Which of the following statements about cross-matching of blood is false?
Medulloblastoma arises exclusively from the cells of
Which of the following testicular tumours is NOT a germ cell tumour?
Which one of the following statements is false about Xanthogranulomatous pyelonephritis in children?
Blebs are associated with which type of cell injury?
Investigation of choice for confirming Henoch Schönlein Purpura is
Fat necrosis is common in:
Which of the following is the most frequent primary malignant tumor of the CNS?
Effect of hypoparathyroidism on bones include -
NEET-PG 2015 - Pathology NEET-PG Practice Questions and MCQs
Question 81: Which of the following statements about cross-matching of blood is false?
- A. Mandatory in all cases except emergency
- B. Involves visible agglutination
- C. Recipient serum is tested against donor packed cells
- D. Donor serum is tested against recipient packed cells (Correct Answer)
Explanation: ***Donor serum is tested against recipient packed cells*** - This statement is **FALSE** and describes a **minor crossmatch**, which is rarely performed in modern transfusion practice. - The minor crossmatch tests donor antibodies against recipient cells, but this is not standard practice because donor plasma is significantly diluted during transfusion, making clinically significant reactions rare. - Modern blood banking focuses on the **major crossmatch** as the critical safety measure. *Recipient serum is tested against donor packed cells* - This statement is **TRUE** and accurately describes the **major crossmatch**, which is the standard and most critical pre-transfusion compatibility test. - The major crossmatch detects antibodies in the recipient's serum that could react with donor red blood cell antigens, preventing potentially fatal hemolytic transfusion reactions. *Mandatory in all cases except emergency* - This statement is **TRUE**. Crossmatching is mandatory for safe transfusion practice. - In life-threatening emergencies where delay could be fatal, uncrossmatched O-negative (universal donor) blood may be given, but this is a rare exception. *Involves visible agglutination* - This statement is **TRUE**. A positive crossmatch indicating incompatibility is identified by **visible agglutination** or **hemolysis**. - These visible reactions occur when recipient antibodies bind to donor red blood cell antigens, signaling that transfusion would cause a severe reaction.
Question 82: Medulloblastoma arises exclusively from the cells of
- A. Immature embryonal cells (Correct Answer)
- B. Ependymal cells
- C. Neurons
- D. Spindle-shaped cells
Explanation: ***Immature embryonal cells*** - **Medulloblastoma** is a malignant **embryonal tumor** of the cerebellum, exclusively arising from primitive neuroectodermal cells. - These tumors are thought to originate from remnants of the **external granular layer** of the cerebellum or other primitive neuroectodermal cells. *Ependymal cells* - Tumors arising from **ependymal cells** are called **ependymomas**, which typically occur within the ventricles of the brain or spinal cord. - Ependymomas have distinct histological features and clinical behavior compared to medulloblastomas. *Neurons* - Tumors primarily composed of neurons or with significant neuronal differentiation include **gangliogliomas** and **central neurocytomas**. - **Medulloblastomas** largely consist of undifferentiated, small round cells with minimal evidence of neuronal maturation. *Spindle-shaped cells* - **Spindle-shaped cells** are characteristic of various tumor types, including some **gliomas** (e.g., pilocytic astrocytoma) or mesenchymal tumors. - While some medulloblastoma variants can show desmoplastic features, the hallmark cell type is a small, round, blue embryonal cell.
Question 83: Which of the following testicular tumours is NOT a germ cell tumour?
- A. Seminoma
- B. Teratoma
- C. Choriocarcinoma
- D. Sertoli cell tumour (Correct Answer)
Explanation: ***Sertoli cell tumour*** - This is a **sex-cord stromal tumour**, not a germ cell tumour, hence it does not arise from germ cells. - Sertoli cell tumours typically present with abnormal hormone levels, but not the classic germ cell tumour markers. *Choriocarcinoma* - This is a **germ cell tumour** that is aggressive and associated with high levels of **beta-hCG** [1][2]. - It derives from the placental tissue and is characterized by **trophoblastic differentiation** [2]. *Seminoma* - A well-known type of **germ cell tumour**, often presenting as a **homogeneous testicular mass** [1]. - It usually manifests with elevated **LDH** and is associated with a more favorable prognosis compared to non-seminomatous germ cell tumours [1]. *Teratoma* - Teratomas are also classified as **germ cell tumours**, containing differentiated tissues like hair, muscle, and bone [1][2]. - They can be **mature** (benign) or **immature** (malignant), and are typically found in younger patients [2][3]. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Lower Urinary Tract and Male Genital System, pp. 979-980. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Lower Urinary Tract and Male Genital System, pp. 982-983. [3] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Diseases Of The Urinary And Male Genital Tracts, pp. 512-513.
