Pulmonology — MCQs

A 28-year-old man presents with coughing up blood and sputum. He has a history of recurrent pneumonias and a chronic cough productive of foul-smelling purulent sputum. He has no other past medical history and is a lifetime nonsmoker. On physical examination, there are no oral lesions, heart sounds are normal, and wet inspiratory crackles are heard at the lung bases posteriorly. He also has clubbing of his fingers, but there is no hepatosplenomegaly or any palpable lymph nodes. Chest X-ray shows fibrosis and pulmonary infiltrates in the right lower lung. Which of the following is the most appropriate initial diagnostic test?

Q60Easy

Pulmonary tuberculosis is more common in patients with which of the following associated diseases?

Pulmonology Indian Medical PG Practice Questions and MCQs

Question 51: What is the most diagnostic test for pulmonary embolism in a high-risk case?

A. Multidetector CT angiography (Correct Answer)
B. Catheter angiography
C. D-dimer
D. Ventilation perfusion scan

Explanation: The diagnosis of Pulmonary Embolism (PE) depends on the patient's clinical probability. In high-risk cases, the goal is rapid, definitive visualization of the pulmonary vasculature. **1. Why Multidetector CT Angiography (MDCTA) is correct:** MDCTA is currently the **first-line diagnostic investigation** and the "gold standard" in clinical practice for PE [1]. It offers high sensitivity and specificity (PIOPED II study) and has the advantage of being non-invasive, widely available, and capable of identifying alternative diagnoses (e.g., pneumonia, aortic dissection) [2]. Modern multidetector scanners can visualize even subsegmental emboli with high precision. **2. Why the other options are incorrect:** * **Catheter Angiography:** Historically the "reference standard," it is now rarely performed because it is invasive, carries a higher risk of complications, and MDCTA provides comparable diagnostic accuracy. * **D-dimer:** This test has a high negative predictive value but very low specificity. It is used to **rule out** PE in low-to-moderate risk patients. In a high-risk case, a D-dimer is unnecessary as a negative result would not override clinical suspicion. * **Ventilation-Perfusion (V/Q) Scan:** This is a second-line test, primarily reserved for patients with contraindications to CT contrast (e.g., renal failure or severe allergy) [1]. It often yields "indeterminate" results, requiring further testing. **Clinical Pearls for NEET-PG:** * **Initial Investigation of choice:** MDCTA. * **Best Initial Test (Screening):** Chest X-ray (to rule out other causes), though often normal or showing non-specific signs like *Westermark sign* [2] or *Hampton’s hump*. * **Investigation of choice in Pregnancy:** V/Q scan is often preferred to limit maternal breast radiation, though CTPA is also used. * **Gold Standard (Historical):** Invasive Pulmonary Angiography.

Question 52: Amylase increased in pleural fluid is seen in all of the following conditions except:

A. Rheumatoid arthritis (Correct Answer)
B. Esophageal perforation
C. Malignancy
D. Gallstone pancreatitis

Explanation: Pleural fluid amylase is considered elevated when it exceeds the upper limit of normal for serum amylase or when the pleural fluid-to-serum amylase ratio is >1.0. **Why Rheumatoid Arthritis (RA) is the correct answer:** In RA-associated pleural effusion, the characteristic biochemical markers are **very low glucose levels** (often <30 mg/dL), high LDH, and low pH [1]. Amylase levels are typically **normal**. Therefore, it is the "except" in this list. **Analysis of Incorrect Options:** * **Esophageal Perforation:** This causes the highest levels of pleural fluid amylase [1]. The amylase is **salivary** in origin, leaking through the mediastinum into the pleural space. * **Gallstone Pancreatitis:** Acute or chronic pancreatitis leads to elevated **pancreatic** amylase in the pleural fluid (usually left-sided) due to transdiaphragmatic lymphatic spread or fistula formation [2]. * **Malignancy:** Approximately 10% of malignant effusions (most commonly Adenocarcinoma of the lung or ovary) show elevated amylase [1]. In these cases, the amylase is usually the salivary isoenzyme produced by the tumor cells themselves. **High-Yield NEET-PG Pearls:** 1. **Differential for High Pleural Amylase:** Remember the mnemonic **"PEAM"** — **P**ancreatitis, **E**sophageal rupture, **A**denocarcinoma (Malignancy), and **M**esothelioma. 2. **RA Effusion Triad:** Low Glucose + High LDH + Low pH (and presence of RA cells/Ragocytes) [1]. 3. **Esophageal Rupture:** Look for low pH (often <6.0) and presence of squamous epithelial cells or food particles in the fluid [1]. 4. **Pancreatic Effusion:** The pleural fluid amylase level is often significantly higher than the concomitant serum amylase level [2].

