General Pathology — MCQs

General Pathology Indian Medical PG Practice Questions and MCQs

Question 321: All of the following statements regarding amyloidosis are true, EXCEPT:

A. It is an extracellular deposit.
B. It consists of insoluble polymeric protein fibrils.
C. Amyloid fibrils share a common cross-beta pleated sheet structure.
D. The term 'amyloid' was coined by Rudolf Virchow. (Correct Answer)

Explanation: **Explanation:** The correct answer is **D**. While Rudolf Virchow is famously associated with amyloidosis and popularized the term in 1854 (believing the substance to be starch-like), the term 'amyloid' was actually coined by the German botanist **Matthias Schleiden** in 1838 to describe a starchy constituent of plants [1]. **Analysis of Options:** * **Option A (Incorrect):** Amyloid is strictly an **extracellular** deposit [1]. It accumulates in the interstitium of various tissues, leading to pressure atrophy of adjacent cells [2]. * **Option B (Incorrect):** Biochemically, amyloid consists of **insoluble polymeric protein fibrils** [1]. Approximately 95% of amyloid consists of these fibril proteins, while the remaining 5% consists of the P-component and other glycoproteins [1]. * **Option C (Incorrect):** Regardless of the clinical setting or chemical composition, all amyloid fibrils share a common **cross-beta pleated sheet** secondary structure [2]. This specific conformation is responsible for the characteristic Congo red staining and apple-green birefringence [2]. **High-Yield Clinical Pearls for NEET-PG:** * **Staining:** Congo Red is the gold standard. Under polarized light, it shows **Apple-green birefringence** [2]. * **Morphology:** On H&E stain, it appears as an amorphous, eosinophilic, hyaline extracellular substance. * **Classification:** * **AL (Amyloid Light Chain):** Derived from plasma cells (Primary amyloidosis/Multiple Myeloma) [3]. * **AA (Amyloid Associated):** Derived from SAA protein (Secondary amyloidosis/Chronic inflammation) [4]. * **Transthyretin (TTR):** Seen in Senile Systemic Amyloidosis and Familial Amyloid Polyneuropathies [4]. * **Aβ Amyloid:** Found in Alzheimer’s disease. * **Diagnosis:** Abdominal fat pad aspiration or rectal biopsy are common screening procedures. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Diseases of the Immune System, pp. 264-266. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Diseases of the Immune System, pp. 268-269. [3] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Diseases of the Immune System, pp. 266-267. [4] 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. 136-140.

Question 322: Mitochondrial abnormality is seen in which of the following conditions?

A. Krabbe's disease
B. Fabry disease
C. Fanconi syndrome
D. Wilson's disease (Correct Answer)

Explanation: **Explanation:** **Wilson’s Disease (Hepatolenticular Degeneration)** is the correct answer because it is characterized by a defect in the **ATP7B gene**, leading to impaired biliary copper excretion [2]. The resulting accumulation of free copper in hepatocytes causes oxidative stress via the Fenton reaction. This oxidative damage specifically targets **mitochondria**, leading to structural abnormalities such as mitochondrial swelling, crystalline inclusions, and distorted cristae [2]. These changes are a hallmark of early liver involvement in Wilson’s disease [1]. **Analysis of Incorrect Options:** * **Krabbe’s Disease:** This is a **Lysosomal Storage Disorder (LSD)** caused by a deficiency of galactocerebrosidase. The characteristic finding is the presence of "Globoid cells" (multinucleated macrophages) in the brain, not mitochondrial defects [3]. * **Fabry Disease:** This is an X-linked **LSD** caused by $\alpha$-galactosidase A deficiency. It is characterized by the accumulation of glyc sphingolipids, seen as "zebra bodies" or lamellar inclusions within lysosomes [4]. * **Fanconi Syndrome:** This refers to a generalized dysfunction of the **proximal renal tubules**. While Wilson’s disease can *cause* Fanconi syndrome, the syndrome itself is a clinical manifestation of tubular transport defects rather than a primary mitochondrial pathology. **High-Yield Clinical Pearls for NEET-PG:** * **Kayser-Fleischer (KF) rings:** Copper deposition in the Descemet’s membrane of the cornea [1]. * **Diagnosis:** Low serum ceruloplasmin, increased urinary copper excretion, and increased hepatic copper content (>250 $\mu$g/g dry weight) [1]. * **Treatment:** Copper chelators like **D-penicillamine** or Trientine; Zinc is used to inhibit intestinal copper absorption. * **Histology:** Early stages show microvesicular steatosis; late stages show macronodular cirrhosis. **References:** [1] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Liver And Biliary System Disease, pp. 394-395. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Liver and Gallbladder, pp. 855-856. [3] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Central Nervous System, pp. 1304-1305. [4] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Manifestations Of Central And Peripheral Nervous System Disease, pp. 716-717.

