Pulmonology Practice Questions

Q: Which pattern is seen in pulmonary function tests in a patient with interstitial lung disease?

FEV1/FVC ratio increases and DLCO decreases. **Explanation:** Interstitial Lung Disease (ILD) is the classic prototype of a **Restrictive Lung Disease**. In these conditions, the lung parenchyma becomes stiff and non-compliant due to fibrosis, leading to specific changes in Pulmonary Function Tests (PFTs). 1. **FEV1/FVC Ratio:** In restrictive diseases, both the Forced Expiratory Volume in 1 second (FEV1) and the Forced Vital Capacity (FVC) decrease. However, because the elastic recoil of the fibrotic lung is increased, the airways are held open wider (radial traction), allowing air to be expelled rapidly. Consequently, the FVC drops more significantly than the FEV1, causing the **FEV1/FVC ratio to increase or remain normal** (typically >0.7 or 70%). 2. **DLCO (Diffusion Capacity):** The hallmark of ILD is the thickening of the alveolar-capillary membrane and the destruction of the alveolar surface area. This creates a physical barrier to gas exchange, leading to a **decreased DLCO**. **Analysis of Incorrect Options:** * **Option A:** Incorrect because DLCO must decrease due to the thickened membrane. * **Option C:** This pattern (Decreased Ratio and Decreased DLCO) is characteristic of **Emphysema**, where airway obstruction (low ratio) is combined with alveolar wall destruction (low DLCO). * **Option D:** This pattern (Decreased Ratio and Increased DLCO) can be seen in **Asthma** (during acute exacerbations) or conditions like alveolar hemorrhage. **High-Yield Clinical Pearls for NEET-PG:** * **Restrictive Pattern:** ↓ TLC, ↓ FVC, ↓ FRC, and **Normal/↑ FEV1/FVC ratio**. * **Obstructive Pattern:** ↓ FEV1, ↓ FEV1/FVC ratio (<0.7), and ↑ TLC (hyperinflation). * **DLCO in Obstruction:** It is **decreased in Emphysema** but **Normal/Increased in Asthma**. * **Compliance:** ILD is characterized by **decreased lung compliance** (stiff lungs).

Q: Bronchiolitis obliterans is suggested by all findings except:

Diffuse infiltrates seen on chest X-ray. **Explanation:** **Bronchiolitis Obliterans (BO)** is a chronic obstructive lung disease characterized by the fibrotic narrowing or complete occlusion of the small airways (bronchioles). **Why Option D is the Correct Answer:** In BO, the primary pathology is airway obstruction rather than alveolar filling. Therefore, the characteristic radiographic finding is **hyperlucency** (due to air trapping) and **vascular pruning**, rather than diffuse infiltrates. Diffuse infiltrates are more characteristic of acute infectious pneumonia or interstitial lung diseases, not the chronic obstructive remodeling seen in BO. **Analysis of Incorrect Options:** * **Option A (Hyperlucency):** This is a hallmark finding. As bronchioles become obliterated, air becomes trapped distally (check-valve mechanism), leading to hyperinflation and increased radiolucency on X-ray. * **Option B (Obstructive pattern):** Since BO involves the narrowing of small airways, Pulmonary Function Tests (PFTs) characteristically show a **fixed obstructive pattern** (decreased FEV1 and FEV1/FVC ratio) that does not respond to bronchodilators. * **Option C (Sequelae of Adenovirus):** Post-infectious BO is most commonly associated with **Adenovirus (types 3, 7, and 21)**. Other causes include Mycoplasma pneumoniae, measles, and graft-versus-host disease (GVHD) post-transplant. **NEET-PG High-Yield Pearls:** * **Swyer-James (MacLeod) Syndrome:** A classic manifestation of post-infectious BO where one lung or lobe appears hyperlucent and small with a small pulmonary artery. * **HRCT Finding:** The "gold standard" imaging finding is the **Mosaic Perfusion Pattern** (areas of decreased attenuation representing air trapping). * **Diagnosis:** Often clinical, based on a history of severe lower respiratory infection followed by persistent wheezing and obstruction unresponsive to therapy.

Q: What is the first investigation to be done for a patient with suspected interstitial lung disease?

