Pulmonology — MCQs

A 56-year-old diabetic man who consumes approximately 120g of alcohol per day presents with fatigue, cough with putrid-smelling sputum, and fever. He also has anemia, weight loss, pyorrhea, and gingivitis. His chest X-ray findings led to a diagnosis. What is the true statement regarding the treatment of this condition?

Q677Medium

A 64-year-old man, a chronic alcoholic, presents with fever, chills, and increasing shortness of breath. The patient appears in acute respiratory distress and complains of pleuritic chest pain. Physical examination shows crackles and decreased breath sounds over both lung fields. The patient exhibits tachypnea with flaring of the nares. The sputum is thick, mucoid, and blood-tinged. Which of the following pathogens is the most common cause of this patient's pulmonary infection?

Q678Easy

What is the investigation of choice (IOC) for diagnosing bronchiectasis?

Q679Easy

What is the most common precipitating factor for COPD?

Q680Medium

A 40-year-old alcoholic develops cough and fever. Chest X-ray shows an air-fluid level in the superior segment of the right lower lobe. What is the most likely etiologic agent?

Pulmonology Indian Medical PG Practice Questions and MCQs

Question 671: Which of the following is NOT an indication for assisted ventilation in acute severe asthma?

A. PEFR 50-60% of predicted value (Correct Answer)
B. Rising PaCO2 > 6 kPa (45 mm Hg)
C. Diminishing level of consciousness
D. Falling PaO2 < 8 kPa (60 mm Hg)

Explanation: In acute severe asthma, the decision to initiate assisted ventilation (mechanical or non-invasive) is based on signs of **impending respiratory failure** and exhaustion [1]. ### **Why Option A is the Correct Answer** A **Peak Expiratory Flow Rate (PEFR) of 50-60%** of the predicted value indicates a **moderate to severe exacerbation**, but it is not an indication for assisted ventilation. In most guidelines (like GINA or BTS), "Life-threatening" asthma is defined by a PEFR **<33%** of predicted [1]. Patients with 50-60% PEFR are typically managed with intensive pharmacological therapy (nebulized bronchodilators and systemic corticosteroids) and close monitoring, as they still maintain reasonable ventilatory effort [1]. ### **Analysis of Incorrect Options (Indications for Ventilation)** * **Option B (Rising PaCO2 > 45 mmHg):** In early asthma attacks, patients hyperventilate, leading to a *low* PaCO2. A "normal" or rising PaCO2 indicates that the patient is fatiguing and can no longer maintain the work of breathing [1]. This is a critical warning sign of respiratory failure. * **Option C (Diminishing level of consciousness):** Confusion, coma, or exhaustion are absolute clinical indications for intubation, as they suggest cerebral hypoxia and the inability to protect the airway [1]. * **Option D (Falling PaO2 < 60 mmHg):** Refractory hypoxemia despite high-flow supplemental oxygen indicates severe V/Q mismatch and shunting, necessitating ventilatory support [1]. ### **High-Yield Clinical Pearls for NEET-PG** * **The "Silent Chest":** A clinical sign of life-threatening asthma where airflow is so low that wheezing disappears; this is an emergency. * **Pulsus Paradoxus:** A drop in systolic BP >10 mmHg during inspiration is common in severe asthma. * **ABG Hallmark:** The most ominous finding in an acute attack is a **rising PaCO2** (Respiratory Acidosis) [1]. * **Indications for Intubation:** Exhaustion, silent chest, cyanosis, bradycardia, or pH < 7.35 [1].

Question 672: All of the following are used in the treatment of pulmonary hypertension except?