Question 323: Cloudy swelling occurs in which of the following organs, EXCEPT?

A. Kidney
B. Liver
C. Adrenals
D. Lungs (Correct Answer)

Explanation: **Explanation:** **Cloudy swelling**, also known as **hydropic change** or vacuolar degeneration, is the earliest and most common form of reversible cell injury [1]. It occurs due to the failure of energy-dependent Naⁱ-Kⁱ ATPase pumps in the cell membrane, leading to an influx of sodium and water into the cell [1]. **Why Lungs is the Correct Answer:** Cloudy swelling is a phenomenon primarily seen in **parenchymal organs** with high metabolic activity and a high density of mitochondria. The **lungs** consist largely of alveolar spaces and thin epithelial linings (Type I and II pneumocytes) rather than dense metabolic parenchyma. While the lungs can undergo edema, they are not a classic site for the pathological manifestation of "cloudy swelling" as seen in solid visceral organs. **Analysis of Incorrect Options:** * **Kidney (A):** This is the most common site for cloudy swelling, particularly in the cells of the **Proximal Convoluted Tubules (PCT)**, which are highly sensitive to hypoxia and toxins [2]. * **Liver (B):** Hepatocytes are metabolically active and frequently show hydropic change in response to various injuries (e.g., viral hepatitis or toxins) [1]. * **Adrenals (C):** Like the heart and pancreas, the adrenal glands are solid parenchymal organs that can exhibit cloudy swelling during acute stress or toxic injury. **NEET-PG High-Yield Pearls:** * **Mechanism:** Failure of Naⁱ-Kⁱ pump → ↑ Intracellular Naⁱ → Osmotic influx of water → Swelling of cisternae of Endoplasmic Reticulum (ER) [1]. * **Gross Appearance:** The organ appears enlarged, pale, and heavy with rounded margins. * **Microscopy:** The cytoplasm appears granular and "cloudy" due to the presence of small clear vacuoles (distended ER) [1]. * **Reversibility:** It is the first stage of cell injury; if the stimulus is removed, the cell returns to normal. If it persists, it may progress to necrosis [1]. **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, pp. 51-53. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Kidney, pp. 933-934.

Question 324: Dohle bodies are seen in which of the following cells?

A. Neutrophils (Correct Answer)
B. Macrophages
C. Plasma cells
D. Histiocytes

Explanation: **Explanation:** **Dohle bodies** are small, light blue-gray, oval inclusions found in the periphery of the cytoplasm of **neutrophils**. They represent remnants of **rough endoplasmic reticulum (RER)** arranged in parallel stacks. 1. **Why Neutrophils are Correct:** Dohle bodies are classic markers of "toxic changes" in neutrophils. They appear when there is accelerated granulopoiesis (rapid production of white blood cells), typically during severe bacterial infections, burns, trauma, or systemic inflammatory states [1], [2]. They are often seen alongside other toxic features like toxic granulation and cytoplasmic vacuolation. 2. **Why Other Options are Incorrect:** * **Macrophages & Histiocytes:** While these cells are part of the mononuclear phagocyte system and may contain phagocytosed debris or pigments (like hemosiderin), they do not form Dohle bodies. * **Plasma Cells:** These cells are characterized by Russell bodies (intracellular immunoglobulin aggregates) or Mott cells, but not Dohle bodies. **High-Yield Clinical Pearls for NEET-PG:** * **Composition:** Dohle bodies consist of aggregated **ribosomes and RER**. * **May-Hegglin Anomaly:** This is a key differential. It is an autosomal dominant triad of: 1. Large, **Dohle-like bodies** in neutrophils (composed of non-muscle myosin heavy chain IIA). 2. Giant platelets. 3. Thrombocytopenia. * **Differential Diagnosis:** Apart from infections, they can be seen in pregnancy and after the administration of G-CSF (Granulocyte colony-stimulating factor). **References:** [1] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Blood And Bone Marrow Disease, pp. 580-581. [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. 592.

Question 325: Amyloidosis of the kidney may be seen in which of the following conditions, except?

