NEET-PG 2019 - Pathology Practice Questions

Q: Cholesterol gallstones are made up of:-

Crystalline cholesterol monohydrate. ***Crystalline cholesterol monohydrate*** - **Cholesterol gallstones** primarily consist of **crystalline cholesterol monohydrate**, which forms when the bile becomes supersaturated with cholesterol [1]. - The **crystallization** of cholesterol leads to the formation of visible stones within the gallbladder. *Amorphous cholesterol dihydrate* - This form of cholesterol is not typically found as the primary component of **gallstones**. - **Amorphous** structures lack a defined crystalline lattice and are less stable for forming solid stones. *Amorphous cholesterol monohydrate* - While **cholesterol monohydrate** is the core component, it is in a **crystalline** rather than amorphous state in gallstones [1]. - **Amorphous** forms are generally transient intermediates and do not constitute the bulk of the stones. *Crystalline cholesterol dihydrate* - **Dihydrate** forms of cholesterol are not the main constituent of gallstones; the **monohydrate** form is the predominant type [1]. - The specific hydration state of **cholesterol monohydrate** makes it the primary compound found in the solid, crystalline structure of gallstones [1]. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Liver and Gallbladder, p. 882.

Q: McCallum patches/plaques are usually seen in which chamber of the heart?

Left atrium. Left atrium - **McCallum patches** are typically found in the **left atrium**, predominantly on the left atrial endocardium [1]. - They are associated with the regurgitant jet of **rheumatic mitral valve disease**, leading to endocardial thickening and fibrosis [1]. Right atrium - While rheumatic heart disease can affect the right side of the heart, particularly the tricuspid valve, **McCallum patches have a specific association with the left atrium** due to mitral valve involvement [1]. - Endocardial changes in the right atrium are less commonly described as McCallum patches. Left ventricle - The left ventricle is primarily a pumping chamber; while it can undergo hypertrophy or dilation in rheumatic heart disease, **McCallum patches are specific endocardial lesions of the atrium** [1]. - **Jet lesions** can occur in the ventricle due to aortic regurgitation, but these are distinct from atrial McCallum patches. Right ventricle - The right ventricle is also a pumping chamber, and endocardial changes here are not typically referred to as McCallum patches. - Rheumatic involvement of the tricuspid valve can cause right heart strain, but **McCallum patches are characteristic of left atrial involvement** [1]. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Heart, p. 566.

Q: False statement about Barrett esophagus is:

Columnar to squamous metaplasia. ***Columnar to squamous metaplasia*** - Barrett esophagus is characterized by the replacement of the normal **squamous epithelium** of the distal esophagus with **columnar epithelium** [1]. - Therefore, the statement "Columnar to squamous metaplasia" is incorrect as it describes the opposite process, making it the false statement. *Chronic GERD is the predisposing factor* - **Chronic gastroesophageal reflux disease (GERD)** causes repeated exposure of the esophageal lining to stomach acid, leading to cellular damage [1][2]. - This chronic irritation is the primary risk factor for the development of Barrett esophagus [1]. *May lead to malignancy after few years* - Barrett esophagus is a significant risk factor for the development of **esophageal adenocarcinoma** [1][3]. - The metaplastic columnar epithelium can undergo further dysplastic changes, which can progress to invasive cancer over time [2]. *Goblet cells seen on histology* - The distinctive histological feature of Barrett esophagus is the presence of **intestinal metaplasia**, which includes the identification of **goblet cells** within the columnar epithelium [1]. - These goblet cells are a key diagnostic marker for Barrett esophagus [1]. **References:** [1] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Alimentary System Disease, pp. 348-349. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Gastrointestinal Tract, pp. 764-765. [3] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Gastrointestinal Tract, pp. 765-766.

