NEET-PG 2020 Practice Questions

Q: Identify the type of joint in the image provided.

Synovial joint. ***Synovial joint*** - The image depicts a **costovertebral joint**, which connects a rib to a thoracic vertebra. These joints are **diarthrotic**, meaning they are freely movable, characteristic of synovial joints. - Synovial joints are characterized by the presence of a **synovial cavity**, articular cartilage, an articular capsule, and synovial fluid, allowing for a wide range of motion. *Syndesmosis* - A syndesmosis is a type of **fibrous joint** where two bones are joined by a ligament or a membrane, allowing for very limited movement, such as the distal tibiofibular joint. - This definition does not match the image, which shows a joint designed for movement between the rib and vertebra. *Synarthrosis* - Synarthrosis is a classification for **immovable joints**, such as sutures in the skull. - The costovertebral joints, as shown, allow for movement during respiration and are therefore not synarthrotic. *Symphysis* - A symphysis is a type of **cartilaginous joint** where bones are joined by **fibrocartilage**, allowing for slight movement. Examples include the pubic symphysis or intervertebral discs. - The costovertebral joint shown in the image is a synovial articulation, not a cartilaginous joint.

Q: A 13-year-old child visits the OPD with complaints of not attaining menarche, and has a karyotype of 46,XX. On examination, there is clitoromegaly. Which enzyme is likely deficient?

21-alpha hydroxylase. ***21-alpha hydroxylase*** - A deficiency in **21-alpha hydroxylase** leads to **Congenital Adrenal Hyperplasia (CAH)**, shunting precursors towards **androgen production**. - In a 46,XX individual, this results in **virilization** such as **clitoromegaly** and **primary amenorrhea** due to excess androgens suppressing gonadotropin release and ovarian function. *17-alpha hydroxylase* - Deficiency in **17-alpha hydroxylase** in a 46,XX individual would lead to impaired sex steroid synthesis but **excess mineralocorticoids**, causing **hypertension** and **hypokalemia**. - While it causes **primary amenorrhea** due to lack of estrogen, it typically presents with **female external genitalia** that are underdeveloped, not virilized with clitoromegaly. *11-alpha hydroxylase* - There is no known functional enzyme called **11-alpha hydroxylase** in the steroid synthesis pathway. The relevant enzyme is **11-beta hydroxylase**, which, when deficient, leads to **CAH** with virilization and hypertension. - Assuming it refers to 11-beta hydroxylase, deficiency would cause **virilization** in 46,XX females but also lead to **hypertension** due to accumulation of 11-deoxycorticosterone, which is not mentioned in the presentation. *3-beta hydroxysteroid dehydrogenase* - Deficiency of **3-beta hydroxysteroid dehydrogenase** impairs the synthesis of **all classes of adrenal steroids** (glucocorticoids, mineralocorticoids, and sex steroids). - In 46,XX individuals, it leads to **females with ambiguous genitalia** (due to accumulation of DHEA) and **salt wasting**, but typically does not cause overt clitoromegaly and amenorrhea in the manner seen with 21-hydroxylase deficiency.

Q: Most common cause of death in SLE in children

Anemia and infections. ***Anemia and infections*** - **Infections** are a leading cause of death in pediatric SLE patients, often due to immunosuppression from the disease itself or its treatment. Although pediatric Systemic Lupus Erythematosus (SLE) is not a primary immune deficiency, the susceptibility to encapsulated bacteria and recurrent infections seen in primary B- and T-lymphocyte deficiencies mirrors the infection risks managed in these patients [1]. - **Anemia** can contribute to overall morbidity and mortality, although it is less directly a cause of death than severe infections or organ failure. *Lupus nephritis* - While **lupus nephritis** is a common and severe manifestation of SLE in children and a major cause of morbidity, particularly long-term kidney failure, it is not the most frequent immediate cause of death. - Advancements in treatment for nephritis have improved prognosis, shifting the leading cause of mortality to other factors. *Lupus cerebritis* - **Lupus cerebritis** (neuropsychiatric SLE) can be life-threatening, causing seizures, stroke, or psychosis, but it is less common as the primary cause of death compared to infections. - Its presence usually indicates severe disease requiring intensive treatment, but not the most common direct cause of death. *Libman sacks endocarditis* - **Libman-Sacks endocarditis** involves sterile vegetations on heart valves and is a known complication of SLE, but it rarely causes acute mortality in children. - It is more often associated with chronic complications like valvular dysfunction or a source of emboli rather than being the most common cause of death.

Q: 60-year-old female with a history of intermittent bleeding. What is the diagnosis based on the ultrasound image?

