NEET-PG 2025 Practice Questions

Q: During hyperextension, the long head of triceps gets detached from which site?

Infraglenoid tubercle. ***Infraglenoid tubercle*** - The **long head of the triceps brachii** muscle originates from the **infraglenoid tubercle** of the scapula. - Violent or sudden hyperextension of the shoulder places maximum tensile stress on this specific origin site, predisposing it to avulsion or detachment. *Supraglenoid tubercle* - This tubercle is the origin point for the **long head of the biceps brachii** muscle, which is not the muscle relevant to this injury scenario. - Injuries involving the supraglenoid tubercle are classically associated with **SLAP lesions** and glenohumeral instability. *Shaft of humerus* - The **medial and lateral heads** of the triceps originate along the posterior surface of the shaft of the humerus. - These muscular origins are less prone to acute avulsion during hyperextension compared to the tendinous long head origin on the scapula. *Olecranon process* - The olecranon process of the ulna is the **insertion** point for all three heads of the triceps, not the origin. - Detachment at this site typically occurs due to direct impact or strong eccentric contraction during forced elbow flexion, often resulting in an **olecranon fracture**.

Q: A patient with HIV is newly diagnosed with multidrug-resistant tuberculosis. Which of the following is the appropriate regimen, and what should the patient be monitored for?

BPaLM; monitor for immune reconstitution syndrome. ***BPaLM; monitor for immune reconstitution syndrome*** - The **BPaLM** regimen (Bedaquiline, Pretomanid, Linezolid, Moxifloxacin/Levofloxacin) is the recommended all-oral, shorter course (6-9 months) treatment for confirmed drug-resistant or **MDR/RR-TB** (Multidrug/Rifampicin-resistant TB). - HIV co-infected patients are at high risk for **Immune Reconstitution Inflammatory Syndrome (IRIS)**, a paradoxical immune reaction that occurs upon starting effective TB treatment, especially after initiating or optimizing **ART** (Antiretroviral Therapy) [2]. *INH + Levofloxacin + Pyrazinamide + Ethambutol, monitor for hepatotoxicity* - This regimen is inappropriate for **MDR-TB** because it contains **Isoniazid (INH)**, to which the patient's strain is resistant by definition. - While monitoring for **hepatotoxicity** (especially due to Pyrazinamide and INH) is crucial in general TB management, this combination lacks the necessary potent second-line agents. *INH + Levofloxacin + Streptomycin + Ethionamide, monitor for pyridoxine deficiency* - This regimen includes **INH** and older, more toxic second-line drugs like **Streptomycin** (an injectable agent now largely avoided) and **Ethionamide**. - Monitoring for **pyridoxine (Vitamin B6) deficiency** is necessary when using drugs like INH or Ethionamide, but the overall regimen is considered outdated and suboptimal for standard MDR-TB management [1]. *INH + Clarithromycin + Pyrazinamide + Ethambutol, monitor for optic neuritis* - This regimen is incorrect because it contains **INH** (ineffective in MDR-TB) and **Clarithromycin**, which is primarily used for **MAC** (Mycobacterium avium complex) and not a core drug for *M. tuberculosis*. - Although monitoring for **optic neuritis** is specific to **Ethambutol** toxicity, the inclusion of inappropriate drugs makes this an unsuitable MDR-TB treatment combination.

Q: A patient with paroxysmal supraventricular tachycardia (PSVT) requires treatment for prophylaxis. Which drug is appropriate?

Oral verapamil. ***Verapamil*** - It is an oral **non-dihydropyridine calcium channel blocker** commonly used for long-term **prophylaxis** of recurrent PSVT (AVNRT/AVRT) by slowing conduction through the AV node [1], [2]. - It is effective for reducing the frequency of episodes and achieving chronic **rate and rhythm control** in stable patients [1]. *IV adenosine* - Adenosine is the drug of choice for the **acute termination** of PSVT due to its rapid onset and extremely short half-life, making it unsuitable for chronic long-term **prophylaxis** [2]. - It works by transiently blocking the **AV node** conduction [2]. *IV esmolol* - Esmolol is an ultra-short-acting **beta-blocker** administered intravenously, primarily used for **acute control** of heart rate or rhythm in emergency settings [3]. - Since the requirement is for prophylaxis, an oral formulation (e.g., oral metoprolol) would be preferred over an **intravenous agent** [3]. *Oral phenytoin* - Phenytoin is mainly an anti-epileptic and is historically reserved for the treatment of **digitalis-induced ventricular arrhythmias**. - It is **not a standard or primary agent** recommended by current guidelines for the long-term prophylactic management of typical non-digitalis-induced PSVT.