A. Enteric fever (Correct Answer)
B. Ulcerative colitis
C. Suppurative lung disease
D. Hansen's disease

Explanation: **Explanation:** The question tests the understanding of **Secondary (AA) Amyloidosis**, which occurs due to chronic inflammatory or infectious conditions. [1], [2] **Why Enteric Fever is the correct answer:** Secondary amyloidosis is a result of prolonged, chronic inflammation where the liver produces Serum Amyloid-Associated (SAA) protein, which deposits as AA amyloid. [1], [3] **Enteric fever (Typhoid)** is an **acute** infectious disease. Because it does not typically persist for months or years, it does not provide the sustained inflammatory stimulus required for amyloid deposition. **Analysis of Incorrect Options:** * **Ulcerative Colitis:** This is a chronic inflammatory bowel disease (IBD). Persistent inflammation in IBD is a well-recognized cause of systemic AA amyloidosis. * **Suppurative Lung Disease:** Conditions like bronchiectasis, lung abscess, and chronic osteomyelitis are classic "suppurative" (pus-forming) triggers. [1] The long-term release of cytokines (IL-1, IL-6) in these states leads to AA amyloidosis. [2] * **Hansen’s Disease (Leprosy):** Specifically, the lepromatous form of leprosy is a chronic infection frequently associated with secondary amyloidosis, particularly in the kidneys, leading to nephrotic syndrome. **High-Yield Clinical Pearls for NEET-PG:** * **Most common organ involved in systemic amyloidosis:** Kidney (presents as Nephrotic Syndrome). [4] * **Most common site for biopsy:** Rectal mucosa or Abdominal fat pad (easier access). * **Staining:** Congo Red shows **Apple-green birefringence** under polarized light. * **AA Amyloidosis:** Associated with chronic infections (TB, Leprosy, Bronchiectasis) and chronic inflammation (RA, Ankylosing Spondylitis, IBD). [1] * **AL Amyloidosis:** Associated with Plasma Cell Dyscrasias (Multiple Myeloma). [4] **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. 136-140. [2] 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. 195-196. [3] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Diseases of the Immune System, pp. 264-266. [4] 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. 135-136.

Question 326: All of the following statements are true regarding reversible cell injury except?

A. Formation of amorphous densities in the mitochondrial matrix (Correct Answer)
B. Diminished generation of adenosine triphosphate
C. Formation of blebs in the plasma membrane
D. Detachment of ribosomes from the granular endoplasmic reticulum

Explanation: **Explanation:** In cellular pathology, the transition from reversible to irreversible cell injury is defined by specific morphological and functional milestones [1]. **Why Option A is the Correct Answer (The Exception):** The formation of **large, flocculent, amorphous densities** in the mitochondrial matrix is a hallmark of **irreversible cell injury** (necrosis) [1]. These densities represent permanent damage to the mitochondrial inner membrane and the denaturation of proteins. In contrast, reversible injury may show only small, transient mitochondrial swelling or "cloudy swelling." **Analysis of Incorrect Options (Features of Reversible Injury):** * **Option B:** Diminished ATP generation is the initial functional consequence of hypoxia [1]. As long as the cell can switch to anaerobic glycolysis and maintain membrane integrity, the injury remains reversible. * **Option C:** Plasma membrane alterations, such as blebbing, distortion of microvilli, and loosening of intercellular attachments, occur due to cytoskeletal damage but are reversible if oxygenation is restored [1]. * **Option D:** Detachment of ribosomes from the Rough Endoplasmic Reticulum (RER) occurs due to swelling of the cisternae (hydropic change) [1]. This leads to a decrease in protein synthesis but is a classic reversible feature. **NEET-PG High-Yield Pearls:** 1. **The "Point of No Return":** Irreversibility is characterized by two phenomena: the inability to reverse mitochondrial dysfunction and profound disturbances in membrane function (especially the plasma membrane and lysosomal membranes). 2. **Myelin Figures:** These are whorled phospholipid masses derived from damaged cell membranes; they are seen in both reversible and irreversible injury (though more prominent in the latter) [1]. 3. **Earliest Change:** The very first change in hypoxic cell injury is a decrease in oxidative phosphorylation and ATP depletion [1]. 4. **Morphological Hallmarks:** Reversible injury is characterized by **cellular swelling** and **fatty change** [1]. **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, pp. 49-62.

Question 327: Which apoptotic gene is also associated with autophagy?

