Pulmonology — MCQs
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Reversible airway obstruction is defined as what percentage increase in FEV1, 15 minutes after an inhaled short-acting beta-2 agonist therapy?
A 62-year-old man with a 40-pack/year history of smoking presents with increased sputum production and marked shortness of breath. On examination, he is using accessory muscles of respiration, and breath sounds are diminished with expiratory wheezes. Your clinical diagnosis is chronic obstructive pulmonary disease (COPD) exacerbation. For the above patient, select the characteristic arterial pulse finding.
A 5-year-old female presents with dry cough and progressive breathlessness of two years duration. Examination reveals clubbing, cyanosis, and bibasilar crepitations. What is the probable diagnosis?
Which of the following is NOT a recognized cause of adult respiratory distress syndrome?
What is the gold standard for the diagnosis of pulmonary embolism?
Caplan's syndrome is characterized by pneumoconiosis with which of the following conditions?
True about pleural effusion?
A chronic smoker presents with cough and hemoptysis. The physician informs the patient that they have the most malignant type of bronchogenic carcinoma. Which type is it?
Which of the following is a contributory factor for developing cor-pulmonale in chronic bronchitis?
Which of the following is NOT associated with pulmonary arterial hypertension?
Pulmonology Indian Medical PG Practice Questions and MCQs
Question 591: Reversible airway obstruction is defined as what percentage increase in FEV1, 15 minutes after an inhaled short-acting beta-2 agonist therapy?
- A. > 5%
- B. > 10%
- C. > 15% (Correct Answer)
- D. > 20%
Explanation: The assessment of **Reversibility of Airway Obstruction** is a cornerstone in the diagnosis of Bronchial Asthma [1]. According to standard clinical guidelines (such as the British Thoracic Society), significant reversibility is defined as an **increase in FEV1 of >15%** (and usually >200 mL) from the baseline value, measured 15–20 minutes after inhaling a short-acting beta-2 agonist (SABA) like Salbutamol [1]. **Why Option C is Correct:** The threshold of >15% is used to distinguish asthma from other obstructive lung diseases like COPD. While COPD may show some improvement, a robust response (>15%) strongly suggests the hyper-responsive, reversible nature of the airways characteristic of asthma [1]. **Analysis of Incorrect Options:** * **A (>5%) & B (>10%):** These values are too low and lack specificity. Minor fluctuations in FEV1 can occur due to effort or technical variations and do not necessarily indicate a clinical response to bronchodilators. * **D (>20%):** While an improvement of >20% is definitely significant, it is not the minimum diagnostic threshold. Using 20% as the cutoff would result in many asthmatic patients being underdiagnosed. **High-Yield Clinical Pearls for NEET-PG:** * **GINA Guidelines Update:** While many textbooks still use >15%, the Global Initiative for Asthma (GINA) currently defines a positive bronchodilator reversibility test as an increase in FEV1 of **>12% AND >200 mL** from the baseline. However, in exams, if 12% is not an option, **15%** remains the classic "textbook" answer. * **Diurnal Variation:** A PEFR (Peak Expiratory Flow Rate) diurnal variation of **>10%** is also diagnostic of asthma. * **COPD vs. Asthma:** Reversibility is typically **absent or partial** in COPD, whereas it is **significant and characteristic** in Asthma [1].
Question 592: A 62-year-old man with a 40-pack/year history of smoking presents with increased sputum production and marked shortness of breath. On examination, he is using accessory muscles of respiration, and breath sounds are diminished with expiratory wheezes. Your clinical diagnosis is chronic obstructive pulmonary disease (COPD) exacerbation. For the above patient, select the characteristic arterial pulse finding.
