INI-CET 2018 - Pathology PYQs Practice Questions

Q: Immunofluorescence staining pattern from a kidney biopsy from a 35-year-old patient presenting with proteinuria has been shown below. What is the most probable cause?

Lupus Nephritis. ***Lupus Nephritis*** - The image illustrates a **"full-house" immunofluorescence pattern**, characterized by positive staining for multiple immunoglobulins (IgG, IgM, IgA) and complement components (C3, C1q) [1]. - This "full-house" pattern is highly characteristic of **Lupus Nephritis**, reflecting the deposition of immune complexes containing these components in the glomeruli [1]. *FSGS* - Focal segmental glomerulosclerosis (FSGS) typically shows **minimal or no immune complex deposition** on immunofluorescence [2]. - If any staining is present, it is usually focal and segmental, primarily for IgM and C3 in sclerotic lesions, and does not exhibit a widespread "full-house" pattern [2]. *Goodpasture syndrome* - Goodpasture syndrome is characterized by a **linear pattern of IgG deposition** along the glomerular basement membrane (GBM). - This linear pattern is distinctly different from the granular, widespread, and multi-component "full-house" staining seen in the image. *PSGN* - Post-streptococcal glomerulonephritis (PSGN) typically presents with a **"lumpy-bumpy" or granular pattern** due to subepithelial immune deposits [3]. - While it involves C3 and IgG, it usually does not show the full spectrum of IgA, IgM, and C1q deposition as prominently or diffusely as seen in the "full-house" pattern of Lupus Nephritis [3]. **References:** [1] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Diseases Of The Urinary And Male Genital Tracts, pp. 532-533. [2] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Diseases Of The Urinary And Male Genital Tracts, pp. 530-531. [3] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Kidney, pp. 915-916. [Practice more Pathology PYQs on OnCourse]

Q: A macrophage engulfs different cells as shown in the image. This is known as?

Emperipolesis. ***Emperipolesis*** - The image shows a large cell (likely a macrophage or megakaryocyte) containing **intact various blood cells** within its cytoplasm without signs of degeneration. - **Emperipolesis** is specifically defined as the **active penetration of one cell by another**, where both the engulfed and engulfing cells remain viable. *Phagocytosis* - **Phagocytosis** involves the ingestion and subsequent **destruction or degradation** of foreign particles, microorganisms, or cellular debris. - The cells within the macrophage in the image appear **morphologically intact** and not in a state of degradation. *Killing* - **Killing** implies the process by which a cell actively destroys another cell, often through mechanisms like **apoptosis or necrosis**. - There are **no morphological features** in the image to suggest that the engulfed cells are being actively killed or are undergoing degeneration. *Cytotoxicity* - **Cytotoxicity** refers to the ability of certain immune cells (e.g., cytotoxic T lymphocytes, NK cells) to **kill target cells**. - This process usually involves specific recognition and induction of target cell death, which is not what is depicted by the presence of intact cells within another cell. [Practice more Pathology PYQs on OnCourse]

Q: A patient presents with intermittent fever, no weight loss and enlarged retroperitoneal lymph nodes. Peripheral smear is normal. Gross sample and its histopathology slide is shown below. Comment on the diagnosis.

Castleman disease. ***Castleman disease*** - The image shows **"lollipop lesions"** or **"onion-skinning"** of follicles with **regressed germinal centers** and prominent mantle zones, characteristic of the hyaline-vascular variant of Castleman disease. - Clinical features like **intermittent fever** and **enlarged retroperitoneal lymph nodes** with **no weight loss** can be seen in Castleman disease, particularly the unicentric type. *Non-Hodgkin's lymphoma* - This would typically show effacement of the normal lymph node architecture by a **monotonous proliferation of atypical lymphocytes**. - While it can cause lymphadenopathy and fever, the specific histological features presented do not align with typical non-Hodgkin's lymphoma. *Angiolymphoid hyperplasia* - Characterized by **multiple vascular channels** lined by plump endothelial cells with **lymphoid infiltrates**. - It often presents as subcutaneous nodules, usually in the head and neck region, and lacks the follicular changes seen here. *IgG4 related disease* - Histologically, this disease is characterized by a **dense lymphoplasmacytic infiltrate rich in IgG4-positive plasma cells**, storiform fibrosis, and obliterative phlebitis. - While it can cause lymph node enlargement, the specific follicular changes in the image are not typical of IgG4-related disease. [Practice more Pathology PYQs on OnCourse]