Q: Group A Streptococcus is the most common cause of bacterial pharyngitis in school-aged children. Which of the following bacterial components is primarily responsible for its attachment to fibronectin on the epithelial lining of the pharynx?

Lipoteichoic acid. ***Lipoteichoic acid*** - **Lipoteichoic acid (LTA)**, along with the **M protein**, serves as a key adhesin for Group A Streptococcus, mediating attachment by binding to **fibronectin** receptors on pharyngeal epithelial cells. - This adherence mechanism is essential for the initial colonization and subsequent establishment of **streptococcal pharyngitis**. *Lipoprotein* - **Lipoproteins** are structurally diverse cell components, but they are not recognized as the primary molecular component mediating the specific attachment of GAS to **fibronectin**. - They often reside in the cell membrane and typically function in **nutrient transport** or signaling pathways. *Capsule* - The **hyaluronic acid capsule** of Group A Streptococcus mainly functions as an **anti-phagocytic factor** against host immune cells, preventing ingestion. - While important for virulence, it is not the molecule that directly facilitates initial adherence to the **fibronectin** layer of the host epithelium. *Flagella* - **Flagella** are organelles primarily responsible for **bacterial motility** (movement). - *Streptococcus pyogenes* (Group A Streptococcus) is a **non-motile** organism and therefore lacks flagella.

Q: In a village, several people developed dysentery after consuming raw milk. On laboratory examination, gram-negative, curved rods with polymorphonuclear infiltration were found in stool samples. Which of the following is the most likely causative organism?

Campylobacter jejuni. ***Campylobacter jejuni*** - This organism is a **Gram-negative, curved or S-shaped rod** (seagull appearance) that causes inflammatory diarrhea (**dysentery**) and is the most common antecedent of **Guillain-Barré Syndrome**. - The association of dysentery with consumption of **raw milk** is a classic epidemiological feature of *C. jejuni* infection, explaining the outbreak. *Clostridium perfringens* - This is a **Gram-positive, spore-forming rod** and causes toxin-mediated food poisoning (Type A) characterized primarily by watery diarrhea, not typically dysentery. - The source is usually contaminated meat and gravies, and the stool sample would show a **Gram-positive rod**, not a curved Gram-negative rod. *Staphylococcus aureus* - This organism is a **Gram-positive coccus** that causes food intoxication with rapid onset vomiting being the prominent feature, not dysentery. - The pathology is preformed toxin-mediated, and stool analysis would reveal **cocci**, not curved rods, and lacks the PMN infiltration typical of dysentery. *Vibrio parahaemolyticus* - While it is a **Gram-negative curved rod**, it is strongly associated with the consumption of **raw or undercooked seafood**, especially shellfish. - Clinically, it usually causes watery diarrhea, and raw milk is not its typical vehicle of transmission for large outbreaks.

Q: A patient presents with low-grade fever, chronic cough, and weight loss. Fungal culture from respiratory secretions shows the following organism with characteristic tuberculate macroconidia on microscopy. What is the most likely diagnosis?

Histoplasmosis. ***Histoplasmosis*** - The image displayed shows characteristic large, spiny, thick-walled structures known as **tuberculate macroconidia**, which are pathognomonic for the mold phase of ***Histoplasma capsulatum*** grown at 25°C. - The clinical presentation of chronic cough, low-grade fever, and weight loss is typical of chronic pulmonary **Histoplasmosis** in immunocompetent individuals and often mimics tuberculosis. *Blastomycosis* - The yeast form of *Blastomyces dermatitidis* is characterized by having distinctive **broad-based budding** and large size (8-15 µm). - The mold phase of *Blastomyces* produces oval to pear-shaped microconidia on short or long stalks, not the tuberculate macroconidia seen in the picture. *Cryptococcosis* - *Cryptococcus neoformans* is a yeast encapsulated with a polysaccharide capsule and typically demonstrates smooth, **narrow-based budding** without forming true hyphae or macroconidia in culture. - Although it can cause pulmonary disease, its yeast morphology and lack of dimorphism differentiate it from the organism shown. *Coccidioidomycosis* - The mold form of *Coccidioides immitis* produces thin-walled, barrel-shaped structures called **arthroconidia**, which are highly infectious. - The tissue phase is defined by large **spherules containing endospores**, a morphology that is distinctly different from the tuberculate macroconidia shown.

Q: A male patient presents with fever, cough, and hemoptysis. Bronchoalveolar lavage (BAL) fluid examination shows septate hyphae with acute angle (dichotomous) branching under microscopy. What is the most likely diagnosis?

