Pulmonology — MCQs

Pulmonology Indian Medical PG Practice Questions and MCQs

Question 61: Proximal bronchiectasis, blood eosinophilia, and asthma are characteristic features of which condition?

A. Histoplasmosis
B. Measles
C. Allergic bronchopulmonary aspergillosis (Correct Answer)
D. Tuberculosis

Explanation: The correct answer is **Allergic Bronchopulmonary Aspergillosis (ABPA)**. ABPA is a complex hypersensitivity reaction (Type I and Type III) to *Aspergillus fumigatus* colonization in the airways, occurring almost exclusively in patients with **Asthma** or **Cystic Fibrosis** [1]. **Why ABPA is correct:** The diagnosis is based on a constellation of clinical and radiological findings. The presence of **asthma**, **peripheral blood eosinophilia**, and **proximal (central) bronchiectasis** are hallmark features [2]. In ABPA, the immune system reacts to fungal antigens, leading to mucus plugging in the central bronchi. This results in the characteristic "finger-in-glove" appearance on imaging and subsequent permanent dilation of the proximal airways [2]. **Why other options are incorrect:** * **Histoplasmosis:** A fungal infection caused by *Histoplasma capsulatum*, typically presenting as a granulomatous lung disease (similar to TB) or mediastinal lymphadenopathy, not typically associated with asthma or proximal bronchiectasis. * **Measles:** While measles can cause severe viral pneumonia or late-onset bronchiectasis (usually follicular), it does not present with eosinophilia or asthma. * **Tuberculosis:** TB is a common cause of **traction bronchiectasis** (usually in the upper lobes), but it is an infectious process characterized by granulomatous inflammation, not eosinophilic hypersensitivity [2]. **High-Yield Clinical Pearls for NEET-PG:** * **Radiology:** Look for "Finger-in-glove" opacities and "Tram-track" appearance. * **Laboratory:** Elevated **Total Serum IgE** (>1000 IU/mL) is a key screening criterion. * **Serology:** Specific IgE and IgG against *Aspergillus fumigatus* are elevated. * **Treatment:** The mainstay of treatment is **Oral Corticosteroids** to reduce inflammation, often combined with **Itraconazole** to reduce the fungal burden.

Question 62: Tuberculous pleural effusion is characterized by all, except?

A. LDH > 60% of serum LDH
B. Hemorrhagic fluid
C. Increased mesothelial cells (Correct Answer)
D. Increased adenosine deaminase

Explanation: Tuberculous pleural effusion (TPE) is a delayed hypersensitivity reaction to mycobacterial antigens entering the pleural space. Understanding its biochemical and cellular profile is crucial for NEET-PG. **Why "Increased mesothelial cells" is the correct answer (the exception):** In TPE, the pleural inflammation causes intense fibrin deposition and thickening of the visceral and parietal pleura. This layer of fibrin "coats" the pleural surfaces, preventing mesothelial cells from shedding into the fluid. Therefore, a **paucity of mesothelial cells (typically <5%)** is a hallmark of tuberculosis. If a pleural fluid sample shows many mesothelial cells, the diagnosis of TB is highly unlikely. **Analysis of other options:** * **LDH > 60% of serum LDH:** TPE is an **exudative effusion**. According to Light’s Criteria, an exudate must have a pleural fluid LDH to serum LDH ratio > 0.6 (60%). * **Hemorrhagic fluid:** While TPE is classically straw-colored, it can be serosanguinous or hemorrhagic in about 10-15% of cases [1]. It does not exclude the diagnosis. * **Increased Adenosine Deaminase (ADA):** ADA is a marker of T-cell activation. Since TPE is a T-cell mediated response, ADA levels are typically high (usually **>40 U/L**). This is a highly sensitive screening test. **High-Yield Clinical Pearls for NEET-PG:** 1. **Cellular Profile:** Early TPE may show neutrophils, but it characteristically evolves into **lymphocytic predominance** (>50-70%). 2. **Gold Standard:** Pleural biopsy (showing granulomas) has a higher yield than fluid culture or AFB staining. [2] 3. **Interferon-gamma:** High levels in pleural fluid are also diagnostic of TPE. 4. **Glucose:** Usually low to normal, but if very low (<60 mg/dL), it suggests a high bacterial burden or chronicity.

Question 63: Which interleukin is involved in asthma?

