Hematology MCQs with Answer and Explanations | Chapter 1

Answer: 1.8 mg/ml

The desired concentration of EDTA (Ethylenediaminetetraacetic acid) in blood for best results typically 1.8 mg/ml. The exact concentration used may vary depending on the specific laboratory or test requirements, but concentrations within this range are commonly employed for anticoagulation and preserving the integrity of blood samples for various laboratory analyse

Answer: Neutrophil

During acute inflammation, the cells that produce the predominant response are neutrophils. Neutrophils are the first responders to an inflammatory site and play a crucial role in the initial defense against infection and tissue injury. They are responsible for phagocytosis of bacteria, foreign particles, and damaged cells, and they release various inflammatory mediators to help combat the threat and recruit other immune cells to the site of inflammation. While other cells like mast cells, macrophages, and lymphocytes are involved in the inflammatory response, neutrophils are the primary cell type during the early stages of acute inflammation.

Answer: 7.35 – 7.45

The normal pH of blood is in the range of 7.35 – 7.45. This slightly alkaline pH range is crucial for maintaining the proper functioning of various metabolic processes in the body. Any significant deviation from this range can have serious health implications.

Answer: Clot

A clot is formed when fibrin, a fibrous protein, forms a mesh that entraps blood cells, primarily platelets and red blood cells, to stop bleeding and seal a wound when there is vascular injury. This process is a part of the blood coagulation or clotting cascade. The other options mentioned (plaque, edema, tumor, rouleaux formation) are distinct phenomena with different characteristics and functions in the body.

Answer: Acute Myeloid Leukemia

Leukemic blasts with prominent granules, often resembling multiple Auer rods, are a characteristic feature of Acute Myeloid Leukemia (AML). Auer rods are needle-like inclusions within the cytoplasm of the leukemic blasts and are considered a hallmark of AML. In other conditions listed, such as Acute Lymphoid Leukemia (ALL), Chronic Lymphoid Leukemia (CLL), Myelodysplastic syndrome (MDS), and Chronic Myeloid Leukemia (CML), the presence of Auer rods is not a typical finding

Answer: Polycythemia vera

Polycythemia vera is a myeloproliferative neoplasm characterized by the overproduction of red blood cells. The majority of patients with polycythemia vera have a JAK2 mutation, specifically the JAK2V617F mutation. This mutation is not typically associated with the other conditions listed.

Answer: Sex linked disorder commonly affecting males

Hemophilia is a genetic disorder that primarily affects males and is inherited in an X-linked recessive pattern. It is caused by a deficiency or dysfunction of clotting factors, specifically Factor VIII (in Hemophilia A) or Factor IX (in Hemophilia B), not Factor X. Hemophilia results in a tendency to bleed excessively and can lead to bleeding into joints, muscles, and other tissues. It is not related to platelet dysfunction but rather involves problems with blood clotting factors.

Answer: Myelodysplastic syndrome

MDS is a group of blood disorders that affect the bone marrow, where blood cells are produced. In MDS, the bone marrow produces abnormal blood cells, including white blood cells. This can lead to a variety of symptoms, including fatigue, shortness of breath, easy bleeding or bruising, and increased risk of infection.

The other three options are not bone marrow disorders that result in the overproduction of white blood cells:

• Polycythemia vera (PV) is a blood disorder that is characterized by an overproduction of red blood cells.
• Hemochromatosis is a blood disorder that is characterized by an overproduction of iron.
• Thalassemia is a blood disorder that is characterized by an abnormality in the production of hemoglobin, the protein in red blood cells that carries oxygen.

Answer: Red blood cell

Red blood cells lack a nucleus. They are also known as erythrocytes and are unique among blood cell types in that they do not contain a nucleus. The absence of a nucleus allows red blood cells to have a biconcave shape, which maximizes their surface area for oxygen and carbon dioxide transport. This feature makes them efficient carriers of oxygen throughout the body. Platelets, white blood cells, and plasma cells all have nuclei.

