Erythrocyte Uroporphyrinogen DecarboxylaseActivity: Diagnostic Value and RelationshipWith Clinical Features in Hereditary PorphyriaCutanea T arda

• Published in: The American journal of the medical sciences 1998-01, Vol.315 (1), p.59-62
• Main Authors: Camagna, Antonio, Del Duca, Pietro, Petrinelli, Paola, Borelli, Lola G., Ciancio, Loreta, Cipollone, Lorena, Misasi, Gloria, Manfredi, Maria R., Dionisi, Simona, Martinis, Carlo De
• Format: Article
• Language: English
• Subjects: Erythrocyte uroporphyrinogen decarboxylase activity; Familial porphyria cutanea tarda; Hepatoerythropoietic porphyria; Tissue-specific isozymes
• ISSN: 0002-9629; 1538-2990
• DOI: 10.1016/S0002-9629(15)40273-3

A marked discrepancy betweenmild and late clinical features and a nearly completeabsence of erythrocyte uroporphyrinogendecarboxylase activity (Ery-UROD activity) wasobserved in a case of inherited porphyria cutaneatarda. The entity and time of appearanceof clinical features, the onset of clinical symptomsafter exposure to contributing factors, theeffectiveness of phlebotomies and heterozygosityof the mother alone for uroporphyrinogendecarboxylase (UROD) deficiency were typicalfor familial porphyria cutanea tarda (F-PCT),whereas the extremely low UROD activity waspeculiar to hepatoerythropoietic porphyria(HEP). These observations indicate that: 1) EryURODactivity may not always be useful to discriminatebetween F-PCT and HEP; 2) EryURODactivity does not always correlate withclinical symptoms; 3) in inherited UROD deficiency,the genetic defect may be heterogeneous.Finally, the observed discrepancy may provideadditional evidence for the existence of tissuespecificisozymes.