NEET-PG 2020 - Pathology PYQs Practice Questions

Q: A 30-year-old male presents with swelling around the knee joint. Histopathological examination reveals many giant cells interspersed with mononuclear cells. What is the most likely diagnosis?

Giant cell tumour. ***Giant cell tumour*** - The presence of **giant cells** interspersed with **mononuclear cells** in the histopathological examination is characteristic of giant cell tumors [1], often found around the **knee joint** [1]. - Typically occurs in **young adults** and is associated with **subarticular bone lesions** that cause joint swelling [1]. *Osteosarcoma* - Generally presents with **extensive bone destruction** and **persistent pain**, along with a mass, not primarily giant cell formation. - Commonly involves individuals aged **10-20 years**, making it less likely in a 30-year-old male. *Ewing's sarcoma* - Characterized by **small round blue cells** on histology, often with **more aggressive behavior** and less prominent giant cells. - Typically affects the **pelvis** and **long bones**, rather than directly around the knee joint. *Chondrosarcoma* - Primarily characterized by **cartilage formation** with no prominent giant cells, often leading to a confusing diagnosis in imaging. - Usually occurs in **older adults** and does not typically present with predominant giant cells in histopathology. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Bones, Joints, and Soft Tissue Tumors, pp. 1205-1206. [Practice more Pathology PYQs on OnCourse]

Q: A 35-year-old woman with a long history of dyspnea, chronic cough, sputum production, and wheezing dies of respiratory failure following a bout of lobar pneumonia. She was not a smoker or an alcoholic. Which of the following underlying conditions is most likely associated with the pathologic changes shown in the lung autopsy?

Alpha-1 antitrypsin deficiency. ***Alpha 1 antitrypsin deficiency*** - This condition leads to **accumulation of abnormal protein** in the liver and lungs, resulting in emphysema, which is consistent with chronic cough and dyspnea [1]. - Patients often develop **lung pathology** similar to what is seen in smokers, making it plausible given the patient's background [1]. *Mutation in dynein arms* - This is associated with **primary ciliary dyskinesia**, which presents with recurrent respiratory infections but is not typical in non-smokers or in the context of **dyspnea with chronic cough**. - Usually linked to **situs inversus** and **recurrent infections**, neither of which is highlighted here. *Antibodies against type 4 collagen* - This condition is related to **Goodpasture syndrome**, which typically results in **hemoptysis** and **renal failure**, rather than chronic cough and sputum production. - The predominant involvement in this syndrome does not align with the clinical presentation of **chronic lung disease** noted in this patient. *Cystic fibrosis* - While it causes **chronic respiratory symptoms**, it is usually seen in younger patients and is associated with **pancreatic insufficiency** and **salty sweat**. - The age of the patient and symptom progression does not fit well with a diagnosis of cystic fibrosis. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Lung, pp. 683-684. [Practice more Pathology PYQs on OnCourse]

Q: HBsAg is based on which principle

ELISA. ***ELISA*** - **Enzyme-linked immunosorbent assay (ELISA)** is a widely used laboratory test to detect and quantify antigens (like HBsAg) or antibodies in a sample. - It involves an enzyme-linked antibody that reacts with a substrate to produce a detectable signal, making it highly sensitive and specific for **HBsAg detection**. *Immunochromatography assays* - These are typically **rapid diagnostic tests (RDTs)** that provide quick qualitative results, often used for point-of-care testing. - While they can detect HBsAg, they generally have lower sensitivity and specificity compared to ELISA. *Chemiluminescence* - This is a detection method used in some immunoassays where a chemical reaction emits light, often providing higher sensitivity than colorimetric detection. - While it can be incorporated into HBsAg testing platforms, it is a *detection principle* rather than the primary assay principle like ELISA itself. *Immunofluorescence* - This technique uses **fluorescently labeled antibodies** to visualize antigens in cells or tissues under a fluorescence microscope [1]. - It is used for localization and identification of antigens, but not typically the primary method for routine quantitative HBsAg serology [1]. **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. 259-260. [Practice more Pathology PYQs on OnCourse]

Q: Identify the condition shown in the image.

