Anatomy
1 questionsTrigone of urinary bladder develops from:
NEET-PG 2015 - Anatomy NEET-PG Practice Questions and MCQs
Question 1331: Trigone of urinary bladder develops from:
- A. Ectoderm
- B. Mesoderm (Correct Answer)
- C. None of the options
- D. Endoderm of urachus
Explanation: ***Mesoderm*** - The **trigone** of the urinary bladder develops from the **distal ends of the mesonephric (Wolffian) ducts**, which are **mesodermal in origin**. - These ducts are **absorbed into the posterior wall of the bladder**, forming the smooth triangular area between the two ureteric orifices and the internal urethral orifice [1]. - Although the epithelium of the trigone is later **replaced by endodermal epithelium** from the urogenital sinus, the **structural origin remains mesodermal**. - This is a classic example of **epithelial metaplasia** where endodermal epithelium replaces mesodermal tissue. *Endoderm of urachus* - The **urachus** is the fibrous remnant of the allantois that connects the apex of the bladder to the umbilicus. - It forms the **median umbilical ligament** in adults and does **not contribute to the trigone**. - The **urogenital sinus** (endodermal) forms the majority of the bladder body, but not the trigone. *Ectoderm* - The **ectoderm** forms the nervous system, epidermis, and sensory epithelia. - It does **not contribute** to the development of the urinary bladder or its trigone. - The urinary system is derived from **mesoderm** (kidneys, ureters, trigone) and **endoderm** (bladder body, urethra). *None of the options* - This is incorrect because **mesoderm** is the correct embryological origin of the trigone. - The mesonephric ducts that form the trigone are definitively mesodermal structures.
Forensic Medicine
1 questionsDuring a postmortem examination of a young adult found with a faded tattoo, relatives mentioned that the tattoo was once visible. What is the best method to identify the tattoo?
NEET-PG 2015 - Forensic Medicine NEET-PG Practice Questions and MCQs
Question 1331: During a postmortem examination of a young adult found with a faded tattoo, relatives mentioned that the tattoo was once visible. What is the best method to identify the tattoo?
- A. Use a spectrophotometer for analysis
- B. Illuminate with ordinary light
- C. Perform an X-ray examination
- D. Illuminate with ultraviolet (UV) light (Correct Answer)
Explanation: ***Illuminate with ultraviolet (UV) light*** - **UV light** causes residual tattoo pigments, even faded ones, to **fluoresce**, making them visible again for identification. - This method is particularly effective for **older or faded tattoos** where the pigment has degraded or spread. *Use a spectrophotometer for analysis* - A spectrophotometer is used to measure the **intensity of light** as a function of wavelength, which is useful for **analyzing chemical components or color intensity**. - While it can analyze pigments, it is not the primary or most practical method for merely **identifying the presence and pattern of a faded tattoo** on skin, especially in a postmortem context. *Illuminate with ordinary light* - **Ordinary visible light** is typically insufficient to reveal tattoos that have significantly faded or been subjected to processes that obscure them. - If the tattoo is already faded to the point of being invisible to the naked eye, **ordinary light will not enhance its visibility** as it lacks the specific wavelengths needed to cause fluorescence. *Perform an X-ray examination* - **X-rays** are used to visualize dense structures like **bones and foreign bodies**, not for examining skin or pigments. - Tattoo pigments are generally **not radiopaque** and would not be visible on an X-ray film, rendering this method useless for tattoo identification.
General Medicine
1 questionsWhich of the following syndromes is least likely to be associated with obesity?
NEET-PG 2015 - General Medicine NEET-PG Practice Questions and MCQs
Question 1331: Which of the following syndromes is least likely to be associated with obesity?
