NEET-PG 2015 - Pathology Practice Questions

Q: Caseating necrosis most commonly occurs in

Lung. ***lung*** - **Caseating necrosis** is classically associated with **tuberculosis**, which primarily affects the lungs [1]. - It is characterized by the presence of **granulomatous inflammation**, often leading to the formation of cavities in pulmonary tissue. *Brain* - While certain infections can lead to necrosis in the brain, they typically do not present as **caseating necrosis**, which is specific to certain conditions like tuberculosis. - The brain may show **liquefactive necrosis** or other types of necrosis, rather than **caseation**. *liver* - The liver usually shows **macrovesicular steatosis** or **apoptosis** in conditions like hepatitis, not caseating necrosis. - **Granulomatous hepatitis** can occur, but it does not typically result in **caseating** type necrosis associated with lung pathology. *kidney* - The kidneys can experience necrosis from various causes, but caseating necrosis is not typical; they are more often involved in **focal segmental glomerulosclerosis** or **acute tubular necrosis**. - Chronic kidney conditions may involve granulomas, but they usually are not characterized by **caseation** similar to that seen in pulmonary tissue. **References:** [1] 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, p. 55.

Q: Liquefactive necrosis is seen in:

Brain. ***Brain*** - **Liquefactive necrosis** primarily occurs in the **brain** due to the high fat content and the process of enzymatic degradation of tissue after a cerebral infarction [1]. - This type of necrosis results in the transformation of tissue into a liquid viscous mass, often observed during **abscess formation** or ischemic damage [1]. *Spleen* - Commonly undergoes **caseous necrosis** in conditions like tuberculosis, not liquefactive necrosis. - **Hematopoietic tissue** destruction can occur, but it generally results in a differing necrotic pattern. *Heart* - Typically exhibits **coagulative necrosis** following myocardial infarction due to ischemic damage. - This results in the preservation of tissue architecture, differing from the liquid consistency seen in liquefactive necrosis. *Lungs* - Usually experiences **caseous necrosis** in the context of pulmonary tuberculosis, or **hemorrhagic necrosis** after certain infections, but not liquefactive necrosis. - The predominant necrotic process in the lungs is often related to **inflammatory responses** rather than liquefactive changes. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Central Nervous System, pp. 1268-1269.

Q: What type of necrosis is associated with Myocardial Infarction (MI)?

Coagulative necrosis. ***Coagulative necrosis*** - Myocardial infarction (MI) typically results in **coagulative necrosis**, characterized by the preservation of the outline of the tissue despite cellular death [1]. - It is often associated with **ischemia**, where blood supply is obstructed, leading to cell death while maintaining tissue architecture for a time [1]. *Fat necrosis* - Fat necrosis is typically associated with **trauma** or **inflammation** in fat tissue, often seen in conditions like pancreatitis. - It is characterized by the presence of **necrotic adipocytes** and does not involve the myocardium directly or predominantly. *Caseous necrosis* - Caseous necrosis is often associated with **tuberculosis** infections, where tissue becomes crumbly and cheese-like. - It is not relevant to myocardial infarction, which does not present with the classical **granulomatous inflammation** of caseous necrosis. *Liquefactive necrosis* - Liquefactive necrosis typically occurs in conditions such as **brain infarcts** or bacterial infections leading to **pus formation**, not in MI. - It involves the transformation of tissue into a **liquid viscous mass**, which is not characteristic of myocardial tissue affected by infarction. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Heart, p. 552.

Q: First mediator of inflammation to be released is

Histamine. ***Histamine*** - Histamine is the **first mediator of inflammation released** by mast cells and basophils during an allergic or inflammatory response [1][3]. - It promotes **vasodilation** and increased vascular permeability, leading to typical symptoms of inflammation [1][2]. *PAF* - Platelet-activating factor (PAF) is released later in the inflammatory process and is primarily involved in **amplifying** the response rather than initiating it. - It plays a role in **platelet aggregation** and acting on vascular smooth muscle but is not the first released mediator. *Nitric oxide* - Nitric oxide is produced by endothelial cells and plays a role in **vascular relaxation and inflammation**, but it is not among the first mediators released. - It is involved in more **regulatory functions** in the inflammatory response rather than the initial trigger. *IL-1* - Interleukin-1 (IL-1) is a cytokine that is important for the **inflammatory response**, but it is produced after the initial release of mediators like histamine [2]. - It is primarily secreted by **activated macrophages** and contributes to the **amplification** of the immune response [2]. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Inflammation and Repair, pp. 84-85. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Inflammation and Repair, p. 101. [3] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Inflammation and Repair, pp. 93-94.

Q: Which of the following is an example of an antiapoptotic gene?

