Pathogenesis[ edit ] Heme synthesis—note that some reactions occur in the cytoplasm and some in the mitochondrion yellow In humansporphyrins are the main precursors of hemean essential constituent of hemoglobinmyoglobincatalaseperoxidaseand P liver cytochromes.
General Discussion Summary Hepatoerythropoietic porphyria HEP is an extremely rare genetic disorder characterized by deficiency of the enzyme, uroporphyrinogen decarboxylase.
Most affected individuals have a profound deficiency of this enzyme and onset of the disorder is usually during infancy or early childhood. However, some individuals may have a mild form that can go undiagnosed until adulthood. The childhood form of HEP is often associated with painful, blistering skin lesions that develop on sun-exposed skin photosensitivity.
Affected areas of skin can scar and become discolored. There may Essays on hepatoerythropoietic porphyria risk of bacterial infection. Abnormal, excessive hair hypertrichosis on affected skin is also common.
Mild cases of HEP may go unrecognized until adulthood and can be clinically indistinguishable from porphyria cutanea tarda PCTa related disorder that may be acquired or occur in individuals with a mutation of one UROD gene autosomal dominant inheritance.
NORD has a separate report on porphyria cutanea tarda. Introduction HEP belongs to a group of disorders known as the porphyrias. This group of at least seven disorders is characterized by abnormally high levels of porphyrins and porphyrin precursors due to deficiency of certain enzymes essential to the creation synthesis of heme, a part of hemoglobin and other hemoproteins.
There are eight enzymes in the pathway for making heme and at least seven major forms of porphyria. The symptoms associated with the various forms of porphyria differ.
It is important to note that people who have one type of porphyria do not develop any of the other types. Porphyrias are generally classified into two groups: Porphyrins and porphyrin precursors and related substances originate in excess amounts predominantly from the liver in the hepatic types and mostly from the bone marrow in the erythropoietic types.
Porphyrias with skin manifestations are sometimes referred to as "cutaneous porphyrias". The term "acute porphyria" is used to describe porphyrias that can be associated with sudden attacks of pain and other neurological symptoms.
HEP is a hepatic and cutaneous porphyria. Onset is usually within the first two years of life, but mild cases that go undiagnosed until adulthood have been reported.
Although HEP is associated with specific, characteristic symptoms, several factors, including the small number of identified cases, make it difficult to establish the full range of associated symptoms of the disorder.
Severe cutaneous photosensitivity is usually the first sign. Affected infants may have extremely fragile skin that that can peel or blister on minimal impact is common. Reddening of the skin is common erythema. Blistering skin lesions can develop on sun-exposed skin such as the hands and face.
Photosensitivity can be severe and can cause scarring, erosion, and disfigurement. Bacterial infection of skin lesions can occur.
Abnormal, excessive hair growth hypertrichosis may also occur on sun-exposed skin. Affected skin may darken or lose color hyper- or hypopigmentation.
Small bumps with a distinct white head milia may also develop.
Some affected individuals have teeth that are reddish-brown colored erythrodontia. Low levels of circulating red blood cells anemia may also occur. Anemia may be due to the premature destruction of red blood cells hemolysis.
Anemia associated with HEP may be mild or severe.We will write a custom essay sample on Porphyria specifically for you.
for only $/page. Cutaneous porphyrias include congenital erythropoietic porphyria, erythropoietic protoporphyria, hepatoerythropoietic porphyria, and porphyria cutanea tarda. Other types of porphyria, called acute porphyrias, primarily affect the nervous system.
Search the history of over billion web pages on the Internet. Hepatoerythropoietic Porphyria (HEP) is a very rare form of hepatic porphyria that manifests as a skin condition. In this condition, the skin is severely sensitive to light, which often presents as blistering, scarring, and severe disfigurement.
Porphyria cutanea tarda (PCT; previously called symptomatic porphyria, chemical porphyria, toxic porphyria) is the most common of the porphyrias.
PCT was named by Waldenström in to emphasize the predominant cutaneous manifestations and relatively late onset of disease [ 1 ]. essays on hepatoerythropoietic porphyria write me an essay, cheap research paper ghostwriter for hire for universitylogic editing websitesexplain the difference between comparative and absolute advantage essayfree persuasive essays on recyclingesl thesis proposal writers sites online?
how to write thematic essay for global regents, articles. The hepatoerythropoietic porphyria is a very severe, autosomal recessive form of porphyria that develops in infancy and is characterized by excretion of acetate-substituted porphyrins and accumulation of protoporphyrin in erythrocytes1,3,5.