SICKLE CELL DISEASE. Dr. MUBARAK ABDELRAHMAN MD PEDIATRICS AND CHILD HEALTH. Assistant Professor FACULTY OF MEDICINE -JAZAN

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1 SICKLE CELL DISEASE Dr. MUBARAK ABDELRAHMAN MD PEDIATRICS AND CHILD HEALTH Assistant Professor FACULTY OF MEDICINE -JAZAN

2 Objective: The student should be able: To identify the presentation, diagnosis, management and long term complications of Sickle Cell Disorder and Thalassemia.

3 Hemoglobin Synthesis Adult hemoglobin - 96% HgA (a 2 B 2 ) a 2 B2 a 2 B2

4 Hemoglobinopathies Abnormal Hb Structure (Qualitative) Hereditary Disorders >300 Types Abnormal Hemoglobin Hemoglobin S Disorders - Most Prevalent - Sickle Cell Disease - Homozygous (SS) - Sickle Cell Trait - Heterozygous

5 Hemoglobin S Disorders 6th GLU VAL HbA HbS Point Mutation of B Globin Gene Hb S Gene occurs in Africa and middle east.

6 Sickle Cell Disease Sickle cell Deoxygenation (or H 2 0, ph) Ca K, O 2 O 2 Polymerization of Hgb S

7 Sickle Cells

8 Clinical presentation Depends on severity of condition and age of the child. Hand foot syndrome in infants Pallor, jaundice, splenomegaly in young children Pallor, jaundice and no spleen in older children

9 Clinical presentation cont. Sickled cells are hemolyzed in the Spleen (young children- Splenomegaly) Micro vascular occlusion: - Tissue Infarcts and Pain - Auto-splenectomy (older children) - Infections - Salmonella Osteomyelitis

10 COMPLICATIONS Infections Vaso-occlusive effects (Acute chest syndrome) Cholecystitis Renal failure is common Neurological complications Leg ulcers

11 COMPLICATIONS cont. Crisis: Hemolytic Aplastic - Usually Parvovirus Infectious crisis Vaso-occlusive crisis Sequestration crisis

12 Diagnosis Sickling test In vitro sickling after adding Reducing Agent Hb electrophoresis to detect Hb S DNA Analysis - Prenatal Testing

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14 TREATMENT Emergency Department Care: Administer oral hydration if the patient can tolerate oral fluids. Administer IV fluids Medications involved in treatment of sickle cell anemia include analgesics for pain and antibiotics for infections.

15 TREATMENT cont. In/Out Patient Meds: Folic acid. Discharge patient on oral analgesics for a week. Antibiotics when an infection is suspected. Hydroxyurea: Increases hemoglobin F. Hematopoietic stem cell transplantation

16 TREATMENT cont. Simple blood transfusion Aplastic crisis and acute sequestration crisis. Exchange blood transfusion Cerebrovascular accidents (CVA), acute chest syndrome. And occasionally in cases of priapism. ## Exchange transfusion consists of replacing the patient's RBCs by normal donor RBCs, decreasing HbS to less than 30%.

17 TREATMENT cont. Consultations: Ophthalmologist, if retinopathy is suspected and visual symptoms are present. Urologist in case of priapism that does not resolve after 6 hours. Orthopedist, if avascular necrosis of the hip or osteomyelitis is suspected. Surgery.

18 Thalassemia Absent or â Synthesis of Globin Chains (Quantitative) Most Frequent in Mediterranean, African and Asian Populations

19 Thalassemia β - Thalassemia - â β Chain Synthesis (Gene Mutations) α - Thalassemia - â α Chain Synthesis (1-3 of 4 Genes Deleted

20 Chromosome 16 α α α Silent carrier HbH disease α - Thalassemia α α α α α α - thalassemia trait (+/- anemia) (severe anemia) Hydrops fetalis (lethal in utero) Hb Bart

21 β - Thalassemia Minor β β β o β â β chain synthesis β β β + β â β chain synthesis Mild or no anemia

22 β - Thalassemia Major β β Chromosome 11 β β β o β o β + β + No β Chain Synthesis â β Chain Synthesis Severe Anemia

23 Clinical Presentation Anemia, jaundice, splenomegaly, prominent maxillary and frontal bones

24 Diagnosis Peripheral Blood Smear: - Target cells and basophilic stippled RBCs - Severe Hypochromic Microcytic Anaemia ( Hb A MCHC) Bone Marrow: - Erythroid Hyperplasia - Skeletal deformities Extra medullary Hematopoiesis - Splenomegaly and Hepatomegaly

25 Complications Growth Retardation Systemic Iron Overload (due to chronic blood transfusions) = Cirrhosis, Cardiomyopathy (Cardiac Failure), Death (2nd-3rd Decade)

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