RESUMO
Actinic prurigo (AP) is a type of photodermatosis that primarily affects the Latin American mestizo population. Histologically, AP cheilitis exhibits acanthosis with spongiosis and vacuolation of the basal cell layer overlying a dense lymphocytic inflammatory infiltrate that forms well-defined lymphoid follicles. Toluidine blue is a thiazide, acidophilic, and metachromatic dye used in vivo to selectively stain the acidic components of tissues such as sulfates, carboxylates, and phosphate radicals that are incorporated into DNA and RNA. It is necessary to develop a method that allows detecting, on clinical grounds the area of the lesion in which it is more feasible to find such structures. Thus to increase the sensitivity of the biopsy, in AP cheilitis to accurately identify where the lymphoid follicles reside, based on the higher concentration of DNA in such structures and thus confirm the diagnosis. In this study, staining was positive in 85% of patients with AP cheilitis, in 14 of whom 82% lymphoid follicles were observed by histopathology. One of the pathologist's problems in establishing the diagnosis of AP is that the main histopathological characteristics are not always identified in the submitted samples because it is not easy to clinically identify the most representative site of the lesion selected for performing a biopsy. Based on our results, we propose using toluidine blue as an auxiliary method to choose a tissue sample to facilitate the diagnosis and allow clinicians to make clinical correlations between the histopathological and therapeutic findings.
Assuntos
Masculino , Feminino , Criança , Adolescente , Adulto , Pessoa de Meia-Idade , Prurigo/diagnóstico , Cloreto de Tolônio , Queilite/diagnóstico , Coloração e Rotulagem/métodos , BiópsiaRESUMO
Actinic prurigo (AP) is an idiopathic photodermatosis; the initial manifestations usually occur during the first decades of life but can appear at any age. Cases are usually diagnosed late once the lesions have exacerbated; due to the extensive involvement of the vermilion border and the etiology, it has been confused with and related to a potentially malignant process. Syndecan-1 and E-cadherin were positive in the epidermis, with moderate-to-intense staining in 100% of samples. Ki67 and MCM3 were expressed in the lower third of the epidermis and showed greater immunolabeling in samples that contained lymphoid follicles (Ki 67: epidermis [17.7% ± 6.79%] and dermis [7.73% ± 6.69%]; MCM3: epidermis [22.92% ± 10.12%] and dermis [6.13% ± 6.27%]). In conclusión AP is a disease in which there is no evidence that the lesions are potentially cancerous. AP cheilitis should not be confused with actinic cheilitis because they are separate entities.
RESUMO
El prurigo actínico es una foto-dermatosis crónica e idiopática, que afecta principalmente a la población de origen mestizo y a la piel foto-expuesta. La enfermedad se distingue por un franco polimorfismo clínico, presentando un 45% de compromiso ocular y entre un 30 a 70% de la semi-mucosa labial. Para su tratamiento se indican: fotoprotección, antihistamínicos, corticoides y talidomida, entre otros. Comunicamos dos pacientes con diagnóstico de prurigo actínico, que realizaron tratamiento con tacrolimus tópico, observándose buena respuesta clínica.
Actinic prurigo is a chronic idiopathic photo dermatosis which is more common in high-altitude living people, mainly in indigenous descendants, affecting skin exposed to light. The disease is characterized by clinical polymorphism, involving 45% ocular manifestations and between 30-70% of labial semi mucous. Treatment is based on: photo protection, antihistamines, corticosteroids, thalidomide, among others. We present two patients diagnosed with actinic prurigo who performed treatment with topical tacrolimus, showing a successful clinical response.
RESUMO
Background: Actinic prurigo (AP) is a chronic, pruritic skin condition caused by an abnormal reaction to sunlight. Aims: The aim of this study is to determine the clinical characteristics of AP in patients attending the National Skin Centre, Singapore, from 1st January 1999 to 30th June 2008. Methods: Cases of AP diagnosed from 1st January 1999 to 30th June 2008 were retrieved from the center’s electronic medical records and analyzed. Results: A total of 11 patients were diagnosed with AP. The mean age at diagnosis was 52 years. There were 9 (82%) Chinese and 2 (18%) Malay patients. Nine (82%) were male and 2 (18%) were female. The most commonly affected areas were the face, forearms, and hands (72%). Phototesting showed reduced minimal erythema dose (MED) to ultraviolet A (UVA) in 5 (46%) patients, both UVA and ultraviolet B (UVB) in 4 (36%) patients and UVB in 1 (9%) patient. Seven (64%) patients reported partial improvement after treatment with a combination of topical corticosteroids and sunscreens. Four (36%) patients received systemic therapy with partial response. Conclusion: Adult-onset AP is more common in the Asian population, with a male predominance. The face, forearms, and hands are the most commonly affected areas. The absence of mucosal involvement is also a distinguishing feature between the Asian and Caucasian population. Close to half of the patients have reduced MED to UVA on phototesting. The prognosis for AP is poor as it tends to run a chronic course with suboptimal response to treatment.