Vp has also been called porphyria variegata, south african genetic porphyria, mixed porphyria an obsolete term also applied to hereditary coproporphyria hcp, protocoproporphyria, and porphyria cutanea tarda hereditaria which likely included some cases. These attacks are infrequent because penetrance is low and they are difficult to diagnose because they are nonspecific. Variegate porphyria omim 176200, like hereditary coproporphyria, may be associated with acute episodes as seen in acute intermittent porphyria and with photocutaneous. The acute porphyrias also referred to as acute hepatic porphyrias, which include acute intermittent porphyria aip, hereditary coproporphyria hcp, and variegate porphyria vp, are. Variegate porphyria nord national organization for rare. In 1963 a world conference on the porphyrias was held at cape town under the chairmanship of professor w. The autosomal dominant acute hepatic porphyrias, acute intermittent porphyria aip, variegate porphyria vp and hereditary coproporphyria hcp, are rarely present before puberty. Acute porphyria biomarkers for disease activity the safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Variegate porphyria definition of variegate porphyria by. It is an inherited disorder characterised by skin photosensitivity reaction to light, systemic symptoms arising from neurological. The rare homozygous variant of vp is characterized by severe ppox deficiency, onset of photosensitization by porphyrins in early childhood, skeletal abnormalities of the hand, and, less constantly, short stature, mental retardation, and convulsions roberts et al. Variegate porphyria is a rare genetic metabolic disorder characterized by deficient function of the enzyme protoporphyrinogen oxidase ppo or ppox. Conventionally, variegate porphyria is most readily diagnosed by measurement of fecal porphyrin concentrations.
Treatment for symptoms depends on the type of porphyria you have. Porphyria is usually inherited one or both parents pass along an abnormal gene to their child. Do you or anyone in your family suffer from porphyria, please join and assist us to gain more knowledge about these conditions in the interest of dealing more effectively with them. Variegate porphyria vp is a cutaneous porphyria with chronic blistering skin lesions and an acute porphyria with severe episodic neurovisceral symptoms. Throughout the world, over 100 mutations have been shown to result in defective protoporphyrinogen oxidase activity and variegate porphyria. The vampires disease or porphyria which is its scientific term is a set of genetic disorders in which an important part of hemoglobin called heme is not made. Identification of asymptomatic children who have inherited these disorders is an important aspect of the management of the disease in their families and. These prevalence extrapolations for variegate porphyria are only estimates, based on applying the prevalence rates from the us or a similar country to the population of other countries, and therefore may have very limited relevance to the actual prevalence of variegate porphyria in any region. The genetic defect in the ppox gene leads to a partial defect of protoporphyrinogen oxidase, the penultimate enzyme.
Doctors and medical specialists for variegate porphyria. In most patients, clinical expression requires co inheritance of a low expression allele that is present in about 10% of the general population. Epp is an autosomal dominant disorder with low penetrance. Fecal porphyrin analysis can differentiate vp, acute intermittent porphyria aip, and hereditary coproporphyria hcp, the only diseases that. These prevalence extrapolations for variegate porphyria are only estimates, based on applying the prevalence rates from the us or a similar country to the population of other countries, and therefore. Variegate porphyria arises from autosomal dominant inheritance of a gene mutation encoding a defective protoporphyrinogen oxidase enzyme.
A read is counted each time someone views a publication summary such as the title, abstract, and list of authors, clicks on a figure, or views or downloads the fulltext. There is an interesting history attached to vp in south africa. Variegate porphyria an overview sciencedirect topics. Pregnancy and delivery porphyria for professionals.
Variegate porphyria vp is an autosomal dominant disorder that is a member of a family of disorders referred to as the porphyrias. Variegate porphyria, also known by several other names, is an autosomal dominant porphyria. Apr 15, 2020 the acute porphyrias also referred to as acute hepatic porphyrias, which include acute intermittent porphyria aip, hereditary coproporphyria hcp, and variegate porphyria vp, are characterized by neurovisceral attacks that can cause neurologic damage and death if not treated promptly. William was indeed confirmed clinically by three different independent.
Children of a gene carrier for an autosomal dominant form of acute porphyria acute intermittent porphyria, hereditary coproporphyria, variegate porphyria have a 50% risk of inheriting the disorder. Haem is the red pigment in blood cells and is an important component of haemoglobin, the molecule that carries oxygen in the blood. The most common type of porphyria is porphyria cutanea tarda. One mutation, the r59w mutation, represents the founder mutation in the south african population, and accounts for approximately 95% of all patients with variegate porphyria in south africa. Heme is a vital molecule for all of the bodys organs, although it is most abundant in the blood, bone marrow, and liver. Epp is due to an inherited deficiency of the enzyme ferrochelatase. Variegate porphyria is found throughout the world, but is particularly common in south africa. Heme is a component of several ironcontaining proteins called hemoproteins, including hemoglobin the protein. Porphyria variegata definition of porphyria variegata by. Though antenatal diagnosis is technically possible, it is not indicated for a relatively benign disorder such as porphyria. This enzyme is critical in the chemical process that leads to haem production. Acute attacks occur in aip, hereditary coproporphyria hcp, vp, and doss porphyria dp. Both sexes are equally affected, the disease does not skip generations and there is frequently a history of the porphyria in other family members. For example, porphyria cutanea tarda is most common in the united states, and variegate porphyria is most common in south.
