32 Sideroblastic Anemia
Michelle To and Valentin Villatoro
Cause(s): Development of sideroblastic anemia can be due to hereditary or acquired causes that lead to abnormal heme synthesis.1,2
Hereditary: Sex-linked or autosomal recessive mutations
Acquired: Idiopathic, MDS and other malignancies, drugs, lead toxicity
Laboratory Features of Sideroblastic Anemia:1-3
MCV, MCH, MCHC: Normal to Decreased (as they are averages of the RBC appearance)
Dimorphic population (Normochromic/Normocytic alongside Hypochromic/Microcytic )
M:E Ratio: Decreased
Erythroid hyperplasia (ineffective erythropoiesis)
Macrophages have increased iron (Increased iron stores)
Serum Iron: Increased
Transferrin: Normal to Decreased
Transferrin Saturation: Increased
TIBC: Normal to Decreased
Prussian blue stain of BM shows increased iron levels and ringed sideroblasts
1. McKenzie SB. Anemias of disordered iron metabolism and heme synthesis. In: Clinical laboratory hematology. 3rd ed. New Jersey: Pearson; 2015. p. 198-230.
2. Doig K. Disorders of iron kinetics and heme metabolism. In: Rodak’s hematology clinical applications and principles. 5th ed. St. Louis, Missouri: Saunders; 2015. p. 297-313.
3. Finnegan K. Iron metabolism and hypochromic anemias. In: Clinical hematology and fundamentals of hemostasis. 5th ed. Philadelphia: F.A. Davis Company; 2009. p. 117-37.