- A. Pulsus tardus
- B. Pulsus paradoxus (Correct Answer)
- C. Hyperkinetic pulse
- D. Bisferiens pulse
Explanation: ### Explanation **Correct Answer: B. Pulsus paradoxus** **Why it is correct:** Pulsus paradoxus is defined as an exaggerated fall in systolic blood pressure (>10 mmHg) during inspiration. In severe **COPD or Asthma exacerbations**, the patient generates extreme negative intrathoracic pressure to overcome airway obstruction. This negative pressure increases venous return to the right ventricle (RV), causing the interventricular septum to bulge into the left ventricle (LV). This reduces LV filling and stroke volume. Additionally, the hyperinflated lungs and high negative pressure increase the "afterload" on the LV by making it harder to pump blood out of the thorax, further dropping the systolic pressure during inspiration [1]. **Why the other options are incorrect:** * **A. Pulsus tardus:** A slow-rising, low-amplitude pulse characteristic of **Aortic Stenosis**. * **C. Hyperkinetic pulse:** A bounding pulse seen in high-output states like **Anemia, Thyrotoxicosis, or Aortic Regurgitation**. * **D. Bisferiens pulse:** A pulse with two systolic peaks, typically seen in **HOCM** or combined **Aortic Stenosis and Regurgitation**. **Clinical Pearls for NEET-PG:** * **Classic Causes of Pulsus Paradoxus:** Cardiac Tamponade (most common association), Severe COPD/Asthma, Constrictive Pericarditis, and Restrictive Cardiomyopathy [1]. * **Reverse Pulsus Paradoxus:** Seen in patients on **positive pressure ventilation** and in **Hypertrophic Obstructive Cardiomyopathy (HOCM)**. * **Mechanism Tip:** In Tamponade, the mechanism is "ventricular interdependence" within a fixed pericardial space; in COPD, it is primarily due to extreme fluctuations in intrathoracic pressure.
Question 593: A 5-year-old female presents with dry cough and progressive breathlessness of two years duration. Examination reveals clubbing, cyanosis, and bibasilar crepitations. What is the probable diagnosis?
- A. Bronchiectasis
- B. Lung abscess
- C. Interstitial lung disease (Correct Answer)
- D. Pulmonary tuberculosis
Explanation: ### Explanation **Correct Answer: C. Interstitial Lung Disease (ILD)** The clinical triad of **progressive breathlessness, digital clubbing, and bibasilar end-expiratory crepitations (Velcro crackles)** is the hallmark of Interstitial Lung Disease [1]. In children, ILD (often termed chILD) presents with a chronic dry cough and restrictive lung physiology [1]. The presence of **cyanosis** indicates significant ventilation-perfusion mismatch and impaired gas exchange across the thickened alveolar-capillary membrane, reflecting the progressive nature of the fibrosis [1]. **Why other options are incorrect:** * **A. Bronchiectasis:** While it presents with clubbing and crepitations, the cough is typically **productive** with copious purulent sputum (not dry). Crepitations are usually coarse and may change with coughing. * **B. Lung Abscess:** This is an acute to subacute condition characterized by high-grade fever and the expectoration of foul-smelling sputum. While it can cause clubbing, it does not present with progressive breathlessness over two years or bilateral basal crepitations. * **C. Pulmonary Tuberculosis:** In children, TB usually presents with constitutional symptoms (fever, weight loss, night sweats). While it can cause chronic cough, bilateral basal crepitations and early clubbing are not its typical primary presentations. **High-Yield Clinical Pearls for NEET-PG:** * **Velcro Crackles:** Fine, high-pitched, end-expiratory crepitations are pathognomonic for ILD/Pulmonary Fibrosis [1]. * **Clubbing in Pulmonology:** Common causes include Suppurative lung diseases (Bronchiectasis, Abscess, Empyema), Bronchogenic Carcinoma, and ILD [1]. **Note:** Simple Chronic Bronchitis and Asthma do *not* typically cause clubbing. * **Diagnosis:** The gold standard for diagnosing the pattern of ILD is **HRCT (High-Resolution Computed Tomography)**, which shows reticular opacities or ground-glass appearance [1].
Question 594: Which of the following is NOT a recognized cause of adult respiratory distress syndrome?
- A. Smoke inhalation
- B. Malignant hypertension (Correct Answer)
- C. Gastric aspiration
- D. Viral pneumonia
Explanation: **Explanation:** Acute Respiratory Distress Syndrome (ARDS) is characterized by diffuse alveolar-capillary damage leading to non-cardiogenic pulmonary edema [1]. The pathophysiology involves an inflammatory trigger that increases permeability, causing protein-rich fluid to leak into the alveoli. **Why Malignant Hypertension is the correct answer:** Malignant hypertension (hypertensive emergency) typically causes **cardiogenic pulmonary edema**. The mechanism is hemodynamic: extreme systemic vascular resistance leads to left ventricular strain and increased pulmonary capillary hydrostatic pressure. Unlike ARDS, the alveolar-capillary membrane remains intact initially, and the edema fluid is transudative (low protein) rather than exudative [2]. **Analysis of Incorrect Options:** * **Smoke Inhalation:** This is a direct lung injury. Toxic chemicals and heat cause chemical pneumonitis and direct damage to the alveolar epithelium, a classic trigger for ARDS. * **Gastric Aspiration:** One of the most common causes of ARDS. The low pH of gastric acid causes immediate chemical burns to the lung parenchyma, triggering a massive inflammatory response. * **Viral Pneumonia:** A common infectious cause of ARDS (e.g., Influenza, COVID-19). The virus infects type II pneumocytes, leading to diffuse alveolar damage (DAD). **NEET-PG High-Yield Pearls:** * **Berlin Criteria for ARDS:** 1) Acute onset (within 1 week); 2) Bilateral opacities on imaging; 3) Respiratory failure not fully explained by heart failure (PCWP < 18 mmHg); 4) PaO2/FiO2 ratio < 300 [1]. * **Pathological Hallmark:** Diffuse Alveolar Damage (DAD) with the formation of **Hyaline Membranes**. * **Most common cause:** Sepsis (indirect injury) is the overall most common cause of ARDS.