A. Endothelin receptor antagonist
B. Phosphodiesterase inhibitors
C. Calcium channel blockers
D. Beta blockers (Correct Answer)

Explanation: **Explanation:** The primary goal in treating Pulmonary Arterial Hypertension (PAH) is to reduce pulmonary vascular resistance and improve right ventricular function. **Why Beta Blockers are the correct answer (The "Except"):** Beta-blockers are generally **contraindicated** in PAH. The right ventricle (RV) in PAH patients is highly dependent on sympathetic drive to maintain stroke volume and heart rate in the face of high afterload. Beta-blockers can decrease RV contractility and lead to bradycardia, potentially precipitating acute right heart failure and hemodynamic collapse. **Why the other options are used:** * **Endothelin Receptor Antagonists (e.g., Bosentan, Ambrisentan):** These block endothelin-1, a potent vasoconstrictor and smooth muscle mitogen, thereby promoting vasodilation and preventing vascular remodeling. * **Phosphodiesterase-5 (PDE-5) Inhibitors (e.g., Sildenafil, Tadalafil):** These increase intracellular cGMP levels, leading to nitric oxide-mediated vasodilation of the pulmonary vasculature. * **Calcium Channel Blockers (e.g., Nifedipine, Diltiazem):** These are used **only** in a small subset of patients (approx. 10%) who demonstrate a positive "Vasoreactivity Test" during right heart catheterization. **High-Yield Clinical Pearls for NEET-PG:** 1. **Gold Standard Diagnosis:** Right Heart Catheterization (RHC) is required to confirm PAH (Mean Pulmonary Artery Pressure >20 mmHg at rest). 2. **Prostacyclins:** Epoprostenol (IV) is the drug of choice for severe (WHO Class IV) PAH. 3. **Soluble Guanylate Cyclase Stimulator:** Riociguat is a newer agent used in both PAH and Chronic Thromboembolic Pulmonary Hypertension (CTEPH). 4. **Avoidance:** Along with beta-blockers, ACE inhibitors and Diuretics (in high doses) should be used with extreme caution to avoid reducing RV preload.

Question 673: What indicates reversible airway obstruction?

A. FEV1 decrease by 50% after SABA administration
B. FEV1 increase by 12% after SABA administration (Correct Answer)
C. FEV1 decrease by 25% after SABA administration
D. FEV1 decrease by 5% after SABA administration

Explanation: **Explanation:** The assessment of **reversibility** is a cornerstone in the diagnosis of Asthma and in differentiating it from COPD. Reversibility is defined as a significant improvement in lung function following the administration of a Short-Acting Beta-2 Agonist (SABA), such as Salbutamol [1]. **Why Option B is Correct:** According to the GINA (Global Initiative for Asthma) and ATS/ERS guidelines, **bronchodilator reversibility** is objectively defined as: 1. An increase in **FEV1 of ≥12%** from the baseline, **AND** 2. An absolute increase in **FEV1 of ≥200 mL**. Option B correctly identifies the percentage threshold required to diagnose reversible airway obstruction, which is characteristic of bronchial asthma [1]. **Why Other Options are Incorrect:** * **Options A, C, and D:** These options suggest a **decrease** in FEV1 after SABA administration. A decrease in FEV1 following a bronchodilator is clinically atypical. A decrease in FEV1 is usually sought during a **Bronchial Provocation Test** (e.g., Methacholine challenge), where a $\geq$20% drop (PC20) indicates airway hyperresponsiveness [2]. **High-Yield Clinical Pearls for NEET-PG:** * **Gold Standard:** Spirometry is the investigation of choice for diagnosing obstructive lung diseases [1]. * **COPD vs. Asthma:** In COPD, airflow obstruction is typically **irreversible** or only partially reversible (FEV1/FVC ratio remains <0.70 post-bronchodilator) [1]. * **Diurnal Variation:** Another indicator of asthma is a Peak Expiratory Flow (PEF) variability of >10% [1]. * **Wait Time:** Reversibility is typically measured 15–20 minutes after administering 200–400 mcg of Salbutamol [1].

Question 674: A 60-year-old male with a long-standing history of breathlessness and heavy smoking since age 20 presents with an anxious, emaciated appearance, puffing for breath but not cyanosed. The chest is barrel-shaped. What is an expected additional clinical finding?