Aspergillosis. ***Aspergillosis*** - The characteristic finding of **septate hyphae** displaying uniform **acute angle (dichotomous) branching** (typically 45°) in the **Bronchoalveolar lavage (BAL)** fluid is the defining microscopic feature of *Aspergillus* infection [1], [2]. - The clinical picture of fever, cough, and **hemoptysis** suggests an invasive pulmonary fungal infection, which *Aspergillus* commonly causes, especially in immunocompromised hosts [1], [2]. *Mucormycosis* - This diagnosis is characterized by **broad, non-septate (aseptate) hyphae** that exhibit irregular branching, typically at a **wide angle (90°)**. - The absence of septae and the differing angle of branching rule out mucormycosis based on the microscopic findings. *Histoplasmosis* - *Histoplasma capsulatum* appears in tissue and BAL primarily as **small, oval, budding yeast forms** (2–4 µm) that are often **intracellular** within macrophages. - It is not a hyphal infection in tissue form and therefore does not show septate hyphae with dichotomous branching. *Candidiasis* - *Candida* is identified by the presence of both **budding yeast cells** and **pseudohyphae** (links of elongated yeast cells) [2]. - Although true septate hyphae can occasionally be seen, it lacks the highly characteristic, uniform **acute-angle dichotomous branching** that is specific to *Aspergillus*. **References:** [1] Kumar V, Abbas AK, et al.. Robbins and Cotran Pathologic Basis of Disease. 9th ed. Infectious Diseases, pp. 396-397. [2] Cross SS. Underwood's Pathology: A Clinical Approach. 6th ed. Common Clinical Problems From Respiratory Tract Disease, pp. 318-319.

Q: A young adult presents with facial pain and painful vesicular lesions in the mouth. Tzanck smear reveals multinucleated giant cells with intranuclear inclusions. What is the most likely causative organism?

Herpes simplex virus. ***Herpes simplex virus*** - The presentation of **painful vesicular lesions** in the mouth and **facial pain** strongly suggests primary (e.g., gingivostomatitis) or reactivated herpes infection. - The **Tzanck smear** showing **multinucleated giant cells** with **intranuclear inclusions** is characteristic of the Herpesviridae family, confirming the clinical suspicion of HSV. *Adenovirus* - Adenovirus typically causes **pharyngoconjunctival fever**, acute respiratory disease, or viral conjunctivitis, not localized vesicular lesions in the mouth. - It does not produce the hallmark cytopathic effect of **multinucleated giant cells** on Tzanck smear. *Cytomegalovirus* - CMV usually presents as a mild **mononucleosis-like syndrome** in healthy adults or causes severe systemic disease in the immunocompromised. - CMV histology is defined by large intranuclear **"owl's eye" inclusions**, a finding different from the multinucleated giant cells seen on Tzanck smear. *Epstein-Barr virus* - EBV causes **Infectious Mononucleosis**, characterized by fever, lymphadenopathy, and pharyngitis, not primarily painful vesicular eruptions. - Although part of the herpes family, EBV typically causes unique lymphoid pathology and **Hairy Leukoplakia**, not the cytopathic changes seen on Tzanck smear.

Q: A woman diagnosed with migraine has a family history of coronary artery disease. What is the drug of choice for migraine prophylaxis?

Propranolol. ***Propranolol*** - **Propranolol** is a first-line drug for migraine prophylaxis, particularly favored in patients with co-existing conditions like hypertension, anxiety, or, as in this case, risk factors for **Coronary Artery Disease (CAD)**. - As a non-selective beta-blocker, it provides effective migraine prevention while potentially offering **cardioprotective benefits**, making it the safest and best choice here. *Topiramate* - **Topiramate** is also a first-line prophylactic agent, but it is often preferred when patients need to avoid weight gain or have co-existing seizure disorders. - It has no particular advantage over propranolol in lowering cardiac risk and is associated with common side effects such as cognitive impairment (**'fogginess'**) and **nephrolithiasis**. *Ergotamine* - **Ergotamine preparations** are severe vasoconstrictors and are used primarily for the **acute termination** of migraine attacks, not for long-term prophylaxis. - They are absolutely **contraindicated** in patients with established or high risk of **Coronary Artery Disease** (CAD) due to the risk of **myocardial infarction** and stroke. *Amitriptyline* - **Amitriptyline** (a TCA) is used for prophylaxis, especially in patients with co-existing **insomnia** or chronic **tension headaches**. - While effective, TCAs can have potential **cardiac side effects** (e.g., QTc prolongation, orthostatic hypotension) which makes **propranolol** a medically safer choice for patients with a family history of CAD.

Q: A patient is started on hydrochlorothiazide for hypertension and later develops renal stones. Which metabolic effect of hydrochlorothiazide is most likely responsible?