Chest X-ray. **Explanation:** In the diagnostic workup of Interstitial Lung Disease (ILD), the **Chest X-ray (CXR)** is the **first/initial investigation** to be performed [1]. While it has low sensitivity (up to 10% of patients with biopsy-proven ILD may have a normal CXR), it serves as a crucial screening tool to rule out other pathologies like pneumonia or pneumothorax and provides a baseline for the patient. The classic finding on CXR is a "reticular" or "reticulonodular" pattern, often with reduced lung volumes [1]. **Analysis of Options:** * **High-Resolution Computed Tomography (HRCT):** This is the **Gold Standard** and the **investigation of choice** for diagnosing ILD [1]. It provides detailed visualization of the lung parenchyma (e.g., honeycombing, ground-glass opacities) [1]. However, it is not the *first* step due to higher cost and radiation exposure compared to a CXR. * **Multi-Detector Computed Tomography (MDCT):** While MDCT allows for rapid imaging and high-quality reconstructions, HRCT remains the specific protocol required for evaluating the fine details of the interstitium. * **Spirometry:** This is a functional assessment, not an imaging modality. In ILD, it typically shows a **Restrictive Pattern** (decreased FVC, decreased TLC, and a normal or increased FEV1/FVC ratio) [1]. It is used for staging and monitoring, not as the initial diagnostic step. **High-Yield Clinical Pearls for NEET-PG:** * **Initial Investigation:** Chest X-ray. * **Investigation of Choice (IOC):** HRCT [1]. * **Most Specific Finding on HRCT:** Honeycombing (pathognomonic for Usual Interstitial Pneumonia/UIP) [1]. * **PFT Pattern:** Restrictive lung disease with **decreased DLCO** (often the earliest functional abnormality) [1]. * **Most common symptom:** Progressive exertional dyspnea and dry cough [1].

Q: In an asthma patient, a positive bronchodilator reversibility test is indicated by:

Increase in FEV1 > 12% after SABA inhalation. The diagnosis of asthma relies on demonstrating **variable expiratory airflow limitation**. The bronchodilator reversibility (BDR) test is the gold standard for this. **1. Why Option B is Correct:** According to GINA (Global Initiative for Asthma) guidelines, a positive bronchodilator response in adults is defined as an **increase in FEV1 of >12% AND >200 mL** from the baseline, measured 10–15 minutes after inhaling a Short-Acting Beta-2 Agonist (SABA), such as 200–400 mcg of Salbutamol [1]. This significant improvement indicates that the airway obstruction is reversible, a hallmark of asthma that distinguishes it from most cases of COPD. **2. Why Other Options are Incorrect:** * **Option A (>5%):** This is within the range of normal breath-to-breath variation and lacks the specificity required to diagnose pathological airway hyperresponsiveness. * **Options C & D (>25% and >50%):** While these values would technically be "positive," they are far too high to serve as the diagnostic threshold. Setting the bar this high would result in a massive number of false negatives, missing most asthma patients. **High-Yield Clinical Pearls for NEET-PG:** * **In Children:** A positive BDR is often defined simply as an increase in FEV1 >12% predicted. * **COPD vs. Asthma:** While asthma is characterized by *reversible* obstruction, COPD typically shows *irreversible* or only partially reversible obstruction (FEV1/FVC ratio remains 10%** [1]. * **False Negatives:** A negative BDR test does not rule out asthma; the test may need to be repeated during a symptomatic period or confirmed via a Bronchial Provocation Test (e.g., Methacholine challenge) [1].

Q: Which of the following genes is associated with familial pulmonary arterial hypertension?

BMPR2. ### Explanation **Correct Option: A. BMPR2** Pulmonary Arterial Hypertension (PAH) is characterized by the remodeling of small pulmonary arteries, leading to increased vascular resistance. The most common genetic cause of **Familial PAH (Group 1)** is a mutation in the **Bone Morphogenetic Protein Receptor Type 2 (BMPR2)** gene, found in approximately 75-80% of familial cases and 20% of idiopathic cases. BMPR2 is a member of the TGF-̢ receptor superfamily; its deficiency leads to the proliferation of vascular smooth muscle cells and inhibition of apoptosis, resulting in the characteristic "plexiform lesions." **Incorrect Options:** * **B. VEGF (Vascular Endothelial Growth Factor):** While VEGF is involved in angiogenesis and its expression is altered in PAH, it is not the primary genetic driver for familial inheritance. * **C. ̡1-antitrypsin:** Mutations in the *SERPINA1* gene lead to ̡1-antitrypsin deficiency, which primarily causes **panacinar emphysema** and liver cirrhosis, not Group 1 PAH. * **D. CFTR:** Mutations in the *CFTR* gene cause **Cystic Fibrosis**. While chronic lung disease in CF can lead to secondary pulmonary hypertension (Group 3), it is not the cause of familial PAH. **High-Yield Clinical Pearls for NEET-PG:** * **Inheritance:** BMPR2 mutations follow an **Autosomal Dominant** pattern with **incomplete penetrance** (only ~20% of carriers develop the disease). * **Other Genes:** Less common mutations include *ALK-1* and *Endoglin* (associated with Hereditary Hemorrhagic Telangiectasia). * **Diagnosis:** The gold standard for diagnosis of PAH is **Right Heart Catheterization** (Mean Pulmonary Artery Pressure >20 mmHg at rest). * **Histology:** The pathognomonic finding in PAH is the **Plexiform Lesion**.

