Geometry.Net - Health_Conditions: Porphyrias

DIAGNOSING THE PORPHYRIAS
An article by Thomas G. DeLoughery, Associate Professor of Medicine.Category Health Conditions and Diseases porphyrias DIAGNOSING THE porphyrias. REFERENCES. Desnick RJ and Anderson KE. Heme biosynthesisand its abnormalities the porphyrias and sideroblastic anemia.
http://www.ohsu.edu/som-hemonc/handouts/deloughery/por.shtml

Extractions: DIAGNOSING THE PORPHYRIAS DIAGNOSIS The key to diagnosis is suspicion of the disease, but this must be tempered by the fact that these are rare diseases. The first line of action is to screen the urine for the presence of porphyrin precursors, delta-aminolevulinic acid (ALA) and porphobilinogen (PBG). These substances are always present if the patient is having an acute neurovisceral attack. Most patients with latent AIP and some with latent HC and VP will have elevated levels. If the urine screen is negative, then one can safely eliminate porphyria as a cause of acute neurovisceral symptoms. Abnormal urine screens should be verified by quantitative measures of urine ALA, PBG and porphyrins. Most elevated urine porphyrins on screening tests are false positives, mainly due to rises in coproporphyrin excretion seen with alcohol users, liver disease, acute illness, etc.., and not porphyria. The diagnosis of HC or VP is demonstrated by increased levels of porphyrins in the urine and stool. The vast majority of patients with HC have extreme elevations levels of coproporphyrin in their stool - 5 to 100 times normal. Patients with VP have elevated stool coproporphyrin and protoporphyrin. Patients with PCT have elevated stool isocoproporphyrin and protoporphyrin and increased urine coproporphyrin and uroporphyrin. Minor elevations of urine and stool porphyrins (espcially coproporphyrins) are common and non-specific.
Porphyrias: Clinical Manifestations, Diagnosis And Treatment MEDSTUDENTS-METABOL
Clinical manifestations, diagnosis, etiology and treatment of six types of porphyrias are discussed.
http://www.medstudents.com.br/metdis/metdis3.htm

Extractions: Medstudents' Homepage Porphyrias are inherited or adquired diseases that result from an abnormal metabolism of heme biosynthesis pathway. The main causes are enzyme deficiencies that lead to heme pathways intermediates accumulation. Heme biosynthesis occurs almost entirely in the liver and bone marrow and is composed by eight reactions, each one of these being catalyzed by an especific enzyme. Therefore, partial or complete deficiency of one of these enzymes result in diferents clinical pictures. We will focus our discussion mainly on clinical grounds. There are two major groups of porhyrias according to the site where dysfunction occurs, i.e, hepatic and erythropoietic porphyrias. Among erythropoietic types, there are: Congenital Erythropoietic Porphyria and Protoporphyria. Hepatic porphyrias are: Intermitent Acute Porphyria, Hereditary Coproporphyria, Variegate Porphyria and Porphyria Cutanea Tarda. It is important to recognize that the three most common types of porphyrias are Intermitent Acute Porphyria (IAP), Porphyria Cutanea Tarda (PCT) and Protoporphyria (PP). Intermitent Acute Porphyria: The majority of patients are assymptomatic. Signs and symptoms rarely start before puberty. The initial and commonest manifestation is abdominal pain, which can be diffuse or localized, colicky. The clinical picture may mimic an accute inflammatory abdominal disease. It is caused by an altered autonomic activity. Peripheral neuropathy is primarily motor, beginning in proximal muscles, more often in the arms. Cranial nerves manifestations my lead to optic nerve atrophy. CNS abnormalities include seizures, delirium and coma. Hepatic dysfunctions are common. Precipitating factors are drugs as barbiturates, sulfonamides, estrogens and dietary restriction of carbohydrates. Diagnosis is made on clinical grounds and increased erythrocytic and urinary porphobilinogen and aminolevolinic acid (ALA) levels (metabolic intermediates of heme).
THE MERCK MANUAL, Sec. 2, Ch. 14, The Porphyrias
General. The porphyrias A group of disorders cause by deficiencies of enzymes of the heme biosynthetic pathway.
http://www.merck.com/pubs/mmanual/section2/chapter14/14a.htm

