Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0086543 (cataract)
 29,165 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Psoralen photochemotherapy (PUVA) is a combination of orally administered psoralen and long wave ultraviolet-A radiation (UVA), and is one of the most effective forms of therapy for psoriasis. The unwanted effects of PUVA therapy can be divided into short and long term adverse effects. The short term adverse effects include erythema, pruritus, nausea and headache. While short term adverse effects are limited and reversible after discontinuation of treatment, potential long term adverse effects such as chronic actinic skin damage, dyskeratotic and precancerous skin conditions, nonmelanoma skin cancer, immunological alterations and cataract formation are of greater concern. Long term risks associated with PUVA therapy can be minimised by several measures. Careful patient selection is mandatory; for example, patients with chronic actinic damage and a history of skin cancer may bear a higher risk for the development of new cancers, and previous arsenic intake and ionising radiation also increase the risk of nonmelanoma skin cancers. Certain drug combinations make it possible to lower the UVA dose, which is important because of the dose-dependent increase in the incidence of squamous cell carcinomas in patients treated with PUVA. It has been demonstrated that 200 treatments or a total UVA dose of 1200 J/cm2 seems to be the threshold for development of nonmelanoma skin cancer. Shielding male genitalia during PUVA treatment is essential because of the increased risk of genital squamous cell carcinomas. Yearly dermatological examination to detect skin cancer at an early stage is highly advisable. Sunscreen use, protective clothing and avoidance of sun exposure reduce the uncontrolled dose of solar UV radiation. Other psoralens with a less carcinogenic potential can be used. UVA-opaque sunglasses during the entire period of increased photosensitivity after psoralen ingestion help avoid cataract formation. Assignment to PUVA ought to be based on the risk-benefit ratio for the individual patient and should be limited to those who can be monitored and controlled by informed, competent and conscientious physicians.
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PMID:Minimising the risks of PUVA treatment. 850 16

Psoralen compounds such as methoxsalen are photosensitizer agents used in conjunction with ultraviolet A (UVA) radiation exposure as photochemotherapy (Psoralens and ultraviolet-A therapy [PUVA therapy]) for certain epidermal skin disorders such as psoriasis and vitiligo. Methoxsalen has been shown to be associated with premature cataract formation by forming adducts with lens proteins following oral administration and subsequent UVA exposure. Hence, the use of UV-filtering glasses is recommended during PUVA therapy sessions. Ocular tissues can be exposed to its photosensitizing effect with subsequent UV radiation exposure through sunlight if the patient was to be without protective eye glasses, potentially causing macular toxicity. Till date, there have been no reports in the literature of any posterior segment ocular toxicity arising from methoxsalen use. Here, we describe a case of a bilateral macular toxicity in a middle-aged male treated with methoxsalen for vitiligo.
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PMID:Methoxsalen-induced macular toxicity. 2913 67