Question 53: FEV1/FEVC ratio is decreased in all of the following conditions except?

A. Bronchiectasis
B. Emphysema
C. Chronic bronchitis
D. Tuberculosis (Correct Answer)

Explanation: The core concept tested here is the differentiation between **Obstructive** and **Restrictive** lung diseases using spirometry. ### **Explanation** The **FEV1/FVC ratio** is the primary tool to distinguish lung pathologies [1]. * In **Obstructive diseases**, air cannot be exhaled quickly due to airway narrowing or loss of elastic recoil. FEV1 decreases significantly more than FVC, leading to a **decreased ratio (<70%)** [1]. * In **Restrictive diseases**, lung volumes are reduced, but the airways remain patent. Both FEV1 and FVC decrease proportionately, or FVC decreases more, resulting in a **normal or increased ratio**. **Tuberculosis (Correct Answer):** TB typically causes parenchymal destruction and subsequent **fibrosis**. Pulmonary fibrosis is a classic **Restrictive Lung Disease**. Therefore, the FEV1/FVC ratio remains normal or is increased, not decreased. ### **Analysis of Incorrect Options** * **Bronchiectasis (A):** Characterized by permanent dilation of bronchi and mucus plugging, leading to airflow obstruction [3]. * **Emphysema (B):** A component of COPD where alveolar destruction leads to loss of elastic recoil and dynamic airway collapse during expiration [2]. * **Chronic Bronchitis (C):** Another component of COPD involving inflammation and mucus hypersecretion, causing significant airway obstruction. ### **High-Yield Clinical Pearls for NEET-PG** 1. **Mnemonic for Obstructive Diseases:** **CBABE** (Cystic Fibrosis, Bronchitis, Asthma, Bronchiectasis, Emphysema). All these show a **decreased** FEV1/FVC ratio. 2. **Restrictive Pattern:** Seen in Interstitial Lung Disease (ILD), Sarcoidosis, Scoliosis, and Fibrosis (post-TB). Look for **decreased Total Lung Capacity (TLC)**. 3. **Flow-Volume Loops:** * *Obstructive:* "Scooped-out" appearance. * *Restrictive:* "Witch’s Hat" appearance (tall, narrow, shifted to the right).

Question 54: What is the most common cause of acute cor pulmonale?

A. Pneumonia
B. Pulmonary thromboembolism (Correct Answer)
C. Chronic obstructive pulmonary disease
D. Primary spontaneous pneumothorax

Explanation: **Explanation:** **Cor pulmonale** is defined as right ventricular (RV) hypertrophy or dilation resulting from pulmonary hypertension caused by diseases of the lung parenchyma or pulmonary vasculature [1]. **Why Pulmonary Thromboembolism is correct:** Acute cor pulmonale occurs when there is a sudden, massive increase in pulmonary vascular resistance, leading to acute RV strain and failure. **Pulmonary Thromboembolism (PTE)** is the most common cause of this acute presentation [1]. A large embolus (such as a saddle embolus) mechanically obstructs the pulmonary arteries, causing a rapid rise in pulmonary artery pressure. Because the right ventricle is thin-walled and not adapted to handle sudden pressure loads, it dilates rapidly, leading to the classic clinical and ECG findings of acute right heart strain [1]. Thrombolysis is typically indicated in patients presenting with acute massive PE accompanied by cardiogenic shock [2]. **Analysis of Incorrect Options:** * **A. Pneumonia:** While severe pneumonia can cause hypoxia and localized vasoconstriction, it rarely causes acute right heart failure unless it leads to massive ARDS. * **C. Chronic Obstructive Pulmonary Disease (COPD):** This is the **most common cause of chronic cor pulmonale** globally. It leads to RV hypertrophy over years due to chronic hypoxia and remodeling, rather than an acute event [1]. * **D. Primary Spontaneous Pneumothorax:** While a tension pneumothorax can cause hemodynamic collapse, it does so primarily by decreasing venous return (preload) rather than primary pulmonary hypertension leading to cor pulmonale [1]. **High-Yield Clinical Pearls for NEET-PG:** * **Most common cause of Chronic Cor Pulmonale:** COPD. * **Most common cause of Acute Cor Pulmonale:** Pulmonary Thromboembolism [1]. * **Classic ECG finding in Acute Cor Pulmonale:** S1Q3T3 pattern (specific but not sensitive) and Right Bundle Branch Block (RBBB) [1]. * **Gold Standard Diagnosis for PTE:** CT Pulmonary Angiography (CTPA). * **Definition Note:** Right heart failure due to left-sided heart disease is **not** considered cor pulmonale.

