Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0042109 (urticaria)
 6,569 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

39 patients were treated with carotinoids (beta-carotene alone or combined with canthaxanthine) with an oral dose of 50-150 mg/d, some of them for a period of several years. 23 of these were patients with porphyria (erythropoietic protoporphyria [EPP] 20, congenital erythropoietic porphyria 2, erythropoietic coproporphyria 1); 16 patients were suffering from various photodermatoses (solar urticaria 6, actinic reticuloid 5, UV-A intolerance 1, unclassified photodermatoses 4). Tolerance of the carotinoids was very good; no side effects were seen except for a yellow discoloration of the skin. In 19 of 20 EPP patients the result of the treatment was good, whereas no improvement was seen in the other kinds of porphyria. Of the 16 cases of photodermatoses not caused by porphyrinopathy, 6 responded to the therapy (solar urticaria 2, actinic reticuloid 2, UV-A intolerance 1, unclassified photodermatosis 1). Some cases showed great improvement as a result of the treatment.
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PMID:[Treatment of photodermatoses with carotinoids (author's transl)]. 89 78

We treated with high doses of oral beta carotene (Solatene) (15 to 180 mg/day) 133 patients suffering from erythropoietic protoporphyria (EPP), 27 patients with polymorphous light eruption, six patients with solar urticaria, three patients with hydroa aestivale, one patient with porphyria cutanea tarda, and two patients with actinic reticuloid to relieve the photosensitivity associated with these diseases. Eighty-four percent of the patients with erythropoietic protoporphyria increased by a factor of 3 or more their ability to tolerate sunlight. On the other hand, only nine of the patients with polymorphous light eruption, and one fifth of the patients with all of the other forms of photosensitivity treated showed similar improvement. We conclude that beta carotene is an effective treatment for EPP, but that other forms of photosensitivity will need empirical therapeutic study with beta carotene to determine the range of effectiveness, if any, of this compound in conditions other than EPP.
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PMID:Beta carotene therapy for erythropoietic protoporphyria and other photosensitivity diseases. 90 Sep 68

It is possible in the majority of patients with polymorphic light eruption to produce lesions experimentally. Only the reproduction of the clinical reaction is significant for the diagnosis. Irradiation is carried out in the same test area two or three times with a dose of up to eight times the minimal erythema dose. Sunlight is the best agent for the evaluation of this protocutaneous disorder. A localised area of the skin can be exposed to midday sunshine about half an hour on three consecutive days. But sunlight has the disadvantage of having a variable ultraviolet emission at different times. It is necessary to differentiate lupus erythematosus and photocontact dermatitis, which may produce identical reactions. Other light sources are the hot quartz lamp, fluorescent tube "sun lamp", solar simulator and the monochromater. Patients with polymorphic light eruption are sensitive to light in the range 300 to 320 nm. but some of them are sensitive to savelengths shorter or longer than this range. The methods of protection against solar radiation which have been tried include: 1) Avoidance of sunlight; 2) Promotion of melanin hyperpgimentation and thickening of the stratum corneum-by controlled exposure to sunlight; 3) Application of a film of a chemical compound that will act as a physical screen and absorb, scatter or reflect damaging radiation; 4) Chemical modification of the stratum corneum by topically applied substances which can conjugate chemically or be absorbed onto the stratum corneum and filter the damaging rays. Many authors at present consider the use of alcoholic solutions of para-aminobenzoic acid (PABA) to be the most effective method of preventing reactions from exposure to sunlight. Pathak and Fitzpatrick showed that 5 % PABA in 70 % ethanol and 2,5 % Escalol 506 in 65 % ethanol is the most effective sunscreen against radiation of the sunburn spectrum. A dihydroxyacetone (DHA) and naphthaquinone (lawsone) sunscreen provides photoprotection for all types of photosensitivity throughout the whole UV spectrum even into the visible region. Systemic photoprotection: The administration of beta-carotene to patients with erythropoietic protoporphyria has resulted in amelioriation of their photosensitivity. Antimalarials are valuable therapeutic agents and are highly effective in controlling cutaneous lupus erythematosus, polymorphic light eruption and occasionally solar urticaria.
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PMID:[Polymorphic light dermatitis. Photobiology and photoprotection]. 98 44