- A. Cushing syndrome
- B. Prader willi syndrome
- C. Sipple syndrome (Correct Answer)
- D. Pickwickian syndrome
Explanation: ***Sipple syndrome*** - Sipple syndrome, also known as **multiple endocrine neoplasia type 2**, is primarily associated with **medullary thyroid carcinoma** and does not typically correlate with obesity. - It includes signs like **pheochromocytoma** and **hyperparathyroidism**, but obesity is not a prominent feature. *Cushing syndrome* - Cushing syndrome leads to **excess cortisol**, commonly resulting in weight gain and central obesity [1]. - Characteristic features include **moon facies**, **buffalo hump**, and easy bruising, all associated with obesity [1]. *Pickwinian syndrome* - Pickwinian syndrome, characterized by **severe obesity**, is a condition primarily affecting physical stature and weight. - It is linked to **hypoventilation** and sleep apnea, reinforcing the presence of obesity. *Prader willi syndrome* - Prader-Willi syndrome is marked by **insatiable hunger** leading to **obesity** due to hypothalamic dysfunction [2]. - Individuals with this condition also demonstrate **hypotonia** and developmental delays, commonly accompanied by obesity [2]. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Endocrine System, pp. 1127-1129. [2] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Central Nervous System Synapse, pp. 454-455.
Microbiology
1 questionsNeutralization test is
NEET-PG 2015 - Microbiology NEET-PG Practice Questions and MCQs
Question 1331: Neutralization test is
- A. Widal test
- B. Weil-Felix test
- C. Paul-Bunnell test
- D. Nagler reaction (Correct Answer)
Explanation: ***Nagler reaction*** - The **Nagler reaction** is a biochemical test used to identify **Clostridium perfringens**, based on its ability to produce **alpha-toxin (lecithinase)**, which hydrolyzes lecithin in egg yolk agar. - It is a neutralization test because the lecithinase activity can be **inhibited (neutralized)** by antitoxin, leading to a diminished zone of opalescence or turbidity around colonies grown on egg yolk agar. *Widal test* - The **Widal test** is an **agglutination test** used to diagnose **typhoid fever** by detecting antibodies against *Salmonella typhi* O and H antigens in a patient's serum. - It measures the presence of antibodies that cause bacterial clumping, not the neutralization of a toxin. *Weil-Felix test* - The **Weil-Felix test** is an **agglutination test** used to diagnose **rickettsial infections** like epidemic typhus, scrub typhus, and Rocky Mountain spotted fever. - It detects antibodies that cross-react with specific **Proteus vulgaris** antigens, and is not a neutralization assay for toxins or enzymes. *Paul Bunnel test* - The **Paul-Bunnell test** is an **agglutination test** used to diagnose **infectious mononucleosis** by detecting heterophile antibodies that agglutinate sheep red blood cells. - It relies on the clumping of red blood cells by antibodies and does not involve the neutralization of a microbial product.
Radiology
5 questionsOn CT chest, the 'halo sign' is particularly associated with which condition in immunocompromised patients?
In a patient with a tender and rigid abdomen, what is the expected finding on X-ray?
Which of the following statements about lipoma is radiologically true?
Which of the following X-ray findings is associated with Chilaiditi syndrome?
Which of the following is NOT a typical ultrasonographic finding in autosomal recessive polycystic kidney disease (ARPKD)?
NEET-PG 2015 - Radiology NEET-PG Practice Questions and MCQs
Question 1331: On CT chest, the 'halo sign' is particularly associated with which condition in immunocompromised patients?
- A. Pulmonary hydatid cyst
- B. Round pneumonia
- C. Bronchiectasis
- D. Invasive pulmonary aspergillosis (Correct Answer)
Explanation: ***Invasive pulmonary aspergillosis*** - The **halo sign** on CT chest, characterized by a ground-glass opacity surrounding a nodule, is a classic radiographic finding in **invasive pulmonary aspergillosis**, especially in immunocompromised patients. - This sign represents hemorrhage around the fungal nodule and indicates active tissue invasion by *Aspergillus* species. *Pulmonary hydatid cyst* - Hydatid cysts are typically well-defined, thin-walled cystic lesions, often displaying the **water lily sign** if complicated by rupture, which is different from the halo sign. - These cysts are caused by the larval stage of *Echinococcus granulosus* and are not associated with a peripheral ground-glass opacity. *Round pneumonia* - Round pneumonia is a localized, **spherical consolidation** often seen in children, which does not typically exhibit the perilesional ground-glass opacity characteristic of the halo sign. - It usually represents bacterial infection and resolves with antibiotics, unlike the invasive fungal disease suggested by the halo sign. *Bronchiectasis* - Bronchiectasis is characterized by **irreversible dilation of the bronchi**, often appearing as "tram-track" opacities or "signet ring" signs on CT. - It is a chronic condition related to airway damage and mucus retention, and not associated with acute nodular lesions or the halo sign.
