NEET-PG 2020 Practice Questions

Q: Episiotomy incision was extended posteriorly beyond perineal body injuring the structure immediately posterior to it. Which structure has been injured?

External anal sphincter. ***External anal sphincter*** - An overextended **episiotomy incision** that goes beyond the perineal body posteriorly will likely injure the **external anal sphincter**, which is immediately posterior to the perineal body [4]. - Injury to this sphincter can lead to **fecal incontinence** [1]. *Ischiocavernosus* - The **ischiocavernosus muscle** is located more laterally in the perineum and plays a role in clitoral erection, not directly posterior to the perineal body. - An episiotomy extending posteriorly would not typically involve this muscle. *Urethral sphincter* - The **urethral sphincter** is located anterior to the perineal body and surrounds the urethra [3]. - Injury to this sphincter is associated with anterior perineal trauma, not posterior extension of an episiotomy [3]. *Bulbospongiosus* - The **bulbospongiosus muscle** is a superficial perineal muscle that surrounds the vaginal orifice and contributes to the perineal body [4]. - While it can be involved in an episiotomy, the structure immediately posterior to the perineal body itself is the external anal sphincter [2].

Q: What is the nerve supply of the shown muscle?

Dorsal scapular. ***Dorsal scapular*** - The image points to the **levator scapulae muscle**, which elevates and rotates the scapula. - The **dorsal scapular nerve** (C5 root, with contributions from C3-C4) innervates the levator scapulae, as well as the rhomboid major and minor muscles. - This nerve arises from the C5 root of the brachial plexus and pierces through the middle scalene muscle. - Clinically, injury to the dorsal scapular nerve can cause **medial scapular winging** and difficulty elevating the shoulder. *Suprascapular* - The suprascapular nerve (C5-C6) primarily innervates the **supraspinatus and infraspinatus muscles**, which are involved in rotator cuff function. - It does not supply the levator scapulae muscle. - This nerve passes through the suprascapular notch beneath the superior transverse scapular ligament. *Dorsal rami of C1* - The **dorsal ramus of C1** (suboccipital nerve) primarily innervates the muscles of the suboccipital triangle: rectus capitis posterior major and minor, obliquus capitis superior and inferior. - These nerves are involved in fine head and neck movements but do not innervate the levator scapulae. - The levator scapulae receives segmental innervation from C3-C4 cervical nerves directly, in addition to the dorsal scapular nerve. *Subscapular* - The subscapular nerves (upper and lower, from C5-C6) innervate the **subscapularis muscle**, which is part of the rotator cuff. - They also innervate the **teres major muscle**, but not the levator scapulae. - These are branches from the posterior cord of the brachial plexus.

Q: In a preterm baby with respiratory distress syndrome, which of the following lipids would be deficient?

Lecithin. ***Lecithin*** - **Lecithin** (also known as **phosphatidylcholine**) is the primary component of **surfactant** in the lungs, which reduces surface tension and prevents alveolar collapse. - In **preterm babies**, insufficient production of lecithin due to immature lung development leads to **respiratory distress syndrome (RDS)**. *Cardiolipin* - **Cardiolipin** is a major phospholipid found in the **inner mitochondrial membrane**, crucial for oxidative phosphorylation. - Deficiency is associated with mitochondrial disorders like **Barth syndrome**, not primary respiratory distress. *Sphingomyelin* - **Sphingomyelin** is a significant component of **cell membranes** and **myelin sheaths**, important for nerve insulation. - While present in the lungs, its primary role is not in surface tension reduction, and its deficiency is not directly linked to RDS. *Phosphatidylinositol* - **Phosphatidylinositol** is a precursor for various **signaling molecules** and plays a role in cell membrane structure. - While involved in cellular processes, it is not the critical surfactant component whose deficiency causes RDS.

Q: Which of the following is the etiology of Werner syndrome?