Question 55: About respiratory failure, which of the following statements is false?

A. Type III failure involves post-operative atelectasis.
B. Type II failure does not have a fall in PaO2 (hypoxia). (Correct Answer)
C. Type I failure involves hypoxia (PaO2).
D. Pneumonia usually presents with type I respiratory failure.

Explanation: ### Explanation **Why Option B is the Correct (False) Statement:** Respiratory failure is defined by the inability of the respiratory system to maintain adequate gas exchange [1]. **Type II respiratory failure (Hypercapnic)** is characterized by a primary failure of ventilation leading to elevated $PaCO_2$ (>45 mmHg) [2]. However, according to the alveolar gas equation, as $PaCO_2$ rises, the partial pressure of alveolar oxygen ($PAO_2$) must fall. Therefore, **Type II failure always involves hypoxia ($PaO_2$ < 60 mmHg)** unless the patient is breathing supplemental oxygen [2]. The statement that it does not have a fall in $PaO_2$ is physiologically incorrect. **Analysis of Other Options:** * **Option A (True):** Type III respiratory failure is specifically associated with **perioperative** conditions. It occurs due to decreased functional residual capacity (FRC) in the setting of abnormal abdominal wall mechanics, leading to basal atelectasis. * **Option C (True):** Type I respiratory failure is **Hypoxemic** failure [2]. It is defined by a $PaO_2$ < 60 mmHg with a normal or low $PaCO_2$. It is the most common form of respiratory failure [1]. * **Option D (True):** Pneumonia causes a V/Q mismatch and inflammatory exudate in the alveoli, which impairs oxygen diffusion [1]. This typically results in Type I failure [2]. **High-Yield Clinical Pearls for NEET-PG:** * **Type IV Respiratory Failure:** Refers to respiratory failure due to **shock** (hypoperfusion), where respiratory muscles consume a disproportionate amount of cardiac output. * **A-a Gradient:** Useful for differentiating causes of Type I failure. It is **increased** in pneumonia/PE but **normal** in hypoventilation (e.g., opioid overdose) or high altitude. * **Gold Standard Diagnosis:** Arterial Blood Gas (ABG) analysis is essential to classify respiratory failure [2].

Question 56: What is the best initial treatment for massive pulmonary embolism?

A. Intravenous tissue plasminogen activator (Correct Answer)
B. Heparin
C. Pulmonary thrombo-embolectomy
D. Low molecular weight heparin plus warfarin

Explanation: **Explanation:** The management of Pulmonary Embolism (PE) is determined by hemodynamic stability. **Massive PE** is defined by the presence of sustained hypotension (systolic BP <90 mmHg for >15 minutes) or shock. **1. Why Option A is correct:** In massive PE, the immediate goal is to dissolve the obstructing clot to relieve right ventricular (RV) strain and restore systemic circulation. **Intravenous tissue plasminogen activator (tPA)**, such as Alteplase, is the treatment of choice because it actively lyses the thrombus [2]. Thrombolysis has been shown to improve hemodynamics faster than heparin alone in unstable patients. **2. Why the other options are incorrect:** * **Option B & D:** Heparin (Unfractionated or LMWH) and Warfarin are **anticoagulants**. They prevent the propagation of an existing clot and the formation of new ones, but they do *not* actively dissolve the current life-threatening obstruction. These are the treatments of choice for **non-massive (stable) PE** [2]. * **Option C:** Pulmonary thrombo-embolectomy (surgical or catheter-based) is a definitive treatment but is generally reserved for patients with massive PE who have **absolute contraindications to thrombolysis** or those who have failed systemic thrombolysis [2]. **Clinical Pearls for NEET-PG:** * **Gold Standard Diagnosis:** CT Pulmonary Angiography (CTPA) [1]. * **Most Common ECG Finding:** Sinus tachycardia (S1Q3T3 is specific but not sensitive). * **Sub-massive PE:** Defined by RV dysfunction or elevated Troponin/BNP but with **normal BP**. Treatment is usually anticoagulation, though "rescue thrombolysis" may be considered [2]. * **Absolute Contraindications to tPA:** Prior intracranial hemorrhage, known structural cerebrovascular lesion, ischemic stroke within 3 months, or active internal bleeding.

Question 57: Which of the following are features of pulmonary embolism?

