Hemoglobinopathies And Sickle Cell Anemia Flashcards
What is sickle cell disease?
Single point mutation
Change from glutamine to valine
Autosomal recessive pattern of inheritance
Homozygous SS is sickle cell anemia
Heterozygous SA is sickle cell trait
Predominantly in african heritage but not exclusively
How to diagnose sickle cell anemia?
Lab tests: reticulocytosis, elevated LDH, decline haptoglobin
HPLC- confirmatory diagnosis
What are some symptoms of sickle cell anemia?
Vaso occlusive crisis
Bone pain
Stroke in 25% by age 45
Thrombosis- leading cause of death
How to treat acute vaso occlusive crisis?
Remove precipitating factors Treat fever and infection aggressively Hydration Oxygen Pain control Transfusion
What is the long term treatment of sickle cell anemia?
PCN prophylaxis due to increased risk of infections ( osteomyelitis caused by salmonella species)
Hydroxyurea to increase HbF
Iron chelation
Transplantation
What is thalassemia?
Inherited syndromes of hemoglobin globin syntheis
Imbalance between alpha and beta chains
Severity depends on the number of completed tetrads
Gene deletion (alpha) worse that production impairment
What are some characteristics of beta thalassemia major?
Splenomegaly Extra medullary hematopoiesis Marrow expansion causing damaged bones Typically fatal by age 30 Nucleated RBCs are frequent Target cells are very common
What are some characteristics of beta thalassemia minor?
Microcytic hypochromic
Few target cells
Few nucleated RBCs
Presentation similar to iron deficiency somjst distinguish
What are some characteristics of alpha thalassemia?
Most common in asians
Severity based on number of allele deleted
4 alleles deleted is deadly in utero: hemoglobin Barts->hydrops fetalis-
What is the treatment of thalassemia?
Based on severity
Minor - no therapy required
Major- chronic transfusion,splenectomy,HCT
