IDA Flashcards
results from the inability of the body to produce sufficient red blood cells (RBCs) due to a lack of essential raw materials for hemoglobin assembly.
Anemia of impaired production
The primary limiting factor in this process is iron, which is essential for forming hemoglobin.
What type of anemia
Iron-Restricted Anemias
2 iron restricted anemia:
- Iron deficiency anemia
- Anemia of chronic inflammation.
occur when the body lacks enough available iron to support hemoglobin synthesis.
Iron-restricted anemias
is due to inadequate production of protoporphyrin, a critical component of heme.
Sideroblastic anemia
Without sufficient protoporphyrin, heme synthesis is disrupted, leading to diminished hemoglobin production.
Iron accumulates in the mitochondria of developing RBCs, forming ringed … visible in the bone marrow.
Sideroblastic anemia
The body has a relative excess of iron, but it cannot be properly incorporated into hemoglobin.
Sideroblastic anemia
Blockages in protoporphyrin production lead to the accumulation of porphyrins or their precursors in the body.
Impaired heme synthesis due to porphyrin accumulation results in defective hemoglobin production.
Porphyrias
• Blockage of protoporphyrin production in heme synthesis => accumulation of of porphyrins
• Accompanied by anemia
Porphyrias
Disorders characterized by abnormal iron metabolism, leading to excessive iron absorption and deposition in organs.
Hemochromatoses
• perturbed iron metabolism
• Excess accumulation of Iron with out anemia
• Hemochromatoses
Cause: Impaired iron kinetics due to defects in iron storage or mobilization.
Effect: Despite having excessive iron stores, the iron is not utilized effectively for RBC production, leading to anemia.
Iron-Loading Anemias
Iron-restricted anemia, particularly iron deficiency anemia (IDA), arises from several mechanisms:
Inadequate Iron Intake
Increased Iron Demand
Impaired Iron Absorption
Chronic Blood Loss
Approximately______ of iron is lost daily through processes like skin shedding and small amounts of blood loss
1 mg
T or F
Body tenaciously conserves all other iron from senescent cell and diet
• Supply the body’s need for RBC production
True
• Dietary insufficiency: If the diet does not consistently replenish this iron, the body’s________ is gradually depleted.
• Effect on RBC production: With inadequate iron, RBC production_____ as the body prioritizes iron use for other essential cells, leading to anemia.
stored iron
slows
______ of cells dying naturally each day => ANEMA
• The production rate is insufficient to replace the lost cells
1%
Inadequate intake
Increased Need Relative to Iron Supply
• Rapid growth phases (e.g.,3),______ and ______ increase iron requirements due to an expanding blood volume.
infancy, childhood, adolescence
pregnancy, and nursing
Increased Need Relative to Iron Supply
Functional iron deficiency can occur during treatment with______, which rapidly stimulates RBC production, leading to an increased demand for iron that the body may fail to meet.
erythropoietin (EPO)
• Treatment with erythropoietin => rapid expansion of erythron
• The DEMAND is increased
• Individuals with adequate stores of iron =>_________
• Cannot be mobilized fast enough =________
IRON-RESTRICTED erythropoiesis
FUNCTIONAL IRON DEFICIENCY
Impaired Iron Absorption
• Malabsorption: Conditions like ________ damage the intestinal lining, reducing iron absorption.
• Inherited mutations: For example, mutations in the _______cause excessive production of hepcidin, a hormone that blocks iron release from storage sites.
celiac disease
matriptase-2 protein
IMPAIRED ABSORPTION
• Inability to absorb that iron through the enterocyte into the blood =>_____
• Malabsorption caused by_____
• INHERITED MUTATION OF IRON REGULATORY PROTEIN
1. Mutation of Matriptase-2 protein = persistent production of______
•_______ (aging)
• __________surgeries
•________ (stomach acid reducers)
• Some bind to iron preventing the absorption
IDA
CELIAC DISEASE
HEPCIDIN
Decreases stomach acidity
Gastrectomy or bariatric
Medication
Chronic Blood Loss
• _______or repeated______(e.g., from menstruation, gastrointestinal bleeding, or urinary tract issues) depletes the body’s iron stores.