A. Elevated domes of the diaphragm
B. Left ventricular hypertrophy
C. Muffled heart sounds (Correct Answer)
D. Gynecomastia

Explanation: ### **Explanation** The clinical presentation describes a classic **"Pink Puffer"** (Type A COPD), typically associated with **Emphysema** [1]. The patient is emaciated (due to increased work of breathing), non-cyanotic (maintaining oxygenation through hyperventilation), and has a barrel-shaped chest [1]. **Why "Muffled Heart Sounds" is correct:** In emphysema, there is permanent enlargement of airspaces distal to the terminal bronchioles and destruction of alveolar walls. This leads to **pulmonary hyperinflation**. The lungs over-expand and interpose between the heart and the chest wall. Since air is a poor conductor of sound, this increased retrosternal airspace acts as an acoustic insulator, leading to **muffled or distant heart sounds** on auscultation [1]. Breath sounds are also typically quiet [1]. **Analysis of Incorrect Options:** * **A. Elevated domes of the diaphragm:** In emphysema, hyperinflation causes **flattening** of the diaphragmatic domes (best seen on a lateral X-ray), not elevation. * **B. Left ventricular hypertrophy (LVH):** COPD primarily affects the right side of the heart. Chronic hypoxia leads to pulmonary hypertension, which may cause **Right Ventricular Hypertrophy (Cor Pulmonale)**. * **C. Gynecomastia:** This is not a feature of COPD. **High-Yield Clinical Pearls for NEET-PG:** * **Pink Puffers (Emphysema):** High V/Q mismatch, dyspnea-dominant, cachectic, barrel chest (increased AP diameter) [1]. * **Blue Bloaters (Chronic Bronchitis):** Low V/Q mismatch, cough-dominant, cyanotic, edematous (due to early right heart failure) [1]. * **Radiological signs of Emphysema:** Hyperlucent lung fields, flattened diaphragms, increased retrosternal airspace (>2.5 cm), and a "saber-sheath" trachea. * **Percussion Note:** Hyper-resonant due to trapped air.

Question 675: Which of the following scoring systems is used to assess chest involvement in Sarcoidosis?

A. Brasfield scoring system
B. Wisconsin scoring system
C. Shwachman-Kulczycki scoring system
D. Scadding scoring system (Correct Answer)

Explanation: ### Explanation **Correct Option: D (Scadding scoring system)** The **Scadding system** is the classic staging method used to categorize the severity of pulmonary involvement in Sarcoidosis based on Chest X-ray (CXR) findings. It is crucial for prognosis, as higher stages correlate with a lower likelihood of spontaneous remission. * **Stage 0:** Normal CXR. * **Stage 1:** Bilateral Hilar Lymphadenopathy (BHL) only. * **Stage 2:** BHL + Parenchymal infiltrates. * **Stage 3:** Parenchymal infiltrates only (no BHL). * **Stage 4:** Pulmonary fibrosis (honeycombing, volume loss). **Analysis of Incorrect Options:** * **A. Brasfield scoring system:** Used to evaluate the severity of lung disease specifically in **Cystic Fibrosis** based on five radiographic categories. * **B. Wisconsin scoring system:** Another radiographic scoring system used for **Cystic Fibrosis**, often used in newborn screening research. * **C. Shwachman-Kulczycki scoring system:** The oldest and most widely used clinical (not just radiographic) scoring system to assess the overall severity of **Cystic Fibrosis** (evaluates nutrition, physical activity, physical exam, and CXR). **High-Yield Clinical Pearls for NEET-PG:** * **Sarcoidosis Hallmark:** Non-caseating granulomas on histology. * **Lofgren Syndrome:** A triad of BHL, Erythema Nodosum, and Migratory Polyarthralgia (indicates a good prognosis) [1]. * **Heerfordt Syndrome (Uveoparotid fever):** Parotid enlargement, Facial nerve palsy, and Anterior uveitis. * **Biomarker:** Elevated **Serum ACE levels** (reflects total granuloma burden) and hypercalciuria/hypercalcemia [1].

Question 676: A 56-year-old diabetic man who consumes approximately 120g of alcohol per day presents with fatigue, cough with putrid-smelling sputum, and fever. He also has anemia, weight loss, pyorrhea, and gingivitis. His chest X-ray findings led to a diagnosis. What is the true statement regarding the treatment of this condition?