A. Respiratory alkalosis, Right axis deviation, Ventricular strain
B. Right axis deviation, Normal A-a Gradient, Ventricular strain
C. Respiratory alkalosis, Right axis deviation, Ventricular strain (Correct Answer)
D. Respiratory alkalosis, Right axis deviation

Explanation: **Explanation:** Pulmonary Embolism (PE) triggers a sequence of physiological changes due to mechanical obstruction of the pulmonary vasculature and subsequent reflex mechanisms. 1. **Respiratory Alkalosis:** Obstruction leads to a ventilation-perfusion (V/Q) mismatch and stimulation of irritant receptors, causing **hyperventilation**. This results in the "blowing off" of $CO_2$ (hypocapnia), leading to an increase in blood pH (respiratory alkalosis) [1]. 2. **Right Axis Deviation (RAD) & Ventricular Strain:** The sudden increase in pulmonary vascular resistance causes acute **Right Ventricular (RV) pressure overload**. On an ECG, this manifests as Right Axis Deviation and signs of RV strain (such as T-wave inversions in leads V1-V4 and the classic S1Q3T3 pattern) [1]. **Analysis of Options:** * **Option B is incorrect** because PE typically causes an **increased A-a gradient** due to V/Q mismatch and shunting. A normal A-a gradient is highly unlikely in acute PE. * **Option D is incorrect** because it is incomplete; while it lists two features, it omits ventricular strain, which is a hallmark finding in significant PE [1]. **High-Yield Clinical Pearls for NEET-PG:** * **Most common ECG finding:** Sinus tachycardia (S1Q3T3 is specific but not sensitive) [1]. * **Most common symptom:** Sudden onset dyspnea. * **Gold Standard Investigation:** CT Pulmonary Angiography (CTPA). * **ABG Profile:** Hypoxemia, Hypocapnia, and Respiratory Alkalosis with an elevated A-a gradient [1]. * **Westermark sign & Hampton’s Hump:** Classic but rare chest X-ray findings [1].

Question 58: A truck driver presented with a history of fever for four weeks and a dry cough. He also reports a weight loss of approximately 10 kg. X-ray shows bilateral reticulonodular infiltrates. What is the most likely diagnosis?

A. Tuberculosis
B. Pneumocystis pneumonia (Correct Answer)
C. Pneumococcal pneumonia
D. Interstitial lung disease

Explanation: The clinical presentation points toward an opportunistic infection in an immunocompromised host [1]. The patient’s occupation (truck driver) is a classic social high-yield marker in exams for high-risk behavior and potential HIV/AIDS [2]. **1. Why Pneumocystis pneumonia (PCP) is correct:** PCP, caused by *Pneumocystis jirovecii*, typically presents subacutely with a triad of **fever, dry cough, and progressive dyspnea**. Significant weight loss suggests underlying HIV [2]. Radiologically, PCP characteristically presents with **bilateral, symmetrical perihilar reticulonodular infiltrates** or "ground-glass" opacities [1]. The dry nature of the cough is a hallmark, as the organism does not cause alveolar exudate like typical bacteria. **2. Why the other options are incorrect:** * **Tuberculosis:** While common in HIV and causing weight loss, TB usually presents with a productive cough, hemoptysis, and focal findings (like upper lobe cavities or miliary patterns) rather than diffuse, symmetrical reticulonodular infiltrates [1]. * **Pneumococcal pneumonia:** This is an acute bacterial infection presenting with high-grade fever, productive "rusty" sputum, and **lobar consolidation** on X-ray, rather than a four-week chronic course with reticular patterns [4]. * **Interstitial Lung Disease (ILD):** While ILD shows reticulonodular patterns, it is a chronic, non-infectious inflammatory/fibrotic process [3]. It would not typically present with a four-week history of fever and rapid 10 kg weight loss. **Clinical Pearls for NEET-PG:** * **Investigation of choice:** Induced sputum or Bronchoalveolar Lavage (BAL) with **Gomori Methenamine Silver (GMS)** stain showing "crushed ping-pong ball" cysts [1]. * **Blood marker:** Elevated **Serum LDH** is highly sensitive for PCP in HIV patients. * **Treatment:** High-dose **TMP-SMX** is the drug of choice [1]. Add steroids if $PaO_2 < 70$ mmHg or A-a gradient $> 35$ mmHg.

Question 59: A 28-year-old man presents with coughing up blood and sputum. He has a history of recurrent pneumonias and a chronic cough productive of foul-smelling purulent sputum. He has no other past medical history and is a lifetime nonsmoker. On physical examination, there are no oral lesions, heart sounds are normal, and wet inspiratory crackles are heard at the lung bases posteriorly. He also has clubbing of his fingers, but there is no hepatosplenomegaly or any palpable lymph nodes. Chest X-ray shows fibrosis and pulmonary infiltrates in the right lower lung. Which of the following is the most appropriate initial diagnostic test?