A. IL-5 (Correct Answer)
B. IL-1
C. IL-2
D. INF-alpha

Explanation: ### Explanation **Correct Answer: A. IL-5** **Mechanism and Pathophysiology:** Asthma is primarily a **Type 2 helper T cell (Th2)-mediated** inflammatory disease. When an allergen is encountered, Th2 cells release a specific profile of cytokines, most notably **IL-4, IL-5, and IL-13**. [1] * **IL-5** is the key cytokine responsible for the **recruitment, activation, and survival of eosinophils**. * Eosinophilic inflammation is a hallmark of "Th2-high" asthma, leading to airway hyperresponsiveness and tissue damage. [1] This clinical significance is highlighted by the use of monoclonal antibodies like **Mepolizumab** and **Reslizumab**, which target IL-5 to treat severe eosinophilic asthma. **Analysis of Incorrect Options:** * **B. IL-1:** This is a pro-inflammatory cytokine primarily involved in the innate immune response and acute phase reactions (fever). While it plays a role in general inflammation, it is not the primary driver of the specific Th2 pathway in asthma. * **C. IL-2:** Known as the T-cell growth factor, IL-2 is essential for the proliferation of all T-cell subsets and is more closely associated with acute transplant rejection and general lymphocyte activation rather than the specific allergic cascade of asthma. * **D. INF-alpha:** Interferon-alpha is an antiviral cytokine used in the treatment of Hepatitis B/C and certain malignancies. In fact, Type 1 interferons (like INF-alpha) often antagonize Th2 responses; a deficiency in interferon production is sometimes linked to increased susceptibility to viral-induced asthma exacerbations. **High-Yield Clinical Pearls for NEET-PG:** * **IL-4:** Responsible for B-cell class switching to **IgE** production. [1] * **IL-13:** Stimulates **mucus hypersecretion** and bronchial hyperreactivity. * **Charcot-Leyden Crystals:** Formed from the breakdown of eosinophils (galectin-10) in asthmatic sputum. * **Curschmann Spirals:** Whorled mucus plugs seen in the sputum of asthma patients.

Question 64: What is the definitive diagnostic method for bronchial asthma?

A. Symptomatic relief following bronchodilator administration
B. Methacholine challenge test
C. A reduced FEV/FVC ratio on spirometry
D. Demonstration of reversible bronchial hyperresponsiveness (Correct Answer)

Explanation: **Explanation:** The hallmark of bronchial asthma is **reversible airway obstruction** and **bronchial hyperresponsiveness (BHR)**. While asthma is often suspected clinically, the definitive diagnosis requires objective evidence of variable airflow limitation [1]. **Why Option D is Correct:** The physiological definition of asthma relies on demonstrating that the airway narrowing is both exaggerated (hyperresponsiveness) and reversible. Reversibility is typically defined as an increase in FEV1 of **>12% and >200 mL** after inhaling a short-acting beta-agonist (SABA). This demonstration of "reversible BHR" distinguishes asthma from other obstructive lung diseases like COPD [1], [2]. **Analysis of Incorrect Options:** * **Option A:** While symptomatic relief with bronchodilators is clinically suggestive, it is subjective and can occur in other conditions (e.g., viral bronchiolitis or cardiac asthma). It does not provide the objective physiological data required for a definitive diagnosis. * **Option B:** The Methacholine challenge test is used to demonstrate BHR when spirometry is normal [2]. However, it has high sensitivity but **low specificity**, as positive results can occur in allergic rhinitis, cystic fibrosis, or COPD [2]. It is a "rule-out" test rather than the definitive "rule-in" method. * **Option C:** A reduced FEV1/FVC ratio (obstructive pattern) is seen in asthma, but it is also the hallmark of COPD and bronchiectasis [1]. Without demonstrating reversibility, this ratio alone cannot diagnose asthma. **NEET-PG High-Yield Pearls:** * **Gold Standard for Diagnosis:** Spirometry demonstrating reversibility [1]. * **Diurnal Variation:** A Peak Expiratory Flow (PEF) variability of **>10%** is also diagnostic [1]. * **FeNO (Fractional Exhaled Nitric Oxide):** Used to monitor eosinophilic airway inflammation, not for definitive diagnosis. * **Step-up Therapy:** If asthma is uncontrolled, always check **inhaler technique** and **compliance** before increasing medication.

Question 65: Which of the following can cause pleural fibrosis?

