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Porphyrias, Hepatic
Hepatic porphyrias is a form of porphyria in which toxic porphyrin molecules build up in the liver. Hepatic porphyrias can result from a number of different enzyme deficiencies. Examples include (in order of synthesis pathway): * Acute intermittent porphyria * Porphyria cutanea tarda and Hepatoerythropoietic porphyria * Hereditary coproporphyria * Variegate porphyria See also * Erythropoietic porphyria * Givosiran Givosiran, sold under the brand name Givlaari, is a medication used for the treatment of adults with acute hepatic porphyria. Givosiran is a small interfering RNA (siRNA) directed towards delta-aminolevulinate synthase 1 (ALAS1), an important ... References External links * * www.drugs-porphyria.com * www.porphyria-europe.com Porphyrias {{endocrine-disease-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Porphyria
Porphyria is a group of liver disorders in which substances called porphyrins build up in the body, negatively affecting the skin or nervous system. The types that affect the nervous system are also known as acute porphyria, as symptoms are rapid in onset and short in duration. Symptoms of an attack include abdominal pain, chest pain, vomiting, confusion, constipation, fever, high blood pressure, and high heart rate. The attacks usually last for days to weeks. Complications may include paralysis, low blood sodium levels, and seizures. Attacks may be triggered by alcohol, smoking, hormonal changes, fasting, stress, or certain medications. If the skin is affected, blisters or itching may occur with sunlight exposure. Most types of porphyria are inherited from one or both of a person's parents and are due to a mutation in one of the genes that make heme. They may be inherited in an autosomal dominant, autosomal recessive, or X-linked dominant manner. One type, ''porphyria c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Porphyrin
Porphyrins ( ) are a group of heterocyclic macrocycle organic compounds, composed of four modified pyrrole subunits interconnected at their α carbon atoms via methine bridges (=CH−). The parent of porphyrin is porphine, a rare chemical compound of exclusively theoretical interest. Substituted porphines are called porphyrins. With a total of 26 π-electrons, of which 18 π-electrons form a planar, continuous cycle, the porphyrin ring structure is often described as aromatic. One result of the large conjugated system is that porphyrins typically absorb strongly in the visible region of the electromagnetic spectrum, i.e. they are deeply colored. The name "porphyrin" derives from the Greek word πορφύρα (''porphyra''), meaning ''purple''. Complexes of porphyrins Concomitant with the displacement of two N-''H'' protons, porphyrins bind metal ions in the N4 "pocket". The metal ion usually has a charge of 2+ or 3+. A schematic equation for these syntheses is shown: :H2porp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Liver
The liver is a major Organ (anatomy), organ only found in vertebrates which performs many essential biological functions such as detoxification of the organism, and the Protein biosynthesis, synthesis of proteins and biochemicals necessary for digestion and growth. In humans, it is located in the quadrant (anatomy), right upper quadrant of the abdomen, below the thoracic diaphragm, diaphragm. Its other roles in metabolism include the regulation of Glycogen, glycogen storage, decomposition of red blood cells, and the production of hormones. The liver is an accessory digestive organ that produces bile, an alkaline fluid containing cholesterol and bile acids, which helps the fatty acid degradation, breakdown of fat. The gallbladder, a small pouch that sits just under the liver, stores bile produced by the liver which is later moved to the small intestine to complete digestion. The liver's highly specialized biological tissue, tissue, consisting mostly of hepatocytes, regulates a w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acute Intermittent Porphyria
Acute intermittent porphyria (AIP) is a rare metabolic disorder affecting the production of heme resulting from a deficiency of the enzyme porphobilinogen deaminase. It is the most common of the acute porphyrias. Signs and symptoms The clinical presentation of AIP is highly variable and non-specific. The patients are typically asymptomatic, with most gene carriers having no family history because the condition had remained latent for several generations. The syndrome marked by acute attacks affects only 10% of gene carriers. The mean age at diagnosis is 33 years old. Like other porphyrias, AIP is more likely to present in women. A distinguishing feature of AIP that separates it from other porphyrias is the absence of photosensitive cutaneous symptoms that occur in addition to acute attacks. Acute attacks AIP is one of the four porphyrias that presents as an acute attack. 90% of affected individuals never experience an acute attack and are asymptomatic, while an estimated 5% of a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Porphyria Cutanea Tarda
Porphyria cutanea tarda is the most common subtype of porphyria. The disease is named because it is a porphyria that often presents with skin manifestations later in life. The disorder results from low levels of the enzyme responsible for the fifth step in heme production. Heme is a vital molecule for all of the body's organs. It is a component of hemoglobin, the molecule that carries oxygen in the blood. Hepatoerythropoietic porphyria has been described as a homozygous form of porphyria cutanea tarda, although it can also be caused if two different mutations occur at the same locus. Symptoms and signs Porphyria cutanea tarda (PCT) is recognized as the most prevalent subtype of porphyritic diseases. PCT is characterized by onycholysis and blistering of the skin in areas that receive higher levels of exposure to sunlight. The primary cause is a deficiency of uroporphyrinogen decarboxylase (UROD), a cytosolic enzyme that is a step in the enzymatic pathway that leads to the synthes ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hepatoerythropoietic Porphyria