Scientists have identified genes for all eight enzymes in the heme biosynthetic. Porphyria nord national organization for rare disorders. The exact rates of porphyria are unknown and vary around the world. Oct 17, 2016 acute porphyria biomarkers for disease activity the safety and scientific validity of this study is the responsibility of the study sponsor and investigators. In the case of south african families carrying the common r59w mutation see variegate. Variegate porphyria is caused by a gene mutation of the protoporphyrinogen. Acute porphyria biomarkers for disease activity full text. Variegate porphyria genetic and rare diseases information center.
Although porphyria cant be cured, certain lifestyle changes to avoid triggering symptoms may help you manage. The autosomal dominant acute porphyrias acute intermittent porphyria aip, variegate porphyria vp and hereditary coproporphyria hcp are. Variegate porphyria vp is an inherited disorder of porphyrinheme metabolism arising from mutations of the gene encoding the enzyme protoporphyrinogen oxidase. This deficiency is caused by mutations in the ppox gene, and leads to the accumulation of certain chemicals called porphyrins and porphyrin precursors in the body, which, in turn, can potentially result in a variety of symptoms. Inherited porphyria definition of inherited porphyria by. Variegate porphyria aminolevulinate dehydratase deficiency porphyria all porphyrias produce elevated urine. A collection of disease information resources and questions answered by our genetic and rare diseases information specialists for variegate porphyria. Mar 22, 2017 major types include alad deficiency porphyria, acute intermittent porphyria, congenital erythropoietic porphyria, erythropoietic protoporphyria, hepatoerythropoietic porphyria, hereditary coproporphyria, porphyria cutanea tarda, and variegate porphyria. Variegate porphyria is a rare genetic metabolic disorder characterized by deficient. William was indeed confirmed clinically by three different independent physicians to have variegate porphyria, in accordance with the cutaneous manifestations upon exposure to sunlight and the typical clinical signs. Variegate porphyria vp is a rare metabolic disorder that may present as an acute predominantly motor neuropathy. For example, porphyria cutanea tarda is most common in the united states, and variegate porphyria is most common in south america. Manifestations of variegate porphyria in any given individual may include cutaneous photosensitivity, systemic symptoms arising from neurologic dysfunction, or both.
In addition, some of the following symptoms occur with varying frequency. An increase in porphyrins in the skin result in photosensitivity, ie, the skin is damaged by light. Porphobilinogen pbg 3 excretion in urine increases in acute porphyric attacks, and the measurement of pbg is particularly important in diagnosing the acute porphyrias acute intermittent porphyria, hereditary coproporphyria, and variegate porphyria during the acute stage 7, 8. Variegate porphyria vp is an inherited porphyria characterized by cutaneous blistering andor acute neurovisceral attacks. Acute porphyria biomarkers for disease activity full. Systemic stress, such as liver disease or cholelithiasis, has been noted to precipitate cutaneous symptoms in patients with underlying variegate porphyria. The autosomal dominant acute hepatic porphyrias, acute intermittent porphyria aip, variegate porphyria vp and hereditary. Vp has also been called porphyria variegata, south african genetic. Variegate porphyria is caused by a gene mutation of the protoporphyrinogen oxidase enzyme protein ppox.
Testing cord blood for inheritance of porphyria in the infant. Porphyria is a group of disorders caused by abnormalities in the chemical steps that lead to heme production. Overall, porphyria cutanea tarda is the most common type of porphyria. Variegate porphyria has an autosomal dominant pattern of inheritance. Although these features may also occur on the face and neck as well, it is. Read diagnosis of porphyria in infants and children.
Porphyria is a group of diseases in which substances called porphyrins build up, negatively affecting the skin or nervous system. Variegate porphyria vp is an inherited disorder that is caused by mutations in the ppox gene that lead to the buildup of compounds normally involved in the bodys production of heme. For some forms of porphyria, the prevalence is unknown because many people with a genetic mutation associated with the disease. Clinically overt hepatic porphyria is uncommon in children. The rare homozygous variant of vp is characterized by severe ppox deficiency, onset of photosensitization by porphyrins in early childhood, skeletal. Protoporphyrinogen and coproporphyrinogen accumulate in the liver in variegate porphyria because ppox is deficient, and become oxidized to protoporphyrin and coproporphyrin, which are transported in the blood plasma and cause the skin to be sensitive to sunlight.
