RESUMO
Drug-induced photosensitivity occurs when a drug is capable of absorbing radiation from the sun (usually ultraviolet A) leading to chemical reactions that cause cellular damage (phototoxicity) or, more rarely, form photoallergens (photoallergy). The manifestation varies considerably in presentation and severity from mild pain to severe blistering. Despite screening strategies and guidelines in place to predict photoreactive drugs during development there are still new drugs coming onto the market that cause photosensitivity. Thus, there is a continuing need for dermatologists to be aware of the different forms of presentation and the culprit drugs. Management usually involves photoprotection and cessation of drug treatment. However, there are always cases where the culprit drug is indispensable. The reason why some patients are susceptible while others remain asymptomatic is not known. A potential mechanism for the phototoxic reactions is the generation of reactive oxygen species (ROS), and there are a number of reasons why some patients might be less able to cope with enhanced levels of ROS.
Assuntos
Transtornos de Fotossensibilidade/induzido quimicamente , Apoptose/efeitos dos fármacos , Dermatite Fotoalérgica/etiologia , Dermatite Fototóxica/etiologia , Diagnóstico Precoce , Humanos , Hiperpigmentação/induzido quimicamente , Queratinócitos/fisiologia , Dor/induzido quimicamente , Pelagra/induzido quimicamente , Transtornos de Fotossensibilidade/diagnóstico , Transtornos de Fotossensibilidade/terapia , Porfirias/induzido quimicamente , Espécies Reativas de Oxigênio/farmacologia , Pigmentação da Pele/efeitos dos fármacos , Queimadura Solar/etiologiaRESUMO
Critically appraised topics (CATs) are essential tools for busy clinicians who wish to ensure that their daily clinical practice is underpinned by evidence-based medicine. CATs are short summaries of the most up-to-date, high-quality available evidence that is found using thorough structured methods. They can be used to answer specific, patient-orientated questions that arise recurrently in real-life practice. This article provides readers with a detailed guide to performing their own CATs. It is split into four main sections reflecting the four main steps involved in performing a CAT: formulation of a focused question, a search for the most relevant and highest-quality evidence, critical appraisal of the evidence and application of the results back to the patient scenario. As well as helping to improve patient care on an individual basis by answering specific clinical questions that arise, CATs can help spread and share knowledge with colleagues on an international level through publication in the evidence-based dermatology section of the British Journal of Dermatology.
Assuntos
Medicina Baseada em Evidências , Projetos de Pesquisa , Redação , Medicina Clínica , Humanos , Armazenamento e Recuperação da InformaçãoRESUMO
BACKGROUND: Published methodology used to determine psoralen plus ultraviolet A (PUVA) erythemal action spectrum does not reflect current clinical practice for psoralen sensitization. We re-evaluated the PUVA action spectrum using aqueous 8-methoxypsoralen (8-MOP) 2·6 mg L(-1) as used routinely in current clinical practice. OBJECTIVES: To determine the UVA erythema action spectrum of topical 8-MOP-sensitized normal skin. METHODS: Twenty healthy volunteers with skin phototypes I-V were recruited. Forearms were psoralen-sensitized at 37 °C for 10 min. Six UVA irradiations at 10-nm intervals between 325 and 375 nm were randomly allocated to forearm sites and were applied using a 10-nm bandwidth irradiation monochromator. The visual minimal phototoxic dose (MPD) was recorded on each site at 96 h. RESULTS: Volunteer Boston phototypes were: I, n = 2; II, n = 6; III, n = 6; IV, n = 5 and V, n = 1. The mean MPD (J cm(-2) ) for all subjects at each wavelength was as follows: 325 nm, 0·64 (SD 0·37); 335 nm, 0·80 (SD 0·58); 345 nm, 0·96 (SD 0·55); 355 nm, 1·50 (SD 0·85); 365 nm, 2·19 (SD 0·90); and 375 nm, 2·89 (SD 1·06). Therefore, the relative sensitization at each wavelength (erythemal action spectrum) was: 1, 0·83, 0·67, 0·43, 0·29 and 0·22. There were significant differences between the PUVA erythemal effectiveness at different wavelengths but none between skin types. CONCLUSIONS: This study has established the erythemal action spectrum for bath/soak PUVA therapy as is currently performed. In all volunteers, the peak sensitivity was at 325 nm. All volunteers showed a similar trend across the wavelengths studied irrespective of skin type. The determination of the action spectrum for PUVA-induced erythema is important as it permits reliable estimates of erythemal efficacy of any UVA source where the emission spectrum of the lamp is known or can be measured.