Question 1332: In a patient with a tender and rigid abdomen, what is the expected finding on X-ray?
- A. Blood under the diaphragm
- B. Air under the diaphragm (Correct Answer)
- C. Hazy lung fields
- D. Prominent vascular markings
Explanation: ***Air under the diaphragm*** - The presence of **free air** (pneumoperitoneum) beneath the diaphragm on an upright abdominal X-ray is a classic sign of **visceral perforation**. - A **tender and rigid abdomen** (peritoneal signs) indicates irritation of the peritoneum, most commonly due to a ruptured hollow viscus. *Blood under the diaphragm* - While blood can accumulate under the diaphragm (e.g., from **trauma** or a ruptured ectopic pregnancy), it typically manifests as a **hemoperitoneum** on imaging. - Blood is **fluid** and would appear as a fluid collection, not free air, on X-ray. *Hazy lung fields* - **Hazy lung fields** suggest conditions like **pulmonary edema**, pneumonia, or acute respiratory distress syndrome (ARDS). - These findings are primarily associated with pulmonary pathology and are not directly indicative of an acute abdominal emergency like perforation. *Prominent vascular markings* - **Prominent vascular markings** often indicate increased blood flow to the lungs or **pulmonary hypertension**. - This finding is unrelated to acute abdominal pain or peritoneal irritation.
Question 1333: Which of the following statements about lipoma is radiologically true?
- A. Low attenuation on CT scan (Correct Answer)
- B. Hyperechoic on ultrasound
- C. Hyperintense on fat-suppressed sequences
- D. Hyper-intense on T2-weighted MRI
Explanation: ***Low attenuation on CT scan*** - Lipomas, being composed of **fat**, appear as areas of **low attenuation** (typically -50 to -150 Hounsfield Units) on computed tomography (CT) scans. - This low attenuation is a **key diagnostic characteristic** that helps differentiate lipomas from other soft tissue masses. *Hyperechoic on ultrasound* - Lipomas typically appear **isoechoic to hypoechoic** on ultrasound, not consistently hyperechoic. - They may have a thin echogenic capsule, but the internal contents are usually similar to or less echogenic than adjacent subcutaneous fat. *Hyperintense on fat-suppressed sequences* - This is **incorrect** - lipomas show **signal dropout** (become dark/hypointense) on fat-suppressed sequences (STIR, fat-sat T1/T2). - Signal suppression on fat-saturated sequences is actually a **diagnostic feature** confirming the fatty nature of the lesion. - Note: Lipomas ARE hyperintense on standard T1-weighted imaging due to fat content. *Hyper-intense on T2-weighted MRI* - Lipomas typically show **intermediate to slightly hyperintense signal** on T2-weighted MRI, but not markedly hyperintense like fluid. - They are less bright than fluid-filled structures or highly vascular lesions on T2-weighted sequences.
Question 1334: Which of the following X-ray findings is associated with Chilaiditi syndrome?
- A. Pseudopneumoperitoneum (Correct Answer)
- B. Pseudopneumothorax
- C. Pneumothorax
- D. Hydropneumothorax
Explanation: ***Pseudopneumoperitoneum*** - Chilaiditi syndrome is characterized by the **interposition of a loop of colon (usually transverse colon) or, less commonly, small intestine** between the liver and the right hemidiaphragm. - This anatomical variation can mimic **free air under the diaphragm** on an X-ray, leading to the misdiagnosis of pneumoperitoneum. *Pseudopneumothorax* - This term describes the appearance of **air in the pleural space** that is not actually present, which is not associated with Chilaiditi syndrome. - While Chilaiditi syndrome involves misinterpretation of air, it specifically relates to the **abdominal cavity**, not the thoracic cavity. *Pneumothorax* - A **true pneumothorax** is the presence of air in the pleural cavity causing partial or complete lung collapse, which is a significant medical emergency. - It is distinct from Chilaiditi syndrome, which involves **abdominal content displacement** mimicking abdominal free air. *Hydropneumothorax* - This condition involves the presence of both **fluid and air in the pleural cavity**. - It is a pathology of the thoracic cavity and has **no direct association** with the abdominal interposition of bowel loops seen in Chilaiditi syndrome.
