Anemia Flashcards
What is the physiological definition of anemia?
Hemoglobin level too low to meet cellular oxygen demands.
What factors determine hemoglobin values?
Age, gender, race, degree of sexual maturation, altitude, heredity.
What do RBC indices describe?
Size, shape, hemoglobin content of RBCs, and uniformity of RBC population.
What does a low Mean Corpuscular Hemoglobin (MCH) indicate?
Hypochromia.
What does a high Red Cell Distribution Width (RDW) signify?
Underlying condition, such as anemia, autoimmune conditions, and liver or kidney disease.
What are the pathophysiologic mechanisms of anemia?
Decreased production, acute blood loss, increased destruction (hemolysis).
What are the types of anemia based on erythrocyte size?
Microcytic, normocytic, macrocytic.
What are the causes of microcytic anemia?
Iron deficiency, sideroblastic, thalassemia, anemia of chronic disease.
What are the causes of macrocytic anemia?
B12, folate deficiency.
What are the causes of normocytic anemia?
Chronic disease, aplastic.
What are the types of increased RBC destruction?
Hemolysis (acquired or congenital).
What are the protective mechanisms against too much iron?
Highly regulated iron absorption, iron tightly bound to proteins.
What are the symptoms of iron deficiency anemia?
Weakness, fatigue, SOB, pallor, dizziness, irritability, decreased exercise tolerance, pica.
What is the most specific and reliable indicator of iron deficiency?
Ferritin levels
How should iron studies be interpreted?
In combination with RBC indices, peripheral smear, and history
What are the lab indicators of iron deficiency anemia?
High TIBC, low serum iron, low transferrin saturation, low ferritin.
What is the primary treatment for iron deficiency anemia?
Oral iron therapy
What are common side effects of oral iron therapy?
Nausea, constipation, diarrhea
What is a characteristic feature of sideroblastic anemia?
Iron retained in mitochondria
What is the function of Vitamin B12?
Methionine synthesis and formation of succinyl coenzyme A
What results from folate or Vitamin B12 deficiency?
Megaloblastic anemia
What are clinical findings of Vitamin B12 deficiency?
Neurological abnormalities
What lab findings are associated with folate and Vitamin B12 deficiency?
Macrocytosis, Howell-Jolly bodies, hypersegmentation of neutrophils
What are common causes of folic acid deficiency?
Decreased intake, excessive alcohol consumption, intestinal malabsorption
What is the treatment for Vitamin B12 deficiency?
Daily oral supplement or monthly IM injection
What induces the production of hepcidin in anemia of chronic disease?
Inflammatory cytokines
What is the hallmark of aplastic anemia?
Hypocellularity and hypoplasia of all cell lines in bone marrow
What is the most common cause of acquired aplastic anemia?
Autoimmune T cell-mediated destruction
What is the most common cause of acquired aplastic anemia?
T cell mediated autoimmune response
What are the primary symptoms of thrombocytopenia?
Easy bleeding/bruising and epistaxis
What diagnostic test is required for confirming aplastic anemia?
Bone marrow biopsy and aspirate
What is a highly effective treatment for autoimmune aplastic anemia?
Immunotherapy
What is the most common cause of death in aplastic anemia?
Infection
What characterizes hemolytic anemia?
Increased destruction of erythrocytes
What are the two main types of hemolysis?
Intravascular and extravascular
What is the most common cause of non-immune hemolytic anemia?
Hereditary spherocytosis
What is the primary treatment consideration for hereditary spherocytosis?
Splenectomy, weighing risk/benefit.
What lab marker is elevated due to non-specific cell damage in hemolytic anemia?
LDH
What does a positive direct Coombs test indicate?
Immune etiology
What is the clinical presentation of Thalassemia Minor?
Clinically normal with mild microcytic anemia, usually asymptomatic.
What characterizes Hemoglobin H disease?
Presence of hemolysis, jaundice, and splenomegaly.
What is the outcome of Hydrops Fetalis?
Incompatible with life due to no alpha chains.
What is the most common cause of α-Thalassemia?
Point mutations leading to reduced or absent β-chain synthesis.
What are the complications of untreated β-Thalassemia Major?
Severe anemia, bony deformities, iron overload, and early death from cardiac failure.
How is β-Thalassemia Intermedia different from β-Thalassemia Major?
Less severe anemia, diagnosed later, and survival into adulthood.
What is the clinical significance of β-Thalassemia Minor?
Asymptomatic carriers with mild microcytic anemia and normal life expectancy.
What are the treatment options for Thalassemias?
Genetic counseling, supportive care, transfusions, iron chelation, stem cell transplant, and gene therapy.
What genetic mutation causes Hemoglobin S?
Mutation in the β-globin gene leading to polymerization of Hgb-S.
What are the chronic complications of Sickle Cell Disease?
Chronic hemolytic anemia, jaundice, organ damage, and increased risk of infections.
What is a common neurological event in sickle cell disease that can be clinically apparent?
Stroke
What triggers Vaso-occlusive Pain Crisis in Sickle Cell Disease?
Often unknown, but can include skin cooling, infection, stress, and dehydration.
What is the significance of Acute Chest Syndrome in Sickle Cell Disease?
Frequent cause of death and second most common reason for hospitalization.
What are some common symptoms of a stroke in sickle cell disease?
Hemiparesis, aphasia, dysphagia, seizures, headache, cranial nerve palsy, stupor, coma
How is Acute Chest Syndrome managed?
Empiric antibiotics, transfusion, supportive care, and bronchodilators.
What imaging techniques are used for diagnosing a stroke in sickle cell patients?
MRI, MRA, CT without contrast
What is the primary treatment for stroke in sickle cell disease?
Transfusion
What screening tool is used for stroke risk in sickle cell disease?
Transcranial Doppler Ultrasound
What are the key components of managing sickle cell disease?
Early identification, family education, preventive measures, screening, prophylactic penicillin, immunization, treatment of acute complications, disease-modifying agents, chronic transfusion, hydroxyurea, stem cell transplantation, gene therapy
When is transfusion indicated in sickle cell disease?
Acute stroke or TIA, acute chest syndrome, priapism, splenic sequestration, pre-operative, symptomatic anemia, aplastic crisis, abnormal transcranial doppler
When is transfusion not indicated in sickle cell disease?
Pain crisis, anemia