• Specific causes include:
• Frequent blood donations.
• Paroxysmal nocturnal hemoglobinuria (PNH): A condition causing RBC destruction and hemoglobin loss through urine.
• Prolonged menorrhagia (heavy menstrual bleeding).
Chronic hemorrhage
blood loss
• Develops when the iron loss exceeds iron intake over time and storage iron is exhausted.
CHRONIC BLOOD LOSS
• HEME IRON CAN BE LOST:
• Repeated blood donations
• Chronic hemorrhage or hemolysis
• Chronic gastrointestinal bleeding
• Prolonged menorrhagia (heavy menstrual bleeding)
• Tumor or malignancies
• Urinary tract with kidney stones
• Paroxysmal nocturnal hemoglobinuria
• HEME IRON CAN BE LOST:
• Repeated blood donations
• Chronic hemorrhage or hemolysis
• Chronic gastrointestinal bleeding
• Prolonged menorrhagia (heavy menstrual bleeding)
• Tumor or malignancies
• Urinary tract with kidney stones
• Paroxysmal nocturnal hemoglobinuria
Iron is distributed in three main compartments:
- Iron stored as ferritin in bone marrow macrophages and liver cells.
- Iron carried in the blood by transferrin.
- Iron found in hemoglobin, myoglobin, and cytochromes, with hemoglobin iron and intracellular ferritin/hemosiderin comprising nearly 90% of the body’s total iron.
- Storage Compartment
- Transport Compartment
- Functional Compartment
Storage Compartment
• Location: (3)
• Forms: Stored as (2)
• Role: Acts as a reserve to supply iron during periods of increased demand or inadequate intake.
Liver, spleen, and bone marrow.
ferritin and hemosiderin.
Transport Compartment
• Location:
• Form: Bound to_____, a protein that delivers iron to cells.
• Role: Ensures the delivery of iron to tissues, especially the bone marrow for RBC production.
Blood plasma.
transferrin
Functional Compartment
• Location: (2) throughout the body.
• Forms: Predominantly as iron in (3) and other iron-containing enzymes.
• Role: Supports oxygen transport (hemoglobin), energy metabolism (cytochromes), and muscle oxygen storage (myoglobin).
RBCs and cellular components
hemoglobin, but also in myoglobin, cytochromes,
comprising nearly 90% of the body’s total iron.
ferritin/hemosiderin
Stages of IDA
Stage 1 - Storage Iron depletion
Stage 2 - Transpon iron depletion
Stage 3 - Functional iron depletion
- Iron stores (ferritin) begin to decline as the demand for iron exceeds intake.
- RBC production remains normal, and no anemia is present yet.
- Serum ferritin decreases, indicating declining stored iron.
Stage 1
- Laboratory Findings:
- Serum ferritin levels drop, but other parameters such as hemoglobin and RBC indices (MCV, MCH, MCHC) remain normal.
- Symptoms:
- No clinical symptoms; individuals appear healthy despite declining iron reserves.
Stage 1
- Storage iron is fully depleted.
- RBC production continues by relying on iron from the transport compartment and recycled iron from dying cells.
- Hemoglobin synthesis in newly produced RBCs decreases, leading to early signs of iron-restricted erythropoiesis.
- Serum iron and ferritin decrease; total iron-binding capacity (TIBC) increases, reflecting increased transferrin levels.
- Free erythrocyte protoporphyrin (FEP) accumulates due to insufficient iron for heme formation.
- Soluble transferrin receptor (sTfR) levels increase as iron-starved cells attempt to capture more iron.
Stage 2
- Laboratory Findings:
- Serum ferritin: Decreased.
- Serum iron: Decreased.
- TIBC: Increased.
- Bone marrow stain (Prussian blue): No stored iron visible.
- FEP and sTfR levels: Elevated.
Stage 2
- Symptoms:
- Still subclinical, though some non-specific symptoms like muscle weakness may appear.
- CBC findings remain within reference ranges, making detection difficult without specific iron studies.
Stage 2
- Hemoglobin production is severely restricted due to insufficient iron in both storage and transport compartments.
- RBCs become microcytic (small) and hypochromic (pale) due to inadequate hemoglobin content.
