Beta Thalassemia.pptx an overview by DR Khansa

BETA Thalassemia:
Case presentation
Pathophysiology
Inheritance pattern
Types of beta thalassemia
Newer classification of beta thalassemia
Types of Hb
Beta thalassemia minor
Beta thalassemia major
Clinical findings
Complications
Diagnosis
Prenatal diagnosis
Management
Prognosis
Prevention

1. Beta Thalassemia By DR khansa

2. content Case Pathophysiology Inheritance pattern Types of beta thalassemia Newer classification of beta thalassemia Types of Hb Beta thalassemia minor Beta thalassemia major Clinical findings Complications Diagnosis Prenatal diagnosis Management Prognosis prevention inheritance

3. case A 2 year old boy presents with pallor and prominent cheeks . Parents are cousins . On clinical examination , he has mild jaundice ,growth retardation, hepatosplenomegaly . Hb is 5.2g/dl , MCV 65 fl and HbF 35%. A 9 year old girl has greenish brown complexion , maxillary hyperplasia , splenomegaly , and gallstones. Her Hb is 5g/dl and MCV is 65ml.

4. Thalassemia facies

5. Pathophysiology There is decrease in synthesis of beta globin chains There are two genes which code for beta chains One of each copy of gene is present on chromosome 11 It is caused by mutations . Wide spectrum of disease depends on mutation.

6. Pathogenesis

7. Inheritance pattern It is an autosomal recessive disorder. in heterozygous parents, 1 in 4 normal (25%) , 2 in 4 are likely to have thalassemia minor (50%) , 1 in 4 likely to have thalassemia major (25%)

8. Types of beta thalassemia

9. Beta thalassemia has wide spectrum depends on severity of mutation

10. New classification of beta thalassemia

11. Types of Hemoglobin There are many types of Hemoglobin . But in Beta thalassemia 3 types are under consideration: Hb A (α2 ß2) Hb A2 ( α2δ2 ) Hb F (α2γ2)

12. Beta thalassemia minor Also called as Beta thalassemia trait. In this condition ß globin synthesis is reduced. Alpha chain production is normal. The excess alpha chains stimulates increased production of delta chains leading to increased amount of Hb A2. It is an asymptomatic condition. It is the most common form of thalassemia.

13. Beta thalassemia major Also called as transfusion dependent thalassemia Also called as Cooley anemia ( when no beta chains are present) In this condition , beta globin chain synthesis is severely reduced or totally absent. Anemia begins at 1 st year of life (usually 6 th months of age) when HbF levels wanes from the body.

14. Clinical findings Beta thalassemia minor : normal growth and development of patient. Mild anemia (10g/dl) Beta thalassemia intermedia : patients are symptomatic at 2 years of age. Moderate anemia . Beta thalassemia major : patient symptomatic at 12 th months as early as 3months . Severe anemia , icteric tinge, massive hepatosplenomegaly, mandibular prominences, decreased nasal bridge, frontal bossing. Iron overload.

15. complications

16. complications Beta thalassemia intermedia : hepatosplenomegaly , jaundice , growth failure , thalassemia facies Beta thalassemia major : recurrent infections , septicemia , failure to thrive , growth retardation. Iron overload :lead to hepatic fibrosis and cirrhosis , Darkening of skin.

17. comlications Hypercoagulopathy (PE, DVT, cereberal ischemia) Alloimmune and autoimmunization ( hemolytic transfusion reactions) Endocrinopathies( DM , hypothyroidism) Sideroblastic cardiomyopathy(arrhythmias, CCF , recurrent pericarditis). Bone disease: osteopenia, osteoporosis .

18. Diagnosis CBC : in beta thalassemia major Hb 5 to 6 g/dl Retics: increased 5 to 10% Hemoglobin electrophoresis : it is diagnostic test. Minor: dec HbA1,elevated HbA2( upto10%), elevated HbF ( upto 7%) Intermedia: : dec HbA1,elevated HbA2, elevated HbF 60 to 80 % of total Hb Major: absent HbA1,elevated HbA2( >3%).

19. diagnosis Serum iron and TIBC: elevated Serum bilirubin: normal FEP MCV RDW Imaging: Xray Hair on end pattern on skull, thining of bone cortices RBC morphology: microcytic hypochromic anemia , anisocytosis , target cells , nucleated RBCs , Heinz bodies.

20. Hair on end pattern /crew cut appearance of skull

21. Antenatal diagnosis Chorionic villous sampling (in 1 st trimester) Amniocentesis (in 2 nd trimester) Fetal DNA analysis ( 10 th week of gestation)

22. management Goal: maintain hemoglobin levels and prevention of iron accumulation and promotion of iron excretion . Transfusion therapy:packed RBCs transfusion Chelation therapy : deferoxamine S/C , deferasirox oral , deferipone oral. Vitamin C : to increase iron excretion Folic acid : daily Splenectomy: done after 5 years of age , prophylactic pencillin to prevent fulminant sepsis. Bone marrow transplant: from HLA compatible siblings

23. management Gene therapy Hydroxyuyrea : to promote fetal Hb production Recombinant erythropoietin.

24. prognosis Depends on cardiac and liver iron load Death occurs due to congestive heart failure Quality of life improved by blood transfusion and chelation Bone marrow transplant is curative .

25. prevention Genetic counselling

26. Thank you by DR KHANSA