Which CD markers are typically positive in Chronic Lymphocytic Leukaemia (CLL)?
For testing blood clotting/coagulation parameters, blood is collected in which color-coded vacutainer tube?
What defect is seen in Bernard Soulier syndrome?
Which gene mutation is most commonly associated with Burkitt's lymphoma?
A child diagnosed with von Willebrand disease requires an understanding of the role of von Willebrand factor (vWF). What does von Willebrand factor primarily combine with?
Which blood is transfused in a patient with a Bombay blood group?
What type of cell is shown in the image below?
The following picture shows a lymph node biopsy of a 30-year-old male with cervical lymphadenopathy. The diagnosis is
A 70-year-old male comes with complaints of hip pain. An X-ray of the hip shows lytic lesions and elevated serum calcium levels. Bone marrow plasma cells are 42%, and the cells seen are given in the image below. What is the most likely diagnosis? 
Which of the following is a feature of hemolytic anemia?
Explanation: CD19, CD20, CD23, CD5 [1] - Chronic Lymphocytic Leukemia (CLL) is a malignancy of mature B-lymphocytes, which typically express the pan-B-cell markers CD19 and CD20 (often dimly), along with CD23 [1]. - A hallmark of CLL is the aberrant co-expression of the T-cell marker CD5 [2], which is crucial for differentiating it from other B-cell lymphomas. The peripheral smear in the image shows mature lymphocytes and a characteristic smudge cell, supporting the diagnosis of CLL [1]. CD3, CD5, CD8 - This profile is characteristic of a T-cell malignancy, as CD3 is a pan-T-cell marker and CD8 is a marker for cytotoxic T-cells [2]. - While CD5 is present in CLL, its combination with CD3 and CD8 excludes a B-cell disorder like CLL. CD10, CD19, CD22 - This combination of markers is more suggestive of other B-cell neoplasms like Follicular Lymphoma or Burkitt Lymphoma, which are characteristically CD10 positive [2]. - Typical CLL is negative for CD10 and positive for CD5 and CD23, which are key distinguishing features [1]. CD13, CD33, CD117 - These are markers associated with the myeloid lineage. CD13 and CD33 are classic myeloid antigens often seen in Acute Myeloid Leukemia (AML). - CD117 (c-kit) is a marker for hematopoietic progenitors and is also frequently positive in AML, making this immunophenotype inconsistent with a lymphoid neoplasm. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Diseases of White Blood Cells, Lymph Nodes, Spleen, and Thymus, p. 602. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Diseases of White Blood Cells, Lymph Nodes, Spleen, and Thymus, p. 598.
Explanation: ***Blue*** - The blue-coded vacutainer contains **Sodium Citrate** (3.2% or 3.8%), which is the required anticoagulant for performing coagulation studies, such as **PT** (Prothrombin Time) and **aPTT** (Activated Partial Thromboplastin Time) [1]. - **Sodium Citrate** works by binding and sequestering **calcium ions** (Factor IV), thereby reversibly preventing the coagulation cascade from proceeding until calcium is added back in the lab [1]. *Red* - The Red top tube typically contains **no anticoagulant** (or a clot activator) and is used to obtain **serum** after the blood clots naturally. - It is utilized for chemistry, serology, and blood bank tests, where the natural clotting process is required or coagulation factors are not needed. *Green* - The Green top tube contains **Heparin** (Lithium or Sodium Heparin), which inhibits clotting by augmenting the activity of **antithrombin III** [2]. - Although it provides plasma, it is unsuitable for routine coagulation assays because heparin itself significantly interferes with most coagulation factor tests. *Gray* - The Gray top tube contains **Potassium Oxalate** as an anticoagulant and **Sodium Fluoride** as a preservative. - It is specifically reserved for **glucose** and sometimes **lactate** measurements, as sodium fluoride inhibits enolase, thereby preventing glycolysis (glucose breakdown) by blood cells. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Hemodynamic Disorders, Thromboembolic Disease, and Shock, pp. 128-130. [2] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Blood And Bone Marrow Disease, pp. 583-584.