Between January 1972 and December 1974, 250 patients were referred for investigation of possible photosensitivity to a university-associated clinical research unit for photobiology. In addition to an appropriate history and clinical examination, phototesting was carried out with a solar simulator, monochromatic light and fluorescent light directed to patch-tested areas of skin. Photosensitivity was not demonstrated in 110 patients (44%). Among the laboratory-confirmed photosensitivities, diagnoses included polymorphous light eruption (4.4%), erythropoietic protoporphyria (3.6%), porphyria cutanea tarda (2%), photoallergic contact dermatitis (5.6%), persistent light reaction (4%), systemic drug phototoxicity (1.2%), phototoxic contact dermatitis (2%), solar urticaria (0.8%) and photoaggravated dermatoses (7.6%). It is important to establish a precise etiologic diagnosis in patients with photosensitivity in order to treat the disorder specifically or effectively or both.
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PMID:Photosensitivity: results of investigation in 250 patients. 120 41

We report on a case of solar urticaria with elevated protoporphyrin in the stool. No other evidence for an erythropoietic protoporphyria could be found.
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PMID:Solar urticaria and disturbed metabolism of porphyrins. 188 58

Photosensitivity to drugs and chemicals in the elderly is more prevalent due to more frequent use of medications. Phototoxic reactions to common, orally administered drugs such as diuretics, cardiac agents and antidiabetics may occur and the reactions may be remedied by discontinuing drug therapy. Photocontact dermatitis due to the ingredients in sunscreens or other agents, such as perfumes, may also arise. Diagnosis is often confirmed by photopatch testing and subsequent avoidance of these agents leads to gradual resolution. Idiopathic photodermatoses, such as sunlight-induced polymorphic light eruption or solar urticaria, may occur and persist from an early age and, in elderly subjects, they can cause mild to marked disability. The most disturbing disorder of this type is the severe, widespread eczematous chronic actinic dermatitis, which can be difficult to diagnose. Porphyrias, such as variegate porphyria or erythropoietic protoporphyria, may persist from an early age, whereas porphyria cutanea tarda generally begins in later life. Porphyrias all have specific clinical and biochemical features and, apart from variegate porphyria, usually respond well to treatment following diagnosis. Exposure of elderly skin to sunlight may also cause deterioration of many ordinary dermatoses, particularly seborrhoeic eczema, which generally respond to protection from UV exposure and to treatment of the underlying abnormality. Progress in identifying the underlying causes, the availability of increasingly sophisticated diagnostic techniques, and improvements in sunscreen preparations and therapeutic medications will probably significantly reduce abnormal photosensitivity in the elderly in the near future.
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PMID:Photosensitivity in the elderly. 218 82

The clinical manifestations, pathophysiology, and treatment of the following common photosensitivity diseases are reviewed in this article: polymorphous light eruption, solar urticaria, drug-induced photodermatoses, chronic actinic dermatitis, porphyria cutanea tarda, and erythropoietic protoporphyria.
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PMID:Photosensitivity disease: pathophysiology and management. 231 26

