NEET-PG 2020 Practice Questions

Q: The upward extension of thyroid swelling is prevented by which of the following structures

Pretracheal fascia. ***Pretracheal fascia*** - The **pretracheal fascia** is a deep cervical fascia layer that **envelops the thyroid gland** and is continuous with the fibrous capsule of the gland. - Due to its attachments, particularly to the **cricoid cartilage** and **recurrent laryngeal nerve sheath**, it anchors the thyroid gland and **restricts its upward movement** during swallowing. *Sternothyroid* - The **sternothyroid muscle** depresses the larynx and thyroid gland, but it does **not inherently prevent upward extension** of a thyroid swelling. - Its action is on the **movement of the larynx** and thyroid, rather than an anatomical barrier to swelling. *Thyrohyoid membrane* - The **thyrohyoid membrane** connects the thyroid cartilage to the hyoid bone and allows for movement between them, but it has no direct role in **preventing upward extension of a thyroid swelling**. - It is mainly involved in **laryngeal elevation** during swallowing. *Ligament of Berry* - The **ligament of Berry** (or lateral suspensory ligament) connects the thyroid gland to the **cricoid cartilage** and **trachea** [1]. - While it offers some stability to the thyroid gland, its primary role is to **anchor the gland posteriorly** rather than prevent the upward extension of a swelling [1].

Q: NO is synthesized from:

L-arginine. ***L-arginine*** - **Nitric oxide (NO)** is synthesized from the amino acid **L-arginine** by the enzyme **nitric oxide synthase (NOS)**. - This reaction requires **molecular oxygen** and **NADPH** as cofactors, producing **L-citrulline** as a co-product. - **Three NOS isoforms** exist: neuronal (nNOS), inducible (iNOS), and endothelial (eNOS). - **Clinical significance**: NO is crucial for **vascular smooth muscle relaxation**, **neurotransmission**, and **immune defense**. *L-citrulline* - **L-citrulline** is the co-product (not precursor) of the NO synthesis reaction. - While it can be recycled back to **L-arginine** via the **citrulline-arginine cycle**, it does not directly yield NO without first being converted to arginine. - This recycling pathway helps sustain NO production in endothelial cells. *Glycine* - **Glycine** is involved in various metabolic processes, including **heme synthesis**, **purine synthesis**, and as a neurotransmitter. - It plays no direct role in **nitric oxide** biosynthesis. - Not a substrate for any **NOS isoform**. *Lysine* - **Lysine** is an essential amino acid important for **protein synthesis**, **collagen formation**, and **carnitine synthesis**. - It is structurally distinct from arginine and is not recognized by **nitric oxide synthase**. - Not involved in the NO synthesis pathway.

Q: A farmer presented with a black mole on the cheek. It increased in size, more than 6mm with irregular borders and a central black lesion, what could be the diagnosis?

Superficial spreading melanoma. ***Superficial spreading melanoma*** - This is the most common type of melanoma and often presents as a **mole with irregular borders**, varying colors, and a diameter greater than 6mm, consistent with the description. - The lesion typically grows **radially** across the skin surface before beginning vertical growth, indicated by the increase in size. *Acral lentigo melanoma* - This type of melanoma primarily affects the **palms, soles, and nail beds**, which is inconsistent with a lesion on the cheek. - It often appears as a **dark brown or black patch** that slowly enlarges, but its location is characteristic. *Lentigo maligna melanoma* - This melanoma typically occurs in **chronically sun-damaged skin** of the elderly, often on the head and neck, but usually presents as a **flat, irregularly shaped, tan or brown patch** with varying shades, which may not fit the description of a central black lesion within a larger mole. - It has a dominant **radial growth phase** and progresses slowly over many years before developing a nodular component. *Nodular melanoma* - This type is characterized by its **rapid vertical growth** and appearance as a **raised, dark, often dome-shaped lesion** from the outset. - While it can be black, the description of an "increased in size" mole with irregular borders and a central black lesion points more towards a spreading type rather than a rapidly growing nodule from the beginning.

Q: Dermatological manifestation of which of the following diseases?

Pellagra. ***Pellagra*** - The image shows **Casal's necklace**, a characteristic **hyperpigmented, scaly, photosensitive rash** around the neck area, which is pathognomonic for pellagra. - Pellagra is caused by **niacin (vitamin B3) deficiency** and presents with the classic "4 D's": **dermatitis**, **diarrhea**, **dementia**, and **death** if untreated. *Acrodermatitis enteropathica* - This is a **hereditary zinc deficiency disorder** that presents with **periorificial and acral dermatitis** (around body openings and extremities). - The skin lesions are typically **vesiculobullous or eczematous** with a different distribution pattern, not the characteristic neck involvement seen here. *Photo dermatitis* - This is a **general term** for skin inflammation caused by **light exposure** and not a specific disease entity. - While pellagra does cause photosensitive dermatitis, photodermatitis alone doesn't explain the specific **necklace-like distribution** and underlying nutritional deficiency. *Vitamin B deficiency* - This option is **too broad** and non-specific, as it encompasses multiple B vitamin deficiencies with different manifestations. - Other B vitamin deficiencies like **B2 (riboflavin)** or **B6 (pyridoxine)** cause **angular cheilitis** and **seborrheic dermatitis**, not the characteristic neck rash of pellagra.