Answer: Chemotaxis

The term for the process by which white blood cells move through blood vessel walls to reach infected tissues is Chemotaxis. Chemotaxis is the directed movement of white blood cells (leukocytes) in response to chemical signals, such as those released by bacteria, to migrate to the site of infection or inflammation. It is an essential part of the immune response, allowing white blood cells to locate and combat pathogens in tissues. Phagocytosis is the process by which cells engulf and digest particles, and coagulation is the formation of blood clots. Hemolysis is the destruction of red blood

Answer: Active thrombin

Thromboplastin is an activator of the extrinsic pathway of blood coagulation, and it, along with calcium ions, plays a crucial role in the conversion of prothrombin to thrombin. Thrombin is an enzyme that converts soluble fibrinogen into insoluble fibrin, leading to the formation of blood clots.

Answer: TTP

1. Platelet Count: A very low platelet count (29 x 10^3/μL) indicates thrombocytopenia.
2. PT (Prothrombin Time): The PT is within the normal range (12 seconds), suggesting that the patient’s clotting factors are functioning properly.
3. APTT (Activated Partial Thromboplastin Time): The APTT is also within the normal range (32 seconds), indicating that the intrinsic pathway of coagulation is not significantly affected.
4. Clinical Symptoms: Blurred vision, confusion, and petechiae are suggestive of microvascular thrombosis, which is characteristic of TTP.

In TTP, there is a deficiency of the enzyme ADAMTS13, leading to the formation of microthrombi, consumption of platelets, and subsequent thrombocytopenia. This is a medical emergency and requires prompt treatment with plasma exchange therapy. Other conditions listed (ITP, DIC, HUS) may also present with thrombocytopenia, but the specific combination of clinical features and coagulation profile in this case points towards TTP.

Answer: Defense against parasites

The primary function of eosinophils in the immune system is Defense against parasites. Eosinophils are a type of white blood cell (leukocyte) that plays a significant role in the body’s immune response to parasitic infections. They are particularly effective in combating multicellular parasites like helminths. Eosinophils release toxic granules containing enzymes and proteins that are toxic to parasites, aiding in their elimination. Eosinophils are less involved in phagocytosis of bacteria, killing of viruses, or antibody production compared to their role in defending against parasites.

Answer: Leukemia

The blood disorder characterized by uncontrolled proliferation of white blood cells, specifically in the bone marrow, is Leukemia. Leukemia is a type of cancer that affects the bone marrow and blood, leading to the overproduction of abnormal white blood cells. It can result in various types of white blood cells, such as lymphocytes or myeloid cells, depending on the specific subtype of leukemia. Hemophilia is a bleeding disorder, polycythemia vera involves an overproduction of red blood cells, and thrombocytosis is an elevated platelet count, which is not related to uncontrolled white blood cell proliferation.

Answer: 2 – 3 hours

The preservation of cellular morphology in blood samples collected with EDTA as an anticoagulant is most reliable within the first 2 to 3 hours after collection. After this time frame, cell structures may begin to deteriorate, and the accuracy of certain cellular measurements may be compromised.

Answer: Thalassemia

Thalassemia is not a congenital red blood cell membrane defect. It is a genetic disorder characterized by abnormal hemoglobin production rather than a structural defect in the red blood cell membrane. Hereditary Spherocytosis, Hereditary Stomatocytosis, Hereditary Ovalocytosis, and Hereditary Elliptocytosis are all congenital red blood cell membrane defects that result in various structural abnormalities in the red blood cell membrane, leading to different shapes and characteristics of the red blood cells. Thalassemia primarily affects the production of hemoglobin within the red blood cells.

Answer: Hemoglobin

Hemoglobin is an important constituent of red blood cells (RBCs). It is a protein that binds with oxygen in the lungs and carries it to tissues and organs throughout the body. The iron-containing heme groups in hemoglobin are responsible for binding and transporting oxygen.

Answer: 35-45%

The normal range for the hematocrit level in adult females is typically 35-45%. This value represents the proportion of a blood sample that consists of red blood cells and is expressed as a percentage. The normal range can vary slightly depending on the laboratory and population, but the range mentioned is a common reference range for adult females.

