Anatomy
1 questionsAnterior Mediastinal nodes are included in which level of lymph nodes?
NEET-PG 2015 - Anatomy NEET-PG Practice Questions and MCQs
Question 1021: Anterior Mediastinal nodes are included in which level of lymph nodes?
- A. I
- B. V
- C. VI (Correct Answer)
- D. VII
Explanation: ***VI*** - Level VI lymph nodes are the **prevascular and retrotracheal nodes** located in the **anterior mediastinum** [1]. - According to the **IASLC (International Association for the Study of Lung Cancer)** lymph node mapping system, Level 6 nodes are specifically classified as anterior mediastinal nodes [1]. - These include nodes anterior to the superior vena cava and ascending aorta, and nodes between the trachea and esophagus [1]. *I* - Level I lymph nodes are located in the **low cervical, supraclavicular, and sternal notch** regions. - These are **extra-thoracic nodes** and not part of the mediastinal compartments. - They represent the highest mediastinal, supraclavicular, and sternal notch nodes [1]. *V* - Level V lymph nodes are the **subaortic (aortopulmonary window)** nodes [1]. - These are located in the space between the **aorta and pulmonary artery**, lateral to the ligamentum arteriosum [1]. - While mediastinal, they are specifically in the aortopulmonary window, not classified as anterior mediastinal. *VII* - Level VII lymph nodes are the **subcarinal nodes** located below the carina in the **middle mediastinum** [1]. - These nodes are positioned in the space beneath where the trachea bifurcates into the main bronchi [1]. - They are classified as middle mediastinal nodes, not anterior mediastinal nodes.
Dermatology
1 questionsAll of the following are premalignant conditions except which of the following?
NEET-PG 2015 - Dermatology NEET-PG Practice Questions and MCQs
Question 1021: All of the following are premalignant conditions except which of the following?
- A. Bowen's Disease
- B. Pyoderma Gangrenosum (Correct Answer)
- C. Xeroderma Pigmentosum
- D. Actinic Keratosis
Explanation: ***Pyoderma Gangrenosum*** - This is a **neutrophilic dermatosis** characterized by rapidly enlarging, painful ulcers with undermined, violaceous borders. It is an inflammatory condition, not premalignant. - While often associated with systemic diseases such as **inflammatory bowel disease** or **rheumatoid arthritis**, it does not inherently carry an increased risk of developing into skin cancer. *Bowen's Disease* - This is a form of **squamous cell carcinoma in situ**, meaning the cancerous cells are confined to the epidermis and have not yet invaded the dermis. - It is considered a **premalignant lesion** because it has the potential to progress to invasive squamous cell carcinoma if left untreated. *Actinic Keratosis* - These are **rough, scaly patches** on the skin caused by years of sun exposure, predominantly in fair-skinned individuals. - Actinic keratoses are considered **premalignant lesions** with a risk of transforming into invasive squamous cell carcinoma. *Xeroderma Pigmentosum* - This is a rare, **autosomal recessive genetic disorder** characterized by a defect in DNA repair mechanisms, specifically nucleotide excision repair. - Individuals with xeroderma pigmentosum have an extremely high risk of developing various **skin cancers** (basal cell carcinoma, squamous cell carcinoma, melanoma) at an early age due to their inability to repair UV-induced DNA damage.
Internal Medicine
3 questionsCAR-T cell therapy (Chimeric Antigen Receptor T-cell therapy) is being investigated for the treatment of which malignancy?
Crush Syndrome is associated with all of the following features except -
Which of the following types of kidney stones are commonly associated with urinary tract infections?
NEET-PG 2015 - Internal Medicine NEET-PG Practice Questions and MCQs
Question 1021: CAR-T cell therapy (Chimeric Antigen Receptor T-cell therapy) is being investigated for the treatment of which malignancy?
- A. Acute Lymphoblastic Leukemia (Correct Answer)
- B. Renal Cell Carcinoma
- C. Pancreatic Cancer
- D. Glioblastoma Multiforme
Explanation: ***Acute Lymphoblastic Leukemia*** - **CAR T-cell therapy** has shown remarkable success, particularly in treating refractory or relapsed **B-cell acute lymphoblastic leukemia (ALL)** in children and young adults. - The therapy targets the **CD19 antigen** found on malignant B-cells, leading to their destruction by engineered T-cells. *Renal Cell Carcinoma* - While immune therapies are used for **renal cell carcinoma (RCC)**, traditional CAR T-cell therapy targeting specific antigens has not yet achieved widespread clinical success for this solid tumor. - RCC often presents with a **heterogeneous antigenic landscape**, making it challenging for single-target CAR T-cells. *Pancreatic Cancer* - **Pancreatic cancer** is a challenging malignancy due to its dense stroma and immunosuppressive microenvironment, which limits T-cell infiltration and efficacy. - CAR T-cell therapy for pancreatic cancer is still largely in **early-stage clinical trials**, facing significant hurdles in solid tumor treatment. *Glioblastoma Multiforme* - **Glioblastoma multiforme (GBM)** is an aggressive brain tumor with unique challenges for CAR T-cell therapy, including the **blood-brain barrier** and tumor heterogeneity. - Research is ongoing to develop CAR T-cells that can effectively target GBM, often using **regional delivery methods** or targeting multiple antigens.
