HEMA SYNTHESIS DURING PYRIDOXINE THERAPY IN 2 FAMILIES WITH DIFFERENT TYPES OF HEREDITARY SIDEROBLASTIC ANEMIA

  • 1 January 1982
    • journal article
    • research article
    • Vol. 14  (2) , 61-65
Abstract
The activity of .delta.-aminolevulinic acid synthase (ALA-S) as well as the concentrations of coproporphyrin and protoporphyrin in peripheral red blood cells were examined in 2 sisters and in 2 brothers with hereditary sideroblastic anemias (HSA) of different types. The measurements were done before and during treatment by pyridoxal-5-phosphate (PLP) and/or pyridoxine chloride. Previous family studies indicated an X chromosome-linked HSA in the 2 brothers, whereas the precise mode of inheritance in the 2 sisters was not established. Previous and present studies revealed no characteristic defect in heme synthesis in the 2 sisters, and their treatment by PLP or pyridoxine produced no hematologic response, although a slight stimulation of heme synthesis was observed. The 2 brothers showed decreased activity of ALA-S and decreased protoporphyrin concentration in peripheral red blood cells. After treatment by PLP and/or pyridoxine the ALA-S activity was restored to normal. Corresponding to the stimulation of heme-synthesis a partial hematological response was observed in both brothers. Stopping and restarting of pyridoxine therapy in 1 brother confirmed these results. These observations indicate the presence of 2 genetically and biochemically different types of HSA and explain the varying response to pyridoxine therapy in this rare disorder.