A. Chest CT scan (Correct Answer)
B. Bronchoscopy
C. Bronchography
D. Open thoracotomy

Explanation: ### Explanation **Diagnosis: Bronchiectasis** The clinical presentation of chronic cough with foul-smelling purulent sputum, recurrent pneumonias, hemoptysis, and digital clubbing [1] is classic for **Bronchiectasis**. The presence of wet inspiratory crackles [2] at the lung bases and X-ray findings of fibrosis/infiltrates further support this diagnosis. **1. Why Chest CT scan is the correct answer:** High-Resolution Computed Tomography (HRCT) is the **gold standard** and the most appropriate initial diagnostic test for bronchiectasis. It has replaced older methods due to its high sensitivity and specificity. Key HRCT findings include: * **Signet ring sign:** Bronchial artery appearing smaller than the dilated bronchus. * **Tram-track appearance:** Non-tapering, thickened bronchial walls. * Lack of bronchial tapering towards the periphery. **2. Why other options are incorrect:** * **Bronchoscopy (B):** While useful for identifying localized obstructions (like a foreign body or tumor) or obtaining cultures, it is not the primary diagnostic tool for the anatomical changes of bronchiectasis. * **Bronchography (C):** This was historically the gold standard (using contrast media in the airways), but it is now obsolete because it is invasive and has been entirely replaced by the non-invasive HRCT. * **Open thoracotomy (D):** This is a major surgical procedure used for lung resection or biopsy; it is never an initial diagnostic test for airway disease. **Clinical Pearls for NEET-PG:** * **Most common cause in India:** Post-tubercular bronchiectasis. * **Most common organism (Non-CF):** *Haemophilus influenzae*. * **Most common organism (Cystic Fibrosis):** *Pseudomonas aeruginosa*. * **Kartagener Syndrome:** A high-yield triad of bronchiectasis, situs inversus, and sinusitis (look for "displaced heart sounds" in questions) [3]. * **Treatment:** Focuses on airway clearance (chest physiotherapy), antibiotics for exacerbations, and bronchodilators.

Question 60: Pulmonary tuberculosis is more common in patients with which of the following associated diseases?

A. Acquired immune deficiency syndrome
B. Diabetes mellitus
C. Chronic renal failure
D. Mitral stenosis (Correct Answer)

Explanation: **Explanation:** The correct answer is **Mitral Stenosis**. This question focuses on the physiological environment required for the proliferation of *Mycobacterium tuberculosis*. **Why Mitral Stenosis is the Correct Answer:** *Mycobacterium tuberculosis* is a strict aerobe that thrives in areas with high oxygen tension ($PO_2$). In a healthy individual, the apices of the lungs have the highest ventilation-perfusion (V/Q) ratio, making them the most common site for secondary TB. In **Mitral Stenosis**, there is chronic pulmonary venous congestion and pulmonary hypertension. This leads to increased pulmonary capillary pressure, particularly in the lower lobes, which forces a redistribution of blood flow. This results in **decreased oxygen tension** in the lung tissues. This "congested" environment is physiologically **antagonistic** to the growth of the tubercle bacilli. Therefore, pulmonary TB is statistically **less common** in patients with Mitral Stenosis compared to the general population. **Analysis of Incorrect Options:** * **AIDS (Option A):** This is the strongest risk factor for the development of TB [1]. Immunosuppression (low CD4 count) leads to reactivation of latent TB and increased susceptibility to primary infection [1]. * **Diabetes Mellitus (Option B):** Hyperglycemia impairs neutrophil function and cell-mediated immunity, making diabetics 3 times more likely to develop TB. * **Chronic Renal Failure (Option C):** Uremia causes significant T-lymphocyte dysfunction, increasing the risk of both pulmonary and extrapulmonary TB. **High-Yield Clinical Pearls for NEET-PG:** * **The "Protective" Effect:** Mitral stenosis is traditionally considered "protective" against pulmonary TB due to chronic pulmonary congestion. * **Silicosis:** This is another high-yield association; it carries the highest relative risk among occupational lung diseases for TB (Silicotuberculosis) [2]. * **Gastrectomy:** Post-gastrectomy patients have an increased risk of TB due to malnutrition and vitamin D deficiency.

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

Want unlimited practice?

Get full access to all questions, explanations, and performance tracking.

Start For Free