A. Phenytoin
B. Methysergide
C. Amiodarone (Correct Answer)
D. Ergotamine

Explanation: **Explanation:** The correct answer is **Amiodarone (Option C)**. Amiodarone is a Class III anti-arrhythmic drug known for its extensive side-effect profile, particularly involving the lungs [1]. It can cause a spectrum of pulmonary toxicities, including interstitial pneumonitis, organizing pneumonia, and **pleural thickening or fibrosis**. The mechanism involves both direct toxic effects on alveolar cells and an indirect immunological response, leading to the accumulation of phospholipids within lysosomes (phospholipidosis) [2]. Pleural involvement often manifests as pleuritic chest pain and localized thickening on imaging. **Analysis of Incorrect Options:** * **Phenytoin (A):** While phenytoin is associated with drug-induced systemic lupus erythematosus (DILE) and lymphadenopathy, it is not a classic cause of isolated pleural fibrosis. * **Methysergide (B) and Ergotamine (D):** These are ergot alkaloids. While they are classically associated with **retroperitoneal fibrosis**, they are more frequently linked to **pleural effusions** and pleuritis rather than primary pleural fibrosis in the context of modern clinical vignettes, where Amiodarone remains the higher-yield association for parenchymal and pleural scarring. **High-Yield Clinical Pearls for NEET-PG:** * **Amiodarone Toxicity:** Look for "foamy macrophages" in alveolar spaces on histopathology. It has a very long half-life (approx. 58 days), meaning toxicity can persist long after drug discontinuation. * **Drug-Induced Pleural Disease:** Other common culprits include Nitrofurantoin, Methotrexate, and Practolol [1]. * **Ergot Alkaloids:** Always associate Methysergide with the "Triad of Fibrosis": Retroperitoneal, Pleuropulmonary, and Endocardial (cardiac valves). * **Radiology:** Amiodarone-induced lung injury often shows high-attenuation (hyperdense) areas on CT due to the high iodine content of the drug.

Question 66: Which of the following is the least common bacterium responsible for acute exacerbation of chronic bronchitis?

A. Streptococcus pneumoniae
B. Moraxella catarrhalis
C. Haemophilus influenza
D. Staphylococcus aureus (Correct Answer)

Explanation: **Explanation:** Acute Exacerbation of Chronic Obstructive Pulmonary Disease (AECOPD) or Chronic Bronchitis is frequently triggered by bacterial infections. The pathophysiology involves an increase in airway inflammation and mucus production, often driven by specific respiratory pathogens. **Why Staphylococcus aureus is the correct answer:** While *Staphylococcus aureus* can cause pneumonia, it is a **rare** cause of simple acute exacerbations of chronic bronchitis [1]. It is generally only considered in specific contexts, such as post-viral (influenza) infections or in patients with severe structural lung damage (like bronchiectasis) [1]. In standard epidemiological studies of AECOPD, it consistently ranks as the least common among the listed options. **Analysis of Incorrect Options:** * **Haemophilus influenzae (Option C):** This is the **most common** bacterial pathogen isolated in patients with AECOPD. It is a gram-negative coccobacillus that colonizes the lower airways of smokers. * **Streptococcus pneumoniae (Option A):** This is the second or third most common cause. It is a classic gram-positive diplococcus [1] and a major target for vaccination in COPD patients. * **Moraxella catarrhalis (Option B):** This is a very common cause, particularly in elderly patients and those with long-standing COPD. It is a gram-negative diplococcus. **NEET-PG High-Yield Pearls:** * **Most common cause of AECOPD overall:** Viral infections (e.g., Rhinovirus). * **Most common bacterial cause:** *Haemophilus influenzae*. * **Winnipeg Criteria:** Used to define the severity of an exacerbation based on increased dyspnea, increased sputum volume, and increased sputum purulence. * **Antibiotic Choice:** Usually targets the "Big Three" (*H. influenzae, S. pneumoniae, M. catarrhalis*) using Macrolides, Cephalosporins, or Amoxicillin-Clavulanate.

Question 67: Which of the following conditions is associated with increased vocal resonance?

