NEET-PG 2013 - Pathology Practice Questions

Q: Which of the following is a primary pleural tumor?

Mesothelioma. ***Mesothelioma*** - Mesothelioma is a **primary malignant tumor** of the pleura [1], commonly associated with **asbestos exposure** [2]. - It typically presents with symptoms like **pleuritic chest pain**, dyspnea, and pleural effusion. *Myxoma* - Myxoma is a **benign tumor** primarily found in the **heart**, particularly in the left atrium, not in the pleura. - It does not arise from pleural tissue and lacks the **malignant characteristics** of mesothelioma. *All* - This option suggests that multiple tumors can be primary pleural tumors, which is incorrect as only mesothelioma is recognized as such. - Other tumors like myxoma and lipoma do not originate in the pleura and thus cannot be classified as primary pleural tumors. *Lipoma* - Lipoma is a **benign tumor** made up of adipose tissue [3] and is typically found in *subcutaneous tissue*, not the pleural cavity. - It does not have the malignant potential or association with pleural disease that characterizes mesothelioma. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Lung, pp. 728-729. [2] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Respiratory Tract Disease, pp. 339-340. [3] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Bones, Joints, and Soft Tissue Tumors, p. 1222.

Q: Which of the following changes is NOT seen in atherosclerotic plaque at the time of rupture?

Thick fibrous cap. ***Smooth muscle cell hypertrophy*** - **Smooth muscle cell hypertrophy** is generally associated with stable plaques and does not typically occur in ruptured atherosclerotic plaques [2]. - At rupture, there is **loss of smooth muscle cells** and thinning of the fibrous cap, leading to plaque instability [2]. *Thin fibrosis cap* - A **thin fibrous cap** is a critical feature of vulnerable plaques, making them prone to rupture [2]. - It indicates a **weakened structure** that can no longer withstand the pressure of the underlying lipid core [2]. *Cell debris* - **Cell debris** is often found at the site of rupture, resulting from the necrosis of foam cells and smooth muscle cells. - This indicates **plaque instability** and contributes to the thrombus formation at the rupture site. *Multiple foam cap* - The presence of **multiple foam cells** reflectsing lipid accumulation in the plaque but does not contribute to the phenomenon of plaque rupture directly. - While foam cells are associated with rupture, a **foam cap** is not a recognized pathological finding at the time of rupture. **References:** [1] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Cardiovascular Disease, pp. 271-272. [2] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Cardiovascular Disease, pp. 268-270.

Q: Which of the following conditions is least associated with tumor suppressor genes?

Acute Myeloid Leukemia (AML). ***Multiple endocrine neoplasia*** - This syndrome involves mutations in **proto-oncogenes** like RET rather than tumor suppressor genes. - The condition is mainly characterized by the presence of **multiple endocrine tumors** rather than a failure of tumor suppression. *Retinoblastoma* - Associated with mutations in the **RB1 tumor suppressor gene**, leading to uncontrolled cell proliferation [1] [2]. - Classic example of **loss of function** in a tumor suppressor gene resulting in cancer, specifically in early childhood [1] [2]. *Neurofibromatosis* - Caused by mutations in **NF1** or **NF2 genes**, both of which function as tumor suppressors. - Leads to benign tumors such as **neurofibromas** and other neurogenic tumors due to malfunction in tumor suppression. *Breast cancers* - Often related to mutations in tumor suppressor genes such as **BRCA1** and **BRCA2**, which increase cancer risk [2]. - Implicated in the hereditary form of breast and ovarian cancers due to their roles in DNA repair and cell cycle regulation [2]. **References:** [1] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. (Basic Pathology) introduces the student to key general principles of pathology, both as a medical science and as a clinical activity with a vital role in patient care. Part 2 (Disease Mechanisms) provides fundamental knowledge about the cellular and molecular processes involved in diseases, providing the rationale for their treatment. Part 3 (Systematic Pathology) deals in detail with specific diseases, with emphasis on the clinically important aspects., pp. 227-228. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Neoplasia, pp. 298-302.

Q: Centrilobular necrosis of the liver may be seen with?

CCl4. ***CCl4*** - **Carbon tetrachloride (CCl4)** is the **classic and prototypical** hepatotoxin that causes **centrilobular (zone 3) necrosis**. - The **centrilobular zone (zone 3)** is particularly vulnerable due to its high concentration of **cytochrome P450 enzymes**, which metabolize CCl4 into **toxic free radicals (trichloromethyl radicals)**. - This is the **most characteristic** cause of centrilobular necrosis in toxicology and is the preferred answer for exam purposes. *Ethanol* - **Ethanol** can also cause **centrilobular necrosis** in **alcoholic hepatitis**, as zone 3 is most susceptible to hypoxic injury and oxidative stress. - However, alcoholic liver disease presents with a **spectrum of changes** including steatosis (earliest), hepatitis with ballooning degeneration and Mallory-Denk bodies, and eventual cirrhosis. - While centrilobular necrosis occurs in alcoholic hepatitis, **CCl4 remains the prototype** for pure centrilobular necrosis in exam contexts. *Phosphorus* - **Elemental phosphorus** toxicity causes **periportal (zone 1) necrosis**, which is the opposite pattern from centrilobular necrosis. - It also causes widespread fatty change and hemorrhagic necrosis within the liver. *Arsenic* - **Arsenic poisoning** causes **diffuse/generalized hepatocellular necrosis** and cholestasis, rather than the specific centrilobular pattern. - Chronic exposure is associated with non-cirrhotic portal fibrosis and portal hypertension.