A. Patients with fever persisting for 5 days should undergo bronchoscopy.
B. Metronidazole is preferred over clindamycin if used alone.
C. Duration of treatment is 7 days.
D. Clindamycin is the initial treatment of choice in this setting. (Correct Answer)

Explanation: ### **Explanation** **Diagnosis: Lung Abscess (Anaerobic)** The clinical presentation of high alcohol intake (predisposing to aspiration), poor oral hygiene (pyorrhea/gingivitis), and "putrid-smelling" sputum is classic for a **lung abscess** caused by anaerobic bacteria. **1. Why Option D is Correct:** **Clindamycin** is historically the drug of choice for anaerobic lung infections and lung abscesses. It has superior efficacy compared to penicillin or metronidazole alone because it covers both anaerobic organisms and microaerophilic streptococci. While Beta-lactam/Beta-lactamase inhibitor combinations (e.g., Piperacillin-Tazobactam or Amoxicillin-Clavulanate) are now also used as first-line therapy, Clindamycin remains a standard "textbook" answer for NEET-PG. **2. Why Other Options are Incorrect:** * **Option A:** Fever in lung abscess patients typically takes time to resolve. It is common for patients to remain febrile for **7–10 days** after starting antibiotics. Bronchoscopy is only indicated if there is a suspicion of an underlying malignancy or if the patient fails to respond to therapy after 10–14 days. [1] * **Option B:** Metronidazole is **not** preferred as monotherapy. While it has excellent anaerobic coverage, it is ineffective against microaerophilic streptococci often present in these polymicrobial infections. It must be combined with Penicillin if used. * **Option C:** Lung abscesses require prolonged treatment. The duration is typically **3 to 6 weeks** (or until the chest X-ray shows the cavity has resolved or reached a small, stable scar). **3. Clinical Pearls for NEET-PG:** * **Most common site:** Posterior segment of the right upper lobe (due to gravity and bronchial anatomy during aspiration). * **Hallmark sign:** Air-fluid level on Chest X-ray. * **Putrid Sputum:** Pathognomonic for anaerobic infection. * **Primary vs. Secondary:** Primary occurs in healthy individuals (aspiration); Secondary occurs due to bronchial obstruction (cancer) or systemic immunosuppression.

Question 677: A 64-year-old man, a chronic alcoholic, presents with fever, chills, and increasing shortness of breath. The patient appears in acute respiratory distress and complains of pleuritic chest pain. Physical examination shows crackles and decreased breath sounds over both lung fields. The patient exhibits tachypnea with flaring of the nares. The sputum is thick, mucoid, and blood-tinged. Which of the following pathogens is the most common cause of this patient's pulmonary infection?

