Pathophysiology Exam 2 Ultimate Review Guide

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Plasma

Liquid component of blood that contains clotting factors

Serum

Plasma without clotting factors

What is blood made up of

Plasma and formed elements (RBCs, WBCs, platelets)

Hematocrit

Percentage of RBCs found in any volume of blood

Normal range for hematocrit

35-44%

Erythropoiesis

Creation of RBCs

Erythropoietin

Hormone that is released to initiate erythropoiesis, created by kidneys

Physiological Causes of Erythropoietin Production

• Menses

• Exercise

• High altitude

Pathological Causes of Erythropoietin Production

• Sickle cell disease

• Cellular injury

How much heme and globin groups are in a single hemoglobin

4

Composition of heme

• Iron

• Protoporphyrin-IX

Which cells are responsible for the breakdown of hemoglobin

Macrophages

What is the byproduct of heme breakdown

Bilirubin

Unconjugated bilirubin

Bilirubin that is not water soluble, bound to albumin, and transported to the liver

Function of transferrin

Transports iron from the spleen (think of it as a taxi)

Function of ferritin

Stores iron in the liver

Hemostasis

Stoppage of bleeding

Types of hemostasis

• Primary (vasospasm+platelet plug)

• Secondary (coagulation cascade)

Primary hemostasis

• Arteriolar vasospasm occurs

• von Willebrand factor bridges wounded area to platelets (platelet adhesion)

Secondary hemostasis

Initiates positive feedback loop to accumulate clotting factors and proteins

Dr. K states that anemia is not a disease, rather it’s a sign of an underlying disorder. Is Dr. K’s statement factually correct?

Yes

Anemia

Functional inability of the blood to supply tissues with adequate oxygen for proper function

Reticulocyte

Young and immature RBC

Mean corpuscular volume (MCV)

Average RBC size

Classifications of MCV on a complete blood count (CBC)

• microcytic (<80)

• normocytic (80-100)

• macrocytic (>100)

Mean cell hemoglobin concentration (MCHC)

hemoglobin concentration per RBC

Classifications of chromicity

• Normochromic

• Hypochromic

General symptoms of anemia

• Fatigue, low energy

• Pale skin

• Tachycardia

• Shortness of breath

• Dizziness

Macrocytic anemia (Megaloblastic anemia)

Anemia in which DNA synthesis is disfunctional, causing large RBCs to be produced

Primary causes of macrocytic anemia

Deficiencies of vitamin B12 or folate (B9)

Which part of the small intestine is responsible for the absorption of vitamin B12

Jejunum

Causes of Vitamin B12 deficiency

• Pernicious anemia

• Malnutrition

• Malabsorption

• Vegan diet

Causes of folate deficiency

• Malnutrition

• Malabsorption

• Chronic alcohol usage

• Increased bodily demand (ex: pregnancy)

In macrocytic anemia, a lack of intrinsic factor that is autoimmune is which type of anemia?

Pernicious anemia

In macrocytic anemia, a lack of intrinsic factor that is not caused by autoimmune factors is a result of what procedure?

Gastric bypass surgery

Diseases associated with malabsorption in folate deficiency

• Crohn’s disease (chronic inflammation of GI tract)

• Celiac disease (autoimmune disease caused by adverse reaction to gluten)

Pernicious anemia

Type of macrocytic anemia in which autoimmune cells destroy parietal cells

What type of anemia is pernicious anemia

Macrocytic anemia

Causes of pernicious anemia

• Vitamin B12 deficiency due to lack of intrinsic factor

• Gastrectomy (removal of stomach)

• Congential IF deficiency

Demyelination is unique which vitamin

Vitamin B12

Absorption location of folate

Upper small intestine

Diagnostics for macrocytic anemia

• Complete blood count

• Testing antibodies against parietal cells / intrinsic factor

Treatment for pernicious anemia

Parenteral (IV) or Intramuscular (IM) administration of Vitamin B12

Treatment for non-pernicious macrocytic anemia

• Intramuscular (IM) injections or oral supplements of B12

• Folate supplements

Microcytic Anemia

Anemia that is characterized by abnormally small cells due to reduced hemoglobin

Examples of microcytic anemia

• Iron deficiency anemia

• Sickle cell thalassemia

• Anemia of chronic disease

Iron deficiency anemia

Type of microcytic anemia caused by a lack of iron

Causes of iron deficiency anemia

• Chronic blood loss (menstruation, malignancy)

• Inadequate absorption (low iron diet, GI disease, malabsorption)

• Increased bodily demand (pregnancy)

Why is cow’s milk bad for infants

It has low iron content, and calcium inhibits non-heme iron absorption

Early symptoms of iron deficiency anemia

• Fatigue/weakness

• Shortness of breathe

• Paleness

Progressive symptoms of iron deficiency anemia

• Brittle, spoon shaped nails

• Dysphagia (difficulty swallowing foods)

