Osteoporosis in patients with erythropoietic protoporphyria.

Background: Erythropoietic protoporphyria (EPP) is a rare metabolic disease with painful photosensitivity due to protoporphyrin IX accumulation.

Objectives: To evaluate bone mineral density (BMD) and known osteoporosis risk factors in patients with EPP.

Methods: Patients with EPP attending the Erasmus MC outpatient clinic who had undergone BMD measurements were included.

Evidence for an ancestral founder of the common R116W mutation in the hydroxymethylbilane synthase gene in acute intermittent porphyria in The Netherlands.

Introduction: Acute intermittent porphyria (AIP), the most common acute hepatic porphyria, is an autosomal dominant inborn disorder of heme biosynthesis caused by mutations in the porphobilinogen deaminase (PBGd) gene. The prevalence of AIP in Europe is estimated as 1/10.000-1/20.

Porphyrin synthesis by human hepatocytes and HepG2 cells--effects of enzyme inducers and delta-aminolevulinic acid.

Experiments were carried out to investigate the possibility of inducing porphyria in human hepatocytes and HepG2 cells in culture. After treatment with hexachlorobenzene, 3-methylcholanthrene, phenobarbital or dimethyl sulfoxide, protoporphyrin was the predominating porphyrin accumulating in presence of delta-aminolevulinic acid. The typical uroporphyrin accumulation, as is seen in hexachlorobenzene-induced porphyria in vivo, was absent.

Determination of haemoglobin in gastric aspirates.

The haemoglobin content of gastric aspirates can be quantitated by conversion of non-fluorescent haem to fluorescent porphyrins by heating gastric aspirates with oxalic acid and ferrous sulphate. Recovery of haemoglobin added to gastric aspirates was 92 +/- 9%, variation coefficient, n = 52, day to day variation less than 8%. This method was used to calculate blood (haemoglobin) loss in 211 (24 hours) gastric aspirates obtained from 58 intensive care patients.