A. Legionella pneumophila
B. Klebsiella pneumoniae (Correct Answer)
C. Mycoplasma pneumoniae
D. Streptococcus pneumoniae

Explanation: ### Explanation **Correct Answer: B. Klebsiella pneumoniae** The clinical presentation is classic for **Friedländer’s pneumonia**, caused by *Klebsiella pneumoniae*. The key diagnostic clues in this vignette are: 1. **Risk Factor:** Chronic alcoholism (which impairs host defenses and increases the risk of oropharyngeal aspiration) [1]. 2. **Sputum Characteristics:** "Thick, mucoid, and blood-tinged" sputum is the classic description of **"Currant Jelly" sputum**, caused by the organism's thick polysaccharide capsule and tissue necrosis. While *S. pneumoniae* typically causes 'rusty' sputum, necrotizing infections like *Klebsiella* can present with frank haemoptysis or thick mucoid blood [3]. 3. **Severity:** *Klebsiella* typically causes a severe, necrotizing lobar pneumonia, often involving the upper lobes, which can lead to bulging of the interlobar fissures on X-ray. Poor dental hygiene is another specific risk factor to consider for *Klebsiella* [2]. --- ### Why the other options are incorrect: * **A. Legionella pneumophila:** Typically associated with contaminated water sources (AC ducts, cooling towers) [1]. It often presents with extra-pulmonary symptoms like diarrhea, hyponatremia, and confusion. * **C. Mycoplasma pneumoniae:** The most common cause of "Atypical Pneumonia." It usually affects younger patients and presents with a non-productive cough, low-grade fever, and "walking pneumonia" symptoms rather than acute respiratory distress. * **D. Streptococcus pneumoniae:** While it is the **most common cause of community-acquired pneumonia (CAP) overall** [1], the specific mention of chronic alcoholism and the characteristic "currant jelly" sputum strongly points toward *Klebsiella* in a board-exam context. --- ### High-Yield Clinical Pearls for NEET-PG: * **Klebsiella Pneumonia:** Gram-negative, encapsulated, non-motile bacilli. * **Radiology:** Look for the **"Bulging Fissure Sign"** due to heavy inflammatory exudate. * **Common Complications:** Lung abscess formation and empyema are frequent due to the necrotizing nature of the infection. * **Other Risk Groups:** Diabetics and patients with chronic lung disease (COPD).

Question 678: What is the investigation of choice (IOC) for diagnosing bronchiectasis?

A. High-resolution computed tomography (HRCT) scan (Correct Answer)
B. Spiral CT scan
C. Bronchoscopy
D. Pulmonary angiography

Explanation: **Explanation:** **1. Why HRCT is the Investigation of Choice (IOC):** High-resolution computed tomography (HRCT) is the gold standard for diagnosing bronchiectasis due to its high sensitivity (>95%) and specificity. It allows for the visualization of thin (1–2 mm) sections of lung parenchyma, enabling the identification of permanent bronchial dilation. Key diagnostic signs on HRCT include: * **Signet Ring Sign:** The internal diameter of the bronchus is larger than its accompanying pulmonary artery. * **Tram-track Sign:** Non-tapering, parallel bronchial walls. * **Lack of tapering:** Bronchi visible within 1 cm of the costal pleura. **2. Why other options are incorrect:** * **Spiral CT scan:** While useful for pulmonary embolism (CTPA), it lacks the fine spatial resolution of HRCT required to detect subtle airway wall thickening and early bronchiectatic changes. * **Bronchoscopy:** This is an invasive procedure used to identify the *cause* of localized bronchiectasis (e.g., foreign body, endobronchial tumor) or to obtain cultures, but it cannot visualize the structural dilation of distal airways. * **Pulmonary angiography:** This is the gold standard for diagnosing pulmonary vascular malformations or as a precursor to bronchial artery embolization in cases of massive hemoptysis, but it has no role in diagnosing airway dilation. **3. Clinical Pearls for NEET-PG:** * **Chest X-ray:** Usually the initial investigation; may show "tram-track" shadows, but can be normal in early disease [1]. * **Bronchography:** Historically the gold standard, but now obsolete due to the non-invasive nature of HRCT. * **Etiology Tip:** If bronchiectasis is seen in the **upper lobes**, suspect Cystic Fibrosis; if in the **lower lobes**, suspect post-infectious causes or idiopathic disease. * **Kartagener Syndrome:** A high-yield triad of Bronchiectasis, Sinusitis, and Situs Inversus [2].

Question 679: What is the most common precipitating factor for COPD?