Answer: Factor VIII

Individuals with Hemophilia A have a deficiency of Factor VIII. Hemophilia A is a hereditary bleeding disorder characterized by a deficiency or dysfunction of clotting Factor VIII, which is essential for the formation of stable blood clots. This deficiency leads to a prolonged bleeding time and a tendency to bleed excessively even after minor injuries. Factor IX deficiency is associated with Hemophilia B, which is also known as Christmas disease. Factors I and II are not typically associated with hemophilia but play different roles in the clotting cascade.

Answer: All Points

Precautions that should be taken when using anticoagulated vials for blood collection include:

1. Do not push the blood through syringe: Avoid forcefully pushing blood into the anticoagulated vial to prevent hemolysis, which can affect test results.
2. Add exact desired volume of blood: Ensure you add the specified volume of blood accurately, as specified for the particular test, to obtain reliable results.
3. Mix gently after adding blood: After adding the blood to the vial, gently mix or invert it to ensure proper and uniform mixing of the blood with the anticoagulant, preventing clot formation and maintaining an appropriate sample for analysis.

Answer: EDTA

The PFA-100 (Platelet Function Analyzer-100) is a test used to assess platelet function and the effectiveness of platelet aggregation. It measures the time it takes for a platelet plug to form at a site of injury in a small, artificial blood vessel.

Thrombocytopenia (a low platelet count), aspirin (an antiplatelet drug), and anemia (a condition characterized by a decreased number of red blood cells or reduced hemoglobin) can all affect the PFA-100 Closure Time. However, EDTA, which is an anticoagulant commonly used in blood collection, is not typically associated with affecting PFA-100 results.

Answer: ESR

Heparin is often used to prevent blood clotting in blood samples collected for the ESR test. The ESR measures the rate at which red blood cells settle in a vertical tube of blood over time, and heparin is used to prevent clots from forming in the sample, allowing accurate ESR measurements. For other tests, different anticoagulants are typically used.

Answer: Chelating calcium

Trisodium citrate is an anticoagulant that is commonly used in blood collection tubes to prevent blood clotting. It works by binding to and sequestering the calcium ions in the blood, which is essential for the blood clotting process. By chelating calcium, trisodium citrate helps maintain the blood in a liquid, anticoagulated state, making it suitable for various laboratory tests that require unclotted blood samples

Answer: Haemoglobin Electrophoresis

Hemoglobin electrophoresis is a laboratory test that separates and identifies different types of hemoglobin in the blood. Beta thalassemia is characterized by alterations in the hemoglobin molecule, leading to abnormal forms of hemoglobin, such as HbA and HbF. Hemoglobin electrophoresis can detect these changes in hemoglobin composition and is an essential diagnostic tool for identifying beta thalassemia and determining its subtype. Other tests, such as blood complete picture, iron profile, and flow cytometry, may be used as part of the diagnostic process or to assess associated conditions, but they are not the primary tests for diagnosing beta thalassemia. Bone marrow examination is usually not required for routine diagnosis but may be considered in certain cases.

Answer: Chelates iron

EDTA effectively chelates (binds) calcium ions in the blood, preventing clotting and maintaining the integrity of blood samples for various laboratory tests. It also helps preserve cellular morphology by preventing clumping of platelets and other blood cells, which is advantageous for accurate blood cell analysis. However, EDTA is not primarily used to chelate iron; rather, it is used to chelate calcium. Other chelating agents are more suitable for binding iron.

Answer: Ethylene diamine tetra acetic acid

EDTA is a chelating agent commonly used in laboratories and clinical settings to bind and sequester metal ions, making it useful for various applications, such as anticoagulation of blood samples and as a metal ion stabilizer in chemistry and biochemistry.

Answer: Tuberculosis

Eosinophilia is characterized by an increased number of eosinophils, a type of white blood cell, in the blood or tissues. Eosinophilia is commonly associated with parasitic infections and allergic diseases, among other conditions. However, it is not typically a feature of tuberculosis, which is a bacterial infection caused by Mycobacterium tuberculosis. Eosinophils are more commonly involved in immune responses against parasites and in allergic reactions, not in the immune response against tuberculosis. Therefore, eosinophilia does not typically occur in tuberculosis.