Extractions: This Publication Is Searchable The Merck Manual of Diagnosis and Therapy Section 2. Endocrine And Metabolic Disorders Chapter 14. The Porphyrias Topics [General] Most Common Porphyrias Less Common Porphyrias [General] The porphyrias: A group of disorders cause by deficiencies of enzymes of the heme biosynthetic pathway. Abnormally elevated levels of porphyrins or their precursors (eg, -aminolevulinic acid [ALA] and porphobilinogen [PBG]) are produced, accumulate in tissues, and are excreted in urine and stool. Disease manifestations result almost entirely from effects on the nervous system and skin. The Heme Biosynthetic Pathway Heme, an iron-containing pigment, is the nonprotein functional component of hemoproteins, which are found in all tissues. The heme biosynthetic pathway is illustrated in Fig. 14-1. The eight different enzymes that drive the sequential steps in this pathway are numbered 1 through 8 in Fig. 14-1 and are briefly described below. The first enzyme and the last three are found in mitochondria; the intermediate enzymes occur in the cytosol. ALA dehydratase, a cytosolic enzyme, converts two molecules of ALA into a monopyrrole, PBG, with the removal of two molecules of water. Lead inhibits ALA dehydratase activity by displacing zinc (the metal essential for enzyme activity) from the enzyme. The most potent inhibitor of the enzyme is succinylacetone, a structural analog of ALA, which is found in urine and blood of patients with hereditary tyrosinemia.
MEDIC: CLINICAL HANDBOOK
porphyrias. porphyrias are a group of disorders caused by deficiencies of enzymes involved in the synthesis of heme.
http://medic.med.uth.tmc.edu/path/00000884.htm

Extractions: Porphyrias are a group of inherited disorders of heme synthesis. Only one normal gene is present to produce a key functional enzyme in heme synthesis. This results in at least a 50% of the normal enzyme activity. This reduced level of enzyme results in a build up of precursors behind the deficient enzyme which then accumulate in body fluids and tissues. The clinical manifestations, cutaneous lesions, neurologic dysfunction, and hepatic disease, characteristic to each type of porphyria are due to the toxic nature of these precursor compounds. delta - Aminolevulinic Acid (ALA) dehydrase deficiency Acute Intermittent porphyria Congenital erythropoietic porphyria Porphyria cutanea tarda Hepatoerythropoietic porphyria ... Protoporphyria Laboratory Diagnosis Summary
MEDLINEplus Medical Encyclopedia: Porphyria
The porphyrias may be inherited as either autosomal dominant (caused by inheriting one abnormal copy of the gene) or
http://www.nlm.nih.gov/medlineplus/ency/article/001208.htm

Extractions: Skip navigation Other encyclopedia topics: A-Ag Ah-Ap Aq-Az B-Bk ... Z Contents of this page: Porphyria cutanea tarda on the hands Alternative names Return to top Acute intermittent porphyria; Hereditary coproporphyria; Congenital erythropoietic porphyria; Erythropoietic protoporphyria Definition Return to top Porphyria is a group of inherited disorders involving abnormalities in the production of heme pigments (the base material responsible for hemoglobin (red blood cell pigment), myoglobin (reddish muscle cell pigment) and another group of materials called cytochromes. Porphyrias are characterized by three major findings: photodermatitis ( light sensitivity causing rashes ), neuropsychiatric complaints, and visceral complaints (e.g., abdominal pain , cramping). Causes, incidence, and risk factors Return to top The porphyrias may be inherited as either autosomal dominant (caused by inheriting one abnormal copy of the gene) or autosomal recessive (requires inheritance of two abnormal genes) traits depending on which type of porphyria is involved. Some types of porphyria have their onset in early childhood, some at puberty, and others during adulthood.
THE PORPHYRIAS
THE porphyrias Ed Friedlander, MD, Pathologist erf@uhs.edu. QUIZBANK Metabolic 's 112114. Learning objectives. Recognize the common porphyrias.
http://www.pathguy.com/lectures/porphyri.htm

Extractions: erf@uhs.edu Cyberfriends: The help you're looking for is probably here. Welcome to Ed's Pathology Notes, placed here originally for the convenience of medical students at my school. You need to check the accuracy of any information, from any source, against other credible sources. I cannot diagnose or treat over the web, I cannot comment on the health care you have already received, and these notes cannot substitute for your own doctor's care. I am good at helping people find resources and answers. If you need me, send me an E-mail at erf@uhs.edu Your confidentiality is completely respected. Allan N. Spreen MD also handles internet questions at no charge, with a primary focus on nutrition. Dr. Spreen is also my former student and my close friend. DoctorGeorge.com is a larger, full-time service. There is also a fee site at myphysicians.com , and another at www.afraidtoask.com Translate this page automatically With one of four large boxes of "Pathguy" replies. I'm still doing my best to answer everybody. Sometimes I get backlogged, sometimes my E-mail crashes, and sometimes my literature search software crashes. If you've not heard from me in a week, post me again. I send my most challenging questions to the medical student pathology interest group, minus the name, but with your E-mail where you can receive a reply.
EPP Frames
Short for Erythropoetic ProtoPorhyria, which is a rare metabolic disease. A personal site about this disorder, one of the family of porphyrias.
http://members.tripod.com/~Alzuko/epp.htm
Porphyrias: Clinical Manifestations, Diagnosis And Treatment MEDSTUDENTS-METABOL
METABOLIC DISORDERS. Bernardo Haddock Lobo Goulart Samanta Teixeira Basto.Medstudents' Homepage. Hemochromatosis. Definition. Hemochromatosis
http://www.medstudents.com.br/metdis/metdis4.htm

