Hematopathology Practice Questions

Q: The Rumpel Leede test measures what?

Capillary fragility. The **Rumpel-Leede test**, also known as the **Capillary Fragility Test** or the Tourniquet Test, is a clinical diagnostic tool used to assess the structural integrity of capillary walls and platelet function. **Why Option C is correct:** The test involves applying a blood pressure cuff to the upper arm and inflating it to a point midway between the systolic and diastolic blood pressure for 5 minutes. If the capillaries are fragile or if there is significant thrombocytopenia, the increased intraluminal pressure causes them to rupture, resulting in the formation of **petechiae** [1]. A positive test (usually >10–20 petechiae in a 1-inch square area) indicates **capillary fragility**. It is classically positive in conditions like **Dengue Hemorrhagic Fever**, Vitamin C deficiency (Scurvy), and various thrombocytopenic states. **Why other options are incorrect:** * **Bleeding Time (A):** Measures the time taken for a standardized skin wound to stop bleeding; it assesses platelet adhesion and aggregation, not capillary wall strength. * **Platelet Count (B):** This is a quantitative laboratory measurement (CBC) and cannot be determined by a physical tourniquet test, though low counts often lead to a positive Rumpel-Leede result [2]. * **ESR (D):** Erythrocyte Sedimentation Rate is a non-specific marker of inflammation and is unrelated to capillary integrity. **High-Yield Clinical Pearls for NEET-PG:** * **Dengue:** The Tourniquet Test is a key WHO criterion for the clinical diagnosis of Dengue. * **Scurvy:** Defective collagen synthesis leads to weak vessel walls and a positive Rumpel-Leede test. * **Hess Test:** Another name for the Rumpel-Leede test. * **Limitation:** It is not specific; it can be positive in both qualitative platelet defects (e.g., Glanzmann's) and quantitative defects (thrombocytopenia).

Q: Which of the following is a feature of disseminated intravascular coagulation (DIC)?

Reduced plasma fibrinogen. **Explanation:** Disseminated Intravascular Coagulation (DIC) is a complex consumptive coagulopathy characterized by systemic activation of the coagulation cascade [1]. This leads to the widespread formation of fibrin microthrombi, which paradoxically results in the **exhaustion of clotting factors and platelets**, leading to severe hemorrhage. **Why Option B is Correct:** In DIC, there is massive conversion of fibrinogen to fibrin due to excess thrombin [1]. Simultaneously, secondary fibrinolysis is activated, leading to the breakdown of fibrinogen. This dual process results in **hypofibrinogenemia (reduced plasma fibrinogen)**, which is a hallmark laboratory finding of the condition [1]. **Why Other Options are Incorrect:** * **A & D (Normal PT and Clotting Time):** Because DIC consumes clotting factors (Factors V, VIII, and X), the **Prothrombin Time (PT)**, **Activated Partial Thromboplastin Time (aPTT)**, and **Clotting Time (CT)** are all characteristically **prolonged**, not normal [1][2]. * **C (Normal Platelet Count):** Platelets are rapidly consumed during the formation of microthrombi [3]. Therefore, **thrombocytopenia** (reduced platelet count) is a consistent feature of DIC [1]. **High-Yield Clinical Pearls for NEET-PG:** * **Best Screening Test:** Platelet count and PT (both will be abnormal) [1][2]. * **Most Specific Test:** Elevated **D-dimer** or Fibrin Degradation Products (FDPs) [1]. * **Peripheral Smear:** Presence of **Schistocytes** (fragmented RBCs) due to microangiopathic hemolytic anemia (MAHA). * **Common Triggers:** Sepsis (most common), Obstetric complications (Abruptio placentae), and Malignancy (APML - M3) [1].

Q: The Kleihauer Betke test for detecting fetal erythrocytes is based on which principle?

HbF is more resistant to acid elution than HbA.. ### Explanation The **Kleihauer-Betke (KB) test** is the gold standard for quantifying the volume of **fetal-maternal hemorrhage (FMH)**. **1. Why Option C is Correct:** The test relies on the biochemical difference between **Hemoglobin F (fetal)** and **Hemoglobin A (adult)**. When a maternal blood smear is exposed to an **acid bath (citrate-phosphate buffer)**, adult hemoglobin (HbA) is unstable and leaches out of the cells, leaving behind empty "ghost cells." In contrast, fetal hemoglobin (HbF) is **acid-resistant** and remains within the erythrocytes. When a counterstain (like eosin or erythrosin) is applied, the fetal cells take up the stain and appear bright pink/dark, while maternal cells appear pale or colorless. **2. Analysis of Incorrect Options:** * **Option A:** Cell size is not the distinguishing factor; both fetal and adult RBCs are similar in size (though fetal RBCs have a slightly higher MCV, it is not the basis for this chemical test). * **Option B:** While HbF does have a higher oxygen affinity than HbA, this physiological property is used for gas exchange in utero, not for laboratory elution tests. * **Option D:** The staining difference is a *result* of the acid elution process, not a primary difference in the innate staining affinity of the hemoglobins themselves. **3. Clinical Pearls for NEET-PG:** * **Indications:** Used to calculate the dose of **Rh Anti-D immunoglobulin** required after a large FMH (e.g., trauma, placental abruption). * **Formula:** Volume of FMH (mL) = (Number of fetal cells / Total cells counted) × Maternal Blood Volume (approx. 5000 mL). * **Dosage:** 300 µg of Anti-D neutralizes **30 mL** of fetal whole blood (or 15 mL of packed RBCs). * **Limitation:** The test is unreliable in mothers with conditions that elevate HbF, such as **Sickle Cell Anemia or Thalassemia**.