Endometrial polyp. ***Endometrial polyp*** - The ultrasound image shows a well-defined, **echogenic focal lesion within the endometrial cavity**, which is characteristic of an endometrial polyp. - In a 60-year-old female with intermittent bleeding, a polyp is a common cause of **postmenopausal bleeding** and is often identified as an intracavitary mass on ultrasound. - Endometrial polyps appear as **focal, hyperechoic or isoechoic masses** with a smooth contour projecting into the endometrial cavity. *Ca endometrium* - **Endometrial carcinoma** typically appears as diffuse endometrial thickening (>4-5 mm in postmenopausal women), irregular endometrial-myometrial interface, or heterogeneous endometrial echoes, often with evidence of myometrial invasion. - While bleeding is a cardinal symptom of endometrial carcinoma, the distinct **focal, well-circumscribed nature** of the lesion on ultrasound is less typical for carcinoma, which tends to be more diffuse and irregular. *Submucosal fibroid* - A **submucosal fibroid** (leiomyoma) is a benign smooth muscle tumor originating from the myometrium that protrudes into the endometrial cavity. - While it can appear as an intracavitary mass and cause abnormal bleeding, fibroids often have a more **heterogeneous or hypoechoic appearance** with posterior acoustic shadowing, compared to the isoechoic to hyperechoic appearance of a polyp. - The feeding vessel sign (blood flow at the base) is more characteristic of polyps than fibroids. *Endometrial hyperplasia* - **Endometrial hyperplasia** presents as **diffuse, uniform endometrial thickening** rather than a focal intracavitary mass. - It typically shows homogeneous increased echogenicity of the entire endometrium without a discrete, well-defined lesion as seen with a polyp. - While it can cause postmenopausal bleeding, the focal nature of the lesion in this case makes hyperplasia less likely.

Q: What is the best treatment option for a septate uterus?

Transcervical hysteroscopic resection of the septum. ***Transcervical hysteroscopic resection of the septum*** - This procedure involves using a **hysteroscope** to visualize and resect the **fibrous or muscular septum** that divides the uterine cavity, restoring a normal uterine shape. - It is considered the gold standard due to its **minimally invasive nature**, effectiveness in improving reproductive outcomes, and lower risk of complications compared to abdominal approaches. *Tompkins Metroplasty* - This is an **abdominal surgical procedure** primarily used for the repair of a **bicornuate uterus**, not typically for a septate uterus. - It involves resecting the uterine fundus to create a single uterine cavity, which is more invasive than hysteroscopic septum resection. *Jones metroplasty* - This procedure is also an **abdominal approach** used for the surgical correction of a **bicornuate uterus**, not a septate uterus. - It involves excising the septal portion and approximating the uterine walls. *Strassmann metroplasty* - This is another **abdominal surgical technique** that is primarily indicated for the repair of a **bicornuate or didelphys uterus**, where a large defect needs to be corrected. - It involves reconstructing the uterus through a fundal incision, which is significantly more invasive than hysteroscopic septal resection for a septate uterus.

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.

Q: What is the most serious complication of measles?

Pneumonia. ***Pneumonia*** - **Pneumonia**, particularly **giant cell pneumonia**, is the most common cause of **measles-related deaths** in young children. - It results from the **direct viral infection** of the lungs or a **secondary bacterial superinfection**. *Croup* - **Croup (laryngotracheobronchitis)** can be a complication of measles, but it is typically **less severe** and **less life-threatening** than pneumonia. - It primarily affects the **upper airways**, causing a barking cough and stridor. *Meningo-encephalitis* - **Meningo-encephalitis** is a serious, albeit **less common**, complication of measles, occurring in approximately 1 in 1,000 cases. - While potentially fatal or leading to neurological sequelae, it is **outranked by pneumonia** in terms of overall mortality attributed to measles. *Otitis media* - **Otitis media** (middle ear infection) is a common complication of measles, but it is generally **not life-threatening**. - It usually responds well to **antibiotic treatment** and rarely leads to severe outcomes.

Q: Which of the following is not considered a prokinetic agent?

Diphenylmethane. Diphenylmethane derivatives (e.g., bisacodyl, sodium picosulfate) are stimulant laxatives, not prokinetic agents. While they do increase colonic motility, they work by direct stimulation of the colonic mucosa and myenteric plexus, causing increased water secretion and peristalsis [3]. Prokinetic agents specifically enhance coordinated gastrointestinal motility through modulation of neurotransmitters (acetylcholine, dopamine, serotonin, motilin), whereas laxatives work through different mechanisms (osmotic effects, stimulation, bulk formation). Therefore, diphenylmethane derivatives are classified as laxatives, not prokinetics. Dopamine antagonist - Dopamine antagonists like metoclopramide and domperidone block D2 receptors in the chemoreceptor trigger zone and GI tract, enhancing acetylcholine release and promoting gastric emptying [2]. - They are commonly used as prokinetic agents and antiemetics [2]. 5HT4 agonist - 5HT4 agonists (e.g., cisapride, prucalopride) stimulate serotonin receptors in the enteric nervous system, increasing acetylcholine release and enhancing colonic motility [1]. - They are effective prokinetic agents for conditions like chronic constipation and gastroparesis [1]. Macrolides - Certain macrolide antibiotics, such as erythromycin, act as motilin receptor agonists at sub-antibiotic doses. - By mimicking motilin, they stimulate gastric and intestinal contractions (phase III of migrating motor complex), functioning as prokinetic agents.