Q: Identify the structure marked in the image of cardiac myocyte. (AIIMS Nov 2018)

Lipofuscin granules. ***Lipofuscin granules*** - The image displays electron-dense, irregular structures, characteristic of **lipofuscin granules**, which are wear-and-tear pigments accumulating in aging cardiac myocytes. - They are typically located near the nucleus and appear dark due to their complex lipid-protein composition. *Lysosomes* - Lysosomes are typically smaller, more uniformly shaped, and contain hydrolytic enzymes, which is not clearly depicted. - While involved in cellular waste breakdown, they do not typically accumulate as large, intensely electron-dense, irregular aggregates like those shown. *Phagolysosome* - A phagolysosome forms when a phagosome fuses with a lysosome, containing engulfed material often of foreign or cellular debris origin. - The image does not show evidence of recently engulfed material or the typical morphology of a phagocytic vesicle. *Inflammasome* - An inflammasome is a multi-protein intracellular complex involved in the inflammatory response, not a visibly distinct organelle with this characteristic electron microscopic appearance. - It is a signaling platform, not a storage granule, and would not appear as dense, granular deposits in a routine electron micrograph. [Practice more Pathology PYQs on OnCourse]

Q: Identify the lesion in a 20-year-old male whose foot X-ray is shown below:

Mycetoma. ***Mycetoma*** - The X-ray image shows a **lytic lesion** with surrounding sclerosis in the calcaneus, indicated by the arrow, which is characteristic of **mycetoma**. The histological image reveals an inflammatory infiltrate with **pigmented fungal grains (brown aggregates)**, confirming the diagnosis. - Mycetoma is a chronic granulomatous infection of subcutaneous tissues, often extending to bone, particularly in the foot. Its characteristic features include **grains (colonies of microorganisms)** within the lesions. *Ochronosis* - Ochronosis would show **dark discoloration of cartilage** and connective tissues due to **homogentisic acid** deposition, leading to degenerative arthritis. This would appear on X-ray as **calcification of cartilage** (e.g., intervertebral discs, menisci) rather than focal lytic lesions with grains. - The histological image would show characteristic **ochre-colored pigment deposits**, not fungal grains. *Haemophilic pseudo-tumour* - A haemophilic pseudo-tumour is a rare complication of hemophilia, often presenting as a **large, expanding lesion** within bone or soft tissue, typically due to recurrent hemorrhage. - X-rays would reveal a **well-defined, expansile lesion** with cortical thinning or bone destruction, and histology would show features of chronic hemorrhage, fibrous tissue, and hemosiderin deposition, not fungal grains. *Pigmented villonodular synovitis* - This condition involves **proliferation of synovial tissue**, often affecting large joints like the knee or hip, leading to bone erosions and cysts. - Histology would show **hyperplastic synovium** with hemosiderin deposition, multinucleated giant cells, and lipid-laden macrophages, but not fungal grains as seen in the microscopy image. [Practice more Pathology PYQs on OnCourse]

Question 1

Immunofluorescence staining pattern from a kidney biopsy from a 35-year-old patient presenting with proteinuria has been shown below. What is the most probable cause?

Accepted Answer

Lupus Nephritis

Answer

FSGS

Answer

Goodpasture syndrome

Answer

PSGN

Question 2

A macrophage engulfs different cells as shown in the image. This is known as?

Accepted Answer

Emperipolesis

Answer

Phagocytosis

Answer

Killing

Answer

Cytotoxicity

Question 3

A patient presents with intermittent fever, no weight loss and enlarged retroperitoneal lymph nodes. Peripheral smear is normal. Gross sample and its histopathology slide is shown below. Comment on the diagnosis.

Accepted Answer

Castleman disease

Answer

Non-Hodgkin's lymphoma

Answer

Angiolymphoid hyperplasia

Answer

IgG4 related disease

Question 4

Identify the structure marked in the image of cardiac myocyte. (AIIMS Nov 2018)

Accepted Answer

Lipofuscin granules

Answer

Lysosomes

Answer

Phagolysosome

Answer

Inflammasome

Question 5

Identify the lesion in a 20-year-old male whose foot X-ray is shown below:

Accepted Answer

Mycetoma

Answer

Ochronosis

Answer

Haemophilic pseudo-tumour

Answer

Pigmented villonodular synovitis

INI-CET 2018 — Pathology