Congenital Erythropoietic Porphyria. II. The Effects of Induced Polycythemia

Polycythemia and anemia were inducedin a patient with congenital erythropoietic porphyria as a possible means ofaltering erythropoiesis and its attendantporphyrin production. Maintenance ofhematocrits at 50 per cent and 60 percent for periods of 2 weeks decreasedboth erythropoiesis and porphyrin excretion to about one-half of their initiallevels. Conversely with a hematocrit of25, erythropoiesis and porphyrin production were increased to about twice thebasal level. Examination of the marrowshowed fluorescence in all late normoblasts and indicated that the patient hasonly one red cell population. During induced polycythemia, a shift in marrowerythroid population to relatively matureforms, apparently related to delayedenucleation, was accompanied by a retention of the reticulocyte pool andfluorescent cells within the marrow. During anemia, the occurrence of relativelymore immature erythroid cells was accompanied by a shift of the reticulocytepool and fluorescent cells into the circulating blood. During polycythemia, increases were observed in the relativenumber of nuclear vacuoles peculiar tothis disease, in the retention of radioironin the marrow and in the relative amountof stercobilin excretion. In anemia theseparameters decreased towards normal.

Submitted on June 30, 1969 Revised on March 16, 1970 Accepted on April 1, 1970