General Pathology Practice Questions

Q: Histology in a child diagnosed with Gaucher's disease may show accumulation of which substance?

Glucocerebroside. **Explanation:** **Gaucher’s Disease** is the most common lysosomal storage disorder. It is an autosomal recessive condition caused by a deficiency of the enzyme **glucocerebrosidase** (also known as acid β-glucosidase). 1. **Why Option A is Correct:** Under normal physiological conditions, glucocerebrosidase cleaves glucose from ceramide. In Gaucher’s disease, the enzyme deficiency leads to the systemic accumulation of **glucocerebroside** (glucosylceramide) within the lysosomes of macrophages [1]. These laden macrophages are called **Gaucher cells**, characterized by a pathognomonic "wrinkled tissue paper" or "crumpled silk" appearance of the cytoplasm [1], [2]. 2. **Why Option B is Incorrect:** **Galactolipids** (specifically galactocerebroside) accumulate in **Krabbe’s disease** due to a deficiency of the enzyme galactocerebrosidase. 3. **Why Option C and D are Incorrect:** Since the metabolic defect in Gaucher’s is specific to the glucose-ceramide linkage, only glucocerebroside accumulates, making these options incorrect. **High-Yield Clinical Pearls for NEET-PG:** * **Gaucher Cells:** These are enlarged macrophages found primarily in the spleen, liver, and bone marrow [2]. They stain positive with **Periodic Acid-Schiff (PAS)**. * **Clinical Triad:** Hepatosplenomegaly (massive), bone involvement (Erlenmeyer flask deformity of the femur, bone crises), and cytopenias (due to hypersplenism) [1]. * **Biomarker:** Elevated levels of **serum chitotriosidase** and ACE are often seen. * **Treatment:** Enzyme Replacement Therapy (ERT) with recombinant enzymes (e.g., Imiglucerase) is the standard of care. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Genetic Disorders, p. 163. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Genetic Disorders, pp. 162-163.

Q: HMB 45 is a marker for which of the following?

Melanoma. **Explanation:** **HMB-45 (Human Melanoma Black-45)** is a highly specific monoclonal antibody used in immunohistochemistry (IHC) to identify **Melanoma** [1]. It reacts against **gp100**, a glycophosphoprotein found in the stage II melanosomes of melanocytes. While it is highly specific for melanocytic tumors, it is generally less sensitive than S-100, meaning it is excellent for confirming a diagnosis rather than screening. **Analysis of Options:** * **Option B (Melanoma):** Correct. HMB-45 is a classic marker for malignant melanoma [1]. It is particularly useful in distinguishing amelanotic melanoma (which lacks visible pigment) from other poorly differentiated tumors. * **Option A (Sarcoma):** Incorrect. Sarcomas are tumors of mesenchymal origin. Common markers include **Vimentin** (universal), Desmin (muscle), or CD34 (vascular). * **Option C (Carcinoma):** Incorrect. Carcinomas are of epithelial origin. The hallmark IHC marker for carcinomas is **Cytokeratin (CK)**. **High-Yield Clinical Pearls for NEET-PG:** * **S-100:** The most sensitive (but least specific) marker for melanoma. * **Melan-A (MART-1):** Another highly specific marker for melanocytic differentiation, often used alongside HMB-45. * **SOX10:** A reliable nuclear marker for both melanoma and nerve sheath tumors. * **HMB-45 Exceptions:** While primarily for melanoma, it can also be positive in **Angiomyolipoma (AML)** and Lymphangiomyomatosis (LAM), as these belong to the PEComa family of tumors. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Skin, pp. 1151-1152.

Question 1

Lipid peroxidation in cells exposed to ionizing radiation is initiated by?

Accepted Answer

Hydroxyl Radical

Answer

Catalase

Answer

Superoxide

Answer

Glutathione

Question 2

Histology in a child diagnosed with Gaucher's disease may show accumulation of which substance?

Accepted Answer

Glucocerebroside

Answer

Galactolipid

Answer

Both of the above

Answer

None of the above

Question 3

Migratory superficial thrombophlebitis is seen in which of the following conditions?

Accepted Answer

Carcinoma of the pancreas

Answer

Astrocytoma

Answer

Renal carcinoma

Answer

All of the above

Question 4

Which of the following is NOT an example of coagulative necrosis?

Accepted Answer

Brain infarct

Answer

Myocardial infarct

Answer

Kidney infarct

Answer

Adrenal infarct

Question 5

If both parents have sickle cell anemia, what is the likelihood of their offspring inheriting the disease?

Accepted Answer

100%

Answer

10%

Answer

25%

Answer

50%

Question 6

A 55-year-old man with diabetes and a long history of renal failure is awaiting organ transplant and is on hemodialysis. If this man develops amyloid deposits around his joints, they are likely to be composed of which of the following substances?

Accepted Answer

Beta2 microglobulin

Answer

Amyloid-associated protein

Answer

Amyloid light chains

Answer

Calcitonin precursors

Question 7

What is true about hemochromatosis?

Accepted Answer

Is genetically heterogenous

Answer

Cannot be treated by phlebotomy

Answer

Is completely penetrant

Answer

Is more common in females

Question 8

HMB 45 is a marker for which of the following?

Accepted Answer

Melanoma

Answer

Sarcoma

Answer

Carcinoma

Answer

None of the above

Question 9

Toll-like receptors are expressed in all of the following except:

Accepted Answer

B cells

Answer

Macrophages

Answer

Dendritic cells

Answer

T cells

Question 10

Sezary syndrome is classified under which of the following categories?

Accepted Answer

T cell leukemia

Answer

Lymphoma

Answer

B cell leukemia

Answer

Pigmented disorder of skin

General Pathology — MCQs

General Pathology — MCQs

On this page

Practice by Chapter

Want unlimited practice?