Q: Which of the following is a sign of reversible injury in alcoholic liver disease?

Cytoplasmic vacuole. ***Cytoplasmic vacuole*** - The presence of **cytoplasmic vacuoles** in liver cells indicates fatty change, which is a **reversible injury** in alcoholic liver disease [1][2]. - This injury allows the liver to recover if **alcohol consumption** is ceased, highlighting its reversible nature [1]. *Nuclear karyolysis* - **Nuclear karyolysis** signifies severe cellular damage and necrosis, indicating an irreversible process [2]. - This feature involves the dissolution of the nucleus, which does not align with reversible injury. *Loss of cell membrane* - Loss of the **cell membrane** indicates irreversible damage, leading to cell death rather than a reversible condition [2]. - This change is associated with significant cellular impairment, contrary to the concept of recovery. *Pyknosis* - **Pyknosis**, the condensation of chromatin in the nucleus, suggests irreversible cellular injury and impending necrosis [2]. - It is often a precursor to cell death and is not indicative of reversible damage in liver pathology. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Liver and Gallbladder, pp. 848-850. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Cellular Responses to Stress and Toxic Insults: Adaptation, Injury, and Death, pp. 51-53.

Q: What is the primary mechanism involved in the pathogenesis of acute proliferative glomerulonephritis?

Immune complex mediated. ***Immune complex mediated*** - The pathogenesis of **acute proliferative glomerulonephritis** is primarily caused by **immune complexes** that deposit in the glomeruli, leading to inflammation [1]. - This is typically associated with **post-streptococcal infections**, where the body's immune response generates complexes that affect kidney function [1]. *Cytotoxic T-cell mediated* - This mechanism involves T-cells directly damaging cells, which is not the primary cause of **acute proliferative glomerulonephritis**. - It is more relevant in conditions like **viral infections** or **transplant rejection**, rather than immune complex diseases. *Antibody mediated* - While antibodies play a role in various diseases, acute proliferative glomerulonephritis is primarily mediated by **immune complexes**, not just antibodies alone [1]. - This oes not account for the presence of **complexes formed from antigens**, which is crucial in the pathogenesis [1]. *Cell-mediated (Type IV)* - Type IV hypersensitivity involves delayed-type hypersensitivity, typically seen in **tuberculosis** or **contact dermatitis**, not in acute glomerulonephritis. - The inflammation in this case is due to **immune complexes**, rather than a purely cell-mediated response [1]. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Kidney, pp. 910-916.

Q: Which of the following are examples of trinucleotide repeat mutations?

All of the options. ***All of the options*** - **Fragile X syndrome**, **Friedreich ataxia**, and **Huntington's chorea** are all well-known examples of genetic disorders caused by trinucleotide repeat expansions [1]. - The mutations involve an abnormal increase in the number of repetitions of a specific three-nucleotide sequence in the DNA [1]. *Fragile X syndrome* - This condition is caused by an expansion of the **CGG repeat** in the **FMR1 gene** on the X chromosome [1]. - The expansion leads to hypermethylation and silencing of the gene, impairing the production of fragile X mental retardation protein [1]. *Friedreich ataxia* - This is an autosomal recessive neurodegenerative disorder caused by an expansion of the **GAA repeat** in an intron of the **frataxin gene (FXN)**. - The repeat expansion interferes with transcription, leading to reduced frataxin protein levels. *Huntington's chorea* - This is an autosomal dominant neurodegenerative disorder caused by an expansion of the **CAG repeat** in the **huntingtin gene (HTT)**. - The expanded polyglutamine tract in the huntingtin protein leads to protein misfolding and neuronal damage, particularly in the striatum [1]. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Genetic Disorders, pp. 177-181.

Q: Which mediators are involved in the resolution of inflammation?