Answer: Haemophilia

Mucosal bleeding and petechiae are common manifestations of bleeding disorders and conditions associated with platelet dysfunction.

1. Von Willebrand disease and 3. Idiopathic thrombocytopenic purpura (ITP) are both associated with platelet dysfunction and can cause mucosal bleeding and petechiae. Von Willebrand disease involves a deficiency of von Willebrand factor, which is essential for platelet adhesion, and ITP is characterized by a low platelet count.
2. Connective tissue disorders can also lead to mucosal bleeding and petechiae due to vascular fragility and abnormalities in blood vessel walls.
3. Storage pool diseases, which affect platelet granules, can result in platelet dysfunction and similar bleeding symptoms.

On the other hand, 2. Hemophilia is a condition characterized by a deficiency of clotting factors, particularly Factor VIII (in Hemophilia A) and Factor IX (in Hemophilia B), and is not primarily associated with platelet dysfunction. Hemophilia typically results in bleeding into joints and muscles rather than mucosal bleeding and petechiae.

Answer: Oxygen transport

The primary function of hemoglobin in red blood cells is Oxygen transport. Hemoglobin is a protein that binds with oxygen in the lungs and carries it through the bloodstream to the body’s tissues and organs. It plays a central role in delivering oxygen to cells and removing carbon dioxide, which is a waste product of cellular metabolism. While other functions like the immune response, phagocytosis, and blood clotting are essential components of the body’s defense and maintenance mechanisms, hemoglobin’s primary role is oxygen transport.

The other options are not primary functions of hemoglobin:

• Immune response: The immune system is responsible for defending the body against infection. Hemoglobin is not directly involved in the immune response.
• Phagocytosis: Phagocytosis is the process by which white blood cells engulf and destroy foreign invaders, such as bacteria and viruses. Hemoglobin is not directly involved in phagocytosis.
• Blood clotting: Blood clotting is a complex process that involves many different proteins, including hemoglobin. However, hemoglobin is not a primary function of blood clotting.

Answer: EDTA

EDTA is commonly used to preserve blood samples for CBC testing because it efficiently prevents blood clotting, making it suitable for maintaining the integrity of the blood sample and ensuring accurate cell counts and measurements.

Answer: Plasma contains coagulation factors while serum does not

Plasma is the liquid component of blood in which the blood cells are suspended, and it contains all the clotting factors. When blood is allowed to clot, plasma separates from the clotted blood, leaving behind serum. Serum is essentially plasma without the clotting factors, as they are used in the clotting process. This difference in the presence of clotting factors is significant when conducting coagulation studies or tests that require the measurement of specific clotting parameters.

Answer: Sickle cell anemia

The hereditary disorder that causes abnormal hemoglobin is Sickle Cell Anemia. Sickle cell anemia is a genetic disorder that affects the hemoglobin protein in red blood cells, causing it to take on a “sickle” or crescent shape under certain conditions. This abnormal hemoglobin can lead to a variety of health issues, including anemia, pain crises, and other complications. Thrombocytopenia is a condition characterized by a low platelet count, leukemia is a type of blood cancer, and hemophilia is a bleeding disorder, but none of these conditions primarily involve abnormal hemoglobin.

Answer: Soluble Precipitates

Oxalates are naturally occurring substances that are found in many plants, such as spinach, rhubarb, and nuts. Oxalates can also be produced in the body by the metabolism of certain foods, such as vitamin C.

When oxalates are consumed in excess, they can bind to calcium in the digestive tract to form insoluble calcium oxalate crystals. These crystals can be excreted in the urine, but they can also form kidney stones.

Kidney stones are hard deposits of minerals and salts that form in the kidneys. They can cause severe pain, bleeding, and other complications.

Oxalates can also form soluble precipitates in the blood. These soluble precipitates are not as likely to form kidney stones, but they can still cause problems. For example, soluble calcium oxalate crystals can irritate the lining of the bladder and cause pain and inflammation.