Explanation: ***Deficiency of GpIb receptors***- **Bernard-Soulier syndrome (BSS)** is an autosomal recessive disorder caused by defective or deficient **Glycoprotein Ib (GpIb)** [1]; this receptor is necessary for platelet adhesion to the subendothelium via **von Willebrand factor (vWF)** [1], [2]. - This defect results in dysfunctional primary **hemostasis**, causing bleeding and characteristic findings like **giant platelets** (macrothrombocytopenia) and mild to severely prolonged **bleeding time**. *Deficiency of GpIIb/IIIa receptor*- Deficiency or dysfunction of the **GpIIb/IIIa receptor** (fibrinogen receptor) causes **Glanzmann thrombasthenia** [1], which impairs platelet aggregation, not initial adhesion. - In Glanzmann thrombasthenia, platelets fail to aggregate in response to most agonists (like ADP or thrombin), but the initial adhesion mediated by GpIb is preserved [1]. *Deficiency of von Willebrand factor*- Deficiency of **von Willebrand factor (vWF)** causes **von Willebrand disease (vWD)**, the most common inherited bleeding disorder. - vWF is the ligand that links GpIb on the platelet to the exposed collagen in the vessel wall [2]; its deficiency is distinct from the receptor deficiency seen in BSS. *Deficiency of ADP receptors*- Deficiency of **ADP receptors** (specifically the P2Y12 receptor) impairs the signal transduction critical for sustained platelet aggregation and granule release [2]. - While affecting primary hemostasis, this congenital receptor deficiency is separate from BSS and is rarely reported; the most common interference with this receptor is therapeutic (**clopidogrel**). **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Red Blood Cell and Bleeding Disorders, pp. 668-669. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Hemodynamic Disorders, Thromboembolic Disease, and Shock, p. 128.
Explanation: ***C-myc*** - Burkitt's lymphoma is characterized by the **t(8;14) translocation** in 80% of cases [1] - This translocation juxtaposes the **C-myc oncogene (chromosome 8)** with the **immunoglobulin heavy chain locus (chromosome 14)** [1] - Results in **constitutive overexpression of C-myc**, driving uncontrolled cell proliferation [1] - This is a **pathognomonic molecular feature** of Burkitt's lymphoma [1] - Variants include t(2;8) and t(8;22) involving immunoglobulin light chain loci [1] *p53* - Tumor suppressor gene involved in many cancers - Not the characteristic mutation defining Burkitt's lymphoma - May be involved in disease progression but not the hallmark feature *Rb* - Retinoblastoma gene, another tumor suppressor - Associated with retinoblastoma and osteosarcoma - Not characteristic of Burkitt's lymphoma *p21* - Cyclin-dependent kinase inhibitor (CDKN1A) - Involved in cell cycle regulation - Not the defining genetic alteration in Burkitt's lymphoma **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Neoplasia, pp. 324-325.
Explanation: ***Glycoprotein Ib***- vWF bridges exposed subendothelial **collagen** to the platelet surface receptor **Glycoprotein Ib (GPIb)**, which is crucial for initiating platelet **adhesion** during primary hemostasis [1], [2].- A deficiency in vWF (von Willebrand disease) or a defect in GPIb (Bernard-Soulier syndrome) impairs this initial binding step [1], [3].*Platelet factor 3*- Platelet factor 3 (PF3) refers to the **phospholipid surface** (cell membrane) of activated platelets, which serves as a necessary platform for the assembly of clotting factors (e.g., the **tenase** and **prothrombinase** complexes) in secondary hemostasis.- Although critical for clotting, PF3 does not represent the primary receptor that vWF binds to on the platelet surface.*ADP*- **Adenosine diphosphate (ADP)** is a chemical mediator released from platelet dense granules that acts to amplify platelet **activation** and promote **aggregation** (by activating P2Y12 and P2Y1 receptors) [1].- ADP is involved after initial adhesion and promotes platelet-platelet interactions (aggregation) via GP IIb/IIIa receptors, not the binding of vWF (adhesion) via GPIb [1], [3].*Prothrombin*- **Prothrombin (Factor II)** is a circulating zymogen that converts to thrombin (Factor IIa) in the common coagulation pathway, leading to the formation of **fibrin** (secondary hemostasis).- While vWF stabilizes **Factor VIII** (another coagulation factor), it does not primarily bind or activate Prothrombin; its main direct platelet interaction is with GPIb [2]. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Hemodynamic Disorders, Thromboembolic Disease, and Shock, p. 128. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Red Blood Cell and Bleeding Disorders, pp. 669-670. [3] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Red Blood Cell and Bleeding Disorders, pp. 668-669.