Q: Glanzmann thrombasthenia is due to defect in:-

Gp IIb/IIIa. ***Gp IIb/IIIa*** - Glanzmann thrombasthenia is a **rare, inherited bleeding disorder** characterized by a defect or deficiency in the **glycoprotein IIb/IIIa (Gp IIb/IIIa) complex** on the platelet surface [1]. - This complex is crucial for platelet aggregation as it acts as the receptor for **fibrinogen**, which links activated platelets together [1]. *Gp VI* - **Glycoprotein VI (Gp VI)** is a collagen receptor on platelets, important for initial **platelet adhesion and activation** at sites of vascular injury. - Defects in Gp VI are associated with milder bleeding disorders, not Glanzmann thrombasthenia. *Thromboxane A2* - **Thromboxane A2 (TXA2)** is a potent **vasoconstrictor** and **platelet aggregator** synthesized by platelets. - Disorders in TXA2 synthesis or response, such as aspirin-induced platelet dysfunction, cause bleeding but are biochemically distinct from Glanzmann thrombasthenia. *Gp Ia/IIa* - The **glycoprotein Ia/IIa (Gp Ia/IIa) complex** (also known as integrin ̡2̢1) is another **collagen receptor** on platelets, mediating platelet adhesion to collagen. - Defects in Gp Ia/IIa lead to a different type of mild bleeding disorder, affecting initial adhesion rather than aggregation. **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.

Q: Which of the following features distinguishes Crohn's disease from Ulcerative colitis?

Transmural involvement. ***Transmural involvement*** - **Crohn's disease** is characterized by **transmural inflammation**, meaning the inflammation extends through all layers of the bowel wall [1]. This deep inflammation can lead to complications like **fistulas**, **strictures**, and **abscesses** [1], [3]. - In contrast, **Ulcerative colitis** typically involves inflammation limited to the **mucosa and submucosa** [4]. *Lymphocyte infiltrate* - Both Crohn's disease and Ulcerative colitis involve a **lymphocyte infiltrate** as part of the chronic inflammatory process [2]. This feature is not specific enough to differentiate between the two conditions. - The presence of lymphocytes, plasma cells, and other inflammatory cells is common in any chronic inflammatory bowel condition. *Mucosal edema* - **Mucosal edema** can be found in both Crohn's disease and Ulcerative colitis due to the inflammatory process. It is a general sign of inflammation rather than a specific differentiating feature. *Pseudopolyps* - **Pseudopolyps** are characteristic of **Ulcerative colitis**, forming as islands of regenerating mucosa in areas of severe inflammation and ulceration [4]. - While they can occasionally be seen in chronic Crohn's disease, they are much more common and prominent in Ulcerative colitis, representing a reparative process rather than primary disease activity. **References:** [1] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Alimentary System Disease, pp. 365-366. [2] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Alimentary System Disease, pp. 366-367. [3] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Gastrointestinal Tract, pp. 806-807. [4] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Gastrointestinal Tract, p. 809.

Q: Hemolysis is predominantly intravascular in which of the following conditions?

Paroxysmal nocturnal hemoglobinuria. ***Paroxysmal nocturnal hemoglobinuria*** - **PNH** is characterized by a defect in the **PIG-A gene**, leading to a deficiency of **GPI-anchored proteins** like CD55 and CD59 on red blood cells [1]. - This deficiency makes the red blood cells susceptible to complement-mediated lysis, predominantly occurring **intravascularly** [1]. *Warm autoimmune hemolytic anemia* - This condition involves **IgG autoantibodies** binding to red blood cells, which are then primarily removed by **macrophages in the spleen** and liver (extravascular hemolysis) [2]. - The presence of **spherocytes** and a positive direct **antiglobulin test (DAT)** are characteristic [2]. *Cold autoimmune hemolytic anemia* - Involves **IgM autoantibodies** that bind to red blood cells at colder temperatures, often causing agglutination in the peripheral circulation. - While some complement activation and lysis can occur intravascularly, the primary mechanism involves **macrophages in the liver** clearing antibody-coated red cells (extravascular), or red cell destruction in the cooler acral areas. *Spherocytosis* - This is a condition of abnormal red blood cell shape due to defects in **cytoskeletal proteins** (e.g., spectrin, ankyrin), making them less deformable. - These rigid spherocytes are primarily trapped and destroyed by the **phagocytic cells in the spleen**, indicating an **extravascular hemolytic process** [2]. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Red Blood Cell and Bleeding Disorders, pp. 650-651. [2] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Blood And Bone Marrow Disease, pp. 602-603.

Q: Bellini duct cancer is seen in which of the following?