Q: As per POCSO act, child was brought for age estimation. Xray wrist taken. The maximum age of the wrist joint is:

13 years. ***13 years*** - In forensic age estimation using wrist X-rays, **13 years** represents a critical milestone where most carpal bones are fully ossified and the distal radius and ulna epiphyses are present but approaching fusion. - At this age, the **pisiform** (last carpal bone to appear, around 9-12 years) is typically visible, and epiphyseal fusion patterns help distinguish from younger ages. - The Greulich-Pyle atlas uses wrist X-rays for age estimation up to skeletal maturity, and 13 years shows characteristic near-complete carpal ossification. *7 years* - At 7 years, several carpal bones would still be in the process of ossification, with the **capitate, hamate, triquetrum, and lunate** typically visible, but the trapezium, trapezoid, scaphoid, and pisiform may be absent or incompletely ossified. - The distal radius and ulna epiphyses would be clearly separated from the metaphysis with wide growth plates. *10 years* - At 10 years, most carpal bones are present except possibly the **pisiform** (appears 9-12 years), and the distal radius and ulna epiphyses show clear separation from the shaft. - The epiphyseal gaps would be more prominent compared to a 13-year-old wrist. *4 years* - At 4 years, only a few carpal bones are ossified, typically the **capitate and hamate**, with the lunate possibly beginning to appear. - The epiphyses of the distal radius and ulna would be small and widely separated from the metaphysis, and metacarpal/phalangeal epiphyses would be less developed.

Q: A 32-year-old patient with Restless leg syndrome comes to the OPD. What is the most appropriate first line treatment?

Gabapentin. ***Gabapentin*** - **Gabapentin** and other alpha-2-delta ligands (e.g., pregabalin) are considered **first-line agents** for moderate to severe Restless Legs Syndrome (RLS), particularly when symptoms are bothersome and daily. - They work by modulating **calcium channels** and are effective in reducing RLS symptoms with a generally favorable side effect profile. *Iron Supplementation* - **Iron supplementation** is appropriate as first-line treatment only if **serum ferritin levels** are below 75 mcg/L, indicating iron deficiency. - While RLS is associated with **iron deficiency**, it's not the universal first-line treatment without biochemical confirmation [1]. *Pramipexole* - **Dopamine agonists** like pramipexole are effective for RLS but are generally **second-line treatments** due to concerns about augmentation (worsening of RLS symptoms) and impulse control disorders. - Augmentation is a significant side effect where symptoms worsen paradoxically with continued use, particularly with higher doses. *Vitamin B12* - **Vitamin B12 deficiency** can cause neurological symptoms, but it is **not a primary cause or treatment** for Restless Legs Syndrome. - Supplementation with **Vitamin B12** would only be considered if a confirmed deficiency exists, which is not stated as a contributing factor in this patient.

Q: Superior temporal gyrus lesion leads to?

Wernicke's aphasia. ***Wernicke's aphasia*** - A lesion in the **superior temporal gyrus** (Wernicke's area) leads to Wernicke's aphasia, characterized by impaired **comprehension of language** [1]. - Patients with Wernicke's aphasia exhibit **fluent but meaningless speech** (word salad) and are often unaware of their deficits [1]. *Anomic aphasia* - Characterized by difficulty finding words, particularly nouns and verbs, and is often associated with lesions in the **angular gyrus** or **temporal lobe** [1]. - Speech remains fluent and grammatically correct, but it is marked by frequent pauses and circumlocutions as the individual struggles to retrieve specific words. *Broca's aphasia* - Results from damage to **Broca's area** in the posterior inferior frontal gyrus, causing **non-fluent speech** and difficulty with speech production [1]. - While comprehension is relatively preserved, patients struggle to form complete sentences and may exhibit agrammatism. *Non-fluent aphasia* - A broad category of aphasias, including Broca's aphasia, where speech production is notably impaired, and the output is effortful and characterized by **agrammatism** and **short, telegraphic sentences**. - **Wernicke's aphasia** is typically considered a **fluent aphasia**, as speech production itself is not interrupted, though its content is often incomprehensible [1].

Q: Which is the most common site of gastrinoma in MEN 1 syndrome?

Duodenum. ***Duodenum*** - In **MEN 1 syndrome**, gastrinomas (gastrin-secreting tumors) are most commonly found in the **duodenum**, often multiple and small. - This location accounts for a significant majority of gastrinomas, particularly in patients with **Zollinger-Ellison syndrome (ZES)** associated with MEN 1. *Stomach* - While gastrinomas can occasionally be found in the stomach, this is a **much less common site** compared to the duodenum, especially in the context of MEN 1 syndrome. - Gastric gastrinomas are typically associated with conditions like **atrophic gastritis** and **pernicious anemia**, leading to G-cell hyperplasia and often hypergastrinemia, but tend to be less aggressive. *Ileum* - The **ileum** is an **uncommon site** for gastrinomas; these types of neuroendocrine tumors (NETs) are rarely found there. - NETs in the ileum are more typically associated with the secretion of other hormones, such as **serotonin**, leading to carcinoid syndrome, rather than gastrin. *Jejunum* - Gastrinomas in the **jejunum** are also **rare**, similar to the ileum. - While neuroendocrine tumors can arise throughout the small bowel, the jejunum is not a typical or primary location for gastrin-producing tumors within the context of **MEN 1**.