A. Empyema
B. Primary TB lung
C. Fibrosing alveolitis
D. Bronchial carcinoma (Correct Answer)

Explanation: **Explanation:** **Understanding Vocal Resonance:** Vocal resonance is the clinical equivalent of vocal fremitus, where the clinician listens for transmitted speech sounds through the chest wall. It is **increased** whenever lung tissue becomes more solid or dense (consolidation/collapse with a patent bronchus), as solid medium conducts sound waves more efficiently than air-filled alveoli. **Why Bronchial Carcinoma is Correct:** In **Bronchial Carcinoma**, a tumor can cause extrinsic compression or intrinsic obstruction leading to **obstructive collapse** of the distal lung segment [1]. If the bronchus remains partially patent or if the collapsed lung tissue becomes solid and airless, it acts as an excellent conductor of sound, leading to increased vocal resonance. Note: If the bronchus is completely obstructed, resonance would be absent; however, among the given options, carcinoma-associated consolidation/collapse is the most classic cause for increased resonance. **Why Other Options are Incorrect:** * **Empyema (A):** This is a collection of pus in the pleural space. Fluid (like air) acts as a barrier between the lung and the chest wall, **decreasing** or abolishing vocal resonance. * **Primary TB Lung (B):** Primary TB typically presents with a small Ghon focus and hilar lymphadenopathy. Unless it progresses to significant consolidation (which is more common in post-primary TB), it does not significantly alter resonance. * **Fibrosing Alveolitis (C):** Also known as Interstitial Lung Disease (ILD). While the lung is "stiff," the presence of diffuse interstitial thickening usually does not produce the same degree of sound conduction as lobar consolidation; resonance is typically normal or slightly decreased. **NEET-PG High-Yield Pearls:** * **Increased Vocal Resonance:** Seen in Consolidation (Pneumonia), Lung Cavity (large/superficial), and Collapse with a patent bronchus. * **Decreased Vocal Resonance:** Seen in Pleural effusion, Pneumothorax, Emphysema (hyperinflation), and Thickened pleura. * **Aegophony:** A nasal "bleating" quality of voice sounds (E to A change) heard at the upper border of a pleural effusion.

Question 68: Which of the following is true about Pneumothorax?

A. Decreased Chest Expansion (Correct Answer)
B. Increased Breath Sounds
C. Increased Vocal Resonance
D. Dull percussion note

Explanation: Pneumothorax occurs when air enters the pleural space, leading to the loss of negative intrapleural pressure and subsequent lung collapse [1]. **Why Option A is Correct:** In pneumothorax, the affected side of the chest is already in a state of relative expansion due to the presence of air in the pleural cavity. During inspiration, the collapsed lung cannot expand further, and the chest wall on that side shows **decreased or restricted movement/expansion** compared to the healthy side. **Why the other options are Incorrect:** * **B. Increased Breath Sounds:** In pneumothorax, the air in the pleural space acts as an insulator, preventing the transmission of sounds from the lung to the chest wall. Therefore, breath sounds are **absent or significantly diminished**. * **C. Increased Vocal Resonance:** Similar to breath sounds, the conduction of vibrations is interrupted by the air-filled pleural space. This leads to **decreased vocal resonance** and decreased vocal fremitus. (Increased resonance is seen in consolidation). * **D. Dull Percussion Note:** Air is less dense than lung tissue. Percussion over an air-filled pleural space yields a **hyper-resonant** note. A dull note is characteristic of fluid (pleural effusion) or solid mass (consolidation/collapse). **High-Yield Clinical Pearls for NEET-PG:** * **Tension Pneumothorax:** Look for hemodynamic instability, tracheal deviation to the *opposite* side, and distended neck veins [1]. It is a clinical diagnosis; do not wait for an X-ray [1]. * **Deep Sulcus Sign:** A classic radiological finding on a supine chest X-ray indicating pneumothorax. * **Management:** Small primary spontaneous pneumothorax (<2cm) may be managed conservatively; large or symptomatic cases require needle decompression (2nd ICS, mid-clavicular line) or chest tube insertion (5th ICS, anterior axillary line).

Question 69: For a patient with advanced chronic obstructive pulmonary disease (COPD), which nursing action best promotes adequate gas exchange?