Question 1335: Which of the following is NOT a typical ultrasonographic finding in autosomal recessive polycystic kidney disease (ARPKD)?
- A. Increased echogenicity
- B. Cysts larger than 2 cm (Correct Answer)
- C. Enlarged kidneys
- D. Corticomedullary differentiation is lost
Explanation: **Cysts larger than 2 cm** - **ARPKD** is characterized by numerous tiny cysts (typically 1-2 mm, rarely up to 1 cm) that are microscopically dilated collecting ducts, leading to diffuse renal enlargement. - Cysts larger than 2 cm are much more typical of **autosomal dominant polycystic kidney disease (ADPKD)**, which involves macroscopic cysts of various sizes. *Enlarged kidneys* - The proliferation of dilated collecting ducts and associated interstitial fibrosis in **ARPKD** leads to significantly enlarged kidneys, which is a hallmark ultrasound finding. - This enlargement is often bilateral and can be detected prenatally or in neonates. *Increased echogenicity* - The presence of numerous tiny cysts and dense fibrous tissue throughout the renal parenchyma in **ARPKD** causes increased diffuse echogenicity on ultrasound. - This is a common and important diagnostic feature, often described as "bright" or "hyperechoic" kidneys. *Corticomedullary differentiation is lost* - In **ARPKD**, the normal distinct differentiation between the renal cortex and medulla is obliterated due to the widespread involvement of the collecting ducts and the diffuse nature of the disease. - This loss of corticomedullary differentiation is a typical finding on ultrasound for severe renal parenchymal disease, including ARPKD.
Surgery
1 questionsA patient presents with abdominal pain. On physical examination there was abdominal guarding and tenderness. A plain erect chest X-ray reveals air under diaphragm. Probable diagnosis is
NEET-PG 2015 - Surgery NEET-PG Practice Questions and MCQs
Question 1331: A patient presents with abdominal pain. On physical examination there was abdominal guarding and tenderness. A plain erect chest X-ray reveals air under diaphragm. Probable diagnosis is
- A. Perforated abdominal viscus (Correct Answer)
- B. Acute myocardial infarction
- C. Aortic dissection
- D. None of the options
Explanation: ***Perforated abdominal viscus*** - The presence of **abdominal guarding** and **tenderness** indicates peritoneal irritation, while **air under the diaphragm** on an erect chest X-ray (**pneumoperitoneum**) is a classic sign of a perforated hollow abdominal organ. - This combination strongly suggests a **perforated abdominal viscus**, such as a **perforated peptic ulcer** or perforated diverticulitis, leading to the leakage of air and intestinal contents into the peritoneal cavity. *Acute myocardial infarction* - Acute myocardial infarction primarily presents with **chest pain**, radiation to the arm/jaw, and shortness of breath, not typically severe abdominal pain with guarding. - While it can cause some epigastric discomfort, it would not explain the **pneumoperitoneum** seen on the chest X-ray. *Aortic dissection* - Aortic dissection typically causes **sudden, severe tearing chest or back pain**, often radiating to the back. - There is no direct link between aortic dissection and **air under the diaphragm** unless there's a co-existing, unrelated issue, which is not suggested by the primary symptoms. *None of the options* - Given the clear clinical and radiological findings of **pneumoperitoneum** and **peritoneal signs**, a perforated abdominal viscus is the most fitting diagnosis among the choices provided. - This option is incorrect as there is a highly probable diagnosis among the given choices.