Q: The direct Coombs test detects which of the following?

Antibodies in serum. ### Explanation The **Direct Coombs Test (Direct Antiglobulin Test - DAT)** is designed to detect **antibodies (IgG) or complement proteins** that are already bound to the **surface of Red Blood Cells (RBCs)** in vivo. **Why the correct answer is B (Note: Correction to provided key):** There appears to be a discrepancy in the provided key. In medical immunology: * **Direct Coombs Test:** Detects antibodies/complement **on the RBC surface**. * **Indirect Coombs Test:** Detects free, unbound antibodies **in the serum**. If the goal is to identify the mechanism of the *Direct* test, the target is the sensitized RBC. #### Analysis of Options: * **Option B (Correct Mechanism):** In conditions like Autoimmune Hemolytic Anemia (AIHA), antibodies coat the patient's RBCs. Adding "Coombs Reagent" (antihuman globulin) causes these cells to agglutinate, confirming the presence of surface-bound antibodies. * **Option D (Incorrect for Direct):** Detecting antibodies in the serum is the purpose of the **Indirect Coombs Test**, used for prenatal screening (Rh incompatibility) and cross-matching. * **Options A & C (Incorrect):** Coombs tests are designed to detect antibodies (immunoglobulins), not the antigens themselves. #### High-Yield Clinical Pearls for NEET-PG: 1. **Direct Coombs Test Applications:** Hemolytic Disease of the Newborn (HDN), Drug-induced hemolytic anemia, and Transfusion reactions. 2. **Indirect Coombs Test Applications:** Checking maternal blood for anti-Rh antibodies and pre-transfusion compatibility. 3. **Coombs Reagent:** It is **Antihuman Globulin (AHG)**, usually produced by immunizing rabbits against human IgG/complement. 4. **Key Distinction:** Direct = "In the body" (RBCs already coated); Indirect = "In the lab" (Serum tested against reagent RBCs).

Q: A 4-year-old boy has appeared listless during the past week. He exhibits irritability when his arms or legs are touched. In the past 2 days, large ecchymoses have appeared on the right thigh and left shoulder. CBC shows hemoglobin, 9.3 g/dL; hematocrit, 28.7%; MCV, 96 mm3; platelet count, 45,000/mm3; and WBC count, 13,990/mm3. Examination of the peripheral blood smear shows blasts that lack peroxidase positive granules, but contain PAS-positive aggregates and stain positively for deoxynucleotidyl transferase negative (TdT-). Flow cytometry shows the phenotype of blasts to be CD19+, CD3-, and sIg-. Which of the following is the most likely diagnosis?

Acute lymphoblastic leukemia. **Explanation:** The clinical presentation and laboratory findings are classic for **Acute Lymphoblastic Leukemia (ALL)**, the most common malignancy in children. **1. Why the Correct Answer is Right:** * **Clinical Presentation:** The child presents with signs of bone marrow failure: anemia (listlessness), thrombocytopenia (ecchymoses), and bone pain (irritability when touched), which is caused by leukemic infiltration of the periosteum. * **Morphology & Cytochemistry:** The blasts are **PAS-positive** (characteristic of lymphoblasts) and **Peroxidase-negative** (ruling out AML). * **Immunophenotyping:** The presence of **CD19** (a B-cell marker) and the absence of surface immunoglobulin (**sIg-**) confirms a **Pre-B cell lineage**. While most ALL cases are TdT positive, the combination of CD19+, CD3-, and PAS positivity strongly points to ALL over any other option. **2. Why Incorrect Options are Wrong:** * **B. Acute Myelogenous Leukemia (AML):** AML blasts typically show **Myeloperoxidase (MPO)** positivity and may contain Auer rods. They would express myeloid markers (CD13, CD33) rather than CD19. * **C. Chronic Lymphocytic Leukemia (CLL):** CLL is a disease of the elderly (median age >60) and involves mature-appearing lymphocytes, not blasts. * **D. Chronic Myelogenous Leukemia (CML):** CML typically presents with massive splenomegaly and a spectrum of maturing myeloid cells (myelocytes, metamyelocytes) rather than a predominance of PAS-positive blasts. **3. NEET-PG High-Yield Pearls:** * **Most common childhood cancer:** ALL (Peak age: 2–5 years). * **Best Prognostic Factor:** Age 1–10 years and WBC count <50,000/mm³. * **Cytogenetics:** t(12;21) has a **good** prognosis; t(9;22) [Philadelphia chromosome] has a **poor** prognosis in ALL. * **Common Sites of Relapse:** Testes and CNS (due to the blood-brain/blood-testis barrier).

