Disorders of Red Blood cells Flashcards
What are red blood cells (RBCs) and what do they do?
RBCs (erythrocytes) are the body’s oxygen transporters! They carry oxygen using hemoglobin (Hgb) to keep your body running!
What are the two major RBC disorders?
✔️ Anemia – Not enough RBCs 🚨 (Low oxygen delivery!)
✔️ Polycythemia – Too many RBCs ⚠️ (Blood gets thick!)
What is erythropoiesis?
The process of making new RBCs in the bone marrow!
What triggers RBC production?
Low oxygen (hypoxia)! The kidneys release erythropoietin (EPO), which tells the bone marrow to make more RBCs!
What happens to old RBCs?
They live ~120 days then get removed by the spleen! The heme part breaks down into bilirubin, which gives urine and feces their color.
What is hemoglobin (Hgb)?
A protein in RBCs that carries oxygen!
✔️ Hgb is made of 4 chains (2 alpha, 2 beta)
✔️ Each chain has iron (Fe), which binds oxygen!
What is hemoglobinopathy?
Abnormal hemoglobin – Example: Sickle Cell Anemia (Hgb S)! 🚨
Why do we need iron (Fe)?
Iron is essential for hemoglobin – without it, RBCs can’t carry oxygen properly!
✔️ Iron is stored in ferritin (liver, spleen, bone marrow)
✔️ Transferrin carries iron through the blood
✔️ TIBC (Total Iron Binding Capacity) – High when iron is low!
What is Hematocrit (Hct)?
The percentage of blood that is RBCs!
✔️ Males: 45–52%
✔️ Females: 37–48%
What does MCV (Mean Corpuscular Volume) measure?
RBC size!
✔️ Microcytic (Small RBCs) → Iron Deficiency
✔️ Normocytic (Normal RBCs) → Acute Blood Loss
✔️ Macrocytic (Large RBCs) → Vitamin B12/Folate Deficiency
What happens if you lose too much blood?
🚑 Hypovolemic shock! If you lose 1,000mL or more, your body can’t carry enough oxygen!
✔️ Acute Blood Loss – Trauma, surgery, clotting disorders
✔️ Chronic Blood Loss – GI bleed (dark stool), heavy periods (menorrhagia)
What is hemolytic anemia?
RBCs break down faster than they can be replaced!
✔️ Causes:
• Sickle Cell Disease – Misshapen RBCs clog blood flow
• Autoimmune diseases – Your immune system attacks RBCs
• Blood transfusion reactions – Wrong blood type!
✔️ Signs:
• Jaundice (Too much bilirubin from RBC breakdown!)
• Dark urine (Extra bilirubin gets peed out!)
Why does iron deficiency cause anemia?
Without iron, hemoglobin can’t form properly!
✔️ Causes:
• Poor diet (low iron foods!)
• Chronic blood loss (GI bleeding, heavy periods)
✔️ Signs:
• Pale skin
• Brittle nails (Koilonychia – spoon-shaped nails)
• Craving ice, dirt, or starch (PICA)!
✔️ Treatment:
• Iron supplements (Ferrous sulfate) + Vitamin C
Why is B12 important for RBCs?
B12 is needed for DNA synthesis in RBCs! Without it, RBCs become big and weak!
✔️ Causes:
• Lack of intrinsic factor (Pernicious anemia!)
• Gastric bypass, Crohn’s disease
• Strict vegan diet
✔️ Signs:
• Glossitis (swollen, red tongue)
• Numbness/tingling in hands & feet
• Unsteady walking (gait issues)
✔️ Treatment:
• B12 injections (if absorption is an issue!)
What determines blood type?
Antigens on RBCs!
✔️ A blood = Has A antigen, makes Anti-B antibodies
✔️ B blood = Has B antigen, makes Anti-A antibodies
✔️ AB blood = Has both A & B antigens, NO antibodies (Universal Recipient!)
✔️ O blood = No antigens, has Anti-A & Anti-B antibodies (Universal Donor!)
What is Rh factor?
Another antigen! Rh+ can receive Rh+ & Rh-, but Rh- can only receive Rh-.
✔️ Rh- mom & Rh+ baby → Hemolytic Disease of the Newborn!
✔️ Treatment? RhoGAM shot!
What is the mnemonic for types of anemia?
Types of Anemia Mnemonic – “Iron, Blood, Cells, B12!”
✔️ Iron Deficiency (Pale, spoon nails, craving ice!)
✔️ Blood Loss (GI bleeding, heavy periods!)
✔️ Cell Destruction (Hemolytic – jaundice, dark urine!)
✔️ B12 Deficiency (Big cells, numbness, unsteady walking!)
What is the blood type hack?
Blood Type Hack:
✔️ Type O = “Zero Antigens” (Universal Donor!)
✔️ Type AB = “All Antigens” (Universal Receiver!)
