NEET-PG 2012 - Pathology Practice Questions

Q: What laboratory findings are associated with common variable hypogammaglobulinemia?

Low serum immunoglobulin levels. ***Low serum immunoglobulin levels*** - **Common variable hypogammaglobulinemia (CVID)** is characterized by significantly **low levels of IgG, IgA, and/or IgM** due to impaired B cell differentiation into plasma cells. - This deficiency in antibodies is the hallmark of the disorder, explaining the increased susceptibility to infections. *Decreased B cell count* - While CVID involves impaired B cell function, the **B cell counts** in the peripheral blood are typically **normal** or sometimes even elevated [1]. - The problem lies in their inability to differentiate and produce adequate antibodies, not in their numerical presence [1]. *Increased B cell count* - An increased B cell count is not a characteristic finding in CVID; peripheral B cell numbers are usually normal [1]. - If B cell counts are significantly increased, other conditions such as certain **lymphoproliferative disorders** should be considered. *Neutropenia* - **Neutropenia** (low neutrophil count) is not a primary diagnostic feature of CVID, although it can occur in some patients with autoimmune complications. - The defining laboratory finding is the **deficiency of immunoglobulins**, leading to recurrent infections. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Diseases of the Immune System, pp. 249-250.

Q: Li–Fraumeni syndrome is associated with mutations in which of the following genes?

Gene TP53. ***Gene TP53*** - Li-Fraumeni syndrome is a rare, inherited cancer susceptibility syndrome associated with germline mutations in the **TP53 tumor suppressor gene**. - The **TP53 gene** encodes the p53 protein, which plays a critical role in cell cycle arrest, DNA repair, and initiation of apoptosis in response to cellular stress, thus preventing tumor formation. *Gene P21* - The **p21 gene** (CDKN1A) is a cyclin-dependent kinase inhibitor that acts downstream of p53, mediating p53-induced cell cycle arrest. - While p21 is involved in the p53 pathway, mutations in p21 itself are not the primary cause of Li-Fraumeni syndrome. *Gene RB1* - The **RB1 gene** encodes the retinoblastoma protein, a tumor suppressor involved in cell cycle regulation, particularly in controlling passage from G1 to S phase. - Mutations in **RB1** are primarily associated with hereditary retinoblastoma and osteosarcoma, not Li-Fraumeni syndrome. *Gene BRCA1* - The **BRCA1 gene** is a tumor suppressor gene involved in DNA repair, especially homologous recombination. - Germline mutations in **BRCA1** are strongly associated with hereditary breast and ovarian cancer syndrome, not Li-Fraumeni syndrome.

Q: All of the following statements about Giant cell arteritis are true except?

Involves large to small sized arteries. ***Involves large to small sized arteries*** - Giant cell arteritis (GCA) predominantly affects **medium to large-sized arteries**, most commonly the branches of the **carotid artery**, such as the temporal arteries [1]. - While it can affect various arteries, it does not typically involve **small-sized arteries**, such as arterioles, directly as a primary site of inflammation. *Granulomatous inflammation* - GCA is characterized histologically by **granulomatous inflammation** within the arterial wall, which includes multinucleated **giant cells** and lymphocytes [2]. - This specific inflammatory pattern is a hallmark feature used in the diagnosis of GCA upon biopsy [2]. *Segmental nature of the involvement* - The arterial inflammation in GCA is often **segmental**, meaning that affected arteries may have inflamed and non-inflamed sections alternating along their length [2]. - This segmental involvement often necessitates **longer biopsies** (e.g., 2-3 cm for temporal artery biopsy) to increase the diagnostic yield. *Can involve the aorta and its major branches* - GCA can indeed affect the **aorta** (aortitis) and its major branches, leading to complications like **aneurysms** or **dissections**. - Involvement of these larger vessels can manifest as symptoms such as **claudication** in the limbs or asymptomatic aneurysms detectable on imaging [1]. **References:** [1] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Osteoarticular And Connective Tissue Disease, pp. 688-689. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Diseases of Infancy and Childhood, pp. 516-517.

Q: What change is seen in the vessels during the initial stage of Raynaud's phenomenon?

No pathological changes (functional vasospasm only). ***No pathological changes (functional vasospasm only)*** - Raynaud's phenomenon, particularly **primary Raynaud's** (Raynaud's disease), is characterized by **functional vasospasm** of arterioles, especially in fingers and toes, in response to cold or stress [1]. - In its initial stages, there are no structural changes or pathological alterations within the vessel walls; the vasoconstriction is entirely **functional** [1]. *Thrombosis* - **Thrombosis** involves the formation of a blood clot within a vessel, obstructing blood flow. - While severe Raynaud's can, in rare cases, lead to digital ischemia and microthrombosis, it is **not the primary or initial change** seen in typical Raynaud's phenomenon. *Fibrinoid necrosis* - **Fibrinoid necrosis** is a type of vascular damage associated with severe autoimmune diseases or malignant hypertension, where fibrin and plasma proteins deposit in the vessel wall. - This is a **structural, irreversible change** and is not characteristic of the initial, functional vasospasm seen in Raynaud's phenomenon. *Hyaline sclerosis* - **Hyaline sclerosis** is a change in small arteries and arterioles, often seen in benign essential hypertension or as part of the aging process, where the vessel wall thickens and becomes hyaline (glassy) due to plasma protein leakage and fibrosis. - This represents a **chronic structural change** and is not the acute, intermittent, functional vasoconstriction defining the initial stage of Raynaud's. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Diseases of Infancy and Childhood, pp. 520-522.

