General Pathology Practice Questions

Q: A cyst arising from the rests of Malassez is:

Radicular cyst. **Explanation:** The **Radicular cyst** (also known as a Periapical cyst) is the most common inflammatory odontogenic cyst. It arises from the **epithelial rests of Malassez**, which are remnants of Hertwig’s epithelial root sheath (HERS) located in the periodontal ligament [1]. When a tooth becomes non-vital due to caries or trauma, the resulting inflammation (periapical granuloma) stimulates these dormant epithelial rests to proliferate, eventually leading to cyst formation [1]. **Analysis of Options:** * **Dentigerous Cyst:** This is a developmental cyst that originates from the **reduced enamel epithelium** (REE). It typically surrounds the crown of an unerupted tooth (most commonly the mandibular 3rd molar) and attaches at the cementoenamel junction. * **Dental Cyst:** This is a general, non-specific term often used interchangeably with radicular cysts in older literature, but in a competitive exam context, "Radicular cyst" is the precise pathological diagnosis for rests of Malassez origin. * **Keratocyst (Odontogenic Keratocyst/OKC):** This arises from the **dental lamina** (rests of Serres). It is known for its aggressive behavior, high recurrence rate, and association with Gorlin-Goltz syndrome. **NEET-PG High-Yield Pearls:** * **Rests of Malassez:** Associated with Radicular cysts (Inflammatory). * **Rests of Serres (Dental Lamina):** Associated with OKC and Ameloblastoma (Developmental/Neoplastic). * **Reduced Enamel Epithelium:** Associated with Dentigerous cysts. * **Rushton bodies:** Eosinophilic, linear, or curved structures found in the epithelial lining of radicular cysts (highly characteristic). * **Radiology:** Radicular cysts appear as well-defined unilocular radiolucencies at the apex of a **non-vital** tooth. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Head and Neck, pp. 741-742.

Q: A lesion 3 cm away from the gastroesophageal junction contains columnar epithelium. What is such a lesion called?

Metaplasia. ### Explanation **Correct Answer: A. Metaplasia** **Why Metaplasia is correct:** Metaplasia is defined as a reversible change in which one adult cell type (epithelial or mesenchymal) is replaced by another adult cell type. In this clinical scenario, the normal lining of the lower esophagus is **stratified squamous epithelium**. When exposed to chronic acid reflux (GERD), the esophagus adapts by replacing the squamous cells with **columnar epithelium** (with goblet cells), which is more resistant to acid. This specific transformation at the gastroesophageal junction is known as **Barrett’s Esophagus**. **Why the other options are incorrect:** * **B. Hyperplasia:** This refers to an increase in the *number* of cells in an organ or tissue, usually resulting in increased volume. The cell type remains the same. * **C. Dysplasia:** This refers to disordered growth and maturation of an epithelium. It is characterized by a loss of architectural uniformity and individual cell pleomorphism. While Barrett’s can progress to dysplasia, the initial change from squamous to columnar is metaplasia. * **D. Anaplasia:** This is a hallmark of malignancy. It refers to a total lack of differentiation, where cells lose their structural and functional resemblance to normal adult cells. **High-Yield Clinical Pearls for NEET-PG:** * **Barrett’s Esophagus:** It is the most common example of **Squamous-to-Columnar Metaplasia**. * **Risk of Malignancy:** Barrett’s esophagus is a significant risk factor for **Esophageal Adenocarcinoma** (not squamous cell carcinoma). * **Vitamin A Deficiency:** Can lead to **Squamous Metaplasia** in the respiratory tract (columnar to squamous). * **Connective Tissue Metaplasia:** Formation of bone in soft tissue following trauma is called **Myositis Ossificans**.

Q: What is the cause of nephrocalcinosis in granulomatous diseases?