Short telomere with damaged DNA and loss of helicase. ***Short telomere with damaged DNA and loss of helicase*** - **Werner syndrome** is an **autosomal recessive disorder** characterized by **premature aging** due to mutations in the *WRN* gene, which codes for a **RecQ-type DNA helicase**. - The dysfunctional helicase leads to defects in **DNA replication, repair, and transcription**, resulting in **genomic instability**, **damaged DNA**, and **accelerated telomere attrition** (short telomeres). *Increased length of telomere* - **Increased telomere length** is generally associated with a **reduced rate of cellular aging** and is not characteristic of Werner syndrome or other premature aging disorders. - In most aging processes and syndromes like Werner, **telomeres tend to shorten** over time due to incomplete replication and oxidative stress. *Increased advanced glycation end products* - **Advanced glycation end products (AGEs)** accumulate in various tissues during normal aging and in conditions like diabetes, contributing to vascular and organ damage. - While AGEs play a role in the broader aging process, they are not the primary underlying genetic defect or direct etiology of Werner syndrome, which is a **DNA repair disorder**. *Decreased lipid peroxidation* - **Lipid peroxidation** is a process by which **free radicals** attack lipids, leading to cellular damage and is often associated with oxidative stress and aging. - A **decrease in lipid peroxidation** would generally be considered protective against aging-related damage, which is the opposite of what is seen in Werner syndrome, where there's an accelerated aging phenotype and increased cellular stress.

Q: Which of the following is classified as a Category A bioterrorism agent?

Bacillus anthracis. ***Bacillus anthracis*** - **Anthrax**, caused by *Bacillus anthracis*, is a prime example of a Category A bioterrorism agent due to its high mortality, ease of dissemination, and potential for major public health impact. - Category A agents pose the **greatest threat** to public health and national security. *Clostridium perfringens* - *Clostridium perfringens* is classified as a **Category B bioterrorism agent**. - While it causes **gas gangrene** and food poisoning with moderate severity, it lacks the **high transmissibility** and widespread impact characteristic of Category A agents. *NIPAH virus* - **Nipah virus** is classified as a Category C priority pathogen. - It has the potential for high morbidity and mortality, but its **epidemiological characteristics** (e.g., lower transmissibility than Category A agents) preclude its inclusion in Category A. *Coxiella burnetii* - *Coxiella burnetii*, the causative agent of **Q fever**, is classified as a Category B bioterrorism agent. - Category B agents are moderately easy to disseminate and can cause **moderate morbidity** and low mortality, which is less severe than Category A agents.

Q: A 35-year-old HIV positive patient comes with intractable diarrhea, crampy abdominal pain and vomiting. Biopsy of small intestine was taken which shows oocysts <10 µm as given below. What is the appropriate diagnosis?

Cryptosporidium parvum. ***Cryptosporidium parvum*** - The classic presentation in an **HIV-positive** patient with **intractable diarrhea**, **abdominal pain**, and identifying **acid-fast oocysts <10 µm** in a small intestine biopsy strongly indicates *Cryptosporidium parvum*. - This parasite is a common cause of **severe diarrheal illness** in immunocompromised individuals. *Giardia lamblia* - While *Giardia lamblia* causes **diarrhea** and **abdominal cramps**, its cysts are larger (10-14 µm) and typically pear-shaped trophozoites are seen, not small acid-fast oocysts. - It usually causes **malabsorption** and **steatorrhea**, and is not typically associated with intractable diarrhea in HIV patients to the same extent as *Cryptosporidium*. *CMV* - **Cytomegalovirus (CMV)** can cause **colitis** or **enteritis** in immunocompromised patients, leading to diarrhea and abdominal pain. - However, diagnosis involves identifying **intranuclear inclusions** (cytomegalic cells) on biopsy, not small cysts or oocysts. *Isospora belli* - *Isospora belli* is another coccidian parasite causing diarrhea in HIV patients, but its oocysts are **larger (20-30 µm)** and **ellipsoidal**, differentiating them from the smaller, round oocysts of *Cryptosporidium*. - Like *Cryptosporidium*, its oocysts are also **acid-fast**, but size and shape are key distinguishing features.

Q: Which of the following is most likely to be acquired by traumatic inoculation?