Q: A mutation in the transthyretin (TTR) protein causes which of the following types of amyloidosis?

Familial amyloidotic polyneuropathy. ***Familial amyloidotic polyneuropathy*** - This condition is specifically caused by **mutations in the transthyretin (TTR) protein**, leading to amyloid deposition primarily in nerves [1]. - It presents with **peripheral neuropathy**, including sensory and autonomic symptoms, which align with TTR mutations [1]. *Familial Mediterranean fever* - This is an autoinflammatory disorder caused by mutations in the **MEFV gene**, unrelated to transthyretin. - It is characterized by recurrent **fever, abdominal pain**, and **serositis**, not amyloidosis caused by TTR. *Prion protein associated amyloidosis* - Relates to prion diseases like **Creutzfeldt-Jakob disease**, caused by abnormal **prion proteins** rather than TTR [1]. - Symptoms are usually **neurodegenerative** in nature, not linked to familial amyloidogenic processes. *Dialysis associated amyloidosis* - This form of amyloidosis is due to the accumulation of **beta-2 microglobulin**, not mutations in TTR [1]. - Commonly presents with **joint pain** and carpal tunnel syndrome associated with long-term dialysis [1]. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Diseases of the Immune System, p. 266.

Q: Male to male transmission is seen in -

Autosomal dominant diseases. ***Autosomal dominant diseases*** - **Autosomal dominant** inheritance patterns involve a gene located on one of the **autosomes**, meaning it is not sex-linked. - Therefore, a father carrying an autosomal dominant gene can pass it to both sons and daughters with a **50% probability** for each child. - **Male-to-male transmission** is a hallmark feature that helps distinguish autosomal dominant from X-linked inheritance patterns. *Autosomal recessive* - **Autosomal recessive** diseases require **two copies** of the mutated gene (one from each parent) for the disease to manifest. - While a father can pass a recessive allele to his son, male-to-male transmission of the **disease phenotype** requires the mother to also be at least a carrier, making it not a defining feature of this inheritance pattern. - The key characteristic is horizontal pattern (affected siblings) rather than vertical transmission. *X-linked dominant* - In **X-linked dominant** inheritance, affected fathers **cannot** transmit the trait to their sons because sons inherit their **X chromosome** from their mother and their Y chromosome from their father. - All daughters of an affected father will inherit the affected X chromosome and thus the disease. - **Absence of male-to-male transmission** is a key distinguishing feature. *Mitochondrial disease* - **Mitochondrial diseases** are inherited exclusively from the **mother** to all her children, regardless of their sex. - Fathers with mitochondrial disease cannot transmit the condition to any of their children. - This shows **maternal inheritance only**, with no paternal transmission possible.

Q: What do Döhle bodies represent in neutrophils?

Presence of dilated endoplasmic reticulum in neutrophils. ***Presence of dilated endoplasmic reticulum in neutrophils*** - **Döhle bodies** are inclusions found in the cytoplasm of neutrophils, classic hallmarks of **severe infection** or inflammatory conditions. - They represent remnants of dilated **rough endoplasmic reticulum**, which appears as pale-blue, irregular aggregates on stained blood smears. *Increased mitochondria in neutrophils* - An increase in mitochondria is not a characteristic feature associated with Döhle bodies. - While mitochondria are essential for cellular energy production, their proliferation does not form visible inclusions known as Döhle bodies. *Golgi apparatus proliferation in neutrophils* - Proliferation of the Golgi apparatus is not typically observed as a Döhle body. - The Golgi apparatus is involved in protein modification and packaging, but its changes do not manifest as these specific inclusions. *Lysosomal activity in neutrophils* - Lysosomal activity involves the breakdown of cellular debris and pathogens and is not directly related to the formation of Döhle bodies. - Although lysosomes are abundant in neutrophils, their activity does not result in the presence of Döhle bodies.

Q: Oncocytic carcinoma arises from -

Collecting duct (intercalated cells). ***Collecting duct*** - Oncocytic carcinoma primarily originates from the **collecting ducts** of the kidney, where oncocytes are characteristically found [1]. - It is associated with specific **morphological features**, including abundant eosinophilic cytoplasm. *Loop of henle* - This part of the nephron primarily functions in **concentration of urine** and is not a common site for oncocytic tumors. - Tumors arising here typically do not exhibit **oncocytic features** and are more often linked to different renal cell types. *Glomerulus* - The glomerulus is involved in **filtration of blood** and lacks oncocytic differentiation. - Oncocytic carcinoma does not arise from glomerular structures, as it features distinct cellular characteristics. *Perivascular* - This term refers to the tissue surrounding blood vessels and is not a site for oncocytic carcinoma development. - Such tumors would not align with the histological features or origins typically seen in oncocytic carcinoma. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Kidney, p. 959.