Hepatoerythropoietic porphyria is a very rare form of hepatic porphyria caused by a disorder in both genes which code Uroporphyrinogen III decarboxylase (UROD). It has a similar presentation to porphyria cutanea tarda (PCT), but with earlier onset. In classifications which define PCT type 1 as "sporadic" and PCT type 2 as "familial", hepatoerythropoietic porphyria is more similar to type 2. See also * Hereditary coproporphyria * List of cutaneous conditions * List of dental abnormalities associated with cutaneous conditions Many conditions of or affecting the human integumentary system have associated abnormalities of the teeth. See also * List of cutaneous conditions * List of contact allergens * List of cutaneous conditions associated with internal maligna ... References External links * * Porphyrias Skin conditions resulting from errors in metabolism {{endocrine-disease-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hereditary Coproporphyria
Hereditary coproporphyria (HCP) is a disorder of heme biosynthesis, classified as an acute hepatic porphyria. HCP is caused by a deficiency of the enzyme coproporphyrinogen oxidase, coded for by the ''CPOX'' gene, and is inherited in an autosomal dominant fashion, although homozygous individuals have been identified. Unlike acute intermittent porphyria, individuals with HCP can present with cutaneous findings similar to those found in porphyria cutanea tarda in addition to the acute attacks of abdominal pain, vomiting and neurological dysfunction characteristic of acute porphyrias. Like other porphyrias, attacks of HCP can be induced by certain drugs, environmental stressors or diet changes. Biochemical and molecular testing can be used to narrow down the diagnosis of a porphyria and identify the specific genetic defect. Overall, porphyrias are rare diseases. The combined incidence for all forms of the disease has been estimated at 1:20,000. The exact incidence of HCP is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Variegate Porphyria
Variegate porphyria, also known by several other names, is an autosomal dominant porphyria that can have acute (severe but usually not long-lasting) symptoms along with symptoms that affect the skin. The disorder results from low levels of the enzyme responsible for the seventh step in heme production. Heme is a vital molecule for all of the body's organs. It is a component of hemoglobin, the molecule that carries oxygen in the blood. Signs and symptoms When symptoms occur, they can include acute attacks (similar to acute intermittent porphyria) or skin damage. Acute attacks usually begin in adulthood and cause abdominal pain, vomiting, diarrhoea and constipation. During an attack, a person may also experience muscle weakness, seizures, and mental changes such as anxiety and hallucinations. These signs and symptoms are triggered by nongenetic factors such as certain drugs, dieting or fasting, certain hormones and stress. Some people with variegate porphyria have ski ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Erythropoietic Porphyria
Erythropoietic porphyria is a type of porphyria associated with erythropoietic cells. In erythropoietic porphyrias, the enzyme deficiency occurs in the red blood cells. Types There are three types: Presentation X-linked dominant erythropoietic protoporphyria is a relatively mild version of porphyria with the predominant symptom being extreme photosensitivity causing severe itching and burning sensation of the skin due to the buildup of protoporphyrin IX. One possible treatment was discovered when treating an individual with supplemental iron for a gastric ulcer. Levels of free protoporphyrin decreased significantly as there was iron available for the FECH to produce heme. Levels of zinc-protoporphyrin, however did not decrease. Cause X-linked sideroblastic anemia or "X-linked dominant erythropoietic protoporphyria", associated with ALAS2 (aminolevulinic acid synthase), has also been described. X-linked dominant erythropoietic protoporphyria (XDEPP) is caused by a gain of func ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Givosiran
Givosiran, sold under the brand name Givlaari, is a medication used for the treatment of adults with acute hepatic porphyria. Givosiran is a small interfering RNA (siRNA) directed towards delta-aminolevulinate synthase 1 (ALAS1), an important enzyme in the production of heme. The most common side effects include nausea and injection site reactions. The U.S. Food and Drug Administration (FDA) considers it to be a first-in-class medication. Medical uses Givosiran is indicated for the treatment of adults with acute hepatic porphyria, a genetic disorder resulting in the buildup of toxic porphyrin molecules which are formed during the production of heme (which helps bind oxygen in the blood). History In November 2019, givosiran was approved in the United States for the treatment of adults with acute hepatic porphyria (AHP). Efficacy was evaluated in ENVISION (NCT03338816), a randomized, double‑blind, placebo‑controlled, multinational trial enrolling 94 participants wi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
