of 3 MED of UVB or single exposures followed by 25 J/cm2 of UVA, 350 J/cm2 UVA with either 2040 or 2280 mJ/cm2 UVB, the basement membrane maintained its continuity. Melanocytes were not observed on the dermal side of the epidermal-dermal junction. UVA irradiation stimulated reinforcement of the basement membrane zone by collagen fibers. Centrioles found in melanocytes following irradiation suggest that these melanocytes maybe undergoing mitosis. Dermal fibroblasts were found to contain comparatively large quantities of melanin pigment. The pigment contained in these fibroblasts may in fact constitute an additional barrier against UV irradiation.     

Actinic prurigo: a case report with successful induction of skin lesions

A 7-year-old girl with actinic prurigo, probably the first ever published case in Japan, is reported. Intensive irradiation of UV-B and light application of carbon dioxide snow induced the characteristic papules indicating that the patient seemed to respond to various kinds of external stimuli. However, pruritus did not always accompany the appearance of these induced skin lesions. The presentation of skin lesions of actinic prurigo on covered skin and in the winter may partly be explained by these observations.     

紫外线照射后生成的微囊泡对成纤维细胞氧化损伤及凋亡的作用

目的：明确对UVA及UVB照射后皮肤成纤维细胞生成的微囊泡对成纤维细胞氧化损伤及凋亡的作用。方法：紫外线照射人皮肤成纤维细胞,提取细胞上清液中的微囊泡,利用光散射分析技术鉴定分析微囊泡的大小及数量。将紫外线照射后生成的微囊泡与正常成纤维细胞共孵育,荧光酶标仪定量检测活性氧含量,流式细胞仪检测细胞凋亡率。结果：UVA及UVB照射后皮肤成纤维细胞释放的微囊泡数量及大小明显高于正常成纤维细胞释放的微囊泡。正常纤维细胞、UVA和UVB照射后的成纤维细胞与微囊泡共孵育后活性氧荧光值分别为（52.76±1.4347）、（82.60±4.082）和（85.94±6.264）,凋亡率分别为（3.260±1.732）%,（28.94±2.430）%和（34.48±2.718）%,细胞的氧化损伤和凋亡可被抗氧化剂逆转。结论：急性中长波紫外线照射可诱导皮肤成纤维细胞释放微囊泡进一步介导细胞的氧化损伤和凋亡。