Peutz-Jeghers syndrome. ***Juvenile polyp*** - Juvenile polyps are commonly found in children and present as **solitary lesions**, usually in the rectum [1]. - They typically appear **smooth**, with a characteristic lobulated surface, emphasizing their benign nature. *Villous adenoma* - Villous adenomas are characterized by **frond-like projections** and have a higher risk of malignant transformation [2]. - These lesions usually occur in adults and are typically larger and more **invasive** compared to juvenile polyps [2]. *Hyperplastic polyp* - Hyperplastic polyps are small, **benign lesions** that result from epithelial overgrowth with a typical **smooth surface** [3]. - They are usually found in the colon and do not present with the distinctive features of juvenile polyps. *Peutz-Jeghers polyp* - Peutz-Jeghers polyps are associated with **Peutz-Jeghers syndrome** and exhibit a **hamartomatous** appearance, often protruding from various gastrointestinal sites [1]. - These polyps are typically more **complex** and can be found in older children and adults, differing significantly from juvenile polyps [1]. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Gastrointestinal Tract, p. 813. [2] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Alimentary System Disease, pp. 371-372. [3] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Gastrointestinal Tract, pp. 811-813. [Practice more Pathology PYQs on OnCourse]

Question 1

A 30-year-old male presents with swelling around the knee joint. Histopathological examination reveals many giant cells interspersed with mononuclear cells. What is the most likely diagnosis?

Accepted Answer

Giant cell tumour

Answer

Osteosarcoma

Answer

Ewing's sarcoma

Answer

Chondrosarcoma

Question 2

A 35-year-old woman with a long history of dyspnea, chronic cough, sputum production, and wheezing dies of respiratory failure following a bout of lobar pneumonia. She was not a smoker or an alcoholic. Which of the following underlying conditions is most likely associated with the pathologic changes shown in the lung autopsy?

Accepted Answer

Alpha-1 antitrypsin deficiency

Answer

Antibodies against type 4 collagen (associated with Goodpasture syndrome)

Answer

Cystic fibrosis (a genetic disorder affecting the lungs)

Answer

Mutation in dynein arms (associated with primary ciliary dyskinesia)

Question 3

HBsAg is based on which principle

Accepted Answer

ELISA

Answer

Chemiluminescence

Answer

Immunofluorescence

Answer

Immunochromatography assays

Question 4

Identify the condition shown in the image.

Accepted Answer

Peutz-Jeghers syndrome

Answer

Villous adenoma

Answer

Hyperplastic polyp

Answer

Juvenile polyp

Question 5

Which of the following factors play a major role in the initiation of thrombus formation?

Accepted Answer

Endothelial injury

Answer

Vasoconstriction

Answer

Coagulation cascade activation

Answer

Platelets activation

Question 6

A 5-year-old child presented with a history of blood in the stools. On examination, there was a polypoid mass in the rectum, a biopsy of which showed as below. The most probable diagnosis is?

Accepted Answer

Juvenile polyp

Answer

Villous adenoma

Answer

Vascular malformation

Answer

Serrated adenoma

Question 7

A 20-year-old man presented with a complaint of a swelling of the wrist for the last two years. Histopathological examination showed spindle-shaped cells and Verocay bodies. What is the diagnosis?

Accepted Answer

Schwannoma

Answer

Lipoma

Answer

Dermoid cyst

Answer

Neurofibroma

Question 8

A 40-year-old person presented with a swelling in the retroperitoneal area. A biopsy from the lesion is as shown below. Molecular analysis demonstrated t(12;16). What is the most probable diagnosis?

Accepted Answer

Myxoid liposarcoma

Answer

Benign lipoma

Answer

Synovial sarcoma

Answer

Pleomorphic sarcoma

Question 9

A 30-year-old woman presents with thyroid swelling. On investigations, her TSH levels are found to be elevated. Postoperative reports showed lymphocytic infiltration and Hurthle cells. A most probable diagnosis is?

Accepted Answer

Hashimoto's thyroiditis

Answer

Graves' disease

Answer

Follicular thyroid carcinoma

Answer

Medullary thyroid carcinoma

Question 10

Loss of foot process is classical in case of?

Accepted Answer

Segmental glomerulosclerosis

Answer

Diabetic nephropathy (later stages)

Answer

Membranous nephropathy

Answer

IgA vasculitis

NEET-PG 2020 — Pathology