X-linked sideroblastic anemia

Etiology

• defect in erythrocytic aminolevulinate synthetase
• ineffective erythropoiesis
• severity depends upon residual aminolevulinate synthetase activity

Clinical manifestations

• refractory hemolytic anemia, pallor & weakness in infancy
• hypersplenism
• iron overload & hemosiderosis

Laboratory

• complete blood count
  • decreased hemoglobin
  • decreased MCV
  • decreased MCHC
• peripheral blood smear
  • microcytosis, hypochromic, anisocytosis, poikilocytosis, polychromasia
  • leukocytes & platelets appear normal
• urinalysis: porphyrins & their precursors within normal limits
• feces: porphyrins & their precursors within normal limits
• bone marrow biopsy
  • hypercellular marrow with a left shift
  • megaloblastic erythropoiesis with abnormal maturation
  • sideroblast stained by Prussian-blue
• genetic analysis: PCR

Management

• anemia may respond to pyridoxine supplementation
• supplemental folate might not be a bad idea
• transfusion for patients unresponsive to pyridoxine
• chelation therapy may be necessary for iron overload

More general terms

• sideroblastic anemia
• X-linked disease

Additional terms

• aminolevulinic acid [ALA] synthetase

Patient information

X-linked sideroblastic anemia patient information

Database

• OMIM: https://mirror.omim.org/entry/301300