Porphyria cutanea tarda (PCT) is a relatively common hepatic porphyria, which mainly affects the skin. Liver disease are also common. PCT is an acquired or inherited deficiency in the activity of hepatic Uroporphyrinogen decarboxylase, an enzyme of the heme biosynthetic pathway (see Table: substrates and enzymes of the heme biosynthesis and the data associated with the deficiency diseases) due. Porphyrins collect itself, especially in oxidative stress in hepatocytes, which is usually due to an increased iron content in the liver, but can also be caused by alcohol, smoking, estrogen or hepatitis C or HIV infection. Symptoms include fragile, easily blistering skin, especially on sun-exposed areas. The diagnosis is made by Porphyrinanalyse in urine and feces. Differentiation between the acute cutaneous porphyria, hereditary coproporphyria and porphyria variegata is important. The treatment includes reduction of iron by means of blood-letting and complementary porphyrin by treatment with low doses of chloroquine or hydroxychloroquine. A prevention is made by avoiding sunlight, alcohol, smoking, estrogens and iron-containing drugs, and the successful treatment of concomitant hepatitis C and HIV infection.
Porphyria cutanea tarda (PCT) is a relatively common hepatic porphyria, which mainly affects the skin. Liver disease are also common. PCT is an acquired or inherited deficiency in the activity of hepatic Uroporphyrinogen decarboxylase, an enzyme of the heme biosynthetic pathway (see Table: substrates and enzymes of the heme biosynthesis and the data associated with the deficiency diseases) due. Porphyrins collect itself, especially in oxidative stress in hepatocytes, which is usually due to an increased iron content in the liver, but can also be caused by alcohol, smoking, estrogen or hepatitis C or HIV infection. Symptoms include fragile, easily blistering skin, especially on sun-exposed areas. The diagnosis is made by Porphyrinanalyse in urine and feces. Differentiation between the acute cutaneous porphyria, hereditary coproporphyria and porphyria variegata is important. The treatment includes reduction of iron by means of blood-letting and complementary porphyrin by treatment with low doses of chloroquine or hydroxychloroquine. A prevention is made by avoiding sunlight, alcohol, smoking, estrogens and iron-containing drugs, and the successful treatment of concomitant hepatitis C and HIV infection. Pathophysiology for etiology and pathophysiology of porphyria, porphyria overview. PCT is due to a deficiency of hepatic Uroporphyrinogen decarboxylase (UROD-see Table: substrates and enzymes of the heme biosynthesis and the problems associated with their lack of diseases). Porphyrins accumulate in the liver and be transported to the skin, where they cause a photosensitivity. The partially (~ 50%) deficiency in UROD activity in heterozygous patients themselves is not sufficient to cause biochemical or clinical features of the PCT. Additional factors (z. B. increase of the iron content in the liver, alcohol use, exposure to halogenated hydrocarbon, hepatitis C virus or HIV infection) are required to cause> 75% decrease in hepatic UROD activity, for manifestation of features of the PCT are needed. These factors increase the oxidation of Uroporphyrinogenen and other porphyrinogens to the corresponding porphyrins and also help inhibitors of UROD to form. The medications that normally an acute porphyria (see Table: Drugs and Porphyria *) trigger, no trigger for a PCT. Liver disease is often at a PCT, and can be triggered in part by a Porphyrinakkumulation, a chronic hepatitis C infection, concurrent hemosiderosis or binge drinking. Cirrhosis of the liver occurs with ? 35% of patients and hepatocellular carcinoma from 7 to 24% (more common in males mean age). There are two main types of PCT: type 1 (acquired or sporadic) and type 2 (hereditary or familial). Type 1 accounts for 75-80% of cases and type 2 20-25%. Type 3 accounts for <1% of cases. In the Type 1 PCT the Decarboxylasestörung is confined to the liver and there is no genetic disease system. It manifests itself usually in middle age or later. In the type 2, the PCT Decarboxylasestörung is autosomal dominant with reduced penetrance. The disorder occurs in all cells, including red blood cells on. You may develop earlier than the Type 1, sometimes in childhood. The partially (~ 50%) deficiency in UROD activity in heterozygous patients themselves is not sufficient to cause biochemical or clinical features of the PCT. Additional factors (z. B. increase of the iron content in the liver, alcohol use, exposure to halogenated hydrocarbon, hepatitis C virus or HIV infection) are required to cause> 75% decrease in hepatic UROD activity, for manifestation of features of the PCT are needed. These factors increase the oxidation of Uroporphyrinogenen and other porphyrinogens to the corresponding porphyrins and also help inhibitors of UROD to form. The hepatoerythropoietische porphyria (HEP-see table: Some less common porphyria) comprising a profound UROD deficiency is very rare and is often seen as an autosomal recessive form of type 2 PCT. Type 3 PCT, which is very rare, hereditary, but no defect in UROD gene; a defect in another, unidentified gene appears to be the cause. Types 1 and 2 are the main forms of the disease. They have the same precipitant, symptoms and treatment. The overall prevalence may be in the order of 1 / 10,000, but is likely to be higher in people who halogenated aromatic hydrocarbons or other precipitating agents of the disease are exposed. Pseudoporphyria kidney failure, ultraviolet radiation (UVA) and certain medications can PCT-like symptoms without increased porphyrin levels cause (pseudoporphyria). Frequently involved medications are furosemide, tetracyclines, sulfonamides and naproxen and other NSAIDs. Since porphyrins can be poorly dialyse some patients develop a skin condition that is very similar to the one in PCT after years of hemodialysis; This skin condition is called pseudoporphyria of ESRD. Symptoms and signs Patients with PCT show especially on sun-exposed a fragile skin texture. The phototoxicity occurs later: Patients do not always a link between sun exposure and the onset of symptoms forth. Porphyria cutanea tarda (earlobe) © Springer Science + Business Media var model = {thumbnailUrl: ‘/ – / media / manual / professional / images / 495 porphyria-cutanea-tarda-ear-lobe-slide-10-springer-high_de. jpg lang = en & thn = 0 & mw = 350 ‘, imageUrl’? /-/media/manual/professional/images/495-porphyria-cutanea-tarda-ear-lobe-slide-10-springer-high_de.jpg?la=de&thn = 0 ‘, title:’ porphyria cutanea tarda (earlobe), ‘description’ u003Ca id = “v37895499 ” class = “”anchor “” u003e u003c / a u003e u003cdiv class = “”para “” u003e u003cp u003ePorphyria cutanea tarda mainly affects sun-exposed areas