A. Encouraging the patient to drink three glasses of fluid daily
B. Keeping the patient in semi-Fowler’s position
C. Using a high-flow Venturi mask to deliver oxygen as prescribed (Correct Answer)
D. Administering a sedative, as prescribed

Explanation: ### Explanation **Correct Option: C. Using a high-flow Venturi mask to deliver oxygen as prescribed** In advanced COPD, the primary goal of oxygen therapy is to correct hypoxemia without suppressing the patient's respiratory drive [1]. Patients with chronic hypercapnia often rely on **hypoxic drive** (low $PaO_2$) to stimulate breathing [2]. The **Venturi mask** is the preferred delivery system because it provides a precise, constant FiO2 regardless of the patient’s respiratory rate or pattern. This prevents the administration of excessive oxygen, which could lead to CO2 retention and respiratory acidosis (the "Oxygen-induced Hypercapnia" phenomenon) [2]. **Analysis of Incorrect Options:** * **A. Fluid intake:** While hydration helps thin secretions, "three glasses daily" (approx. 750ml) is insufficient. COPD patients typically require 2–3 liters/day to maintain systemic hydration and facilitate mucociliary clearance. * **B. Semi-Fowler’s position:** While helpful, **High-Fowler’s** (90°) or the **Tripod position** is superior for advanced COPD. These positions maximize diaphragmatic excursion and reduce the work of breathing compared to semi-Fowler’s (30-45°). * **D. Administering a sedative:** This is **背indicated**. Sedatives (like benzodiazepines or opioids) depress the central respiratory drive, which can lead to fatal respiratory failure in a patient already struggling with gas exchange [2]. **High-Yield Clinical Pearls for NEET-PG:** * **Target SpO2 in COPD:** Aim for **88–92%** [3]. Over-oxygenation risks abolishing the hypoxic drive and increasing V/Q mismatch (Haldane effect) [2]. * **Venturi Mask Principle:** It works on the **Bernoulli principle**, using high-velocity gas flow to entrain a specific amount of room air. * **Gold Standard for Diagnosis:** Spirometry showing a post-bronchodilator **FEV1/FVC < 0.70**. * **Acute Exacerbation Management:** Oxygen (Venturi), Bronchodilators (SABA+SAMA), Systemic Corticosteroids, and Antibiotics (if evidence of infection) [4].

Question 70: What is the most important screening test for pulmonary thromboembolism?

A. D-dimer (Correct Answer)
B. X-ray
C. ECG
D. Angiography

Explanation: The diagnosis of Pulmonary Thromboembolism (PTE) relies on a combination of clinical probability and diagnostic testing. **D-dimer** is the most important screening test because of its exceptionally **high negative predictive value (NPV >95%)**. D-dimer is a fibrin degradation product that increases when a clot is formed and subsequently broken down. In patients with a low or intermediate clinical probability (Wells’ Score), a negative D-dimer effectively rules out PTE, making it the ideal initial screening tool. [1] **Analysis of Incorrect Options:** * **B. X-ray:** Chest X-rays are often normal in PTE [1]. While specific signs like *Hampton’s Hump* (wedge-shaped infarct) or *Westermark sign* (focal oligemia) exist, they are rare and lack the sensitivity required for screening. [1] * **C. ECG:** The most common ECG finding is sinus tachycardia [1]. The classic *S1Q3T3* pattern is specific but occurs in less than 20% of cases [1], making it unreliable for screening. * **D. Angiography:** CT Pulmonary Angiography (CTPA) is the **Gold Standard** (investigation of choice) for diagnosis [2]. However, it is not a screening test due to its cost, radiation exposure, and invasiveness compared to a simple blood test. **High-Yield Clinical Pearls for NEET-PG:** * **Screening Test:** D-dimer (ELISA method is most sensitive). * **Investigation of Choice:** CT Pulmonary Angiography (CTPA) [2]. * **Gold Standard (Historical):** Conventional Invasive Pulmonary Angiography. * **Most Common Symptom:** Sudden onset dyspnea. * **Most Common Sign:** Tachypnea. * **Wells’ Criteria:** Used to determine clinical probability before ordering a D-dimer or CTPA.

Practice by Chapter

Obstructive Airway Diseases (Asthma, COPD)

Practice Questions

Interstitial Lung Diseases

Practice Questions

Pulmonary Infections

Practice Questions

Pulmonary Vascular Diseases

Practice Questions

Pleural Diseases

Practice Questions

Sleep-Disordered Breathing

Practice Questions

Respiratory Failure

Practice Questions

Mediastinal Disorders

Practice Questions

Occupational Lung Diseases

Practice Questions

Pulmonary Function Testing

Practice Questions

Bronchiectasis and Cystic Fibrosis

Practice Questions

Lung Cancer Approach

Practice Questions

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