Q: Which of the following is not typically seen in Disseminated Intravascular Coagulation (DIC)?

Normal aPTT. ***Normal APTT*** - In Disseminated Intravascular Coagulation (**DIC**), **APTT** is typically **prolonged** due to consumption of clotting factors [1]. - The presence of normal APTT indicates that coagulation pathways are not significantly affected, which is contrary to what is seen in DIC. *Fibrinogen decreased* - **Decreased fibrinogen levels** are common in DIC, reflecting its consumption during the coagulation process [1]. - This depletion is linked to the increased clotting and is a hallmark of DIC, making this statement false in the context of the question. *Thrombocytopenia* - **Thrombocytopenia** occurs in DIC as platelets are consumed during the formation of microclots [1]. - A significant drop in platelet count is a key feature of DIC, therefore this statement does not align with the "except" clause. *PT elevation* - Prothrombin Time (**PT**) is usually **elevated** in DIC due to the consumption of clotting factors [1]. - This reflects the ongoing activation of the coagulation cascade, supporting the exclusion in the question context. **References:** [1] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Blood And Bone Marrow Disease, pp. 625-626.

Q: What occurs during the stage of Grey hepatization?

Accumulation of fibrin. ***Accumulation of fibrin*** - Grey hepatization is characterized by the **presence of fibrinous exudate** in the alveoli, indicating significant lung pathology, usually in cases of pneumonia [1,2]. - This stage follows red hepatization and reflects the **progression of inflammation** within the lung tissue [1,2]. *RBC's fill the alveoli* - This occurs during the **red hepatization** stage, where RBCs invade alveoli, not grey hepatization [1,2]. - **Grey hepatization** is marked by **fibrinous deposits** instead of erythrocytes [1,2]. *Organisms fill the alveoli* - While organisms, such as bacteria, can be present, they are more characteristic of the **initial infection phase** rather than grey hepatization [1]. - This stage reflects more on the **inflammatory response** than the presence of pathogens. *WBC's fill the alveoli* - The infiltration of **WBCs (like neutrophils)** represents an earlier inflammatory process, usually preceding grey hepatization [1,2]. - In grey hepatization, the focus is on the **accumulation of fibrin**, not directly on WBC infiltration [1,2]. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Lung, pp. 711-712. [2] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Respiratory Tract Disease, pp. 317-318.

Question 1

What laboratory findings are associated with common variable hypogammaglobulinemia?

Accepted Answer

Low serum immunoglobulin levels

Answer

Decreased B cell count

Answer

Increased B cell count

Answer

Neutropenia

Question 2

Li–Fraumeni syndrome is associated with mutations in which of the following genes?

Accepted Answer

Gene TP53

Answer

Gene RB1

Answer

Gene BRCA1

Answer

Gene P21

Question 3

All of the following statements about Giant cell arteritis are true except?

Accepted Answer

Involves large to small sized arteries

Answer

Granulomatous inflammation

Answer

Segmental nature of the involvement

Answer

Can involve the aorta and its major branches

Question 4

What change is seen in the vessels during the initial stage of Raynaud's phenomenon?

Accepted Answer

No pathological changes (functional vasospasm only)

Answer

Thrombosis

Answer

Fibrinoid necrosis

Answer

Hyaline sclerosis

Question 5

A mutation in the transthyretin (TTR) protein causes which of the following types of amyloidosis?

Accepted Answer

Familial amyloidotic polyneuropathy

Answer

Familial Mediterranean fever

Answer

Dialysis associated amyloidosis

Answer

Prion protein associated amyloidosis

Question 6

Male to male transmission is seen in -

Accepted Answer

Autosomal dominant diseases

Answer

Autosomal recessive

Answer

X-linked dominant

Answer

Mitochondrial disease

Question 7

What do Döhle bodies represent in neutrophils?

Accepted Answer

Presence of dilated endoplasmic reticulum in neutrophils

Answer

Increased mitochondria in neutrophils

Answer

Golgi apparatus proliferation in neutrophils

Answer

Lysosomal activity in neutrophils

Question 8

Oncocytic carcinoma arises from -

Accepted Answer

Collecting duct (intercalated cells)

Answer

Perivascular region

Answer

Renal glomerulus

Answer

Loop of Henle

Question 9

Which of the following is not typically seen in Disseminated Intravascular Coagulation (DIC)?

Accepted Answer

Normal aPTT

Answer

Thrombocytopenia

Answer

PT elevation

Answer

Fibrinogen decreased

Question 10

What occurs during the stage of Grey hepatization?

Accepted Answer

Accumulation of fibrin

Answer

Red blood cells fill the alveoli

Answer

White blood cells fill the alveoli

Answer

Bacteria fill the alveoli

NEET-PG 2012 — Pathology