FLIP. ***FLIP*** - **FLIP** is an **antiapoptotic gene** that inhibits the activation of caspase-8, thereby blocking the extrinsic apoptotic pathway. - It acts as an **FLICE-inhibitory protein**, preventing the formation of the death-inducing signaling complex (DISC) or its downstream activation. *P53* - **P53** is a **tumor suppressor gene** that promotes apoptosis in response to DNA damage or cellular stress. - It is a **pro-apoptotic gene**, orchestrating cell cycle arrest and apoptosis to prevent the propagation of damaged cells. *BAX* - **BAX** is a **pro-apoptotic gene** belonging to the Bcl-2 family, which promotes the release of cytochrome c from mitochondria. - This release initiates the **intrinsic apoptotic pathway**, leading to caspase activation and cell death. *BIM* - **BIM** is a **pro-apoptotic gene** of the Bcl-2 family, acting as a sensitizer for apoptosis by binding to and inhibiting anti-apoptotic Bcl-2 family proteins. - Its activation leads to the **neutralization of survival factors**, thereby promoting mitochondrial outer membrane permeabilization and apoptosis.

Q: Rolling of leucocytes on endothelial cells is mediated by which of the following?

P-selectin. ***P- selectin*** - P-selectin is a **cell adhesion molecule** crucial for the **rolling** of leukocytes on endothelial cells during the inflammatory response [1]. - It is expressed on activated endothelial cells and binds to **sialylated carbohydrates** on leukocytes, facilitating their transient adhesion [1]. *IL-8* - IL-8 is a **chemokine** that primarily acts as a chemotactic factor for neutrophils rather than mediating rolling on endothelium. - While it attracts leukocytes to sites of inflammation, it does not play a role in the initial contact or rolling process. *ICAM-1* - ICAM-1 is an **intercellular adhesion molecule** that facilitates **firm adhesion** rather than rolling of leukocytes. - It primarily interacts with **integrins** on leukocytes to stabilize their adhesion after rolling has occurred. *(3, integrin* - Integrins play a significant role in **firm adhesion** and not the rolling phase, interacting with receptors like ICAM-1. - The binding of integrins to their ligands occurs after leukocytes have initially rolled on the endothelium. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Inflammation and Repair, p. 87.

Q: Diabetic foot is associated with following type of gangrene -

Wet gangrene. ***Wet gangrene*** - Diabetic foot commonly leads to **ischemia** and **infection** [1], resulting in wet gangrene characterized by moist, necrotic tissue. - This type of gangrene is associated with **rapid progression** and can result in systemic toxicity, making prompt treatment essential. *Fournier's gangrene* - This type of gangrene specifically affects the **perineal** region and is not directly associated with diabetic foot. - It usually arises from infections related to **perineal trauma** or surgical procedures. *Gas gangrene* - Caused by **Clostridium** species and typically follows a traumatic injury or surgical procedure, not specifically related to diabetes. - Presents with **crepitus** and rapid systemic symptoms, different from the chronic nature of diabetic ulcers. *Dry gangrene* - Associated with **chronic ischemia** and necrosis, it occurs in conditions like peripheral arterial disease, not primarily with infections seen in diabetic foot [1]. - It usually develops gradually without the sudden onset of symptoms characteristic of wet gangrene.

Question 1

Caseating necrosis most commonly occurs in

Accepted Answer

Lung

Answer

Brain

Answer

Liver

Answer

Kidney

Question 2

Liquefactive necrosis is seen in:

Accepted Answer

Brain

Answer

Cardiac tissue

Answer

Pulmonary tissue

Answer

Splenic tissue

Question 3

Which type of necrosis is most commonly associated with the spread of infection?

Accepted Answer

Liquefactive necrosis

Answer

Fibrinoid necrosis

Answer

Fat necrosis

Answer

Coagulative necrosis

Question 4

What type of necrosis is associated with Myocardial Infarction (MI)?

Accepted Answer

Coagulative necrosis

Answer

Liquefactive necrosis

Answer

Caseous necrosis

Answer

Fat necrosis

Question 5

First mediator of inflammation to be released is

Accepted Answer

Histamine

Answer

Nitric oxide

Answer

PAF

Answer

IL-1

Question 6

Which of the following is an example of an antiapoptotic gene?

Accepted Answer

FLIP

Answer

P53

Answer

BAX

Answer

BIM

Question 7

Which of the following is not considered an example of excess tissue growth?

Accepted Answer

Granulation tissue

Answer

Neoplasia

Answer

Hyperplasia

Answer

Fibrosis

Question 8

Rolling of leucocytes on endothelial cells is mediated by which of the following?

Accepted Answer

P-selectin

Answer

ICAM-1

Answer

Integrin

Answer

IL-8

Question 9

Which substance plays a significant role in the tumor metastasis cascade?

Accepted Answer

MMP-2 (Matrix Metalloproteinase-2)

Answer

TNF-alpha

Answer

CD99

Answer

NM23

Question 10

Diabetic foot is associated with following type of gangrene -

Accepted Answer

Wet gangrene

Answer

Dry gangrene

Answer

Gas gangrene

Answer

Fournier's gangrene

NEET-PG 2015 — Pathology