The other options are not correct:

• Irreversible clot: An irreversible clot is a blood clot that cannot be dissolved. Oxalates do not cause irreversible clots.
• Platelet agglutinates: Platelet agglutinates are clumps of platelets. Oxalates do not cause platelet agglutination.
• Rouleaux formation: Rouleaux formation is the stacking of red blood cells in a column like shape. Oxalates do not cause rouleaux formation.
• Reversible clot: A reversible clot is a blood clot that can be dissolved. Oxalates do not cause reversible clots.

Answer: Hemolysis

The term for the process of breaking down red blood cells and releasing their components is Hemolysis. Hemolysis refers to the rupture or lysis of red blood cells (erythrocytes), leading to the release of their contents, including hemoglobin, into the surrounding fluid, such as plasma. This process can occur in various circumstances, both within the body and in laboratory settings. It is essential for releasing hemoglobin, which can then be processed and metabolized. Hemostasis, on the other hand, is the process of stopping bleeding, typically by forming a blood clot. Hemoglobin synthesis is the production of hemoglobin, and hematopoiesis is the formation of blood cells in the bone marrow.

Answer: Blood clotting

The primary function of platelets in the blood is Blood clotting. Platelets, also known as thrombocytes, play a central role in hemostasis, which is the body’s process for preventing excessive bleeding when a blood vessel is injured. They adhere to the site of injury, aggregate together, and release various factors that initiate the formation of a blood clot, sealing the wound and stopping the bleeding. While platelets are important for blood clotting, oxygen transport is mainly carried out by red blood cells, and the immune response is primarily mediated by white blood cells. Platelets are not directly involved in pH regulation.

Answer: Bone marrow

The bone marrow is primarily responsible for the production of red blood cells (RBCs) in the human body. Bone marrow, found in the cavities of certain bones, is a key hematopoietic (blood-forming) organ. It contains stem cells that give rise to the various blood cell types, including red blood cells, white blood cells, and platelets. The kidneys play a role in the production of a hormone called erythropoietin, which stimulates the bone marrow to produce red blood cells in response to low oxygen levels in the blood. The spleen and liver have other functions in the blood, such as filtering and storage, but they are not the primary sites for the production of RBCs.

Answer: Serum ferritin

Serum ferritin is indeed a commonly used blood test to assess iron stores in the body, and elevated levels of serum ferritin can be indicative of iron overload. However, while serum ferritin is a valuable indicator of iron status, including iron overload, a liver biopsy is considered the gold standard for diagnosing and quantifying circulatory iron overload, especially in conditions like hereditary hemochromatosis.

Answer: 5 – 7 Days

The average lifespan of platelets is approximately 5 – 7 days in the circulation. After this time, they are removed from circulation and replaced by new platelets produced in the bone marrow.

Answer: Complete blood count (CBC)

The laboratory test that measures the number of white blood cells in a blood sample is the Complete Blood Count (CBC). A CBC is a comprehensive blood test that provides various measurements, including white blood cell count (WBC), red blood cell count (RBC), hemoglobin level, hematocrit, platelet count, and other related parameters. It is an essential diagnostic tool for assessing a person’s overall health and can help identify a wide range of conditions, including infections, anemias, and other hematological disorders. Hemoglobin and hematocrit, while measured in a CBC, specifically relate to red blood cells, not white blood cells. Prothrombin time (PT) is a test used to assess the clotting function of the blood and is not used to measure white blood cells.

Answer: 120 Days

Red blood cells (RBCs) have a typical lifespan of approximately 120 days in the circulation. After this period, they are removed from circulation and destroyed, primarily in the spleen and liver, by the reticuloendothelial system. Therefore, RBC destruction occurs after around 120 days in the body.

Answer: Neutrophils

Neutrophils are the most abundant type of white blood cells in the peripheral blood. They make up a significant portion of the total white blood cell count and are an essential component of the body’s immune response. Neutrophils play a primary role in the defense against bacterial infections and are often the first responders to sites of infection or tissue injury. Monocytes, basophils, and eosinophils are also types of white blood cells but are present in smaller numbers compared to neutrophils in the peripheral blood.