Extractions: Medstudents' Homepage Hemochromatosis is a disease due to increased iron absorption that leads to accumulation of iron in diverse tissues. It can be hereditary (primary hemochromatosis) or secondary to chronic anemias as ß-thalassemias (ineffective erythropoiesis leading to increased erythrocitic destruction) or defects in hemoglobin synthesis ( as in porphyria cutanea tarda) ;multiple transfusion therapy ;or others less common conditions. Iron absorption from the gut occurs normally in a rate of 1 mg per day. In hemochromatosis this absortion reaches the rate of 4 to 5 mg/d and there is a progressive accumulation to 15 to 40 grams of body iron (normal ~ 2 to 3 g). Thus, the disease develops in men above age 20 and postmenopausal women, due to stopping in iron loss in menses. The iron accumulates in every tissue of the body, but main clinical manifestations are secondary to iron deposition in: Liver, thyroid, hypothalamus, heart, pancreas, gonads and joints. Many patients are asymptomatic. Common symptoms are fatigue, arthalgias, impotence, amenorrhea and palpitations. The most characteristical clinical manifestation occur in the liver because the portal circulation filters the iron initially absorbed fom the gut. Usually patients develop cirrhosis. Heart manifestations include arrythmias and disturbances of conduction. Skin adquires an diffuse hyperpigmentation mainly in scars, sun exposed and unexposed areas and genitalia. Arthropathy occurs in wrists, hips, knees and ankles. To distinguish this arthopathy from others, searching for initial involvement of second and third metacarpophalangeal joints is helpful. Hypogonadism hipogonadothrofic is secondary to iron deposition in hypophisary cells and leads to loss of libido, amenorrhea, impotence and body hair losing. Diabetes Mellitus results from pancreatic accomitment and the signs and symptons, as the treatment, do not differ from conventional diabetes.
Katalog - Wirtualna Polska
Serwis Katalog w Wirtualna Polska S.A. pierwszy portal w Polsce.
http://katalog.wp.pl/DMOZ/Health/Conditions_and_Diseases/Nutrition_and_Metabolis

Extractions: Poczta Czat SMS Pomoc Szukaj.wp.pl: -Katalog -Polskie www -¦wiatowe www -Wirtualna Polska -FTP/Pliki -Grupy dyskusyjne -Encyklopedia -Produkty wp.pl Katalog Katalog ¦wiatowy DMOZ ... Conditions and Diseases > Nutrition and Metabolism Disorders Fakty o Katalogu Pomoc Regulamin Serwis szukaj ... Ostatnio dodane
THE MERCK MANUAL--Home Edition, Sec. 12, Ch. 141, Porphyrias
Chapter 141. porphyrias. porphyrias are a group of disorders causedby deficiencies of enzymes involved in the synthesis of heme.
http://www.merck.com/pubs/mmanual_home/sec12/141.htm

Extractions: The Merck Manual of Medical InformationHome Edition Section 12. Disorders of Nutrition and Metabolism Chapter 141 Porphyrias Porphyrias are a group of disorders caused by deficiencies of enzymes involved in the synthesis of heme. Heme, a chemical compound that carries oxygen and makes blood red, is a key component of hemoproteins, a type of protein found in all tissues. The largest amount of heme is synthesized in the bone marrow for manufacturing hemoglobin. The liver also produces large amounts of heme, and most is used as a component of cytochromes. Some cytochromes in the liver oxidize foreign chemicals, including drugs, so that they are more easily removed from the body. Eight different enzymes drive the sequential steps in heme synthesis. When an enzyme in the pathway of heme production is deficient, chemical precursors of heme may accumulate in tissues (especially in the bone marrow or liver). These precursors, which include delta-aminolevulinic acid, porphobilinogen, and porphyrins, then appear in the blood and are excreted in the urine or stool. Excess porphyrins cause photosensitivity, in which a person is overly sensitive to sunlight. This occurs because when exposed to light and oxygen, porphyrins generate a charged, unstable form of oxygen that can damage the skin. Nerve damage, leading to pain and even paralysis, occurs in some porphyrias, especially when delta-aminolevulinic acid and porphobilinogen accumulate.
THE PORPHYRIAS
The porphyrias. © Dr. Maged N. Kamel MediCAD Multimedia, 1995-98.All rights reserved. http//www.medicad.com. Acronyms AIP, Acute
http://www.geocities.com/stantonios/mc/porphyria.html