Inheritance in man search term variegate porphyria. Robreau am, roberts ag, nordmann y, elder gh, deyback jc. The disorder results from low levels of the enzyme responsible for the seventh step in heme production. The types that affect the nervous system are also known as acute porphyria. The types that affect the nervous system are also known as acute porphyria, as symptoms are rapid in onset and last a short time. Cranial nerves and brainstem functions have been only scarcely studied. Like acute intermittent porphyria aip and hereditary coproporphyria hcp. Dec 17, 2018 variegate porphyria vp is an inherited disorder that is caused by mutations in the ppox gene that lead to the buildup of compounds normally involved in the bodys production of heme. Variegate porphyria article about variegate porphyria by. Dec 20, 2019 variegate porphyria vp is an inherited disorder of porphyrinheme metabolism arising from mutations of the gene encoding the enzyme protoporphyrinogen oxidase.
Variegate porphyria vp is an autosomal dominantly inherited hepatic porphyria. Variegate porphyria genetic and rare diseases information. Hereditary coproporphyria genetic and rare diseases. Dna testing is accurate at any age provided the actual mutation carried in the childs family has been identified. Abdominal pain is the most common complaint in acute intermittent porphyria.
Hereditary coproporphyria hcp is a rare inherited form of liver hepatic porphyria, characterized by neurological symptoms in the form of episodes acute attacks of stomach pain. Variegate porphyria, vp the medical biochemistry page. Autosomal dominant porphyrias include acute intermittent porphyria, most cases of erythropoietic protoporphyria, hereditary coproporphyria, and variegate porphyria. Variegate porphyria is one of the four acute porphyrias, and can present with both blistering cutaneous lesions and acute neurovisceral attacks involving abdominal pain, neuropsychiatric features. Although the gene mutations associated with some cases of porphyria cutanea tarda also have an autosomal dominant inheritance pattern, most people with this form of porphyria do not have an inherited gene mutation. Porphyria cutanea tarda pct is the most common type of porphyria. Classification, inheritance and prevalence of the porphyrias. Variegate porphyria is similar to hereditary coproporphyria, except that there are more severe. Porphyria variegata an overview sciencedirect topics. Protoporphyrinogen and coproporphyrinogen accumulate in the liver in variegate porphyria because ppox is deficient, and become oxidized to. It is considered very uncommon or rare throughout the world apart from in south africa, where it is estimated that 1 in. Heme is a vital molecule for all of the bodys organs, although it is most abundant in the. Jun 25, 2019 variegate thirdperson singular simple present variegates, present participle variegating, simple past and past participle variegated transitive to add variety to something.
Other forms result from inheriting two altered genes, one from each parent autosomal recessive. The most common manifestation of vp is adultonset cutaneous blistering lesions subepidermal vesicles, bullae, and erosions that crust over and heal slowly of sunexposed skin, especially the hands and face. Variegate porphyria is a hepatic form of porphyria. Does anyone have input to royal blood diseasestheres. In people with variegate porphyria activity of the ppox enzyme is reduced by 50%. Porphyria genetic and rare diseases information center. It is an inherited disorder characterised by skin photosensitivity reaction to light, systemic symptoms arising from neurological problems, or both. Variegate porphyria omim 176200, like hereditary coproporphyria, may be associated with acute episodes as seen in acute intermittent porphyria and with photocutaneous manifestations as seen in porphyria cutanea tarda. Although porphyria cant be cured, certain lifestyle changes to avoid triggering symptoms may help you manage it. Variegate porphyria vp american porphyria foundation.
Women may have attacks during the second half of the menstrual cycle when. A 2006 clinical, biochemical and mutational study of eight swiss variegate porphyria patients and their families found four novel ppox gene mutations. People with autosomaldominant acute porphyriasacute intermittent porphyria, variegate porphyria, and hereditary coproporphyriacan present with a sudden lifethreatening crisis. Variegate porphyria is inherited in an autosomal dominant pattern, which means the defective gene is located on an autosome, and inheriting one copy of the defective gene from an affected parent is sufficient to cause the disorder. It is characterized clinically by lifethreatening acute neurovisceral attacks of severe abdominal pain without peritoneal signs, often accompanied by nausea, vomiting, tachycardia, and hypertension. Inheritance of a mutation on a single allele inherited from either mother or from father is sufficient for the disease to manifest. Variegate porphyria right or wrong diagnosis porphyria. Variegate porphyria, also known by several other names, is an autosomal dominant porphyria that can have acute severe but usually not longlasting symptoms along with symptoms that affect the skin. Erythropoietic protoporphyria epp is one of a group of genetic diseases called the porphyrias. More severe cases result from inheriting two copies of the defective gene. Each disease in this family results from deficiencies in a specific enzyme involved in the biosynthesis of heme also called the porphyrin pathway. Here it is due to a founder mutation introduced to. Variegate porphyria is described as a type of porphyria affecting the liver hepatic porphyria, because porphyrin compounds collect in the liver in excessive amounts this mutation.
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