A. p53
B. BAX
C. BCL-2 (Correct Answer)
D. BID

Explanation: **Explanation:** The correct answer is **BCL-2**. This protein serves as a critical molecular switch that regulates both apoptosis and autophagy, acting as a bridge between these two pathways of cell survival and death. **Why BCL-2 is correct:** BCL-2 is primarily known as an anti-apoptotic protein located on the outer mitochondrial membrane [1]. However, it also functions as an **autophagy inhibitor**. Under normal physiological conditions, BCL-2 binds to **Beclin-1** (a key initiator of autophagy), sequestering it and preventing the formation of the autophagosome. When the cell is stressed or starved, BCL-2 is phosphorylated or released, freeing Beclin-1 to trigger autophagy. Thus, BCL-2 serves as a dual regulator. **Analysis of Incorrect Options:** * **p53 (Option A):** Known as the "Guardian of the Genome," p53 induces apoptosis via the intrinsic pathway (by upregulating BAX/BAK) in response to DNA damage [3]. While it can modulate autophagy indirectly, it is not the primary gene structurally associated with the Beclin-1 complex. * **BAX (Option B):** This is a pro-apoptotic member of the BCL-2 family that forms pores in the mitochondrial membrane to release Cytochrome C [2]. It does not have a direct inhibitory role in autophagy. * **BID (Option C):** A "BH3-only" pro-apoptotic protein that links the extrinsic (Death Receptor) pathway to the intrinsic pathway [4]. It does not regulate autophagy. **NEET-PG High-Yield Pearls:** * **Beclin-1** is the specific protein that BCL-2 binds to inhibit autophagy. * **BH3-only proteins** (like Bim, Bid, Bad) can displace Beclin-1 from BCL-2, thereby **promoting** autophagy. * Autophagy is generally a **pro-survival** mechanism during nutrient deprivation, but "autophagic cell death" can occur if the stress is excessive [1]. **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, pp. 65-67. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Neoplasia, p. 310. [3] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Neoplasia, pp. 303-304. [4] 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. 67.

Question 328: Serum amyloid A protein is associated with which of the following conditions?

A. Alzheimer's disease
B. Chronic inflammatory states (Correct Answer)
C. Chronic renal failure
D. Malignant hypertension

Explanation: Explanation: **Serum Amyloid A (SAA)** is an acute-phase reactant protein synthesized by the liver, primarily under the influence of cytokines like **IL-1 and IL-6** [2]. In **chronic inflammatory states** (such as Rheumatoid Arthritis, Bronchiectasis, or Osteomyelitis), prolonged elevation of SAA leads to its deposition in tissues as **AA amyloid fibrils**, resulting in **Secondary (AA) Amyloidosis** [1]. This is the hallmark of systemic amyloidosis associated with chronic inflammation. **Analysis of Incorrect Options:** * **A. Alzheimer’s disease:** This condition is associated with the deposition of **Aβ (Amyloid Beta)** protein, which is derived from the Amyloid Precursor Protein (APP), not SAA [5]. * **C. Chronic renal failure:** While renal failure is a *consequence* of AA amyloidosis, the specific amyloid associated with long-term hemodialysis in renal failure is **Aβ2-microglobulin** [4]. * **D. Malignant hypertension:** This leads to **hyaline or hyperplastic arteriolosclerosis** and fibrinoid necrosis, but it is not a primary cause of amyloid protein deposition. **High-Yield Pearls for NEET-PG:** * **AA Amyloid:** Associated with chronic inflammation; precursor is SAA (an acute-phase reactant) [3]. * **AL Amyloid:** Associated with Plasma Cell Dyscrasias (e.g., Multiple Myeloma); precursor is Immunoglobulin Light Chain. * **ATTR Amyloid:** Associated with Senile Systemic Amyloidosis and Familial Amyloid Polyneuropathies; precursor is Transthyretin [4]. * **Staining:** All amyloid types show **Apple-green birefringence** under polarized light when stained with **Congo Red**. **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. 136-140. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Diseases of the Immune System, pp. 267-268. [3] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Diseases of the Immune System, pp. 264-266. [4] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Diseases of the Immune System, p. 266. [5] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Diseases of the Immune System, pp. 269-270.

Question 329: White infarct is typically seen in which organ?