Answer: Factor XIII

Factor XIII, also known as fibrin-stabilizing factor, plays a critical role in the coagulation cascade by cross-linking fibrin molecules to form a stable and insoluble clot. This cross-linking process is essential for the effective sealing of blood vessel injuries and wound healing.

Answer: Chelating calcium

EDTA (Ethylenediaminetetraacetic acid) binds to calcium ions in the blood, preventing the calcium-dependent coagulation cascade. This action inhibits the coagulation process and keeps the blood from clotting during laboratory tests that require anticoagulated blood samples. It does so by sequestering the calcium required for the coagulation factors to function, thus preventing the blood from clotting. The other options listed are not the primary mechanism by which EDTA acts as an anticoagulant.

Answer: Median Cubital Vein

The site of first choice for venipuncture is typically the Median Cubital Vein. This vein is often preferred because it is usually well-anchored and easy to access, making it a common choice for drawing blood or performing venipuncture procedures. The other veins mentioned (Cephalic Vein, Ulnar Vein, and Basilic Vein) may also be used if the median cubital vein is not accessible or suitable, depending on the patient’s anatomy and the specific circumstances.

Answer: Elevated absolute neutrophil count

Neutrophilia is a condition characterized by an elevated absolute neutrophil count, which means there is an abnormally high number of neutrophils in the blood. Neutrophils are a type of white blood cell involved in the body’s immune response to infection and inflammation. An increase in neutrophils can be seen in various medical conditions, such as infections, inflammation, or certain types of leukemia. The other options are related to different aspects of white blood cell counts, but they do not represent neutrophilia.

Answer: Multiple myeloma

Rouleaux formation refers to the stacking or clumping of red blood cells, which can occur when there is an increase in the levels of certain proteins in the blood, particularly immunoglobulins. Multiple myeloma is a cancer of plasma cells, which are a type of white blood cell that produces immunoglobulins (antibodies). In multiple myeloma, excessive production of immunoglobulins can lead to increased Rouleaux formation, which is a characteristic finding in this condition. Sickle cell anemia, polycythemia, hyperalbuminemia, and hereditary spherocytosis are not typically associated with increased Rouleaux formation.

Answer: Anemia

The condition characterized by a deficiency of red blood cells, resulting in fatigue and weakness, is Anemia. Anemia is a condition where the body lacks a sufficient number of healthy red blood cells or hemoglobin to carry an adequate amount of oxygen to the body’s tissues, leading to symptoms like fatigue, weakness, and sometimes paleness. Leukemia and lymphoma are types of blood cancers, and hemophilia is a bleeding disorder, but they are not characterized by a deficiency of red blood cells.

Answer: Hemostasis

The term that refers to the process of stopping bleeding, typically by forming a blood clot, is Hemostasis. Hemostasis is the body’s physiological response to prevent excessive bleeding when a blood vessel is injured. It involves a complex series of events, including blood vessel constriction, platelet activation, and the coagulation cascade, ultimately leading to the formation of a blood clot that stops the bleeding. Hemolysis is the destruction of red blood cells, hemoglobin synthesis is the production of hemoglobin, and hematopoiesis is the formation of blood cells in the bone marrow.

Answer: Reduction in absolute neutrophil count

Neutropenia is a condition characterized by a lower-than-normal number of neutrophils, which are a type of white blood cell, in the blood. It is associated with an increased risk of infections due to a weakened immune response, primarily because of the reduced number of neutrophils.

Answer: Heinz bodies

Heinz bodies are inclusions in red blood cells that consist of denatured or precipitated hemoglobin. They are often associated with certain hemolytic anemias, oxidant damage, or exposure to certain chemicals or drugs that can cause damage to the hemoglobin molecule. The other options mentioned, such as Pappenheimer bodies, basophilic stippling, Cabot rings, and Howell-Jolly bodies, are associated with different conditions or cellular features in red blood cells.