RBC intro (AI made) Flashcards
What does the term ‘anemia’ derive from?
‘Anemia’ was derived from the Greek word anaimia, meaning ‘without blood’
It refers to a condition characterized by a decrease in hemoglobin concentration or the number of red blood cells (RBCs), leading to reduced oxygen delivery to tissues.
How is anemia operationally defined?
Anemia is defined as the reduction in hemoglobin content of the blood caused by a decrease in RBC count, hemoglobin concentration, and hematocrit below the reference interval for healthy individuals
It is not considered a disease but a manifestation of an underlying condition.
What are the two types of anemia based on RBC mass?
- Relative Anemia
- Absolute Anemia
What characterizes relative anemia?
RBC mass is normal, but there is increased plasma volume
This can occur due to conditions like pregnancy or volume overload.
What characterizes absolute anemia?
RBC mass is decreased, and plasma volume is normal
This indicates a true decrease in erythrocytes and hemoglobin.
What are some common clinical findings in patients with anemia?
- Fatigue
- Shortness of Breath
- Pallor
- Jaundice
- Sternal tenderness
- Lymphadenopathy
- Cardiac murmurs or arrhythmias
- Splenomegaly
- Hepatomegaly
What are the classical symptoms of moderate anemia?
Hgb 7-10 g/dL — pallor of conjunctivae and nail beds, dyspnea, vertigo, headache, muscle weakness, lethargy
What are the symptoms of severe anemia?
Hgb <7 g/dL — symptoms of moderate anemia + tachycardia, hypotension, and other symptoms of volume loss
What is the physiological response to acute blood loss?
- Increase in heart rate
- Increase in respiratory rate
- Increase in cardiac output
- Redistribution of blood flow from skin to essential organs
What is ineffective erythropoiesis?
Defective production of erythroid precursor cells which often undergo apoptosis in the bone marrow before maturing
This can lead to conditions such as megaloblastic anemia and thalassemia.
What are the causes of insufficient erythropoiesis?
- Iron deficiency
- EPO deficiency
- Loss of erythroid precursors
- Infiltration of bone marrow by leukemic cells or non-hematopoietic cells
What characterizes acute blood loss?
Sudden loss of blood resulting from trauma or other severe forms of injury
What are intrinsic defects in hemolysis?
Defects in the RBC membrane, enzyme systems, and hemoglobin
What are extrinsic defects in hemolysis?
May be due to immune (antibody-mediated) or non-immune (mechanical fragmentation or infection-related destruction) causes
What is included in a complete blood count (CBC)?
- RBC count
- Hemoglobin (Hgb)
- Hematocrit (Hct)
- RBC indices (MCV, MCH, MCHC, RDW)
- WBC count
- Platelet count
What does reticulocyte count assess?
The bone marrow’s ability to increase RBC production in response to anemia
What is the purpose of a peripheral blood film examination?
To assess RBC diameter, shape, color, amount of hemoglobin, and inclusions
What findings in bone marrow can point to the underlying cause of anemia?
- Abnormal cellularity
- Evidence of ineffective erythropoiesis
- Lack of iron on iron stains
- Presence of granulomata, fibrosis, infectious agents, and tumor cells
What are the laboratory findings in iron deficiency anemia?
- Decreased: Hgb, Hct, MCV, MCH, MCHC
- Increased: RPI, Reticulocyte Count
- Other findings: TIBC, FEP, RDW, Microcytic Hypochromic RBCs
What characterizes microcytic anemias?
An MCV of <80 fL with small RBCs (<6 um)
Often associated with hypochromia.
What are the causes of iron deficiency anemia?
- Inadequate intake
- Increased demand for iron
- Impaired absorption
- Chronic blood loss
What are the stages of iron deficiency anemia?
- Stage 1: Loss of storage iron
- Stage 2: Exhaustion of iron storage pool
- Stage 3: Frank anemia with low Hgb and Hct
What are the clinical findings associated with iron deficiency anemia?
- Fatigue
- Weakness
- Shortness of breath
- Pallor
- Sore tongue
- Cracks at the corners of the mouth
- Koilonychias
- Pica syndrome
What is anemia of chronic disease/inflammation characterized by?
Inability to use available iron for hemoglobin production
It is commonly seen in infections, inflammatory diseases, or malignant diseases.
What is the role of hepcidin during inflammation?
Increases synthesis during inflammation, leading to decreased iron absorption and release from macrophages and hepatocytes
What are the lab findings in anemia of chronic inflammation?
- Decreased: Hgb, Hct, Serum Iron, TIBC
- Increased: FEP, Serum Ferritin
- Other findings: Microcytic Hypochromic RBCs
What is the most significant cause of anemia?
Ferrokinetics
Ferrokinetics refers to the dynamics of iron metabolism in the body, which plays a crucial role in the production of hemoglobin.
What are the lab findings in anemia of chronic inflammation?
Decreased: Hgb, Hct, Serum Iron, TIBC
Increased: FEP, Serum Ferritin
Other Findings: Microcytic Hypochromic RBCs, Stored Iron in Macrophages
RPI: <2.0
TIBC stands for Total Iron Binding Capacity, and FEP stands for Free Erythrocyte Protoporphyrin.
What characterizes sideroblastic anemia?
