Hematologic disorders Flashcards
What is erythropoiesis stimulated by?
Human RBC production (erythropoiesis) is stimulated by erythropoietin in the kidney
Where are RBCs produced?
Continuously produced in red bone marrow by committed stem cells
How long does it take for RBC formation to maturity
~7 days
How long is the lifespan of RBC?
120 days
Rate of RBC production
2 million cells/sec
What is the reticuloendothelial system (RES)?
- Spleen, liver, bone marrow
- Responsible for removing old or defective RBCs
What happens to the plasma membrane as RBC ages?
Plasma membrane undergoes changes increasing susceptibility to phagocytosis (eryptosis)
What is the rate of eryptosis equivalent to?
Rate of eryptosis = rate of erythropoiesis
Disorders of increased eryptosis
- Sepsis
- Malaria
- Sickle cell anemia
- Beta thalassemia
- Glucose-6-phosphate dehydrogenase deficiency
- Iron deficiency
- Wilson disease
What is anemia?
Anemia is reduction of RBC volume, hemoglobin concentration below range or values that occur in healthy person (12-18g/100mL)
Acquired hypoproliferative anemia
- Nutritional deficiency (iron, folate, vitamin B12 deficiency)
- Acquired aplastic (pancytopenia)
- Transient erythroblastopenia (may have viral cause)
- Anemia of acute inflammation
- Marrow replacement by malignancy (ex: leukemia)
- Effects of drugs or toxins (ex: lead poisoning)
Congenital hypoproliferative anemia
- Diamond Blackfan syndrome
- Refractory sideroblastic anemia
Congenital hemolytic anemia
- Inherited disorders of hemoglobin
- Hemoglobinopathies (sickle cell disease, alpha and beta thalassemia)
- Enzymopathies (ex: G6PD deficiency)
- RBC membrane disorder (hereditary spherocytosis)
Acquired hemolytic anemia
- Autoimmune hemolysis – body makes antibodies against own RBCs
- Autoimmune disorders
- Systemic lupus (SLE) rheumatoid arthritis, ulcerative colitis
- Hemolysis related to infection
- (CMV, Epstein Barr Virus, hepatitis) Rh/ABO incompatibilities
What possible hematological abnormality may be associated w/ oral ulcers?
Neutropenia
What possible hematological abnormality may be associated w/ glossitis?
- Megaloblastic anemia
- Iron deficiency anemia
What possible hematological abnormality may be associated w/ angular stomatitis?
Iron deficiency anemia
What possible hematological abnormality may be associated w/ candida?
Immunosuppression
What possible hematological abnormality may be associated w/ skin pallor?
Any anemia
What possible hematological abnormality may be associated w/ jaundice?
Hemolytic anemia
What possible hematological abnormality may be associated w/ excessive bruising?
- Coagulation disorder
- Thrombocytopenia
What possible hematological abnormality may be associated w/ purpuric/petechial rash?
Thrombocytopenia