Q: What is the Drug of Choice (DOC) for Onychomycosis?

Terbinafine. ***Terbinafine*** - **Terbinafine** is considered the **drug of choice** for **onychomycosis** due to its potent fungicidal activity against **dermatophytes**, which are the most common cause of nail infections [1]. - It accumulates in the nail plate at therapeutic levels, leading to high cure rates and a relatively good safety profile [2]. *Fluconazole* - While effective against some fungi, **fluconazole** is primarily fungistatic and generally less effective against dermatophytes compared to terbinafine for onychomycosis, resulting in lower cure rates [1]. - It is often preferred for **mucocutaneous candidiasis** and other systemic fungal infections [1]. *Itraconazole* - **Itraconazole** is an alternative for onychomycosis, often administered in pulse doses, but it can have more significant drug interactions and a higher risk of hepatic toxicity compared to terbinafine [1]. - Its efficacy against dermatophytes is comparable to terbinafine, but its side effect profile makes it a second-line option [1]. *Nystatin* - **Nystatin** is a topical antifungal effective primarily against **Candida species**, and is not effective against **dermatophytes**, which are the main pathogens in onychomycosis. - It is typically used for mucocutaneous candidiasis, such as oral thrush or vaginal yeast infections, and is not absorbed systemically.

Q: Which of the following is referred to as the "Window of the limbic system"?

Thalamus. ***Thalamus*** - The thalamus is often referred to as the **"relay station"** of the brain, processing and relaying most **sensory information** (except smell) to the cerebral cortex. - Due to its extensive connections with various limbic structures and its role in integrating and filtering emotional and motivational information before it reaches conscious awareness, it's considered the **"window of the limbic system"**. *Hypothalamus* - The hypothalamus primarily controls **autonomic functions** and maintains **homeostasis**, such as regulating temperature, hunger, thirst, and sleep cycles. - While it has strong connections with the limbic system, its main role is executive autonomic control rather than sensory integration. *Amygdala* - The amygdala is critically involved in processing **emotions**, particularly **fear** and **aggression**, and plays a key role in emotional memory. - It's a central component *within* the limbic system, but it doesn't serve as a general window or relay for the entire system's input. *Hippocampus* - The hippocampus is primarily responsible for **memory formation** (especially new episodic memories) and spatial navigation. - It is an important limbic structure, but its function is more specific to memory rather than being a gateway for broader limbic system activity.

Question 1

Identify the type of joint in the image provided.

Accepted Answer

Synovial joint

Answer

Syndesmosis

Answer

Synarthrosis

Answer

Symphysis

Question 2

A 13-year-old child visits the OPD with complaints of not attaining menarche, and has a karyotype of 46,XX. On examination, there is clitoromegaly. Which enzyme is likely deficient?

Accepted Answer

21-alpha hydroxylase

Answer

17-alpha hydroxylase

Answer

11-alpha hydroxylase

Answer

3-beta hydroxysteroid dehydrogenase

Question 3

Most common cause of death in SLE in children

Accepted Answer

Anemia and infections

Answer

Libman sacks endocarditis

Answer

Lupus cerebritis

Answer

Lupus nephritis

Question 4

60-year-old female with a history of intermittent bleeding. What is the diagnosis based on the ultrasound image?

Accepted Answer

Endometrial polyp

Answer

Ca endometrium

Answer

Submucosal fibroid

Answer

Endometrial hyperplasia

Question 5

What is the best treatment option for a septate uterus?

Accepted Answer

Transcervical hysteroscopic resection of the septum

Answer

Tompkins Metroplasty

Answer

Jones metroplasty

Answer

Strassmann metroplasty

Question 6

HBsAg is based on which principle

Accepted Answer

ELISA

Answer

Chemiluminescence

Answer

Immunofluorescence

Answer

Immunochromatography assays

Question 7

What is the most serious complication of measles?

Accepted Answer

Pneumonia

Answer

Croup

Answer

Otitis media

Answer

Meningo-encephalitis

Question 8

Which of the following is not considered a prokinetic agent?

Accepted Answer

Diphenylmethane

Answer

Dopamine antagonist

Answer

5HT4 agonist

Answer

Macrolides

Question 9

What is the Drug of Choice (DOC) for Onychomycosis?

Accepted Answer

Terbinafine

Answer

Fluconazole

Answer

Itraconazole

Answer

Nystatin

Question 10

Which of the following is referred to as the "Window of the limbic system"?

Accepted Answer

Thalamus

Answer

Hypothalamus

Answer

Hippocampus

Answer

Amygdala

NEET-PG 2020

Anatomy

Internal Medicine

Obstetrics and Gynecology

Pathology

Pediatrics

Pharmacology

Physiology