Sporothrix schenckii. ***Sporothrix schenckii*** - **Sporothrix schenckii** causes **sporotrichosis** (rose gardener's disease), which is classically acquired through **traumatic inoculation** via thorns, splinters, or plant material contaminated with the fungus. - This dimorphic fungus exists in soil and vegetation, and the mode of transmission is characteristically associated with **gardeners, farmers, and florists** who experience penetrating injuries during their work. - Presents as lymphocutaneous infection with nodular lesions along lymphatic channels. *Histoplasma capsulatum* - Causes histoplasmosis and is endemic to certain regions (Ohio and Mississippi River valleys). - Primarily acquired through **inhalation of microconidia** from soil contaminated with bird or bat droppings, not through traumatic inoculation. - Presents as pulmonary infection in most cases. *Coccidioides immitis* - Causes coccidioidomycosis (Valley Fever) and is found in arid regions of southwestern United States. - Acquired through **inhalation of airborne arthroconidia** from disturbed soil, not through traumatic inoculation. - While rare cases of primary cutaneous infection can occur, inhalation remains the typical route. *Aspergillus fumigatus* - Ubiquitous environmental mold associated with decaying organic matter. - Primarily causes disease through **inhalation of conidia**, leading to allergic reactions, aspergilloma, or invasive aspergillosis in immunocompromised patients. - Not typically associated with traumatic inoculation as the primary mode of infection.

Q: A 5-year-old child is having acute liver failure. Which one of the following criteria is not included in the King's College criteria?

Age < 11 years. ***Age < 11 years*** - Age is **NOT included** in the original King's College criteria for acute liver failure - King's College criteria are based on **biochemical parameters** (INR, bilirubin, pH, creatinine) and **clinical factors** (encephalopathy grade, jaundice-to-encephalopathy interval), not patient age - While **younger age may be a prognostic factor** in pediatric liver failure, it is not part of the formal King's College criteria used to predict poor prognosis or need for transplantation *INR > 6.5* - An **elevated INR > 6.5** (or PT > 100 seconds) is a **key criterion** in King's College criteria for non-paracetamol acute liver failure - Indicates severe **coagulopathy** and hepatic synthetic dysfunction - One of the most important predictors of poor outcome *Jaundice 7 days = subacute (worse prognosis, indicates need for transplant) - This temporal relationship is a **critical prognostic indicator** *Bilirubin > 300 mmol/L* - **Serum bilirubin > 300 μmol/L** (17.5 mg/dL) is explicitly included in King's College criteria for non-paracetamol ALF - Indicates severe **cholestasis** and hepatocellular dysfunction - Part of the multi-parameter assessment for transplant listing

Q: A patient was on lithium therapy for bipolar disorder for 6 months. She fasted for few days due to religious reasons and presented with coarse tremors, abdominal pain, nausea, dizziness & confusion. Which of the following should be done to assess her condition?

S. lithium levels. ***S. lithium levels*** - The patient's symptoms (coarse tremors, abdominal pain, nausea, dizziness, confusion) are classic for **lithium toxicity**, which is exacerbated by **dehydration** from fasting [1], [2]. - Measuring **serum lithium levels** is crucial for confirming the diagnosis and guiding immediate management [1]. *ECG* - While lithium toxicity can cause **cardiac arrhythmias** (QT prolongation, T-wave changes), an ECG is a secondary assessment to evaluate for complications, not the primary diagnostic test for toxicity itself. - An ECG doesn't directly measure lithium concentration, which is essential for diagnosing toxicity. *S. electrolyte* - **Electrolyte imbalances**, particularly **hyponatremia**, can worsen lithium toxicity by affecting its renal excretion [2]. - While important to check for contributing factors and guide supportive care, measuring electrolytes is secondary to confirming elevated lithium levels as the cause of symptoms. *MRI* - An **MRI of the brain** is not indicated for the initial assessment of suspected lithium toxicity. - It would only be considered if there were concerns for focal neurological deficits or other structural brain abnormalities, which are not directly suggested by the presented symptoms of lithium toxicity.

Q: A man is brought to the emergency after he fell into a man hole and injured his perineum. He feels the urge to micturate but is unable to pass urine and there is blood at the tip of the meatus with extensive swelling of the penis and scrotum. What is the location of the injury?