- Hepcidin levels decrease further to increase iron absorption, but dietary iron is insufficient to meet the demand.
Stage 3
- Laboratory Findings:
- Hemoglobin: Low.
- Hematocrit: Low.
- RBCs: Microcytic, hypochromic.
- Serum ferritin: Extremely low.
- FEP and sTfR levels: Continue to rise.
- Reticulocyte hemoglobin content: Decreased.
- Erythropoietin: Elevated but not as high as expected given the degree of anemia.
Stage 3
- Symptoms:
- Common Symptoms:
- Fatigue, weakness, shortness of breath (especially on exertion).
- Physical Signs:
- Pallor in the skin, conjunctivae, mucous membranes, or palmar creases.
- Common Symptoms:
Stage 3
- Severe Signs (less common in developed countries):
Glossitis Sore tongue due to iron deficiency in rapidly dividing epithelial cells.
Angular Cheilosis Inflamed cracks at the corners of the mouth.
Koilonychia “Spoon-shaped” fingernails due to long-standing deficiency.
Pica Cravings for non-food items like dirt, clay, or ice (pagophagia).
Stage 3
Stage 3
* Severe Signs (less common in developed countries):
Sore tongue due to iron deficiency in rapidly dividing epithelial cells.
Inflamed cracks at the corners of the mouth.
“Spoon-shaped” fingernails due to long-standing deficiency.
Cravings for non-food items like dirt, clay, or ice (pagophagia).
Glossitis
Angular Cheilosis
Koilonychia
Pica
They require iron for growth, especially for forming hemoglobin in red blood cells (RBCs), myoglobin in muscles, and cytochromes in cells.
Their bodies need more iron as they grow, and if their diet doesn’t meet these needs, they can develop iron deficiency.
Growing Children
• Growth requires iron for the cytochromes of all new cells
• Worsens with dietary inadequacies especially in poverty or neglect
GROWING CHILDREN
- Why less at risk?
They generally lose only small amounts of iron daily, which the body can easily replace. Therefore, iron deficiency is uncommon in these groups unless there is another cause, such as:
*\_\_\_\_\_\_\_ (e.g., ulcers, tumors, hemorrhoids) that causes blood loss * \_\_\_\_\_\_\_\_consumption can damage the stomach lining, leading to chronic bleeding and iron loss. * \_\_\_\_\_\_\_may not have a balanced diet or may experience reduced stomach acid, which affects iron absorption.
Men and Postmenopausal Women
Gastrointestinal disease
Regular aspirin use or alcohol
Elderly individuals
Infections and Parasitic Diseases:
*__________ can cause iron deficiency anemia by attaching to the intestinal wall and feeding on blood.
- Other parasitic infections like (3) can also lead to iron loss due to bleeding in the intestines or urinary tract.
Hookworms (e.g., Necator americanus and Ancylostoma duodenale)
Trichuris trichiura, Schistosoma mansoni, and Schistosoma haematobium
Active and Athletes:
*_________: Exercise, especially intense physical activity like running long distances, can cause hemoglobinuria (blood in urine), which results from red blood cell destruction (hemolysis) due to foot trauma. The hemoglobin released from these cells can be lost in the urine, leading to iron depletion.
- The loss of iron is usually small and not noticeable in normal conditions. However, if the activity is intense and repetitive (like long-distance running), it can lead to significant iron loss and eventually anemia.
- Well-trained athletes may be less prone to this due to better conditioning and adaptation to physical stress.
Soldiers or Long-Distance Runners
- Why at risk?
They lose blood each month, which means they lose iron. This monthly loss increases their need for iron. However, if their diet doesn’t provide enough iron, their iron stores become depleted.
* Adolescent girls are even more at risk because their bodies require more iron due to growth spurts.
Menstruating Women
- Why at risk?
During pregnancy, women need extra iron to support the developing baby and the growing blood volume in their own body. If the iron requirements are not met through diet or supplementation, the woman may lose a significant amount of iron, up to 1200 mg. This can affect future pregnancies and the health of the fetus.
- After childbirth, nursing mothers also need more iron to produce breast milk, adding to the iron depletion risk.
Pregnant and Nursing Women