Blocks in the protoporphyrin pathway leading to defective Hgb synthesis and iron overload
Sideroblastic anemia is associated with excess iron accumulation in erythrocytes and is identified by the presence of siderocytes.
What inclusions are seen in sideroblastic anemia?
Basophilic Stipplings, Ringed Sideroblasts, Pappenheimer Bodies
These inclusions can be identified using specific staining methods, such as Pearl’s Prussian Blue Stain.
What are the clinical signs of lead poisoning?
Abdominal pain, muscle weakness, gum lead line
The gum lead line is characterized by blue/black deposits of lead sulfate.
What laboratory findings are associated with lead and arsenic poisoning?
Decreased: Hgb, Hct
Increased: FEP, Transferrin Saturation
Other Findings: Microcytic Hypochromic RBCs, Normal serum ferritin
Basophilic stipplings may also be noted in cases of pyrimidine-5’-nucleotidase deficiency.
What are porphyrias?
Diseases characterized by impaired production of the porphyrin component of heme
Porphyrias can be acquired (e.g., lead poisoning) or hereditary.
What is the inheritance pattern of Acute Intermittent Porphyria (AIP)?
Autosomal Dominant
AIP is the most common acute porphyria and is characterized by increased urine ALA and PBG.
What is a key feature of Beta-Thalassemia Major?
Severe hemolytic anemia requiring regular transfusion therapy
This condition is usually diagnosed between 6 months and 2 years of age.
What laboratory findings are typical in Beta-Thalassemia Major?
Severely Microcytic Hypochromic RBCs, Decreased Hgb concentration, Increased RDW and TIBC
Peripheral blood film shows various abnormalities including target cells and Heinz bodies.
What is the primary cause of alpha-thalassemia?
Deletions that remove one or both alpha-globulin genes
This condition affects chromosome 16 and leads to reduced synthesis of alpha globin chains.
What is the genotype for Alpha Thalassemia Silent Carrier?
- a / a a
This indicates one alpha gene deletion with no clinical manifestations.
What are the clinical findings associated with Congenital Erythropoietic Porphyria (CEP)?
Red pigmented urine, hemolytic anemia, severe cutaneous photosensitivity
Patients often show symptoms early in childhood.
Fill in the blank: The excess porphyrins from porphyrias may be excreted in _______.
urine or feces
This can allow for the diagnosis of the condition, often seen with port wine color of urine.
False or True: Siderocytes are best demonstrated using Pearl’s Prussian Blue Stain.
True
This specific staining method highlights iron deposits in the cells.
What does homozygous refer to in genetics?
Homozygous ( - a / - a) indicates two identical alleles for a gene
What does heterozygous refer to in genetics?
Heterozygous ( - - / a a) indicates two different alleles for a gene
What are the characteristics of asymptomatic alpha thalassemia?
May be characterized by mild microcytic anemia with high RBC count and target cells
What is the significance of Hgb Bart’s in newborns?
Up to 6% Hgb Bart’s (y4) in newborns may be helpful in the diagnosis; absent by 3 months of age
What is Hgb H disease?
A form of alpha thalassemia intermedia characterized by three alpha gene deletions
Where is Hgb H disease common?
Common in Southeast Asia
What is the composition of hemoglobin in newborns with Hgb H disease?
Hgb Bart comprises 10-40% of hemoglobin, with the remainder being Hgb F and Hgb A
What are laboratory findings in Hgb H disease?
Mild to moderate chronic hemolytic anemia, Hgb concentration at 7-10 g/dL, reticulocyte count at 3-10%
What blood smear findings are associated with Hgb H disease?
Microcytic hypochromic RBCs, marked poikilocytosis, target cells, bizarre cells, Hgb H inclusions (stained by supravital stains)
What is alpha thalassemia major also known as?
Hydrops fetalis
What happens in alpha thalassemia major?
All four alpha genes are deleted, resulting in no normal hemoglobins produced
What is the outcome of alpha thalassemia major without treatment?
Results in death in utero or shortly after birth
What is the predominant hemoglobin in fetuses with alpha thalassemia major?
Hgb Bart’s is the predominant hemoglobin
What are common findings in fetuses with alpha thalassemia major?
Anemia, edema, ascites, gross hepatosplenomegaly, and cardiomegaly
In iron deficiency anemia, what are the serum ferritin levels?
Decreased
In iron deficiency anemia, what is the transferrin saturation?
Decreased
What are the laboratory findings for thalassemia?
Increased/Normal Serum Ferritin, Serum Iron; Normal Transferrin Saturation
What are the iron studies findings in anemia of chronic disease?
Decreased Serum Iron, TIBC, Transferrin Saturation; Increased Serum Ferritin
What are the findings in sideroblastic anemia?
Decreased Hgb, Hct, TIBC; Increased Serum Iron, Serum Ferritin
What are the inclusions seen in sideroblastic anemia?
Basophilic stipplings, ringed sideroblasts, Pappenheimer bodies
What are the common findings in lead poisoning?
Normal serum ferritin, serum iron, TIBC; Microcytic hypochromic RBCs
What is the significance of the RDW in microcytic anemias?
Increased in iron deficiency anemia; normal in thalassemia
Fill in the blank: In iron deficiency anemia, the _______ is increased.
TIBC
True or False: In thalassemia, serum iron levels are decreased.
False