Q: Nosocomial infections are diagnosed after how many hours of hospitalization / admission?

48 hours. ***48 hours*** - Nosocomial infections, also known as **hospital-acquired infections (HAIs)**, are defined as infections that develop at least **48 hours** after hospital admission. - This time frame helps differentiate infections acquired in the hospital setting from those the patient was incubating upon admission. *96 hours* - A 96-hour threshold is **too long** for the standard definition of a nosocomial infection. - Infections emerging after this extended period would almost certainly be considered hospital-acquired, but the conventional diagnostic window is shorter. *72 hours* - While 72 hours might capture many HAIs, it is **not the universally accepted or most common cutoff** for defining a nosocomial infection. - The 48-hour mark is more widely used for epidemiological and diagnostic purposes. *24 hours* - Infections diagnosed within **24 hours** of admission are typically considered to have been present or incubating **prior to hospitalization**. - This short timeframe is generally insufficient to classify an infection as hospital-acquired.

Q: Loss of foot processes seen on electron microscopy of renal biopsy is a classical feature in which of the following?

Minimal change disease. ***Minimal change disease*** - **Loss of foot processes** (podocyte effacement) is the hallmark ultrastructural finding in **minimal change disease** on electron microscopy [1]. - This effacement of podocyte foot processes leads to increased permeability of the **glomerular filtration barrier** to albumin, causing **nephrotic syndrome** [1], [2]. *IgA nephropathy* - Characterized by **IgA immune complex deposition** in the **mesangium** on immunofluorescence. - Electron microscopy typically shows **mesangial immune deposits**, not primarily foot process effacement. *Membranous nephropathy* - Identified by the presence of **subepithelial immune deposits** and **thickening of the glomerular basement membrane** (GBM) [3]. - On electron microscopy, these deposits are visible, often with overlying **spikes** of GBM material separating them. *Rapidly progressive glomerulonephritis* - Defined by the rapid loss of renal function and the presence of **crescents** in more than 50% of glomeruli on light microscopy [2]. - While there may be secondary podocyte changes due to severe inflammation, **foot process effacement** is not its primary diagnostic feature. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. The Kidney, pp. 927-928. [2] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Diseases Of The Urinary And Male Genital Tracts, pp. 527-528. [3] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Diseases Of The Urinary And Male Genital Tracts, pp. 532-533.

Question 1

The upward extension of thyroid swelling is prevented by which of the following structures

Accepted Answer

Pretracheal fascia

Answer

Sternothyroid

Answer

Thyrohyoid membrane

Answer

Ligament of berry

Question 2

NO is synthesized from:

Accepted Answer

L-arginine

Answer

L-citrulline

Answer

Glycine

Answer

Lysine

Question 3

A farmer presented with a black mole on the cheek. It increased in size, more than 6mm with irregular borders and a central black lesion, what could be the diagnosis?

Accepted Answer

Superficial spreading melanoma

Answer

Acral lentigo melanoma

Answer

Lentigo maligna melanoma

Answer

Nodular melanoma

Question 4

Dermatological manifestation of which of the following diseases?

Accepted Answer

Pellagra

Answer

Photo dermatitis

Answer

Acrodermatitis enteropathica

Answer

Vitamin B deficiency

Question 5

As per POCSO act, child was brought for age estimation. Xray wrist taken. The maximum age of the wrist joint is:

Accepted Answer

13 years

Answer

7 years

Answer

10 years

Answer

4 years

Question 6

A 32-year-old patient with Restless leg syndrome comes to the OPD. What is the most appropriate first line treatment?

Accepted Answer

Gabapentin

Answer

Iron Supplementation

Answer

Pramipexole

Answer

Vitamin B12

Question 7

Superior temporal gyrus lesion leads to?

Accepted Answer

Wernicke's aphasia

Answer

Anomic aphasia

Answer

Broca's aphasia

Answer

Non-fluent aphasia

Question 8

Which is the most common site of gastrinoma in MEN 1 syndrome?

Accepted Answer

Duodenum

Answer

Stomach

Answer

Ileum

Answer

Jejunum

Question 9

Nosocomial infections are diagnosed after how many hours of hospitalization / admission?

Accepted Answer

48 hours

Answer

96 hours

Answer

72 hours

Answer

24 hours

Question 10

Loss of foot processes seen on electron microscopy of renal biopsy is a classical feature in which of the following?

Accepted Answer

Minimal change disease

Answer

Membranous nephropathy

Answer

Rapidly progressive glomerulonephritis

Answer

IgA nephropathy

NEET-PG 2020

Anatomy

Biochemistry

Dermatology

Forensic Medicine

Internal Medicine

Microbiology

Pathology