sideroblastic anemia

[Anonymous]

Sideroblastic anemia is an enzyme disorder in which the body has adequate iron but is unable to incorporate it into hemoglobin. Iron enters the developing red blood cell (erythroblasts); here iron accumulates in the mitochondria giving a ringed appearance to the nucleus (ringed sideroblast). The mitochondria are overloaded with iron and hemoglobin production (heme synthesis) is defective. Sideroblasts are visible with Prussian blue staining and observable under microscopic examination of bone marrow. Because these ringed sideroblasts can develop poorly or not at all into mature red cells, anemia is the consequence.
Sideroblastic anemia (SA) is a complicated disorder and therefore difficult to treat. . Often SA acts like iron deficiency anemia (IDA), but unlike IDA, iron tests are normal or increased with SA.
Three categories of sideroblastic anemia are: hereditary, acquired or idiopathic.
Hereditary Sideroblastic Anemia is due to a genetic defect; the gene is an X-linked recessive (not dominant) gene. It may manifest in both men and women but is seen more commonly in young males, maternal uncles and cousins. Hereditary sideroblastic anemia generally manifests during the first three decades of life especially during adolescence but it has been diagnosed in patients over seventy.
Acquired sideroblastic anemia is due to prolonged exposure to toxins like alcohol, lead, drugs or nutritional imbalances such as deficiency in folic acid, deficiency in copper or excess zinc. Other causes are due to disease such as inflammatory conditions like rheumatoid arthritis, cancerous conditions such as leukemia, lymphoma; kidney disorders causing uremia; endocrine disorders such as hyperthyroidism; metabolic disorders such as porphyria cutanea tarda. Acquired SA is usually seen in patients over 65 year of age but it can be present as early as mid to late fifties.
Idiopathic means the cause is unknown; this category of SA is referred to as myelodysplastic syndrome (MDS). Myelodysplasia is a bone marrow dysfunction disorder which can develop into aplastic anemia requiring bone marrow or stem cell transplantation. Lab findings for acquired/idiopathic sideroblastic anemia: Anemia is usually mild with hemoglobin 10-11.8g/dL Serum iron increased, transferrin iron saturation percentage increased, ferritin increased, transferrin is decreased. TIBC is normal to decreased; serum transferrin receptor is normal to high Mean Corpuscular Volume (MCV) is normal to slightly increased. Mean Corpuscular Hemoglobin (MCH) and Mean Corpuscular Hemoglobin Concentration (MCHC) are usually normal. Red Cell Distribution Width (RDW) is increased. White blood cells and platelets are decreased.
Symptoms might include enlarged spleen or liver, liver disease, cardiac arrhythmia along with the following specific lab findings:
Hemoglobin will generally be less than 10.0g/dL
Hypochromic (reduced color) cells coexisting with normal cells
Serum iron increased
transferrin iron saturation percentage increased
ferritin increased
transferrin decreased
total iron binding capacity (TIBC) is normal to decreased
serum transferrin receptor is normal to high
Stainable marrow and hemosiderin is increased
Ringed sideroblasts present
Red Cell Distribution Width (RDW) is increased
White blood Cells and platelets are normal.