Congenital erythropoietic porphyria (CEP) is one of the rarest autosomal-recessive disorders of the porphyrin metabolism caused by the homozygous defect of uroporphyrinogen III cosynthase. High amounts of uroporphyrin I accumulate in all cells and tissues, reflected by an increased erythrocyte porphyrin concentration and excretion of high porphyrin amounts in urine and feces. Dermal deposits of...

Porphyria cutanea tarda is thought to result from an inherited deficiency of uroporphyrinogen decarboxylase (EC 4.1.1.37) in some patients. Present methods for determining uroporphyrinogen decarboxylase activity are time consuming, so we examined the pattern of porphyrins formed from porphobilinogen by hemolysates as a possible marker for hereditary porphyria cutanea tarda. After the hemolysate...

Urine is the most frequent specimen used in the initial evaluation of adult patients who present with photosensitivity. When urine porphyrins are abnormal, characterization of the chromatogram is facilitated by calculation of uroporphyrin-to-heptacarboxylate porphyrin (uro/hepta) and uroporphyrin-to-isocoproporphyrin (uro/iso) ratios. The most frequent abnormal pattern, and that most consistent...

The porphyrin and phorbin biosynthetic activity of etiolated cucumber (Cucumis sativus, L.) cotyledons was compared to that of cotyledonary homogenates. Etiolated cotyledons incubated with delta-aminolevulinic acid accumulate protoporphyrin, coproporphyrin, small amounts of Mg protoporphyrin monoester, and trace amounts of uroporphyrin. They also incorporate 4-(14)C-delta-aminolevulinic acid in...

This paper reviews the effects of lead (Pb), cadmium (Cd), and arsenic (As) on the mitrochondrion with emphasis on alteration of mitochondrial heme biosynthetic pathway. The information was used to examine results of a Pb x Cd x As interaction study which employed urinary porphyrin excretion patterns as one assessment criterion. Data from the study showed that dietary Pb produced increased uri...

Waldenstr6m (1934) reported the natural occurrence inacute porphyria ofauroporphyrinIII, butWatson, Schwartz & Hawkinson (1945) and Prunty (1946) found evidence for the belief that this Waldenstr8m porphyrin was a mixture of a large proportion of uroporphyrin I with a smaller amount of a type III porphyrin. The observations of Watson et al. (1945) also indicated the presence in the urine ofporp...

Ninety two patients with porphyria cutanea tarda (PCT) were examined ophthalmically in a paired case control study. The incidence of pinguecula and of pterygium was 8 and 2 times higher respectively, in PCT patients than in the control group. The photodamage to the conjunctiva is considered to be a result of the photoactivity of uroporphyrin in the tissues.