Assuntos
Eritema/induzido quimicamente , Metoxaleno/efeitos adversos , Terapia PUVA/efeitos adversos , Fármacos Fotossensibilizantes/efeitos adversos , Espectro de Ação , Adulto , Idoso , Análise de Variância , Dermatite Fototóxica/etiologia , Relação Dose-Resposta à Radiação , Feminino , Antebraço , Voluntários Saudáveis , Humanos , Masculino , Metoxaleno/administração & dosagem , Pessoa de Meia-Idade , Fármacos Fotossensibilizantes/administração & dosagem , Adulto JovemRESUMO
Targeted ultraviolet B (UVB) phototherapy is defined as UVB radiation applied only to clinically diseased skin, with sparing of adjacent normal skin, unlike conventional phototherapy, which involves irradiation of both diseased and normal skin. Targeted UVB radiation is a relatively new concept, which is now widely available because of advances in technology. Devices developed for targeted UVB phototherapy of the skin include the monochromatic excimer laser and lamp, both of which are now used by dermatologists in developed and developing countries. The aim of this review is to collate data from research studies on targeted phototherapy and to provide a concise description of currently available devices, their clinical indications and therapeutic efficacy. Additionally, potential adverse effects are summarized, and the limitations of these novel devices are highlighted.
Assuntos
Dermatopatias/terapia , Terapia Ultravioleta/métodos , Terapia Combinada , Humanos , Terapia Ultravioleta/efeitos adversosRESUMO
A 2006 survey of dermatologists showed that home phototherapy should be used with caution, and that general, nonevidence-based opinions were widespread about this form of therapy. This led to a randomized controlled trial to assess the safety and efficacy of home phototherapy vs. outpatient phototherapy by the same authors in 2009, which concluded that a lower burden of treatment and increased patient satisfaction were associated with home phototherapy. In the UK National Health Service, with a single exception, phototherapy is currently carried out exclusively in hospital. This contrasts with the Netherlands, where home phototherapy is now widely available. NHS dermatology services in the UK have yet to adopt home phototherapy as a treatment option, despite the strong evidence base and robust service models established elsewhere. In this review, we discuss evidence-based papers on home phototherapy, its advantages and disadvantages, economic effectiveness, and a suggested model for service sustainability.
Assuntos
Serviços de Assistência Domiciliar , Fototerapia/métodos , Psoríase/terapia , Análise Custo-Benefício , Humanos , Satisfação do Paciente , Reino UnidoAssuntos
Dermatologia/organização & administração , Medicina Baseada em Evidências/organização & administração , Necessidades e Demandas de Serviços de Saúde , Hospitalização , Dermatopatias/terapia , Dermatologia/métodos , Medicina Baseada em Evidências/métodos , Humanos , Preferência do Paciente , Reino UnidoRESUMO
We present two cases of a rare clinical condition presenting as a delayed and transient pruritus of the trunk following sun exposure. These cases differ from previously reported conditions such as brachioradial pruritus because of the transient nature and anatomical location of the itching. These two cases extend the clinical spectrum of sun-induced pruritus. The patients' initial response to rigorous sun protection is good, but the specific treatment and natural history of the condition have yet to be determined.
Assuntos
Prurido/etiologia , Luz Solar/efeitos adversos , Adulto , Idoso , Humanos , Masculino , Tronco , Raios Ultravioleta/efeitos adversosRESUMO
X-linked dominant protoporphyria (XLDPP) was first reported in the genetics literature in 2008. It has a phenotype very similar to erythropoietic protoporphyria (EPP), but is distinguished from EPP by higher concentrations of erythrocyte protoporphyrin (of which a high proportion is zinc-chelated), its apparently higher incidence of liver disease, and an X-linked dominant pattern of inheritance. Dermatologists should understand how XLDPP differs from EPP, in order to advise newly diagnosed patients correctly about the genetic implications and the long-term management strategy. We present a case series of XLDPP to introduce this condition to the dermatology literature.
Assuntos
5-Aminolevulinato Sintetase/deficiência , Doenças Genéticas Ligadas ao Cromossomo X/diagnóstico , Protoporfiria Eritropoética/diagnóstico , 5-Aminolevulinato Sintetase/genética , Adolescente , Feminino , Humanos , Mutação , Linhagem , Protoporfirinas/sangueRESUMO
BACKGROUND: The traditional method of assessing minimal phototoxic dose (MPD) prior to photochemotherapy with psoralen-ultraviolet A (PUVA) is inconvenient and cannot directly determine PUVA start doses. A handheld minimal erythema dose UVB tester can be modified by fitting a TL-10 UVA compact fluorescence lamp (CFL). OBJECTIVES: To determine whether MPD testing is possible with a CFL and to calculate a fixed factor to convert observed MPD to PUVA-equivalent MPD. METHODS: Patients had two sets of MPD tests performed on symmetrical, contralateral sites on the lower back. MPD test results from a panel of PUVA lamps were compared with MPD from the modified handheld tester. Additionally, a questionnaire survey was completed by 43 U.K. phototherapy units to assess routine practice concerning MPD testing prior to PUVA therapy. RESULTS: Thirty-seven patients with psoriasis were recruited. Boston phototypes in the 31 with conclusive MPD reactions were: I, four; II, 11; III, 12; and IV, four. The handheld MPD results were linearly related to the PUVA panel MPD results as follows: PUVA MPD = 0·48 × handheld MPD + 0·17 J cm(-2). The measured PUVA MPD was 0·48 of the handheld MPD, not 0·15 as predicted by the published PUVA action spectrum. CONCLUSIONS: The modified MPD tester is a convenient and safe method for PUVA MPD testing, overcoming many problems of the 'traditional method'. The difference between the PUVA and TL-10 lamps was lower than predicted from published studies. This suggests that formal re-evaluation of the erythema action spectrum for PUVA is now needed.