Question 84: Which one of the following statements is false about Xanthogranulomatous pyelonephritis in children?
- A. Clinical presentation in children is the same as in adults
- B. Boys are affected more frequently (Correct Answer)
- C. Often affects those younger than 8 years of age
- D. It affects the kidney diffusely more frequently than focally
Explanation: ***Boys are affected more frequently*** - This statement is **false** for xanthogranulomatous pyelonephritis (XGP) in children. XGP typically shows a **female predominance** in children, similar to adults. - The disease is more common in girls due to the higher incidence of **urinary tract infections** and **urinary obstruction** in females. *It affects the kidney diffusely more frequently than focally* - This statement is **true**. XGP predominantly presents as a **diffuse disease** affecting the entire kidney in approximately **80-90% of cases**. - **Focal XGP** (10-20% of cases) can occur and may mimic a renal tumor, but diffuse involvement is the classic and more common presentation in both adults and children [1]. *Clinical presentation in children is the same as in adults* - This statement is **true**. Children with XGP often present with similar symptoms to adults, including **fever**, **flank pain**, **recurrent urinary tract infections**, and a **palpable abdominal mass** [1]. - **Failure to thrive** and **anemia** are also common in pediatric cases, reflecting the chronic nature of the infection. *Often affects those younger than 8 years of age* - This statement is **true**. XGP, when it occurs in children, often presents in the **younger age group**, typically before 8 years of age. - This demographic observation highlights the importance of considering XGP in young children with persistent urinary tract symptoms and imaging abnormalities. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Kidney, pp. 939-940.
Question 85: Blebs are associated with which type of cell injury?
- A. Reversible
- B. Irreversible
- C. Both (Correct Answer)
- D. None of the options
Explanation: ***Correct: Both*** - Blebs (surface membrane protrusions) are associated with **both reversible and irreversible cell injury** - In **reversible injury**: cellular swelling causes cytoskeletal disruption leading to bleb formation; these blebs can resolve if the injurious stimulus is removed - In **irreversible injury**: more extensive and widespread blebbing occurs during apoptosis and necrosis, associated with cell death pathways - The key difference is in the **extent and reversibility**, not the presence or absence of blebs *Incorrect: Reversible* - While blebs do occur in reversible injury, this option is incomplete as it excludes their occurrence in irreversible injury - Blebs are seen in both types of cellular injury, making "reversible" alone an inadequate answer *Incorrect: Irreversible* - While blebs are prominent in irreversible injury (apoptosis and necrosis), they also occur in reversible injury - Standard pathology texts (Robbins) describe bleb formation as a feature of cellular swelling in reversible injury - This option is incomplete as it excludes reversible injury *Incorrect: None of the options* - This is incorrect because blebs are definitively associated with cell injury (both reversible and irreversible types) - Bleb formation is a well-recognized morphological change in cellular pathology
Question 86: Investigation of choice for confirming Henoch Schönlein Purpura is
- A. Serum IgA levels
- B. CRP levels
- C. DTPA
- D. Renal Biopsy (Correct Answer)
Explanation: ***Renal Biopsy*** - **Biopsy (renal or skin)** showing **IgA deposition** is the **confirmatory investigation** for Henoch-Schönlein Purpura (HSP) when histological confirmation is needed [1]. - **Renal biopsy** demonstrates characteristic **IgA-dominant immune deposits** in the mesangium and glomerular capillaries, along with **mesangial proliferation** [1]. - While HSP is primarily a **clinical diagnosis** based on palpable purpura, age < 20 years, abdominal pain, and renal involvement, biopsy provides **definitive confirmation** in atypical presentations or when diagnosis is uncertain. - Immunofluorescence showing **IgA deposition** is the pathognomonic finding [1]. *Serum IgA levels* - Serum IgA levels may be elevated in approximately **50% of HSP cases**, but this is **neither sensitive nor specific**. - **Normal serum IgA does NOT exclude HSP**, making it unreliable as a confirmatory test. - Elevated IgA can occur in many other conditions (IgA nephropathy without vasculitis, liver disease, infections). - Provides only supportive evidence, not confirmation. *CRP levels* - **C-reactive protein (CRP)** is a **non-specific inflammatory marker** that may be elevated in HSP. - Cannot distinguish HSP from other inflammatory or infectious conditions. - Has no role in confirming the diagnosis. *DTPA* - **DTPA scan** assesses **renal perfusion and function** but does not provide diagnostic information about the underlying pathology. - Cannot detect the characteristic **IgA-mediated vasculitis** of HSP. - Not useful for confirming the diagnosis. **References:** [1] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Diseases Of The Urinary And Male Genital Tracts, pp. 526-527.