The porphyrias are the only group of diseases caused by endogenous phototoxic agents. While patients with erythropoietic protoporphyria and those with porphyria cutanea tarda both have skin lesions on sun-exposed areas, there are differences in their cutaneous manifestations. Based on information discussed in this chapter, the following pathophysiologic mechanisms can be proposed. In porphyria cutanea tarda, photoactivation of the complement system in the presence of uroporphyrin results in activation of dermal mast cells, which release their proteases. This results in dermal-epidermal separation, reflected clinically as skin fragility and vesicles. The interaction between activated mast cells with fibroblasts, the nature of which is still unclear, may contribute to fibrosis and sclerodermoid skin changes. The stimulatory effect of uroporphyrin on collagen biosynthesis by fibroblasts, which occurs independent of irradiation, may be responsible for the sclerodermoid lesions seen at sun-exposed as well as sun-protected areas. In erythropoietic protoporphyria, mast cell activation can occur as the result of complement activation induced by protoporphyrin and irradiation. Protoporphyrin and irradiation may also directly induce the release of preformed and generated mediators from mast cells, a process mediated at least in part by peroxidation. The release of mast cell mediators may account for the erythema, edema, and urticaria observed in patients with erythropoietic protoporphyria upon exposure to sunlight. Interaction of mast cells with fibroblasts, and the direct membrane-damaging effect of protoporphyrin and irradiation on the latter, may contribute to the waxy thickening of skin seen in chronically sun-exposed areas of these patients. There are, however, many unanswered questions. What accounts for the different biological effects of mast cell-derived mediators: dermal-epidermal separation in one, erythema and urticaria in the other? The fragmentation of dermal collagen bundles associated with cleavage beneath the lamina densa, and the hyperpigmentation and hypertrichosis observed in some patients with porphyria cutanea tarda remain unexplained. What is the mechanism of the reduplication of blood vessel basal lamina in the non-sun-exposed areas of both types of patient? Are there any roles for cytokines and epidermal cell-derived eicosanoids? While it is clear that the pathogenesis of cutaneous lesions in porphyria cutanea tarda and erythropoietic protoporphyria involves interactions among inflammatory mediators and various cells in skin, much still needs to be done to further our understanding of their pathophysiology.
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PMID:Mechanisms of phototoxicity in porphyria cutanea tarda and erythropoietic protoporphyria. 248 74

The porphyrias can be grouped conveniently by their presenting symptoms. Acute intermittent neurological symptoms of neuritis, abdominal pain and psychoses may occur in acute intermittent porphyria, hereditary coproporphyria and variegata porphyria. Increase of the porphyrin precursors delta-aminolaevulinic acid and porphobilinogen may be observed in the urine during attacks (Watson-Schwartz test). Patients with acute symptoms of photosensitivity with burning pain and oedema within short exposure periods may have erythropoietic protoporphyria, with high erythrocyte and stool protoporphyrins, erythropoietic coproporphyria, and in the last few years of life the more recently described hepatoerythropoietic porphyria. Symptoms of chronic photosensitivity include; hyperpigmentation, hypertrichosis, easy fragility of the skin with bullae and subsequent scarring in porphyria cutanea tarda (PCT), with increased uroporphyrin in the urine and stool; variegate porphyria with increased protoporphyrin and coproporphyrin in the stool; congenital erythropoietic porphyria with an increased copro- and uroporphyrin (isomer I) in the erythrocytes, urine and stool; and hepatoerythropoietic porphyria in later life, in which the chronic features are similar to PCT. In 1913 Meyer-Betz injected himself with 200 mg haematoporphyrin. Initially, at the higher levels, the symptoms were those of solar urticaria as observed in erythropoietic porphyria, but after several months became identical to PCT. A comparison of quantitative porphyrin analysis (performed on 323 patients with porphyria) and chromatography provides additional confirmation for the diagnosis.
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PMID:Porphyria: genetic and acquired. 329 37

At present, three classes of compounds are used as systemic photoprotective agents, but only for specific indications, not for general use in healthy individuals. Beta-carotene prevents or lessens photosensitivity in most patients with erythropoietic protoporphyria and in some patients with other photosensitivity diseases. The antimalarial drugs can clear up skin lesions in patients with polymorphous light eruption and solar urticaria who cannot obtain relief with topical sunscreens and in some patients with porphyria cutanea tarda. Oral psoralens and controlled exposure to sunlight or artificial sources of UVA radiation can increase tolerance to sunlight in fair-skinned individuals and in certain patients with vitiligo or polymorphous light eruption.
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PMID:Systemic photoprotection. 395 2


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