Question 1022: Crush Syndrome is associated with all of the following features except -
- A. Hypercalcemia (Correct Answer)
- B. Hypocalcemia
- C. Hyperkalemia
- D. Increased serum creatinine
Explanation: ***Hypercalcemia*** - Crush syndrome involves massive **muscle damage** leading to the release of intracellular contents, but hypercalcemia is not typically seen acutely. - While skeletal muscle contains calcium, its release, if any, is usually outweighed by other electrolyte shifts and renal dysfunction, often leading to **hypocalcemia** due to calcium binding to damaged tissues and phosphate. *Hypocalcemia* - This is a common feature of **crush syndrome** because calcium ions move into damaged cells and bind to free fatty acids and damaged tissue. - The elevated **phosphate levels** released from damaged cells can also bind to circulating calcium, further reducing serum calcium. *Hyperkalemia* - One of the most dangerous complications of **crush syndrome**, resulting from the massive release of **intracellular potassium** from damaged muscle cells. - Can lead to **life-threatening arrhythmias** if not promptly managed. *Increased serum creatinine* - Damaged muscle releases large amounts of **creatinine**, which is a byproduct of muscle metabolism; this, along with **myoglobin** (leading to acute kidney injury), causes a significant increase in serum creatinine levels. - **Acute kidney injury** due to rhabdomyolysis is a hallmark of crush syndrome, leading to impaired clearance of waste products.
Question 1023: Which of the following types of kidney stones are commonly associated with urinary tract infections?
- A. Struvite stones (Correct Answer)
- B. Cystine stones
- C. Xanthine stones
- D. Calcium oxalate stones
Explanation: ***Struvite stones*** - **Struvite stones** (magnesium ammonium phosphate) are strongly associated with **urinary tract infections (UTIs)** caused by urease-producing bacteria like *Proteus* and *Klebsiella*. - These bacteria hydrolyze urea into ammonia and carbon dioxide, increasing urine pH and promoting the precipitation of struvite, often forming **staghorn calculi** [1]. *Cystine stones* - **Cystine stones** are caused by a **genetic defect** in amino acid transport, leading to increased excretion of cystine, ornithine, lysine, and arginine (COLA) in the urine. - They are not directly associated with UTIs but rather with a rare inherited metabolic disorder called **cystinuria**. *Xanthine stones* - **Xanthine stones** are very rare and typically occur in individuals with **xanthinuria**, a genetic disorder characterized by a deficiency in xanthine oxidase. - They are also not linked to UTIs but are a consequence of abnormal purine metabolism. *Calcium oxalate stones* - **Calcium oxalate stones** are the most common type of kidney stone, resulting from high levels of calcium and oxalate in the urine, often due to dietary factors, malabsorption, or idiopathic hypercalciuria. - While UTIs can complicate any kidney stone, **calcium oxalate stones** are not primarily *caused* by UTIs. [1]
Obstetrics and Gynecology
1 questionsWhich is false about stress urinary incontinence?
NEET-PG 2015 - Obstetrics and Gynecology NEET-PG Practice Questions and MCQs
Question 1021: Which is false about stress urinary incontinence?
- A. More common in men (Correct Answer)
- B. It is due to weakening of pelvic floor muscles
- C. Prostate surgery may be a cause
- D. It occurs during increased abdominal pressure
Explanation: ***More common in men*** - **Stress urinary incontinence (SUI)** is significantly more prevalent in **women** due to anatomical differences and factors like childbirth. - While it can occur in men, especially after prostate surgery, the overall incidence is higher in females. *It is due to weakening of pelvic floor muscles* - Weakening of the **pelvic floor muscles** is a primary cause of SUI, leading to insufficient support for the urethra and bladder neck. - This weakness compromises the ability to maintain urethral closure pressure during activity. *Prostate surgery may be a cause* - **Radical prostatectomy** for prostate cancer is a common cause of SUI in men, as it can damage the urethral sphincter. - Damage to the internal or external urethral sphincter during surgery impairs the ability to control urine flow. *It occurs during increased abdominal pressure* - SUI characteristically involves involuntary urine leakage during activities that increase **intra-abdominal pressure**, such as coughing, sneezing, laughing, or exercising. - This increased pressure overcomes the weakened urethral resistance, leading to urine loss.