Question 1

The Rumpel Leede test measures what?

Accepted Answer

Capillary fragility

Answer

Bleeding time

Answer

Platelet count

Answer

ESR

Question 2

A 50-year-old woman presents with easy fatigability and a dragging sensation in her abdomen for the past 5 months. Physical examination reveals marked splenomegaly without lymphadenopathy. Laboratory studies show a total WBC count of 250,000/mm3 with a differential count showing 64% segmented neutrophils, 11% band neutrophils, 7% metamyelocytes, 5% myelocytes, 4% myeloblasts, 3% lymphocytes, 2% basophils, 2% eosinophils, and 2% monocytes. A bone marrow biopsy reveals a t(9;22) translocation. Which of the following modes of action of a medication is most likely to result in a complete remission in this patient?

Accepted Answer

Inhibiting tyrosine kinase activity

Answer

Activating cellular caspases

Answer

Antibody binding to EGF receptors

Answer

Delivering normal p53 into cells via viral vectors

Question 3

A 12-year-old girl who underwent a bone marrow transplant as part of therapy for ALL presents with pulmonary complaints and neurologic findings. Lung biopsy reveals a granulomatous vasculitis with associated atypical lymphocytes. Clonality studies reveal a monoclonal B cell population with associated polyclonal T cells. What infectious agent is related to this diagnosis?

Accepted Answer

EBV

Answer

CMV

Answer

HPV

Answer

HHV-8

Question 4

Which of the following is a feature of disseminated intravascular coagulation (DIC)?

Accepted Answer

Reduced plasma fibrinogen

Answer

Normal prothrombin time

Answer

Normal platelet count

Answer

Normal clotting time

Question 5

The Kleihauer Betke test for detecting fetal erythrocytes is based on which principle?

Accepted Answer

HbF is more resistant to acid elution than HbA.

Answer

Adult erythrocytes are larger than fetal erythrocytes.

Answer

HbA has higher oxygen affinity than HbF.

Answer

HbA takes up erythrosin stain less effectively than HbF.

Question 6

The RBC morphology in a peripheral blood smear in thalassemia trait resembles that of which condition?

Accepted Answer

Iron deficiency anemia

Answer

Vitamin B12 deficiency anemia

Answer

Folate deficiency anemia

Answer

Hereditary spherocytosis

Question 7

Cyclin D1/IgH gene rearrangement is associated with which of the following malignancies?

Accepted Answer

Mantle cell lymphoma

Answer

Hairy cell leukemia

Answer

Follicular lymphoma

Answer

Diffuse large B-cell lymphoma

Question 8

Sideroblasts are seen in all conditions except?

Accepted Answer

Thalassemia

Answer

Myelofibrosis

Answer

Alcoholism

Answer

Iron overload

Question 9

The direct Coombs test detects which of the following?

Accepted Answer

Antibodies in serum

Answer

Antigens in serum

Answer

Antibodies on the RBC surface

Answer

Antigens on the RBC surface

Question 10

A 4-year-old boy has appeared listless during the past week. He exhibits irritability when his arms or legs are touched. In the past 2 days, large ecchymoses have appeared on the right thigh and left shoulder. CBC shows hemoglobin, 9.3 g/dL; hematocrit, 28.7%; MCV, 96 mm3; platelet count, 45,000/mm3; and WBC count, 13,990/mm3. Examination of the peripheral blood smear shows blasts that lack peroxidase positive granules, but contain PAS-positive aggregates and stain positively for deoxynucleotidyl transferase negative (TdT-). Flow cytometry shows the phenotype of blasts to be CD19+, CD3-, and sIg-. Which of the following is the most likely diagnosis?

Accepted Answer

Acute lymphoblastic leukemia

Answer

Acute myelogenous leukemia

Answer

Chronic lymphocytic leukemia

Answer

Chronic myelogenous leukemia

Hematopathology — MCQs

Hematopathology — MCQs

On this page

Practice by Chapter

Want unlimited practice?