Increased conversion to 1,25-dihydroxyvitamin D. **Explanation:** In granulomatous diseases such as **Sarcoidosis** and **Tuberculosis**, hypercalcemia and subsequent nephrocalcinosis occur due to the dysregulated metabolism of Vitamin D. 1. **Mechanism (Why B is correct):** Normally, the conversion of 25-hydroxyvitamin D to its active form, **1,25-dihydroxyvitamin D (Calcitriol)**, is strictly regulated by the enzyme **1-alpha-hydroxylase** in the kidneys, under the control of PTH [2]. However, in granulomatous diseases, the **activated macrophages** within the granulomas express 1-alpha-hydroxylase independently of PTH. This leads to the autonomous, excessive production of calcitriol, which increases intestinal calcium absorption and bone resorption, resulting in hypercalcemia, hypercalciuria, and nephrocalcinosis. 2. **Analysis of Incorrect Options:** * **Option A:** While increased calcium absorption occurs, it is the *consequence* of the primary pathology (elevated 1,25-dihydroxyvitamin D), not the root cause. * **Option C:** Dystrophic calcification occurs in necrotic or damaged tissues with normal serum calcium levels. In granulomatous disease, the calcification is **metastatic** (due to high serum calcium). * **Option D:** Mutations in the calcium-sensing receptor (CaSR) are associated with Familial Hypocalciuric Hypercalcemia (FHH), not granulomatous disease [1]. **High-Yield NEET-PG Pearls:** * **Classic Presentation:** A patient with bilateral hilar lymphadenopathy (Sarcoidosis) presenting with kidney stones or polyuria. * **Lab Findings:** High Calcium, High Phosphate, **Low PTH** (suppressed by high Ca), and **High 1,25-(OH)₂D**. * **Treatment:** Glucocorticoids are the mainstay as they inhibit the 1-alpha-hydroxylase enzyme in macrophages.

Question 1

What is the most common source of systemic emboli?

Accepted Answer

Mural thrombi

Answer

Varicose veins

Answer

Cardiac thrombi

Answer

Pulmonary embolism

Question 2

Which of the following is a protector or inhibitor of Apoptosis?

Accepted Answer

BCL-2

Answer

BRCA

Answer

RB

Answer

TGF-β

Question 3

A cyst arising from the rests of Malassez is:

Accepted Answer

Radicular cyst

Answer

Dental cyst

Answer

Dentigerous cyst

Answer

Keratocyst

Question 4

Which of the following cytoplasmic structures contains fragmented mitochondria?

Accepted Answer

Autophagosomes

Answer

Pinocytotic vacuoles

Answer

Primary lysosomes

Answer

Heterophagosomes

Question 5

A 40-year-old pregnant female in her third trimester presents with bilateral leg swelling. Which type of thrombosis is most likely to develop in this patient?

Accepted Answer

Venous

Answer

Arterial

Answer

Mural

Answer

Saddle

Question 6

A lesion 3 cm away from the gastroesophageal junction contains columnar epithelium. What is such a lesion called?

Accepted Answer

Metaplasia

Answer

Hyperplasia

Answer

Dysplasia

Answer

Anaplasia

Question 7

What is the cause of nephrocalcinosis in granulomatous diseases?

Accepted Answer

Increased conversion to 1,25-dihydroxyvitamin D

Answer

Increased absorption of calcium

Answer

Dystrophic calcification

Answer

Mutation in calcium-sensing receptor

Question 8

A 24-year-old man is found to have an increased total body iron concentration. Biopsy of his liver shows large amounts of granular golden-brown pigment which stains blue with Prussian blue stain. The presence of which one of the following diseases best explains these findings?

Accepted Answer

Hemochromatosis

Answer

Systemic amyloidosis

Answer

Chronic congestive heart failure

Answer

Advanced atrophy

Question 9

What stains are used for amyloid detection?

Accepted Answer

Thioflavin

Answer

Congo red

Answer

Eosin

Answer

Auramine

Question 10

Which of the following is an example of metastatic calcification?

Accepted Answer

Milk alkali syndrome

Answer

Psammoma bodies

Answer

Rheumatic heart disease

Answer

Monckeberg's medial calcific sclerosis

General Pathology — MCQs

General Pathology — MCQs

On this page

Practice by Chapter

Want unlimited practice?