Hyperuricemia. ***Hyperuricemia*** * Hydrochlorothiazide causes **hyperuricemia** by competing with uric acid for secretion in the proximal tubule, leading to decreased uric acid excretion. * Elevated serum uric acid levels increase the risk of **uric acid stone formation**, which is a well-recognized adverse effect of thiazide diuretics. * This is why thiazides can precipitate gout attacks and increase uric acid stone risk. *Hypocalciuria* * HCTZ causes **decreased urinary calcium excretion** (hypocalciuria) by enhancing calcium reabsorption in the DCT. * This effect is **stone-PROTECTIVE**, not causative - thiazides are actually used therapeutically to prevent recurrent calcium stones. * This would NOT explain stone formation in this patient. *Hypomagnesemia* * While HCTZ can cause magnesium loss, hypomagnesemia is not a primary mechanism for stone formation with thiazide use. * Magnesium is actually a stone inhibitor, so low levels could theoretically contribute, but this is not the main mechanism. *Hypocitraturia* * HCTZ does not typically cause significant citrate wasting or hypocitraturia. * Hypocitraturia is more characteristic of **carbonic anhydrase inhibitors** and chronic metabolic acidosis, not thiazide diuretics.

Question 1

During hyperextension, the long head of triceps gets detached from which site?

Accepted Answer

Infraglenoid tubercle

Answer

Supraglenoid tubercle

Answer

Shaft of humerus

Answer

Olecranon process

Question 2

A patient with HIV is newly diagnosed with multidrug-resistant tuberculosis. Which of the following is the appropriate regimen, and what should the patient be monitored for?

Accepted Answer

BPaLM; monitor for immune reconstitution syndrome

Answer

INH + Levofloxacin + Pyrazinamide + ethambutol, monitor for hepatotoxicity

Answer

INH + Levofloxacin + Streptomycin + Ethionamide, monitor for pyridoxine deficiency

Answer

INH + Clarithromycin + Pyrazinamide + Ethambutol, monitor for optic neuritis

Question 3

A patient with paroxysmal supraventricular tachycardia (PSVT) requires treatment for prophylaxis. Which drug is appropriate?

Accepted Answer

Oral verapamil

Answer

IV esmolol

Answer

Oral phenytoin

Answer

IV adenosine

Question 4

Group A Streptococcus is the most common cause of bacterial pharyngitis in school-aged children. Which of the following bacterial components is primarily responsible for its attachment to fibronectin on the epithelial lining of the pharynx?

Accepted Answer

Lipoteichoic acid

Answer

Capsule

Answer

Flagella

Answer

Lipoprotein

Question 5

In a village, several people developed dysentery after consuming raw milk. On laboratory examination, gram-negative, curved rods with polymorphonuclear infiltration were found in stool samples. Which of the following is the most likely causative organism?

Accepted Answer

Campylobacter jejuni

Answer

Staphylococcus aureus

Answer

Vibrio parahaemolyticus

Answer

Clostridium perfringens

Question 6

A patient presents with low-grade fever, chronic cough, and weight loss. Fungal culture from respiratory secretions shows the following organism with characteristic tuberculate macroconidia on microscopy. What is the most likely diagnosis?

Accepted Answer

Histoplasmosis

Answer

Cryptococcosis

Answer

Coccidioidomycosis

Answer

Blastomycosis

Question 7

A male patient presents with fever, cough, and hemoptysis. Bronchoalveolar lavage (BAL) fluid examination shows septate hyphae with acute angle (dichotomous) branching under microscopy. What is the most likely diagnosis?

Accepted Answer

Aspergillosis

Answer

Mucormycosis

Answer

Histoplasmosis

Answer

Candidiasis

Question 8

A young adult presents with facial pain and painful vesicular lesions in the mouth. Tzanck smear reveals multinucleated giant cells with intranuclear inclusions. What is the most likely causative organism?

Accepted Answer

Herpes simplex virus

Answer

Adenovirus

Answer

Cytomegalovirus

Answer

Epstein-Barr virus

Question 9

A woman diagnosed with migraine has a family history of coronary artery disease. What is the drug of choice for migraine prophylaxis?

Accepted Answer

Propranolol

Answer

Topiramate

Answer

Ergotamine

Answer

Amitriptyline

Question 10

A patient is started on hydrochlorothiazide for hypertension and later develops renal stones. Which metabolic effect of hydrochlorothiazide is most likely responsible?

Accepted Answer

Hyperuricemia

Answer

Hypocitraturia

Answer

Hypocalciuria

Answer

Hypomagnesemia

NEET-PG 2025

Anatomy

Internal Medicine

Microbiology

Pharmacology