Asymptomatic erythrocyte disorder presenting as increased porphobilinogen deaminase and uroporphyrinogen decarboxylase

Hematocrit,% Reticulocytes, % Erythrocyte porphobilinogen deaminase and uroporphyrinogen decarboxylase were measured as previously described (5, 6) by using porphobilinogen and pentacarboxylporphyrinogen I, respectively, as substrates. CV5 for these assays in this laboratory are 8.3% and 14.2%, respectively. rocytes,it is possible that detection of these diseases could be compromised when coexisting conditions or interventions stimulate erythropoiesis. It will be of interest, for example, to determine if erythrocyte uroporphyrinogen decarboxylase increases during therapeutic phlebotomy in patients with porphyria cutanea tarda. The intent of this therapy, which is effective in both inherited and acquired forms of porphyria cutanea tarda, is to stimulate erythropoiesis and thereby utilize and reduce iron stores. If phlebotomy does increase erythrocyte uroporphyrinogen decarboxylase, it might be recommended that the enzyme activity be measured before institution of phlebotomy.