The Porphyrias
نویسنده
چکیده
The porphyrias are a group of disorders of heme metabolism that result from partial defects in the several enzymes that control heme biosynthesis. Accumulation of porphyrins or porphyrin precursors in several different patterns results from these defects and biochemically characterizes each specific syndrome. Patterns of cutaneous photosensitivity and associated systemic symptoms among the several porphyrias result from the types of porphyrins or precursors accumulated in each.
منابع مشابه
Clinically Important Features of Porphyrin and Heme Metabolism and the Porphyrias
Heme, like chlorophyll, is a primordial molecule and is one of the fundamental pigments of life. Disorders of normal heme synthesis may cause human diseases, including certain anemias (X-linked sideroblastic anemias) and porphyrias. Porphyrias are classified as hepatic and erythropoietic porphyrias based on the organ system in which heme precursors (5-aminolevulinic acid (ALA), porphobilinogen ...
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Hereditary porphyrias are a group of eight metabolic disorders of the haem biosynthesis pathway that are characterised by acute neurovisceral symptoms, skin lesions, or both. Every porphyria is caused by abnormal function of a separate enzymatic step, resulting in a specific accumulation of haem precursors. Seven porphyrias are the result of a partial enzyme deficiency, and a gain of function m...
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Porphyrias are a group of metabolic disorders in which there are defects in the normal pathway for the biosynthesis of heme, the critical prosthetic group for numerous hemoproteins. The clinical manifestations of the porphyrias can be highly varied, and patients may present to general physicians and be referred to a wide variety of subspecialists because of these manifestations. However, two ma...
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The inborn errors of heme biosynthesis, the porphyrias, are 8 genetically distinct metabolic disorders that can be classified as "acute hepatic," "hepatic cutaneous," and "erythropoietic cutaneous" diseases. Recent advances in understanding their pathogenesis and molecular genetic heterogeneity have led to improved diagnosis and treatment. These advances include DNA-based diagnoses for all the ...
متن کاملReviewArtiele Gene - EnvironmentalInteractions : Lessons from Porphyria Shigeru SASSA
The porphyrias are uncommon, compSex, and fascinating metabolic conditions, caused by deficiencies in the activities ofthe enzymes ofthe heme biosynthetic pathway. ISvo cardinal symptoms of the porphyrias are cutaneous photosensitivity and neurologic disturbances. Molecular analysis of gene defects has shown that there are multiple and heterogeneous mutations in each porphyria. Patients with sy...
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ورودعنوان ژورنال:
- The Ulster Medical Journal
دوره 50 شماره
صفحات -
تاریخ انتشار 1979