Question 87: Fat necrosis is common in:
- A. Breast (Correct Answer)
- B. Retroperitoneal fat
- C. Omentum
- D. All of the options
Explanation: ***Breast*** - **Fat necrosis** in the breast is a relatively common benign condition, often resulting from trauma, surgery, or radiation. - It presents as a palpable lump that can mimic malignancy, making its differentiation crucial. *Retroperitoneal fat* - While fat necrosis can occur in the retroperitoneum, particularly in cases of **acute pancreatitis**, it is not considered "common" in this location independently [1]. - The primary tissue affected in pancreatitis is the pancreas itself, with necrosis extending to surrounding fat [1]. *Omentum* - **Omental fat necrosis** can occur but is rare and usually associated with torsion of the omentum or, less commonly, blunt abdominal trauma. - It is not a common site for isolated fat necrosis compared to the breast. *All of the options* - Although fat necrosis can occur in all these locations under specific circumstances, it is not "common" in all of them when considering the typical incidence of the condition. - **Breast fat necrosis** is more frequently encountered in clinical practice than in the omentum or retroperitoneal region. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Pancreas, p. 895.
Question 88: Which of the following is the most frequent primary malignant tumor of the CNS?
- A. Glioblastoma multiforme (Correct Answer)
- B. Oligodendroglioma
- C. Medulloblastoma
- D. Meningioma
Explanation: ***Glioblastoma multiforme*** - **Glioblastoma multiforme (GBM)** is the most common and aggressive primary malignant brain tumor in adults [1]. - It is a **grade IV astrocytoma**, characterized by rapid growth, necrosis, and microvascular proliferation [1]. *Oligodendroglioma* - **Oligodendrogliomas** are primary glial tumors but are less common than GBM. - They typically have a more indolent course than GBM and are often characterized by **IDH mutations** and **1p/19q co-deletion**. *Medulloblastoma* - **Medulloblastoma** is the most common malignant brain tumor in children, but it is rare in adults [2]. - It arises in the **cerebellum** and is a type of embryonal tumor [2]. *Meningioma* - **Meningiomas** are the most common primary brain tumors overall, but they are typically **benign** and originate from the meninges. - While they can be symptomatic due to compression, they are not primarily malignant in the way GBM is. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Central Nervous System, pp. 1308-1310. [2] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Manifestations Of Central And Peripheral Nervous System Disease, pp. 725-726.
Question 89: Effect of hypoparathyroidism on bones include -
- A. Brown tumours
- B. Subperiosteal Resorption of Bone
- C. None of the Above (Correct Answer)
- D. Multiple Cysts in Bone
Explanation: ***None of the Above*** - **Hypoparathyroidism** leads to **decreased parathyroid hormone (PTH)** levels, resulting in **hypocalcemia** and **hyperphosphatemia**. [3] - Unlike hyperparathyroidism, which causes bone resorption, hypoparathyroidism is generally associated with **increased bone density** due to reduced osteoclastic activity. *Brown tumours* - **Brown tumors** are focal lesions caused by **osteoclastic activity** and fibrous tissue replacement in severe **hyperparathyroidism**, which is the opposite of the condition described. [1], [2] - They are a manifestation of **osteitis fibrosa cystica**, a skeletal complication of prolonged excess PTH. [2] *Subperiosteal Resorption of Bone* - **Subperiosteal bone resorption** is a classic radiographic sign of **hyperparathyroidism**, where excessive PTH causes osteoclasts to erode bone, particularly in the phalanges. [1] - This process is driven by **elevated PTH**, which is absent in hypoparathyroidism. *Multiple Cysts in Bone* - **Multiple cysts in bone** (also known as osteitis fibrosa cystica) are characteristic of **severe hyperparathyroidism**, resulting from excessive bone remodeling and fibrous tissue proliferation. [2] - Hypoparathyroidism does not cause bone cysts; instead, it tends to lead to **increased bone mineral density**. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Bones, Joints, and Soft Tissue Tumors, pp. 1194-1195. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Endocrine System, pp. 1105-1106. [3] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Endocrine System, pp. 1106-1107.