A. Lung
B. Intestine
C. Liver (Correct Answer)
D. Ovary

Explanation: Infarcts are classified based on their color and the presence or absence of hemorrhage into **White (Anemic)** and **Red (Hemorrhagic)** infarcts [1]. **Why Liver is the Correct Answer:** White infarcts occur in **solid organs** with **end-arterial circulation** (single blood supply), where the tissue density limits the seepage of blood from adjoining capillary beds into the necrotic area [1]. Common sites include the **Heart, Spleen, and Kidney** [1]. *Note on the Liver:* While the liver has a dual blood supply (Portal vein and Hepatic artery), it is traditionally categorized under organs that develop pale infarcts if a major branch of the hepatic artery is occluded, as the tissue is solid. (Note: In some clinical contexts, liver infarcts are rare due to dual supply, but among the given options, it is the only solid organ typically associated with pale morphology). **Why Other Options are Incorrect:** Red (Hemorrhagic) infarcts occur in tissues with dual circulation, loose stroma, or venous occlusion [1]. * **A. Lung:** Has dual supply (Pulmonary and Bronchial arteries) and loose alveolar tissue; hence, it develops **Red infarcts** [1]. * **B. Intestine:** Characterized by a dual/collateral supply and loose tissue; it typically undergoes **Red infarction** (often due to venous torsion or arterial embolism). * **D. Ovary:** Infarction here is usually due to **venous obstruction** (e.g., Ovarian torsion). When venous outflow is blocked but arterial inflow continues, the tissue becomes engorged and hemorrhagic [1]. **High-Yield NEET-PG Pearls:** * **White Infarct:** Solid organs + End arteries (Heart, Spleen, Kidney) [1]. * **Red Infarct:** Loose tissues (Lung), Dual circulation (Small intestine), Venous occlusion (Ovary/Testis), or Reperfusion injury [1]. * **Morphology:** Most infarcts are **wedge-shaped**, with the apex pointing toward the site of vascular occlusion [1], [2]. * **Histology:** The dominant hallmark of infarction in most organs is **Coagulative Necrosis** (except the Brain, which shows Liquefactive Necrosis). **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Hemodynamic Disorders, Thromboembolic Disease, and Shock, p. 140. [2] 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. 148-149.

Question 330: All of the following are neoplasms found in patients with HIV infection EXCEPT?

A. Kaposi sarcoma
B. Primary lymphoma of brain
C. Invasive cancer of uterine cervix
D. Hepatocellular carcinoma (Correct Answer)

Explanation: The relationship between HIV and neoplasia is primarily defined by the **CDC classification of AIDS-defining illnesses**. HIV-infected patients have a significantly higher risk of developing specific cancers, often mediated by co-infection with oncogenic viruses (like HHV-8, EBV, and HPV) due to profound immunosuppression [1]. **Why Hepatocellular Carcinoma (HCC) is the correct answer:** While HIV patients frequently have co-infections with Hepatitis B (HBV) or Hepatitis C (HCV), **Hepatocellular Carcinoma is NOT classified as an AIDS-defining illness** [4]. Although the incidence of HCC is rising in the HIV population due to increased longevity (thanks to HAART), it does not define the progression to AIDS, unlike the other options listed. **Analysis of Incorrect Options:** * **Kaposi Sarcoma (A):** The most common neoplasm in HIV, caused by **HHV-8**. It is a vascular tumor and a classic AIDS-defining illness [1]. * **Primary CNS Lymphoma (B):** A high-grade B-cell lymphoma strongly associated with **EBV**. It is a major AIDS-defining condition, typically occurring when CD4 counts drop below 50 cells/mm³ [2]. * **Invasive Cervical Cancer (C):** Caused by high-risk **HPV** (16, 18). Because HIV-induced immunosuppression prevents the clearance of HPV, it was added to the CDC list of AIDS-defining illnesses in 1993 [1]. **NEET-PG High-Yield Pearls:** 1. **AIDS-Defining Malignancies:** Kaposi Sarcoma (HHV-8), Non-Hodgkin Lymphoma (Burkitt’s, Immunoblastic, Primary CNS), and Invasive Cervical Cancer [3]. 2. **Non-AIDS Defining Cancers (NADC):** These are increasing in the HAART era; examples include Anal cancer, Hodgkin lymphoma, and Lung cancer. 3. **Most common cancer in HIV:** Kaposi Sarcoma [1]. 4. **Most common cause of death in HIV (modern era):** Non-AIDS defining conditions (including cardiovascular disease and NADCs) [3]. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Diseases of the Immune System, pp. 261-262. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Diseases of the Immune System, pp. 262-263. [3] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Diseases of the Immune System, pp. 260-261. [4] 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. 219-220.

Practice by Chapter

Cell Injury and Cell Death

Practice Questions

Adaptations of Cellular Growth

Practice Questions

Accumulations and Deposits

Practice Questions

Acute and Chronic Inflammation

Practice Questions

Tissue Repair and Wound Healing

Practice Questions

Hemodynamic Disorders

Practice Questions

Genetic Disorders

Practice Questions

Environmental Pathology

Practice Questions

Nutritional Diseases

Practice Questions

Molecular Basis of Disease

Practice Questions

Want unlimited practice?

Get full access to all questions, explanations, and performance tracking.

Start For Free