Assuntos
Terapia PUVA/instrumentação , Psoríase/tratamento farmacológico , Adolescente , Adulto , Idoso , Feminino , Humanos , Masculino , Metoxaleno/administração & dosagem , Pessoa de Meia-Idade , Terapia PUVA/métodos , Fármacos Fotossensibilizantes/administração & dosagem , Estudos Prospectivos , Doses de Radiação , Adulto JovemRESUMO
Photosensitivity to UVB is a prominent feature of a small number of congenital skin disorders. In addition UVB may also contribute to the action spectrum of a number of acquired photosensitivity syndromes. The gene mutations underlying the genetically inherited disorders have largely been identified and have provided insights into DNA repair pathways. The pathomechanisms for the acquired disorders are still largely undefined. Few therapeutic options are available so management of all these disorders still relies on rigorous photo-protection.
Assuntos
Transtornos de Fotossensibilidade/genética , Raios Ultravioleta , Reparo do DNA/genética , Humanos , Hipersensibilidade/metabolismo , Hipersensibilidade/patologia , Sistema Imunitário/metabolismo , Sistema Imunitário/efeitos da radiação , Mutação , Transtornos de Fotossensibilidade/metabolismo , Transtornos de Fotossensibilidade/patologiaAssuntos
Dermatite Esfoliativa/tratamento farmacológico , Exantema/tratamento farmacológico , Pitiríase Rubra Pilar/tratamento farmacológico , Ustekinumab/uso terapêutico , Idoso , Anticorpos Monoclonais/uso terapêutico , Medicina Comunitária/métodos , Dermatite Esfoliativa/patologia , Fármacos Dermatológicos/administração & dosagem , Fármacos Dermatológicos/farmacologia , Fármacos Dermatológicos/uso terapêutico , Exantema/patologia , Feminino , Visita Domiciliar , Humanos , Pitiríase Rubra Pilar/patologia , Resultado do Tratamento , Ustekinumab/administração & dosagem , Ustekinumab/farmacologiaAssuntos
Dermatologistas/estatística & dados numéricos , Clínicos Gerais/estatística & dados numéricos , Serviços de Assistência Domiciliar/estatística & dados numéricos , Fototerapia/estatística & dados numéricos , Humanos , Programas Nacionais de Saúde , Padrões de Prática Médica/estatística & dados numéricos , Inquéritos e Questionários , Reino UnidoAssuntos
Serviços de Assistência Domiciliar/organização & administração , Fototerapia/métodos , Psoríase/terapia , Simulação por Computador , Efeitos Psicossociais da Doença , Custos e Análise de Custo , Serviços de Assistência Domiciliar/economia , Hospitalização/economia , Hospitalização/estatística & dados numéricos , Humanos , Planejamento de Assistência ao Paciente/economia , Planejamento de Assistência ao Paciente/organização & administração , Fototerapia/economia , Psoríase/economia , Saúde da População Rural , Viagem/economia , Viagem/estatística & dados numéricos , País de GalesRESUMO
BACKGROUND: Congenital erythropoietic porphyria (CEP) is an autosomal recessive photomutilating porphyria with onset usually in childhood, where haematological complications determine prognosis. Due to its extreme rarity and clinical heterogeneity, management decisions in CEP are often difficult. OBJECTIVES: To develop a management algorithm for patients with CEP based on data from carefully characterized historical cases. METHODS: A single investigator collated data related to treatments and their outcomes in 29 patients with CEP from the U.K., France, Germany and Switzerland. RESULTS: Six children were treated with bone marrow transplantation (BMT); five have remained symptomatically cured up to 11.5 years post-transplantation. Treatments such as oral charcoal, splenectomy and chronic hypertransfusion were either of no benefit or were associated with complications and negative impact on health-related quality of life. Lack of consistent genotype-phenotype correlation meant that this could not be used to predict disease prognosis. The main poor prognostic factors were early age of disease onset and severity of haematological manifestations. CONCLUSIONS: A management algorithm is proposed where every patient, irrespective of disease severity at presentation, should receive a comprehensive, multidisciplinary clinical assessment and should then be reviewed at intervals based on their predicted prognosis, and the rate of onset of complications. A BMT should be considered in those with progressive, symptomatic haemolytic anaemia and/or thrombocytopenia. Uroporphyrinogen III synthase genotypes associated with poor prognosis would additionally justify consideration for a BMT. Rigorous photoprotection of the skin and eyes from visible light is essential in all patients.