Extractions: The Porphyrias http://www.medicad.com Acronyms: AIP, A cute I ntermittent P orphyria; CEP, C ongenital E rythropoietic P orphyria; PCT, P orphyria C utanea T arda; HEP, H epato e rythropoietic P orphyria; HCP, H ereditary C opro p orphyria; VP, V ariegate P orphyria; EPP, E rythropoietic P roto p orphyria Mechanism of porphyrin-induced photosensitivity: The photosensitivity of the skin in porphyria is due to porphyrins absorbing ultraviolet radiation in the 400 nm range and emitting an intense red fluorescence. Porphyrins, when irradiated with light of the appropriate wavelength in the presence of oxygen, will cause photodynamic effects. Light energy absorbed by the porphyrin raises electrons into an excited state. Energy released on return of the molecule to its original state reacts with oxygen to produce free radicals and singlet oxygen (O) which damages molecules, cells and tissues. Unsaturated lipids are particular targets for activated oxygen species; cell damage results from the resulting plasma membrane and lysosomal membrane injury and also from complement activation. b -Carotene, a known quencher of free radicals and singlet oxygen, has a photoprotective effect in porphyria.
Cheryl Ann's Porphyria Links
The porphyrias Home. Links. Disclaimer. Center For Study of Disorders of Iron andPorphyrin Metabolism. Human porphyrias Page. Index of Porphyrin Labs Worldwide.
http://www.geocities.com/porphyria2000/porphs.htm
Porphyrias
porphyrias may be divided into two major types erythropoietic porphyria and Hepaticporphyria. porphyrias (pronounce) may be divided into two major types.
http://www.stargine.com/porphyrins/Heme_iron/porphyrins/_phyrias.html
A Selection Of Books About Porphyrias
Go to site. porphyrias the books. Other Macalpine, The porphyrias J. LyndalYork,
http://www.stargine.com/porphyrins/Mediporph/porphyria_books.html
Porphyrias
porphyrias. porphyrias (pronounce) may be divided into two major types. Erythropoieticporphyria is a defect of porphyrin metabolism of bloodproducing tissues.
http://www.mcphu.edu/netbiochem/hi6.htm
Medic-Planet Porphyrias
porphyrias See also Brain, Digestive system, Genetic diseases, Liver,Mental illnesses, Nervous system, Skin, Back to the Index page
http://www.medic-planet.com/MP_article/internal_reference/Porphyrias
The Porphyrias
The porphyrias.
http://www.indstate.edu/thcme/mwking/porphyrias.html
Porphyrias
porphyrias are a group of defects in the heme synthesis leading to theaccumulation of some precursors and to characteristic symptoms.
http://erasmeinfo.ulb.ac.be/globule/English/porphyrias.htm

Extractions: Porphyrias are a group of defects in the heme synthesis leading to the accumulation of some precursors and to characteristic symptoms. Two kinds of clinical presentations are seen (together or separately): acute crises (abdominal and neurological signs) cutaneous lesions (skin fragility and photosensitivity) Last Update: Webmaster
The Porphyrias
The porphyrias. Congenital Erythropoietic Porphyria (CEP); ErythropoieticProtoporphyria (EPP); ALA Dehydratase Deficiency Porphyria (ADP);
http://www.dentistry.leeds.ac.uk/biochem/thcme/porphyrias.html
Porphyrias
MAIN SEARCH INDEX porphyrias. of that specific precursor. This situationis the main characteristic of the porphyrias. Owing to a
http://www.hendrickhealth.org/healthy/001095.htm

Extractions: Resources The porphyrias are disorders in which the body produces too much porphyrin and insufficient heme (an iron-containing nonprotein portion of the hemoglobin molecule). Porphyrin is a foundation structure for heme and certain enzymes. Excess porphyrins are excreted as waste in the urine and stool. Overproduction and overexcretion of porphyrins causes low, unhealthy levels of heme and certain important enzymes, creating various physical symptoms. Biosynthesis of heme is a multistep process that begins with simple molecules and ends with a large, complex heme molecule. Each step of the chemical pathway is directed by its own task-specific protein, called an enzyme. As a heme precursor molecule moves through each step, an enzyme modifies the precursor in some way. If a precursor molecule is not modified, it cannot proceed to the next step, causing a buildup of that specific precursor. This situation is the main characteristic of the porphyrias. Owing to a defect in one of the enzymes of the heme biosynthesis pathway, protoporphyrins or porphyrins (heme precursors) are prevented from proceeding further along the pathway. These precursors accumulate at the stage of the enzyme defect causing an array of physical symptoms in an affected person. Specific symptoms depend on the point at which heme biosynthesis is blocked and which precursors accumulate. In general, the porphyrias primarily affect the skin and the nervous system. Symptoms can be debilitating or life threatening in some cases. Porphyria is most commonly an inherited condition. It can also, however, be acquired after exposure to poisonous substances.

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