• Painful oral ulcerations

Level of blood iron that indicates iron deficiency anemia

7-8g/dL

Evaluation to diagnose iron deficiency anemia

• Hematocrit

• Peripheral blood smear

• Bone marrow iron stain

Normocytic Anemia

Mild to moderate form of anemia caused by decrease in erythropoiesis

• Blood cells are normally sized

Causes of normocytic anemia

• Acute blood loss

• Hemolysis

• Hypothyroidism

• Chronic kidney disease

• Bone marrow suppression

Hepcidin

A liver produced hormone that inhibits ferroportin

Effect of high levels of hepicidin

Hepicidin leads to iron being trapped in cells, making less iron available for hemoglobin production

If someone has a chronic disease, you would expect hepicidin levels to be ____, and iron absorption to be _____.

higher, lower

Hemorrhage

loss of blood

Petechiae

Minute patch of bleeding that is 1-2 mm in diameter

Size of petechiae

1-2 mm

Ecchymoses

Bruise that is 1-2 cm in diameter

Size of ecchymoses

1-2 cm

Purpura

Patches that are between 3mm-1cm in diameter

Size of purpura

3mm-1cm

Testing for platelet dysfunction

• CBC

• Peripheral blood smear

• Prothrombin Time (PT)

• INR

• aPTT

• Bleeding time

von Willebrand disease

A genetic disease in which the body has an abnormality of von Willebrand factor (vWF) production

Inheritance pattern of von Willebrand disease

Autosomal dominant

von Willebrand factor function

Facilitates platelet adhesion

What is the most common inherited bleeding disorder worldwide

von Willebrand disease

Coagulation Cascade Dysfunction causes

• Vitamin K deficiency

• Inherited diseases (Hemophilia)

• Defective absorption and production

Vitamin K

Fat-soluble vitamin needed for the production of prothrombin, factors VIII/IX/X, and clotting proteins

Causes of vitamin K deficiency

• Newborns

• Liver disease

• Anticoagulant antibiotics

Diseases associated with Coagulation Cascade Disfunction for malabsorption

• Biliary disease

• Liver disease

Hemophilia

A genetic disease in which the body has a deficiency of factor XIII (A) or factor IX (B)

Inheritance pattern of Hemophilia

X-linked recessive

Symptoms of Hemophilia

• Prolonged bleeding after minor trauma

• Bleeding into joints, urine (hematuria), or feces

Difference between Hemophilia A and B

A uses factor XIII while B uses factor IX

Desseminated Intravascular Coagulation (DIC)

An acquired, life-threatening disorder in which coagulation and hemorrhage happens at the same time

Causes of Desseminated Intravascular Coagulation (DIC)

• Gram negative bacterial infection (sepsis)

• Trauma

• Pregnancy

• Transfusion reaction

Symptoms of Desseminated Intravascular Coagulation (DIC)

• Bleeding

• Bruising

• Cyanosis

Treatment of Desseminated Intravascular Coagulation (DIC)

• Replacement therapy (factors, platelets)

• Replace anticoagulants

• Eliminate underlying pathology

Sickle cell anemia

A genetically inherited form of normocytic anemia in which blood cells have a sickle shape, resulting in hemoglobin not being carried

Inheritance pattern of sickle cell disease

Autosomal recessive

Intrinsic clotting

Blood clotting that takes place inside the blood vessel

Extrinsic clotting

Blood clotting that takes place outside the blood vessel

Normochromic

Normal hemoglobin content

Hypochromic

Less hemoglobin content

Fibrinolysis

Breakdown of a blood clot

Dr. K is presented with a 52 year old patient named Francis who is experiencing shortness of breathe and fatigue. Dr. K ordered an MCV test and found that the size of his red blood cells are 123 fL, as well as low intrinsic factor. You find that he has macrocytic anemia. He has no history of autoimmune disease, but notes that he used to be severely obese.

What is the most likely cause of his macrocytic anemia?

Vitamin B12 deficiency due to gastric bypass surgery

Dr. K is evaluating a 20 year old patient who suspects he has anemia. After some tests, Dr. K notes that he has macrocytic anemia caused by autoimmune cells attacking parietal cells in the small intestine.

Which of the following diseases would be the correct diagnosis for Dr. K to give

Pernicious anemia

Dr. K recalls a case study in which a patient, WN, presented to a clinic with his dad in 2014 after complaining about fatigue and shortness of breath. Tests shows that microcytic anemia was remarkable for WN. Doctors said that WN was affected with the most common cause of anemia worldwide.

After reviewing the case study, Dr. K can conclude that WN was diagnosed with

Iron deficiency anemia

Dr. K recalls a case study in which a patient, WN, presented to a clinic with his dad in 2014 after complaining about fatigue and shortness of breath. Doctors concluded that WN was affected with iron deficiency anemia. WN was 7 years old at the time of the case study and have no significant findings for malignancy or malabsorption.

What was the most likely cause of WN’s iron deficiency

Low iron diet

Dr. K evaluates a patient, WN2, who has decreased erythropoiesis due to hypothyroidism and chronic inflammation. WN2 most likely has

Normocytic anemia

Dr. Marill evaluates a kid with Hemophilia A who fell over a rock at recess. Which factor should Dr. Marill provide the child to stop the bleeding?

Factor XIII

Common diagnostic tools for Cardiovascular diseases

• Electrical studies (EKG)

• Biomarkers (Troponin I, CK-MB, CBC)

• Functional Testing (stress, coronary angiography)