Kidney. ***Kidney*** - Bellini duct carcinoma is a **rare and aggressive subtype of renal cell carcinoma (RCC)**, originating from the collecting ducts of Bellini in the kidney. [1] - It accounts for a very small percentage of all RCCs and is characterized by a **poor prognosis**. *Liver* - The liver is affected by primary cancers like **hepatocellular carcinoma** and **cholangiocarcinoma**, or by metastatic disease, none of which arise from Bellini ducts. - Bellini ducts are structures **exclusive to the kidney**, not found in the liver. *Spleen* - Primary cancers of the spleen are **extremely rare**, with most malignant lesions being **lymphomas** or metastases. [2] - The spleen is a **lymphoid organ** and does not contain Bellini ducts. *Heart* - Primary cardiac tumors are uncommon, with the majority being **benign myxomas**. Malignant tumors include **sarcomas**. - The heart's anatomy is distinct and **does not contain any structures analogous to Bellini ducts**. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Kidney, pp. 959-961. [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. 605-606.

Q: Which type of necrosis is characterized by deposition of immune complexes and fibrin in the walls of blood vessels?

Fibrinoid necrosis. ***Fibrinoid necrosis*** - This type of necrosis is classically associated with **immune-mediated vascular damage**, where antigen-antibody complexes are deposited in arterial walls [2]. - The microscopic appearance is characterized by bright pink, amorphous material composed of **fibrin and immune complexes**, giving a fibrin-like staining pattern [1]. *Liquefactive necrosis* - Characterized by the **dissolution of dead cells into a viscous liquid mass**, often seen in bacterial infections or brain infarcts. - The necrotic tissue is replaced by inflammatory cells and fluid, rather than immune complex deposits. *Coagulative necrosis* - Occurs due to **ischemia**, leading to protein denaturation and preservation of cell outlines for a period. - It does not involve the deposition of immune complexes or fibrin in vessel walls. *Caseous necrosis* - A form of coagulative necrosis associated with **tuberculosis**, characterized by a friable, "cheese-like" appearance. - It primarily involves granulomatous inflammation and macrophage accumulation, not immune complex deposition in blood vessels. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Diseases of Infancy and Childhood, pp. 514-518. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Diseases of the Immune System, pp. 214-242.

Question 1

Cholesterol gallstones are made up of:-

Accepted Answer

Crystalline cholesterol monohydrate

Answer

Amorphous cholesterol dihydrate

Answer

Amorphous cholesterol monohydrate

Answer

Crystalline cholesterol dihydrate

Question 2

McCallum patches/plaques are usually seen in which chamber of the heart?

Accepted Answer

Left atrium

Answer

Right atrium

Answer

Left ventricle

Answer

Right ventricle

Question 3

False statement about Barrett esophagus is:

Accepted Answer

Columnar to squamous metaplasia

Answer

Chronic GERD is the predisposing factor

Answer

May lead to malignancy after few years

Answer

Goblet cells seen on histology

Question 4

Glanzmann thrombasthenia is due to defect in:-

Accepted Answer

Gp IIb/IIIa

Answer

Gp VI

Answer

Thromboxane A2

Answer

Gp Ia/IIa

Question 5

Which of the following features distinguishes Crohn's disease from Ulcerative colitis?

Accepted Answer

Transmural involvement

Answer

Lymphocyte infiltrate

Answer

Mucosal edema

Answer

Pseudopolyps

Question 6

Hemolysis is predominantly intravascular in which of the following conditions?

Accepted Answer

Paroxysmal nocturnal hemoglobinuria

Answer

Warm autoimmune hemolytic anemia

Answer

Cold autoimmune hemolytic anemia

Answer

Spherocytosis

Question 7

Which of the following is positive in Follicular lymphoma?

Accepted Answer

Bcl-2 protein

Answer

Cyclin D1 (Bcl-1)

Answer

Bcl-10 signaling protein

Answer

Bcl-6 transcription factor

Question 8

Bellini duct cancer is seen in which of the following?

Accepted Answer

Kidney

Answer

Liver

Answer

Spleen

Answer

Heart

Question 9

Which type of necrosis is characterized by deposition of immune complexes and fibrin in the walls of blood vessels?

Accepted Answer

Fibrinoid necrosis

Answer

Liquefactive necrosis

Answer

Coagulative necrosis

Answer

Caseous necrosis

NEET-PG 2019 — Pathology