Explanation: ⚠️ **IMPORTANT CLINICAL NOTE**: Patients with Bombay blood group (Oh phenotype) can **ONLY safely receive Bombay (Oh) blood** from another Bombay donor. **None of the standard ABO blood types listed below are correct or safe** for transfusion. ***Bombay Blood (Oh) - THE ONLY CORRECT ANSWER (Not Listed)*** - Bombay patients lack the **H antigen** due to deficiency of fucosyltransferase enzyme - They produce potent **anti-H, anti-A, and anti-B antibodies** [1] - **Only Bombay (Oh) blood is compatible** - this is the true correct answer - Standard blood banks must maintain rare Bombay donor registries for these patients **Why the listed options are ALL incorrect:** *O negative (Marked as "correct" but clinically WRONG)* - O negative blood **contains the H antigen**, which is present in all standard ABO groups [1] - Transfusing O negative to a Bombay patient causes **severe acute hemolytic transfusion reaction** due to anti-H antibodies - While O negative lacks A and B antigens, the presence of **H antigen makes it incompatible and dangerous** - This is a common misconception that must be avoided in clinical practice *A* - Contains **A antigen and H antigen** - Causes immediate hemolytic reaction from both **anti-A and anti-H antibodies** - Completely incompatible *B* - Contains **B antigen and H antigen** [1] - Causes rapid hemolysis from both **anti-B and anti-H antibodies** - Completely incompatible *AB* - Contains **A antigen, B antigen, and H antigen** - Causes massive hemolytic reaction from all three antibodies - Most incompatible of all standard blood types **Clinical Pearl**: Bombay phenotype is rare (~1 in 10,000 in India). Always maintain autologous blood storage or identify compatible Bombay donors in advance for these patients. **References:** [1] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Blood And Bone Marrow Disease, pp. 627-628.
Explanation: ***Reed Sternberg cell*** - This is a classic **Reed-Sternberg cell**, characterized by its large size, bilobed or multinucleated appearance, and prominent eosinophilic nucleoli, which create a pathognomonic "**owl-eye**" look [1], [2]. - These cells are the neoplastic hallmark of **Hodgkin lymphoma** and are crucial for its diagnosis [2]. *Faggot cell* - Faggot cells are malignant promyelocytes containing numerous **Auer rods** that are bundled together, resembling a bundle of sticks. - They are characteristically seen in **Acute Promyelocytic Leukemia (APL)**, a subtype of AML, and are not depicted in the image. *Mott cells* - Mott cells are plasma cells with cytoplasm packed with **Russell bodies**, which are eosinophilic globules of immunoglobulin, giving the cell a "grape-like" appearance. - They are found in conditions with chronic plasma cell stimulation or plasma cell neoplasms like **multiple myeloma**, but their morphology is distinct from the cell shown. *Sézary-Lutzner cells* - These are malignant T-lymphocytes characterized by a highly convoluted, **cerebriform (brain-like) nucleus**. - They are the hallmark cells of cutaneous T-cell lymphomas, such as **Mycosis Fungoides** and **Sézary syndrome**, and lack the "owl-eye" nucleoli seen in the image. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Diseases of White Blood Cells, Lymph Nodes, Spleen, and Thymus, pp. 614-618. [2] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Diseases Of The Urinary And Male Genital Tracts, pp. 556-557.
Explanation: ***Hodgkin disease*** - The image displays a classic **Reed-Sternberg cell**, a large, often binucleated cell with prominent, eosinophilic nucleoli giving it an "owl's eye" appearance [1]. This finding is pathognomonic for Hodgkin disease [3]. - The clinical presentation of a young adult male with painless cervical lymphadenopathy is a typical initial sign of Hodgkin lymphoma, particularly the nodular sclerosis subtype [1], [2]. *Acute myeloid leukemia (AML)* - AML is a malignancy of myeloid precursors in the bone marrow. A lymph node biopsy would show infiltration by **myeloblasts**, which lack the characteristic binucleation and prominent eosinophilic nucleoli of Reed-Sternberg cells. - Key diagnostic features for AML include the presence of **Auer rods** (cytoplasmic inclusions) in blasts and positive staining for **myeloperoxidase (MPO)**. *Human papillomavirus (HPV)* - HPV is a virus associated with squamous cell carcinomas. Its characteristic cellular finding is the **koilocyte**, a squamous epithelial cell with a wrinkled, hyperchromatic nucleus and a perinuclear halo. - While HPV-related oropharyngeal cancer can metastasize to cervical lymph nodes, the biopsy would show nests of malignant squamous cells, not the distinct cellular morphology seen here. *Chronic lymphocytic leukemia (CLL)* - CLL is a proliferation of small, mature-appearing B-lymphocytes. A lymph node biopsy in CLL would show a diffuse infiltration of these small, monotonous lymphocytes, completely different from the large, atypical cell shown. - The peripheral blood smear is more characteristic for CLL, often showing numerous small lymphocytes and pathognomonic **smudge cells**. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Diseases of White Blood Cells, Lymph Nodes, Spleen, and Thymus, pp. 614-616. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Diseases of White Blood Cells, Lymph Nodes, Spleen, and Thymus, pp. 616-618. [3] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Diseases of White Blood Cells, Lymph Nodes, Spleen, and Thymus, p. 616.