Resolvins, protectins, and lipoxins. ***Resolvins, protectins, and lipoxins*** - These are **specialized pro-resolving mediators (SPMs)** derived from omega-3 and omega-6 polyunsaturated fatty acids that actively promote the resolution phase of inflammation. - **Lipoxins** (from arachidonic acid) inhibit neutrophil chemotaxis and promote macrophage-mediated clearance of apoptotic cells. - **Resolvins** (from EPA and DHA) actively terminate inflammatory signals, reduce neutrophil infiltration, and enhance bacterial clearance. - **Protectins** promote resolution by limiting neutrophil recruitment and enhancing clearance of inflammatory debris. - These mediators represent the **endogenous "stop signals"** that actively resolve inflammation rather than simply suppressing it. *IL-10, IL-1 receptor antagonist, and TGF-β* - While these have **anti-inflammatory** effects, they are not classified as primary resolution mediators. - **IL-10** inhibits pro-inflammatory cytokine synthesis and suppresses immune responses (immunosuppressive rather than pro-resolving). - **IL-1 receptor antagonist (IL-1Ra)** blocks IL-1 signaling, preventing inflammation amplification. - **TGF-β** promotes tissue repair and has immunosuppressive functions. - These are **anti-inflammatory mediators** that prevent or dampen inflammation, distinct from specialized pro-resolving mediators that actively orchestrate the resolution process. *TNF-alpha, IL-1, and CRP* - **TNF-alpha** and **IL-1** are classic **pro-inflammatory cytokines** that initiate and amplify inflammation. - **CRP (C-reactive protein)** is an acute-phase reactant and biomarker of inflammation, not a mediator of resolution. *Interferon-gamma and IL-12* - **IFN-γ** and **IL-12** promote **Th1 immune responses** and cellular immunity. - These are pro-inflammatory mediators involved in host defense against intracellular pathogens, not resolution of inflammation.

Q: Which of the following statements is true regarding light microscopy findings in minimal change disease?

No significant changes are seen under light microscopy.. ***No change seen*** - In minimal change disease, **light microscopy** typically shows no significant changes, which is a key characteristic of the condition [1]. - The disease primarily affects the **podocytes** leading to **nephrotic syndrome**, while light microscopy does not reveal any abnormalities [1]. *Loss of foot process seen* - Loss of foot processes is actually observed under **electron microscopy**, not light microscopy. - Light microscopy remains normal, differentiating minimal change disease from other glomerular diseases. *IgA deposits seen* - IgA deposits are associated with **IgA nephropathy**, which is a different condition characterized by mesangial deposition. - Minimal change disease does not have **immunofluorescence** findings, and thus shows no such deposits on light microscopy [1]. *Anti GBM Abs seen* - Anti-GBM antibodies are characteristic of **Goodpasture syndrome**, which presents with significant changes in glomerular structure. - In minimal change disease, there are no **anti-GBM antibodies** or major changes visible under light microscopy. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Kidney, pp. 927-928.

Question 1

Which of the following is a primary pleural tumor?

Accepted Answer

Mesothelioma

Answer

Myxoma

Answer

Lipoma

Answer

None of the options

Question 2

Which of the following changes is NOT seen in atherosclerotic plaque at the time of rupture?

Accepted Answer

Thick fibrous cap

Answer

Inflammatory cell infiltration

Answer

Cell debris

Answer

Smooth muscle cell atrophy

Question 3

Which of the following conditions is least associated with tumor suppressor genes?

Accepted Answer

Acute Myeloid Leukemia (AML)

Answer

Neurofibromatosis

Answer

Retinoblastoma

Answer

Breast cancer

Question 4

Which of the following statements about wound healing is false?

Accepted Answer

Hematomas promote wound healing

Answer

Inhibited by diabetes mellitus (DM)

Answer

Inhibited by foreign body

Answer

Inhibited by infection

Question 5

Centrilobular necrosis of the liver may be seen with?

Accepted Answer

CCl4

Answer

Arsenic

Answer

Ethanol

Answer

Phosphorus

Question 6

Which of the following is a sign of reversible injury in alcoholic liver disease?

Accepted Answer

Cytoplasmic vacuole

Answer

Pyknosis (nuclear shrinkage)

Answer

Loss of cell membrane integrity

Answer

Nuclear karyolysis (nuclear dissolution)

Question 7

What is the primary mechanism involved in the pathogenesis of acute proliferative glomerulonephritis?

Accepted Answer

Immune complex mediated

Answer

T-cell mediated cytotoxicity

Answer

Direct antibody-mediated injury

Answer

Type IV hypersensitivity reaction

Question 8

Which of the following are examples of trinucleotide repeat mutations?

Accepted Answer

All of the options

Answer

Friedreich ataxia

Answer

Fragile X syndrome

Answer

Huntington's chorea

Question 9

Which mediators are involved in the resolution of inflammation?

Accepted Answer

Resolvins, protectins, and lipoxins

Answer

TNF Alfa, IL-1, and CRP

Answer

IL-10, IL-1 receptor antagonist, and TGF-β

Answer

Interferon-gamma and IL-12

Question 10

Which of the following statements is true regarding light microscopy findings in minimal change disease?

Accepted Answer

No significant changes are seen under light microscopy.

Answer

Foot process effacement is observed under electron microscopy, not light microscopy.

Answer

Anti-GBM antibodies are associated with Goodpasture syndrome, not minimal change disease.

Answer

IgA deposits are characteristic of IgA nephropathy, not minimal change disease.

NEET-PG 2013 — Pathology