BACKGROUND AND OBJECTIVES: The porphyrias are a group of rare, mainly inherited, diseases caused by a deficiency of one of the enzymes of the haem biosynthesis pathway. The biochemical hallmark of an acute attack is an increase in urine porphobilinogen (PBG), together with an increase in urinary excretion of δ-aminolaevulinic acid (ALA) and total urine porphyrins (TUP). In patients with acute intermittent porphyria (AIP) the concentrations of the porphyrin precursors are thought to remain elevated for many years following an acute attack, although this has not been well documented. METHODS: We measured urine ALA, PBG and TUP excretion in 20 patients with AIP following an attack of acute porphyria over a time period of 3 months to 23 years after their last documented acute attack. RESULTS: We showed that urinary concentrations of all metabolites remain elevated for many years. The urinary half life of TUP was 5.3 years, ALA 7.7 years and PBG 10.6 years. Even after 20 years, PBG concentrations remained elevated above the normal range. CONCLUSIONS: Our study highlights the difficulties of using urinary analysis for diagnosing recurrent attacks, and also raises important questions about the pathophysiology of the condition.
BACKGROUND AND OBJECTIVES: The porphyrias are a group of rare, mainly inherited, diseases caused by a deficiency of one of the enzymes of the haem biosynthesis pathway. The biochemical hallmark of an acute attack is an increase in urine porphobilinogen (PBG), together with an increase in urinary excretion of δ-aminolaevulinic acid (ALA) and total urine porphyrins (TUP). In patients with acute intermittent porphyria (AIP) the concentrations of the porphyrin precursors are thought to remain elevated for many years following an acute attack, although this has not been well documented. METHODS: We measured urine ALA, PBG and TUP excretion in 20 patients with AIP following an attack of acute porphyria over a time period of 3 months to 23 years after their last documented acute attack. RESULTS: We showed that urinary concentrations of all metabolites remain elevated for many years. The urinary half life of TUP was 5.3 years, ALA 7.7 years and PBG 10.6 years. Even after 20 years, PBG concentrations remained elevated above the normal range. CONCLUSIONS: Our study highlights the difficulties of using urinary analysis for diagnosing recurrent attacks, and also raises important questions about the pathophysiology of the condition.
Authors: María Barreda-Sánchez; Juan Buendía-Martínez; Guillermo Glover-López; Carmen Carazo-Díaz; María Juliana Ballesta-Martínez; Vanesa López-González; María José Sánchez-Soler; Lidya Rodriguez-Peña; Ana Teresa Serrano-Antón; Remedios Gil-Ferrer; Maria Del Carmen Martínez-Romero; Pablo Carbonell-Meseguer; Encarna Guillén-Navarro Journal: Orphanet J Rare Dis Date: 2019-02-26 Impact factor: 4.123
Authors: Laurent Gouya; Paolo Ventura; Manisha Balwani; D Montgomery Bissell; David C Rees; Ulrich Stölzel; John D Phillips; Raili Kauppinen; Janneke G Langendonk; Robert J Desnick; Jean-Charles Deybach; Herbert L Bonkovsky; Charles Parker; Hetanshi Naik; Michael Badminton; Penelope E Stein; Elisabeth Minder; Jerzy Windyga; Radan Bruha; Maria Domenica Cappellini; Eliane Sardh; Pauline Harper; Sverre Sandberg; Aasne K Aarsand; Janice Andersen; Félix Alegre; Aneta Ivanova; Neila Talbi; Amy Chan; William Querbes; John Ko; Craig Penz; Shangbin Liu; Tim Lin; Amy Simon; Karl E Anderson Journal: Hepatology Date: 2019-11-07 Impact factor: 17.425