Explanation: ***Multiple myeloma*** - The patient's presentation with bone pain, **lytic bone lesions** on X-ray, **hypercalcemia**, and age >60 years is classic for multiple myeloma [1]. The diagnosis is confirmed by the bone marrow biopsy showing >10% clonal plasma cells (42% in this case) [2]. - The image displays a bone marrow aspirate with extensive infiltration by **plasma cells**, characterized by their eccentric nuclei, abundant basophilic cytoplasm, and a perinuclear halo (hof) [2]. Some binucleated forms are also visible, which can be seen in neoplastic plasmacytosis [2]. *CLL* - Chronic Lymphocytic Leukemia (CLL) is a malignancy of mature B-lymphocytes, not plasma cells. The characteristic finding on a peripheral smear would be **lymphocytosis** with many **smudge cells**. - While bone marrow infiltration occurs, it consists of small, mature-appearing lymphocytes with scant cytoplasm, which is morphologically distinct from the cells shown. *ALL* - Acute Lymphoblastic Leukemia (ALL) is a cancer of immature lymphoid cells called **lymphoblasts**. These cells typically have scant cytoplasm, a high nuclear-to-cytoplasmic ratio, and fine, dispersed chromatin. - ALL is most common in **children**, and while it can cause bone pain, the specific combination of lytic lesions, hypercalcemia, and mature plasma cell morphology is not characteristic. *CML* - Chronic Myeloid Leukemia (CML) is a myeloproliferative disorder involving the excessive production of **granulocytes** (neutrophils, eosinophils, basophils). The bone marrow would show granulocytic hyperplasia. - CML is genetically defined by the presence of the **Philadelphia chromosome** (BCR-ABL1 fusion gene) and clinically presents with marked leukocytosis and often massive splenomegaly, which are not features of this case. **References:** [1] Kumar v, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Diseases of White Blood Cells, Lymph Nodes, Spleen, and Thymus, p. 608. [2] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Blood And Bone Marrow Disease, pp. 616-619.
Explanation: ***Decreased haptoglobin***- Hemolytic anemia involves the rapid breakdown of red blood cells, which releases **free hemoglobin** into the blood plasma. [1]- **Haptoglobin** rapidly binds to this free hemoglobin and is subsequently cleared by the **reticuloendothelial system**, leading to significantly reduced or absent plasma haptoglobin levels. [1]*All of the options given below*- This option is incorrect because both **neutropenia** and **reticulocytopenia** are generally *not* features of uncomplicated hemolytic anemia.*Neutropenia*- **Neutropenia** (low neutrophil count) is not typically associated with hemolytic anemia, which primarily affects the **red cell line**.- It is usually seen in conditions involving bone marrow failure (e.g., **aplastic anemia**) or destruction of white cells, not premature RBC destruction.*Reticulocytopenia*- Uncomplicated hemolytic anemia stimulates the bone marrow to produce new RBCs, resulting in **reticulocytosis** (increased reticulocytes) as a compensatory mechanism. [1]- **Reticulocytopenia** (low reticulocytes) is seen when the bone marrow cannot respond, such as during an **aplastic crisis** (often due to **Parvovirus B19** infection) or when the anemia is caused by true bone marrow failure. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Red Blood Cell and Bleeding Disorders, pp. 638-640.
Anemias: Classification and Approach
Practice Questions
Hemolytic Anemias
Practice Questions
Myeloproliferative Neoplasms
Practice Questions
Myelodysplastic Syndromes
Practice Questions
Acute Leukemias
Practice Questions
Chronic Leukemias
Practice Questions
Lymphomas and Lymphoid Neoplasms
Practice Questions
Plasma Cell Disorders
Practice Questions
Bleeding Disorders
Practice Questions
Thrombotic Disorders
Practice Questions
Get full access to all questions, explanations, and performance tracking.
Start For Free