Sideroblastic Anaemia: Symptoms, Diagnosis, and Treatment (PDF)

Microcytic Hypochromic anaemia (3) Sideroblastic Anaemia Presented by Dr.Sahar Gamal Elbager Assistant Professor of Haematology UMST  Objective By the end of this lecture, the student should be know the: 1. Definition and classification of...

Microcytic Hypochromic anaemia (3) Sideroblastic Anaemia Presented by Dr.Sahar Gamal Elbager Assistant Professor of Haematology UMST  Objective By the end of this lecture, the student should be know the: 1. Definition and classification of Sideroblastic Anaemia 2. Pathophysiology ad Clinical features of Sideroblastic Anaemia 3. Laboratory findings in Sideroblastic Anaemia 4. Differential diagnosis of Sideroblastic Anaemia 02/10/25 Dr.Sahar Gamal Elbager 2  Sideroblastic Anaemia Definition: This is a refractory anaemia with hypochromic cells in the peripheral blood and increased marrow iron; it is defined by the presence of many pathological ring sideroblasts in the bone marrow due to defect in haem synthesis. 02/10/25 Dr.Sahar Gamal Elbager 3  Classification of sideroblastic anaemia 1) Hereditary :Sex- linked occurs in males, rarely in females 2) Acquired a) Primary : Myelodysplasia b) Secondary: 1) Malignant diseases of the marrow (myelofibrosis, leukaemia( 2) Drugs & chemical: antituberculous lead, ethanol 3) Other benign conditions: haemolytic anaemia rheumatoid arthritis) 02/10/25 Dr.Sahar Gamal Elbager 4  Pathophysiology Due to disturbance of the enzymes regulating heme synthesis (in hereditary sex-linked form of S.A is decreased in erythropoietic ALA synthetase ). Ringed sideroblast are formed in accumulation of non ferritin iron in the mitochondria, which circle the normoblast nucleus The mitochondria are eventually rupture as they become laden with iron. when stained with iron stain appears as blue punctuate deposits circulating all parts of the nucleus. 02/10/25 Dr.Sahar Gamal Elbager 5  Heme biosynthesis 02/10/25 Dr.Sahar Gamal Elbager 6  Siderocyte Siderocyte: Are red cells containing granules of non heme iron with a positive Prussian blue reaction. In health individual, siderocyte are not normally found in peripheral blood, but small number are seen following Splenctomy. 02/10/25 Dr.Sahar Gamal Elbager 7  Sideroblast Sideroblast: Are erythroblast with a Prussian blue positive iron granules in their cytoplasm. There are 3 types of sideroblast, one normal and 2 abnormal (classified on the basis on number,size and distribution of the siderotic granules) 02/10/25 Dr.Sahar Gamal Elbager 8  Sideroblast 1. Type 1 Seen in normal B.M and represents iron that has not been utilized for Hb synthesis. Their granules few in number, small, difficult to see and scattered throughout cytoplasm and are not localized in the preinuclear zone About 30-40% of erythroblast normally are sideroblasts. They are not seen in IDA. 02/10/25 Dr.Sahar Gamal Elbager 9  Sideroblast Type 2 This is abnormal and may be found in condition in which the percentage saturation of transferrin is increased such as dyserythropoiesis or hemolysis Their granules large and more and scattered throughout cytoplasm. 02/10/25 Dr.Sahar Gamal Elbager 10  Sideroblast Type 3 This type is found in conditions in which heme synthesis is disturbed such as idiopathic and secondary sideroblastic anaemia Their granules are more large and numerous than type 2 forming complete or partial ring a round the nucleus known as ring sideroblasts. 02/10/25 Dr.Sahar Gamal Elbager 11  Types of sideroblast T1 T3 T1 T3 T2 02/10/25 Dr.Sahar Gamal Elbager 12  Clinical signs and symptoms 1. pallor 2. dizziness 3. fatigue 4. liver disease 5. enlarged liver or spleen 6. Cardiac arrhythmia 7. Renal failure 02/10/25 Dr.Sahar Gamal Elbager 13  Lab. Diagnosis : Complete blood count (CBC) - Hb:low - PCV: low - RBCs: low - Reticulocyte count: low - MCV, MCH and MCHC :may be normal(presence of dimorphic blood picture) - White cell count: normal - Platelets count: normal 02/10/25 Dr.Sahar Gamal Elbager 14  Peripheral blood picture From STD stained blood film: RBCs : anemia is moderate to severe and dimorphic(macrocyte,microcte) with marked anisocytosis and poikilocytosis. Basophilic stippling is marked and target cells are common,NRBCs. Pappenheimer bodies are present (Prussian blue stain ) DLC: normal. Pltls: normal. 02/10/25 Dr.Sahar Gamal Elbager 15  Peripheral blood picture 02/10/25 Dr.Sahar Gamal Elbager 16  Peripheral blood picture 02/10/25 Dr.Sahar Gamal Elbager 17  Bone marrow aspiration Bone marrow shows erythroid hyperplasia with a maturation arrest. Sideroblastic anaemia is diagnosed when excess of 40% of marrow erythroblasts are ring sideroblasts. (Prussian Blue stain ) 02/10/25 Dr.Sahar Gamal Elbager 18  Bone marrow aspiration 02/10/25 Dr.Sahar Gamal Elbager 19  Biochemical test Iron profile : 1. Serum iron: high 2. Serum Ferritin: high 3. % of saturation: high 4. Total iron binding capacity (TIBC): normal or low 02/10/25 Dr.Sahar Gamal Elbager 20  Differential diagnosis 02/10/25 Dr.Sahar Gamal Elbager 21  Diagnostic tests Free erythrocyte protoporphyrin (FEP) Levels are reduced in X-linked sideroblastic anaemia. Molecular studies Mutations common in aminolevulinate synthase (ALAS2) gene 02/10/25 Dr.Sahar Gamal Elbager 22  Treatment The treatment of sideroblastic anaemia varies according to its cause Acquired sideroblastic anaemia should be treated by the removal of the offending agent. Underlying inflammatory conditions, such as rheumatoid arthritis, should be treated Vitamin B6 50–200 mg/day may reverse anaemia Whole red blood cell transfusion may be required in extreme cases of anaemia. 02/10/25 Dr.Sahar Gamal Elbager 23  Prognosis and Complications Iron overload accompanies sideroblastic anaemia – When repeated whole red blood cell transfusion is needed to treat anaemia, it exacerbates existing iron burden – Patients will probably require chelation therapy. In patients with acquired sideroblastic anaemia, leukaemia may develop. 02/10/25 Dr.Sahar Gamal Elbager 24  Lead poisoning Lead inhibits both haem and globins synthesis In addition it interferes with the break down of RNA by inhibiting the enzyme pyrimidine-5-nucleotidase Causing accumulation of denaturised RNA in red cell giving basophilic stippling appearance on Romanowsky stains. The anaemia may be hypochromic or haemolytic the bone marrow may show ring sideroblasts. Free erythrocyte protoporphyrin is raised 02/10/25 Dr.Sahar Gamal Elbager 25  Symptoms Poor appetite Abdominal pain (with or without vomiting). Sleeplessness Headaches Constipation 02/10/25 Dr.Sahar Gamal Elbager 26  Basophilic stippling 02/10/25 Dr.Sahar Gamal Elbager 27  Thank you 02/10/25 Dr.Sahar Gamal Elbager 28