A. Environment
B. Smoking (Correct Answer)
C. Allergen
D. All of the above

Explanation: **Explanation:** **1. Why Smoking is the Correct Answer:** Cigarette smoking is the single most important and common risk factor (precipitating factor) for the development of Chronic Obstructive Pulmonary Disease (COPD), accounting for approximately 80–90% of cases [1]. The underlying pathophysiology involves the inhalation of toxic particles and gases which trigger a chronic inflammatory response in the airways and lung parenchyma [1]. This leads to the activation of macrophages and neutrophils, release of proteases (like elastase), and oxidative stress, resulting in the characteristic airway narrowing (chronic bronchitis) and alveolar destruction (emphysema) [1]. **2. Why Other Options are Incorrect:** * **A. Environment:** While environmental factors such as biomass fuel smoke (common in rural India), air pollution, and occupational dust (silica, cotton) are significant risk factors, they are statistically less common than tobacco smoking on a global and clinical scale [1]. * **C. Allergen:** Allergens are the primary triggers for **Bronchial Asthma**, not COPD [2]. While "Asthma-COPD Overlap Syndrome" (ACOS) exists, the fundamental pathology of COPD is driven by irritants and toxins rather than IgE-mediated hypersensitivity to allergens [2]. * **D. All of the above:** Since smoking is the predominant and primary cause, this option is incorrect in the context of identifying the "most common" factor. **3. High-Yield Clinical Pearls for NEET-PG:** * **Genetic Factor:** The most common genetic cause of COPD is **Alpha-1 Antitrypsin Deficiency** (consider this in young, non-smokers with panacinar emphysema). * **Index for Smoking:** The risk of COPD is directly proportional to "Pack Years" (Packs per day × Years smoked) [1]. * **Gold Standard Diagnosis:** Spirometry showing a post-bronchodilator **FEV1/FVC ratio < 0.70**. * **Mortality Benefit:** Smoking cessation and Long-term Oxygen Therapy (LTOT) are the only interventions proven to improve survival in COPD patients.

Question 680: A 40-year-old alcoholic develops cough and fever. Chest X-ray shows an air-fluid level in the superior segment of the right lower lobe. What is the most likely etiologic agent?

A. Streptococcus pneumoniae
B. Haemophilus influenzae
C. Legionella
D. Anaerobes (Correct Answer)

Explanation: The clinical presentation of a **lung abscess** (characterized by an air-fluid level on chest X-ray) in an **alcoholic patient** strongly points toward **anaerobic infection** resulting from aspiration. **1. Why Anaerobes are correct:** Alcoholics have an altered state of consciousness, which predisposes them to the aspiration of oropharyngeal secretions. These secretions are heavily colonized with anaerobes (e.g., *Peptostreptococcus*, *Fusobacterium*, and *Bacteroides*). The **superior segment of the right lower lobe** is the most common site for aspiration pneumonia when a patient is in a supine position, due to the vertical orientation of the right main bronchus. Anaerobic infections typically lead to tissue necrosis and liquefaction, resulting in the classic "air-fluid level" seen on imaging. **2. Why other options are incorrect:** * **Streptococcus pneumoniae:** The most common cause of community-acquired pneumonia; however, it typically presents as lobar consolidation and rarely causes cavitation or abscess formation (except for Type 3) [1]. * **Haemophilus influenzae:** Commonly affects patients with COPD but is not a typical cause of cavitary lung lesions or abscesses. * **Legionella:** Causes "atypical" pneumonia often associated with hyponatremia and GI symptoms. While it can be severe, it does not typically present with a localized air-fluid level in an aspiration distribution. **Clinical Pearls for NEET-PG:** * **Most common site for aspiration:** Superior segment of the lower lobes or posterior segment of the upper lobes. * **Putrid sputum:** A classic clinical sign pathognomonic for anaerobic lung infection. * **Treatment of choice:** Clindamycin or Beta-lactam/Beta-lactamase inhibitors (e.g., Piperacillin-Tazobactam) [2]. * **Differential for cavitary lesions:** Remember the mnemonic **"CAVITY"**: **C**ancer, **A**utoimmune (Wegener’s), **V**ascular (Septic emboli), **I**nfection (TB, Anaerobes, Fungi), **T**rauma, **Y**outh (CPAM).

Practice by Chapter

Obstructive Airway Diseases (Asthma, COPD)

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Interstitial Lung Diseases

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Pulmonary Infections

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Pulmonary Vascular Diseases

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Pleural Diseases

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Sleep-Disordered Breathing

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Respiratory Failure

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Mediastinal Disorders

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Occupational Lung Diseases

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Pulmonary Function Testing

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Bronchiectasis and Cystic Fibrosis

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Lung Cancer Approach

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