Question 595: What is the gold standard for the diagnosis of pulmonary embolism?
- A. Chest X-ray
- B. Pulmonary angiography (Correct Answer)
- C. Ventilation perfusion scintiscan
- D. CT scan
Explanation: The diagnosis of Pulmonary Embolism (PE) involves a tiered approach ranging from clinical probability scores to advanced imaging. [1] **Why Pulmonary Angiography is the Gold Standard:** Pulmonary angiography is considered the **gold standard** because it provides the highest spatial resolution and allows for direct visualization of intraluminal filling defects or "cutoff" signs in the pulmonary arterial tree. It is an invasive procedure involving catheterization and contrast injection. While it is the definitive reference standard against which all other tests are measured, it is rarely performed today due to its invasive nature and the high accuracy of non-invasive alternatives. **Analysis of Incorrect Options:** * **A. Chest X-ray:** Usually normal or shows non-specific signs (e.g., atelectasis). Specific signs like **Westermark sign** (focal oligemia) or **Hampton’s hump** (wedge-shaped opacity) are rare and not diagnostic. [1] * **C. Ventilation-Perfusion (V/Q) Scans:** Useful when CT is contraindicated (e.g., renal failure or contrast allergy). It provides a probability (High, Intermediate, Low) rather than a definitive diagnosis. [1] * **D. CT Scan (CTPA):** Computed Tomographic Pulmonary Angiography is the **investigation of choice** and the most commonly used first-line test in clinical practice. However, it is not the "gold standard" in a strictly academic/pathological sense. [1] **NEET-PG High-Yield Pearls:** * **Investigation of Choice:** CTPA. [1] * **Gold Standard:** Pulmonary Angiography. * **Best Initial Test:** Chest X-ray (to rule out other causes of chest pain/dyspnea). [1] * **ECG Finding:** Most common is Sinus Tachycardia; most specific is **S1Q3T3** (sign of acute right heart strain). [1] * **D-Dimer:** High negative predictive value; used to rule out PE in low-probability patients.
Question 596: Caplan's syndrome is characterized by pneumoconiosis with which of the following conditions?
- A. Lymphadenopathy
- B. Congestive cardiac failure
- C. Rheumatoid arthritis (Correct Answer)
- D. HIV
Explanation: **Explanation:** **Caplan’s Syndrome** (also known as Rheumatoid Pneumoconiosis) is a clinical entity defined by the coexistence of **Rheumatoid Arthritis (RA)** and **Pneumoconiosis** (most commonly Coal Worker’s Pneumoconiosis, though it can occur with silicosis or asbestosis) [1]. 1. **Why Rheumatoid Arthritis is Correct:** The underlying pathophysiology involves an exaggerated inflammatory response. In patients with a rheumatoid diathesis, the inhalation of inorganic dust triggers the formation of multiple, well-defined "Caplan nodules" (0.5 to 5 cm in diameter) in the lungs [1]. These nodules are histologically similar to necrobiotic rheumatoid nodules found in the skin but have a peripheral zone of inflammation related to dust deposition [3]. Importantly, these nodules can appear before, during, or after the onset of joint symptoms [2]. 2. **Why Other Options are Incorrect:** * **Lymphadenopathy:** While common in sarcoidosis or silicosis (eggshell calcification), it is not the defining feature of Caplan’s syndrome. * **Congestive Cardiac Failure (CCF):** Chronic pneumoconiosis can lead to Cor Pulmonale (Right Heart Failure), but this is a complication of advanced lung disease, not a component of Caplan’s syndrome. * **HIV:** There is no specific syndromic association between HIV and pneumoconiosis. **High-Yield Clinical Pearls for NEET-PG:** * **Radiology:** Characterized by multiple, bilateral, peripheral "crop" of nodules on a background of mild pneumoconiosis. * **Commonest Dust:** Coal dust is the most frequent culprit [1]. * **Differential:** Must be distinguished from **Erasmus Syndrome** (Systemic Sclerosis + Silicosis). * **Prognosis:** The nodules may cavitate, calcify, or remain stable; however, the presence of RA often signifies a more aggressive inflammatory profile.
