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R von Tiepermann

Publications and source records attributed to R von Tiepermann.

12 recordsLinked to original sources
PubMed1984

Development of chronic hepatic porphyria (porphyria cutanea tarda) with inherited uroporphyrinogen decarboxylase deficiency under exposure to dioxin.

Exposure to dioxin triggered a clinically manifest chronic hepatic porphyria (porphyria cutanea tarda) in two patients (brother and sister) with hereditary uroporphyrinogen decarboxylase deficiency. The patients showed a decrease of erythrocyte uroporphyrinogen decarboxylase activity to approximately 50% of controls even in reinvestigations after three years, whereas clinical symptoms and porphyrinuria had improved considerably. Only a subclinical phase of chronic hepatic porphyria persisted. Subnormal uroporphyrinogen decarboxylase activity could be determined in altogether nine family members. The remission of porphyria cutanea tarda into a subclinical phase occurred after chloroquine therapy. Subclinical phases of chronic hepatic porphyria (type A) in other family members remitted without special therapy. Among the 60 persons dioxin-exposed by the Seveso accident, a secondary coproporphyrinuria was found in 22% of examined patients with transition to a subclinical chronic hepatic porphyria in 5 cases. The changes had subsided completely after one year. A persistence of the transition state in 3 cases is probably due to alcohol influence. None of these cases developed a porphyria cutanea tarda. The investigations showed that a hereditary disposition is necessary for biochemical and clinical expression of chronic hepatic porphyria after a unique dioxin exposure. This is not given in the sporadic cases: after a unique dioxin exposure they indeed develop a symptomatic disturbance of porphyrin metabolism but not a clinically relevant chronic hepatic porphyria. We conclude that a unique acute exposure to dioxin can trigger the chronic hepatic porphyria disease process in persons with an underlying genetic abnormality of uroporphyrinogen decarboxylase.

Adult↗
PubMed1981

Alcohol-induced decrease in uroporphyrinogen decarboxylase activity in rat liver and spleen.

Chronic alcohol consumption in rats leads to a decrease in uroporphyrinogen decarboxylase activity in liver and spleen, associated with a pathologic porphyrinuria. These findings show the toxic effect of alcohol in the biochemical pathogenesis of chronic hepatic porphyria. The results confirm experimentally the transition of symptomatic coproporphyrinuria to chronic hepatic porphyria as observed in man, and the progression of biochemical phases of chronic hepatic prophyria into the clinical phase, i.e., the development from latent to manifest stages under chronic alcohol ingestion.

Alcoholism↗
PubMed1980

Uroporphyrinogen decarboxylase deficiency in experimental chronic hepatic porphyria.

During hexachlorobenzene feeding of rats the following biochemical signs of a chronic hepatic porphyria developed: porphyrinuria with increase of uro- and hexacarboxyporphyrin, hepatic prophyrin accumulation of uro- and heptacarboxyporphyrin and a diminished activity of uroporphyrinogen decarboxylase in the liver, but nut in the red cells. During the 5.3 days of the intoxication the behaviour of metabolite constellation and enzyme activities was inverse. Hexachlorobenzene porphyria in rats is a pathobiochemical model of chronic hepatic prophyria, which in man becomes clinically manifest as porphyria cutanea tarda.

Animals↗
PubMed1979

New type of hepatic porphyria with porphobilinogen synthase defect and intermittent acute clinical manifestation.

In two young patients with acute hepatic porphyria syndrome and persisting paralyses, which increased in intensity during intermittent occurring crisis, the activity of erythrocyte porphobilinogen synthase (delta-aminolevulinic acid dehydratase) was found to be considerably diminished, below 1% of the value of normal control persons. In contrast, the activity of uroporphyrinogen synthase was normal. Both patients have been excreting high quantities of delta-aminolevulinic acid and porphyrins in urine for years. Lead intoxication has definitively been excluded. Since the relatives also show lower activities in porphobilinogen synthase, the disease of these two patients is probably a new enzymatic type of inherited acute hepatic porphyria, the excretion profile of which is qualitatively completely different from those of the known acute porphyrias. The discovery of this porphyria confirms the theory of overlapping transition in the biochemical and clinical symptoms and analogies among acute hepatic porphyrias.

Acute Disease↗
PubMed1978

[Uroporphyrinogen synthase in erythrocytes in acute intermittent porphyria: new pathobiochemical aspects (author's transl)].

Uroporphyrinogen synthase (EC 4.3.1.8) was determined in the erythrocytes of 380 patients, of which 21 showed clinical symptoms of acute intermittent porphyria. The normal range of a random sample was 61 +/- 23 mumol/1.h(x +/- 2s, n=302), including the activity of uroporphyrinogen cosynthase and the subsequent enzymes; when all the latter enzymes were destroyed by heating the haemolysate, the normal range for uroporphyrinogen synthase was 65 +/- 25 mumol/1.h(x +/- 2s, n=274). The respective activity of uroporphyrinogen synthase in patients with acute intermittent porphyria was 35 +/- 12, and 40 +/- 18 mumol/1.h which was significantly lower (p less than 0.001) than the control values. In the 21 cases of acute intermittent porphyria, the diagnosis had already been made from the presence of porphyrin precursors and porphyrin in the urine. In 7 of the 21 cases of acute intermittent porphyria, and in 6 relatives of the patients, the activity of the uroporphyrinogen synthase was in the overlap zone (40-50 mumol/1.h). 32 relatives of 9 of the patients with acute intermittent porphyria were investigated: 22 showed a significant decrease of uroporphyrinogen synthase, and 7 of these showed pathological urinary porphyrin precursors and porphyrin. The relative activity of uroporphyrinogen synthase in patients with acute intermittent porphyria was 57%. A decrease of the uroporphyrinogen synthase activity of greater than 30% compared with the mean of the controls is a sure indicator for the presence of a primary enzymic defect in the gene carrier for acute intermittent porphyria.

Acute Disease↗
PubMed1978

[Uroporphyrinogen decarboxylase in erythrocytes: studies on the primary genetic enzyme defect in chronic hepatic porphyria (author's transl)].

In chronic hepatic porphyria, including the clinical phase, porphyria cutanea tarda, the activity of uroporphyrinogen decarboxylase is decreased not only in the liver, but also in the erythrocytes. The synonomous decrease in the enzymic activity in liver and erythrocytes in both familial and sporadic hepatic porphyria shows that the disturbance of this enzyme is the primary genetic defect of this condition; inheritance of the defect is probably autosomal and dominant. The clinical manifestation of disturbances of porphyrin metabolism are precipitated, however, by additional factors, such as liver damage, alcohol, oestrogens and neoplastic growths. In the absence of these other pathogenic influences, the enzyme defect is compensated and does not result in disturbances of haem or haemoglobin synthesis, either in the liver or the bone marrow.

Carboxy-Lyases↗