MLS 435: Platelets and Leukemias Exam Review

Set of flashcards covering key concepts related to platelets and leukemias for exam preparation.

What is endomitosis?

A process where a cell undergoes nuclear division without cytokinesis, resulting in larger cells with multiple copies of chromosomes.

What is the purpose of the platelet cytoskeleton?

To provide structural support and facilitate the shape change and functioning of platelets during hemostasis.

What are the steps of platelet plug formation?

1. Adhesion to the site of vascular injury, 2. Activation and shape change, 3. Aggregation with other platelets.

What receptor and protein are involved in platelet plug formation?

The GPIb receptor and von Willebrand Factor (vWF) are critical for adhesion and aggregation.

What is the function of platelets?

To play a key role in hemostasis by forming a platelet plug and releasing substances that promote coagulation.

What are the two main types of granules found in platelets?

Alpha granules and dense granules, which contain various proteins and factors important for coagulation.

What is the end product of secondary hemostasis?

Fibrin, which stabilizes the platelet plug.

What pathways are included in secondary hemostasis?

Intrinsic pathway and Extrinsic pathway, leading to the common pathway of coagulation.

What is the Fibrinolytic system?

The system responsible for the breakdown of fibrin in blood clots, primarily through plasmin activity.

What are testing methods for primary hemostasis?

Platelet count, bleeding time, and platelet function assays.

What is the difference between quantitative and qualitative testing methods?

Quantitative testing measures the number of platelets, while qualitative testing assesses their function.

What is the use for PT, PTT, and INR testing?

PT (Prothrombin Time) assesses extrinsic pathway, PTT (Partial Thromboplastin Time) assesses intrinsic pathway, and INR (International Normalized Ratio) standardizes PT results.

What are causes of thrombocytopenia?

Increased destruction, decreased production, or sequestration of platelets.

What are causes of thrombocytosis?

Reactive thrombocytosis due to inflammation, infection, or iron deficiency; or primary thrombocythemia.

What types of bleeding are associated with coagulation disorders?

Spontaneous bleeding, prolonged bleeding after injury, and bleeding into joints or muscles.

What is the pathophysiology of Immune Thrombocytopenic Purpura (ITP)?

An autoimmune disorder where the immune system mistakenly attacks platelets, leading to low counts.

What are the two most common factor deficiencies that cause hemophilia?

Hemophilia A (factor VIII deficiency) and Hemophilia B (factor IX deficiency).

How is hemophilia inherited?

X-linked recessive inheritance, primarily affecting males.

What is the underlying cause of von Willebrand's disease?

A deficiency or dysfunction of von Willebrand factor, which is crucial for platelet adhesion.

What differentiates Bernard-Soulier Disease and Glanzmann’s Thrombasthenia?

Bernard-Soulier Disease is due to GPIb deficiency, affecting adhesion, while Glanzmann’s Thrombasthenia is due to GPIIb/IIIa deficiency affecting aggregation.

What are the vitamin K dependent factors?

Factors II (Prothrombin), VII, IX, and X.

What conditions can lead to vitamin K deficiency?

Malabsorption syndromes, warfarin use, and liver disease.

What is the mechanism of Disseminated Intravascular Coagulation (DIC)?

An excessive activation of the coagulation cascade, leading to widespread clotting and bleeding.

What are risk factors for thrombosis?

Stasis of blood flow, endothelial injury, and hypercoagulability.

What is the most common site to collect bone marrow?

The posterior iliac crest.

What is the difference between Aspirate and Core bone marrow samples?

Aspirate provides a liquid sample for cell analysis, while Core gives a solid sample for architecture assessment.

What is found in the buffy coat?

White blood cells and platelets.

What is hemosiderin?

An intracellular storage form of iron, typically found in excess in iron overload conditions.

What are the steps of flow cytometry?

Sample preparation, labeling with fluorescent antibodies, passing through a laser, and data analysis.

What is leukemia?

A cancer of the blood or bone marrow characterized by an abnormal increase in white blood cells.

Which cells are affected in Acute Lymphoblastic Leukemia (ALL) and Acute Myeloid Leukemia (AML)?

ALL affects lymphoid progenitor cells, while AML affects myeloid progenitor cells.

What are favorable predictors for acute leukemia prognosis?

Younger age, lower initial white blood cell count, and presence of certain genetic mutations.

What are typical findings in acute leukemia?

Immature cells (blasts), symptoms like fatigue and bleeding, and abnormal CBC results.

What are the characteristics of Chronic Lymphocytic Leukemia (CLL)?

Typically affects older adults, involves B lymphocytes, and may show elevated total WBC count.

What is the most common leukemia found in children?

Acute Lymphoblastic Leukemia (ALL).

What tests are needed to diagnose leukemia?

Blood tests, bone marrow biopsy, and genetic tests.

What are the WHO criteria for diagnosing leukemia based on blast count?

At least 20% blasts in the bone marrow or peripheral blood.

What disorder is associated with the Philadelphia chromosome?

Chronic Myeloid Leukemia (CML), with the abnormal protein being BCR-ABL.