Question 597: True about pleural effusion?
- A. Amylase content is usually high in pancreatic effusion (Correct Answer)
- B. Bilateral effusion is due to congestive cardiac failure
- C. TB bacilli can be isolated if it is due to TB
- D. Hemorrhagic effusion is due to malignancy
Explanation: Explanation: 1. Why Option A is Correct: Pleural fluid amylase levels are considered elevated when they exceed the upper limit of normal for serum amylase or the fluid-to-serum amylase ratio is >1.0. High amylase is a hallmark of pancreatic pleural effusion (caused by acute/chronic pancreatitis or pancreatic pseudocyst), where levels can reach thousands. Other causes include esophageal rupture (salivary amylase) and certain malignancies (adenocarcinoma). 2. Why Other Options are Incorrect: * Option B: While Congestive Cardiac Failure (CCF) is the most common cause of bilateral effusion, it is not the only cause. Bilateral effusions can also occur in cirrhosis, nephrotic syndrome, and systemic lupus erythematosus (SLE). Therefore, saying it is "due to CCF" is an overgeneralization. * Option C: In Tuberculous pleurisy, the yield of TB bacilli in pleural fluid via direct microscopy (AFB stain) is extremely low (<5%), and culture yield is only about 20-40% [1]. Diagnosis usually relies on pleural biopsy, high ADA levels (>40 U/L), or PCR. * Option D: Hemorrhagic effusion is commonly associated with malignancy, but it is not pathognomonic [1]. It can also be seen in pulmonary embolism with infarction, trauma, and asbestos-related diseases [1]. Clinical Pearls for NEET-PG: * Light’s Criteria: Used to differentiate Exudate from Transudate (Protein ratio >0.5, LDH ratio >0.6, or Fluid LDH >2/3rd upper limit of serum) [1]. * Low Glucose (<60 mg/dL): Seen in Rheumatoid arthritis (characteristically very low), Empyema, Malignancy, and TB. * pH <7.2: Indicates a complicated parapneumonic effusion requiring a chest tube (intercostal drainage) [1]. * ADA (Adenosine Deaminase): High sensitivity for TB; if >40-70 U/L, suspect Tuberculosis in endemic areas.
Question 598: A chronic smoker presents with cough and hemoptysis. The physician informs the patient that they have the most malignant type of bronchogenic carcinoma. Which type is it?
- A. Squamous cell carcinoma
- B. Small cell carcinoma (Correct Answer)
- C. Large cell carcinoma
- D. Adenocarcinoma
Explanation: **Explanation:** **Small Cell Carcinoma (SCLC)** is considered the most malignant type of bronchogenic carcinoma due to its extremely rapid doubling time, high growth fraction, and early widespread metastasis. By the time of diagnosis, most patients already have micrometastatic disease, making surgical resection rarely an option [1]. It is strongly associated with cigarette smoking and originates from neuroendocrine (Kulchitsky) cells. **Why the other options are incorrect:** * **Squamous Cell Carcinoma:** While also strongly linked to smoking and central in location, it tends to stay localized longer and spreads to regional lymph nodes before distant sites. It is characterized by keratin pearls and intercellular bridges. * **Adenocarcinoma:** This is the most common type of lung cancer overall (especially in non-smokers and women). While it can be aggressive, its growth rate is generally slower than SCLC. * **Large Cell Carcinoma:** This is an undifferentiated epithelial tumor that grows rapidly and metastasizes early, but it does not match the extreme virulence and neuroendocrine aggressiveness of SCLC. **High-Yield Clinical Pearls for NEET-PG:** 1. **Location:** SCLC and Squamous cell carcinoma are typically **Central** (hilar), whereas Adenocarcinoma is **Peripheral**. 2. **Paraneoplastic Syndromes:** SCLC is classically associated with **SIADH** (hyponatremia), **ACTH** (Cushing syndrome), and **Lambert-Eaton Myasthenic Syndrome** [2]. 3. **Treatment:** Because it is "most malignant" and disseminated at onset, the treatment of choice for SCLC is **Chemotherapy/Radiotherapy**, not surgery [1]. 4. **Markers:** SCLC stains positive for neuroendocrine markers like **Chromogranin A, Synaptophysin, and CD56**. [3] Although it may be caused by bronchitic infection, haemoptysis in a smoker should always be investigated to exclude a bronchial carcinoma.
Question 599: Which of the following is a contributory factor for developing cor-pulmonale in chronic bronchitis?
