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[Hereditary sideroblastic anemia: a rare diagnosis]
N Brahem-Jmili1, N Salem, S Abdelkefi
1Laboratoire d'hématologie, CHU Farhat Hached, Sousse, Tunisia. jmilinejia@yahoo.fr
Annales De Biologie Clinique
|June 26, 2004
Summary
This case study highlights a rare hereditary sideroblastic anemia in an infant. Pyridoxine treatment showed moderate improvement, emphasizing the need to explore diverse causes of microcytic anemia.
Area of Science:
- Hematology
- Genetics
- Pediatrics
Background:
- Hereditary sideroblastic anemia (HS A) is a rare genetic disorder affecting heme biosynthesis due to reduced delta-aminolevulinic acid synthase (ALAS) activity.
- It can be inherited in autosomal recessive or X-linked patterns.
- This condition leads to ineffective erythropoiesis and iron overload.
Observation:
- A six-month-old boy presented with severe anemia (hemoglobin 4.5 g/dL), characterized by hypochromic microcytic red blood cells and high reticulocyte count.
- Bone marrow examination revealed erythroid hyperplasia with significant dyserythropoiesis and ringed sideroblasts (90%), indicating iron accumulation within mitochondria.
- Genetic analysis of ALAS2 and ABC7 genes did not reveal abnormalities.
Findings:
- Despite the absence of identified genetic mutations in ALAS2 and ABC7, the clinical and morphological findings strongly suggest a form of hereditary sideroblastic anemia.
- Pyridoxine therapy resulted in a moderate correction of the anemia, indicating a partial response to the cofactor.
Implications:
- This case underscores the importance of considering HS A in infants with unexplained microcytic anemia, even when common genetic mutations are not detected.
- It highlights the diagnostic challenge in differentiating HS A from other microcytic anemias like iron deficiency, anemia of inflammation, and thalassemia.
- Further investigation into novel genetic or regulatory mechanisms underlying HS A may be warranted.
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