Bulbar urethra. ***Bulbar urethra*** - Injury to the **bulbar (spongy) urethra** in the perineum, often from a straddle injury or fall into a manhole, typically causes the extravasation of urine and blood into the **superficial perineal pouch**. - This leads to **extensive swelling of the penis and scrotum** (butterfly hematoma) because the superficial perineal fascia (Colles' fascia) is continuous with dartos fascia of the penis and scrotum, preventing blood from extending into the thighs or abdominal wall, combined with an inability to micturate with blood at the meatus. *Membranous urethra* - Injury to the **membranous urethra** is usually associated with **pelvic fractures** and tends to cause extravasation into the **deep perineal space** and then the retroperitoneum, leading to swelling in the lower abdomen or around the anus, not primarily the penis and scrotum. - While it can cause inability to micturate and blood at the meatus, the characteristic extensive swelling of the penis and scrotum points away from this location. *Prostatic urethra* - Injuries to the **prostatic urethra** are rare and typically occur with **severe pelvic crush injuries** given its protected position deep within the pelvis. - While it would cause inability to urinate, the nature of the fall and the distribution of swelling (predominantly penis and scrotum) are not typical for prostatic urethral injury. *Bladder* - A bladder injury from a fall would likely present with suprapubic pain and hematuria, but the inability to urinate combined with **blood at the meatus** and extensive swelling limited to the penis and scrotum is not characteristic of isolated bladder trauma. - **Blood at the meatus** is a classic sign of urethral, not typically bladder, injury.

Question 1

Episiotomy incision was extended posteriorly beyond perineal body injuring the structure immediately posterior to it. Which structure has been injured?

Accepted Answer

External anal sphincter

Answer

Ischiocavernosus

Answer

Urethral sphincter

Answer

Bulbospongiosus

Question 2

What is the nerve supply of the shown muscle?

Accepted Answer

Dorsal scapular

Answer

Suprascapular

Answer

Dorsal rami of C1

Answer

Subscapular

Question 3

In a preterm baby with respiratory distress syndrome, which of the following lipids would be deficient?

Accepted Answer

Lecithin

Answer

Cardiolipin

Answer

Sphingomyelin

Answer

Phosphatidylinositol

Question 4

Which of the following is the etiology of Werner syndrome?

Accepted Answer

Short telomere with damaged DNA and loss of helicase

Answer

Increased length of telomere

Answer

Increased advanced glycation end products

Answer

Decreased lipid peroxidation

Question 5

Which of the following is classified as a Category A bioterrorism agent?

Accepted Answer

Bacillus anthracis

Answer

Clostridium perfringens

Answer

NIPAH virus

Answer

Coxiella burnetii

Question 6

A 35-year-old HIV positive patient comes with intractable diarrhea, crampy abdominal pain and vomiting. Biopsy of small intestine was taken which shows oocysts <10 µm as given below. What is the appropriate diagnosis?

Accepted Answer

Cryptosporidium parvum

Answer

Giardia lamblia

Answer

CMV

Answer

Isospora belli

Question 7

Which of the following is most likely to be acquired by traumatic inoculation?

Accepted Answer

Sporothrix schenckii

Answer

Coccidioides immitis

Answer

Histoplasma capsulatum

Answer

Aspergillus fumigatus

Question 8

A 5-year-old child is having acute liver failure. Which one of the following criteria is not included in the King's College criteria?

Accepted Answer

Age < 11 years

Answer

INR > 6.5

Answer

Jaundice < 7 days before development of encephalopathy

Answer

Bilirubin > 300 mmol/L

Question 9

A patient was on lithium therapy for bipolar disorder for 6 months. She fasted for few days due to religious reasons and presented with coarse tremors, abdominal pain, nausea, dizziness & confusion. Which of the following should be done to assess her condition?

Accepted Answer

S. lithium levels

Answer

ECG

Answer

MRI

Answer

S. electrolytes

Question 10

A man is brought to the emergency after he fell into a man hole and injured his perineum. He feels the urge to micturate but is unable to pass urine and there is blood at the tip of the meatus with extensive swelling of the penis and scrotum. What is the location of the injury?

Accepted Answer

Bulbar urethra

Answer

Membranous urethra

Answer

Prostatic urethra

Answer

Bladder

NEET-PG 2020

Anatomy

Biochemistry

Community Medicine

Microbiology

Pediatrics

Psychiatry

Surgery