- A. Hypoxia (Correct Answer)
- B. Hypercapnea
- C. Acidosis
- D. Alkalosis
Explanation: Explanation: Cor-pulmonale is defined as right ventricular hypertrophy and/or dilatation (and eventually failure) secondary to pulmonary hypertension caused by diseases of the lung parenchyma or pulmonary vasculature. Why Hypoxia is the correct answer: In chronic bronchitis, the primary driver of pulmonary hypertension is Hypoxic Pulmonary Vasoconstriction (HPV). When alveolar oxygen tension ($PAO_2$) falls, the pulmonary arterioles undergo vasoconstriction to divert blood flow to better-ventilated areas [2]. In chronic bronchitis, this hypoxia is widespread, leading to generalized vasoconstriction, increased pulmonary vascular resistance (PVR), and subsequent right ventricular strain [2]. Chronic hypoxia also leads to vascular remodeling (intimal thickening and smooth muscle hypertrophy), further fixing the hypertension. Analysis of Incorrect Options: * B. Hypercapnea: While elevated $CO_2$ levels are common in chronic bronchitis (Type 2 Respiratory Failure), hypercapnea itself is a weak vasoconstrictor compared to hypoxia [3]. Its main role is contributing to respiratory acidosis. * C. Acidosis: Respiratory acidosis (low pH) can augment hypoxic vasoconstriction, but it is considered a synergistic or aggravating factor rather than the primary "contributory factor" or initiator of the pathology. * D. Alkalosis: Alkalosis actually acts as a pulmonary vasodilator and would theoretically decrease pulmonary artery pressure, making it the opposite of a contributory factor. High-Yield Clinical Pearls for NEET-PG: * Gold Standard Diagnosis: Right heart catheterization (showing Mean Pulmonary Artery Pressure >20 mmHg at rest). * ECG Findings: "P-pulmonale" (tall, peaked P waves in lead II), right axis deviation, and R/S ratio >1 in V1. * Management Tip: Continuous oxygen therapy is the only intervention proven to improve survival in these patients by reversing hypoxic vasoconstriction and reducing PVR [1].
Question 600: Which of the following is NOT associated with pulmonary arterial hypertension?
- A. Interstitial lung disease
- B. Left ventricular hypertrophy (Correct Answer)
- C. Mitral Stenosis
- D. Cor pulmonale
Explanation: **Explanation:** The classification of Pulmonary Hypertension (PH) is divided into five groups based on etiology. Understanding these groups is key to identifying the correct answer. **Why Left Ventricular Hypertrophy (LVH) is the correct answer:** Pulmonary Arterial Hypertension (PAH) specifically refers to **WHO Group 1 PH**, which is characterized by primary disease of the small pulmonary arteries (pre-capillary PH). **Left Ventricular Hypertrophy (LVH)** is a consequence of systemic hypertension or aortic stenosis and leads to left-sided heart failure. This falls under **WHO Group 2 PH** (PH due to left heart disease). In Group 2, the pathology is "post-capillary" due to back-pressure from the left atrium, which is distinct from the "arterial" pathology of Group 1. **Analysis of Incorrect Options:** * **Interstitial Lung Disease (ILD):** Falls under **WHO Group 3**. Chronic hypoxia in ILD leads to pulmonary vasoconstriction and remodeling, causing PH [1]. * **Mitral Stenosis:** A classic cause of **WHO Group 2** PH. While it is "venous" or "post-capillary" PH, it is a well-known cause of elevated pulmonary pressures. * **Cor Pulmonale:** This is defined as right ventricular hypertrophy and failure resulting from diseases of the lungs or pulmonary vasculature (PH) [1]. Therefore, it is a direct **consequence** and clinical manifestation associated with chronic PH [1]. **NEET-PG High-Yield Pearls:** * **WHO Group 1 (PAH):** Includes Idiopathic, Heritable (BMPR2 mutation), and drug-induced (Aminorex, Fenfluramine). * **Hemodynamic Definition:** PH is now defined as Mean Pulmonary Artery Pressure **(mPAP) > 20 mmHg** (revised from 25 mmHg). * **Drug of Choice:** For PAH with a positive vasaoreactivity test, **Calcium Channel Blockers** are used. For others, Bosentan (Endothelin antagonist) or Sildenafil (PDE-5 inhibitor) are common. * **Gold Standard Diagnosis:** Right Heart Catheterization [1].
Practice by Chapter
Obstructive Airway Diseases (Asthma, COPD)
Practice Questions
Interstitial Lung Diseases
Practice Questions
Pulmonary Infections
Practice Questions
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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