Orthopaedics
1 questionsAdson's test is positive in -
NEET-PG 2015 - Orthopaedics NEET-PG Practice Questions and MCQs
Question 1021: Adson's test is positive in -
- A. Cervical rib (Correct Answer)
- B. Cervical spondylosis
- C. Cervical fracture
- D. Cervical dislocation
Explanation: ***Cervical rib*** - **Adson's test** assesses for **thoracic outlet syndrome (TOS)**, which can be caused by a cervical rib compressing the **subclavian artery** or **brachial plexus**. - A positive test occurs when the radial pulse diminishes or disappears upon specific head and arm maneuvers, indicating neurovascular compression. *Cervical spondylosis* - This condition involves **degenerative changes** in the cervical spine, such as bone spurs and disc herniation. - While it can cause neurological symptoms, it typically does not lead to a positive Adson's test, as the compression site is different from that assessed by the test. *Cervical fracture* - A cervical fracture is a **traumatic injury** to the bones of the neck. - Adson's test is not indicated for diagnosing fractures and performing it could exacerbate the injury. *Cervical dislocation* - Cervical dislocation is a severe injury where cervical vertebrae are **displaced from their normal alignment**. - Similar to fractures, Adson's test is not appropriate for diagnosing or evaluating dislocations and carries a risk of further injury.
Pediatrics
1 questionsWhich of the following urethral anomalies is the most common?
NEET-PG 2015 - Pediatrics NEET-PG Practice Questions and MCQs
Question 1021: Which of the following urethral anomalies is the most common?
- A. Hypospadias (Correct Answer)
- B. Pinhole meatus
- C. Epispadias
- D. Stricture of the urethra
Explanation: ***Hypospadias*** - **Hypospadias** is the most common urethral anomaly, occurring when the **urethral opening** is located on the underside of the penis rather than at the tip. - Its prevalence ranges from approximately **1 in 150 to 1 in 300 live male births**, making it significantly more frequent than other urethral malformations. *Pinhole meatus* - A **pinhole meatus** refers to an abnormally small urethral opening. - While it can be a component or consequence of other anomalies, it is **less common as a standalone finding** compared to hypospadias. *Epispadias* - **Epispadias** is a rare anomaly where the urethra opens on the **dorsal (top) aspect** of the penis. - Its incidence is much lower than hypospadias, estimated at **1 in 100,000 to 1 in 500,000 live births**. *Stricture of the urethra* - A **urethral stricture** is a narrowing of the urethra, often due to **scar tissue** from inflammation, trauma, or infection. - Although it can present at any age, it is more commonly an **acquired condition** rather than a congenital anomaly like hypospadias or epispadias.
Surgery
2 questionsWhat is the optimal timing for administering antibiotic prophylaxis before surgery?
Which of the following is NOT a feature of membranous urethral injury?
NEET-PG 2015 - Surgery NEET-PG Practice Questions and MCQs
Question 1021: What is the optimal timing for administering antibiotic prophylaxis before surgery?
- A. Immediately before induction of anesthesia
- B. 30-60 minutes before incision (Correct Answer)
- C. 2-3 hours before surgery
- D. Immediately after surgery
Explanation: ***30-60 minutes before incision*** - This is the **optimal timing** recommended by WHO, CDC, and major surgical guidelines for most commonly used prophylactic antibiotics (cefazolin, cefuroxime). - Ensures **peak tissue and serum concentrations** are achieved at the time of incision, providing maximum protection against surgical site infections. - Based on **pharmacokinetic principles**: the antibiotic must be present at bactericidal concentrations in tissues when bacterial contamination occurs. - Studies show this timing significantly reduces surgical site infection rates compared to other timings. *Immediately before induction of anesthesia* - While acceptable in some protocols, this may be too early if there is a delay between induction and incision. - Could result in **declining antibiotic levels** by the time the incision is made, especially for antibiotics with shorter half-lives. *2-3 hours before surgery* - This is **too early** for most antibiotics. - Tissue levels may have already **declined below therapeutic concentrations** by the time of incision. - Does not provide adequate protection during the critical period of bacterial contamination. *Immediately after surgery* - This is **treatment, not prophylaxis**. - Offers **no preventive benefit** against intraoperative contamination. - By this time, bacteria introduced during surgery have already adhered to tissues and begun forming biofilms.
Question 1022: Which of the following is NOT a feature of membranous urethral injury?
- A. blood at the meatus
- B. Retention of urine
- C. Pelvic fracture
- D. Perineal butterfly hematoma (Correct Answer)
Explanation: ***Perineal butterfly hematoma*** - A **perineal butterfly hematoma** is more characteristic of an injury to the **anterior urethra**, specifically the bulbar urethra, often caused by a straddle injury. - It occurs due to the extravasation of blood into the subcutaneous tissue of the perineum, outlining the shape of a butterfly. *blood at the meatus* - **Blood at the meatus** is a classic sign of urethral injury, regardless of the segment (anterior or posterior). - It indicates disruption of the urethral mucosa and bleeding from the damaged blood vessels. *Retention of urine* - **Retention of urine** can occur due to either a complete or partial urethral transection, preventing normal urine flow. - The inability to void can lead to bladder distension and is a significant symptom in assessing urethral trauma severity. *Pelvic fracture* - **Pelvic fractures** are frequently associated with **membranous urethral injuries** because the membranous urethra is fixed within the pelvic ring. - Shear forces from pelvic trauma can cause the prostatomembranous junction to avulse.