Q: A stony dull note on percussion is characteristic of which of the following conditions?

Pleural effusion. The correct answer is **Pleural effusion**. **1. Why Pleural Effusion is Correct:** Percussion is a clinical technique used to assess the density of underlying tissue. In **pleural effusion**, the accumulation of fluid in the pleural space creates a physical barrier between the chest wall and the air-filled lung [1]. Fluid is significantly denser than air or consolidated tissue; when percussed, it produces a **"stony dull"** note—a flat, high-pitched sound with a characteristic lack of resonance, often described as percussing a stone or a heavy table [4]. **2. Analysis of Incorrect Options:** * **Consolidation (B):** In pneumonia, air in the alveoli is replaced by exudate [3]. This produces a **dull** note (similar to percussing the liver), but it is not "stony" because some transmission through the bronchial tree remains. * **Pleurisy (C):** This refers to inflammation of the pleura. In the early stages (dry pleurisy), percussion is typically **normal (resonant)**, though it is associated with a pleural friction rub on auscultation [2]. * **Tuberculosis Cavity (D):** A large, empty, superficial cavity typically produces a **hyper-resonant** or **tympanitic** note (specifically a "cracked-pot" sound or *bruit de pot fêlé*) due to the increased air-to-tissue ratio. **3. Clinical Pearls for NEET-PG:** * **Shifting Dullness:** A hallmark of large pleural effusions; the level of dullness changes with the patient's position. * **Ellis S-shaped Curve:** The upper border of dullness in a medium-sized pleural effusion is highest in the axilla. * **Hyper-resonance:** Seen in Pneumothorax and Emphysema [2]. * **Dullness vs. Stony Dullness:** If the question mentions "dullness" without "stony," think Consolidation or Collapse; if "stony" is specified, it is pathognomonic for Fluid (Effusion/Empyema).

Q: A 53-year-old man, a smoker for 35 years at a 2-pack-a-day rate, presents with a persistent cough and dyspnea. A chest X-ray reveals an increased anterior-posterior diameter, flattened diaphragms, and air trapping, ruling out malignancy. The patient is informed that his condition is irreversible and that smoking cessation is crucial to halt disease progression. At the molecular level, this disease is caused by which one of the following?

Decreased alpha-1-antitrypsin activity in the lung. ### Explanation The clinical presentation (heavy smoking history, increased AP diameter, flattened diaphragms, and air trapping [2]) is classic for **Emphysema**, a component of Chronic Obstructive Pulmonary Disease (COPD) [1]. **1. Why the Correct Answer is Right:** The underlying pathophysiology of emphysema is based on the **Protease-Antiprotease Imbalance Hypothesis**. In a healthy lung, **Alpha-1-Antitrypsin (AAT)** acts as a major antiprotease that inhibits **Neutrophil Elastase** (a serine protease). Smoking triggers chronic inflammation, leading to an influx of neutrophils and macrophages that release elastase. Simultaneously, oxidants in cigarette smoke inactivate AAT [3]. This results in **decreased AAT activity**, allowing elastase to unchecked destroy the elastic fibers of the alveolar walls, leading to permanent airspace enlargement and loss of elastic recoil [3]. **2. Why the Incorrect Options are Wrong:** * **Options A & B:** Trypsin is a digestive enzyme produced by the pancreas. While AAT can inhibit trypsin in vitro (hence the name), the primary driver of lung destruction in emphysema is **Neutrophil Elastase**, not trypsin [3]. * **Option C:** Enhanced AAT activity would be protective against lung tissue destruction. The disease occurs specifically because the protective "buffer" of AAT is overwhelmed or deficient [3]. **3. NEET-PG High-Yield Pearls:** * **Centriacinar Emphysema:** Most common type; associated with smoking; primarily affects the **upper lobes**. * **Panacinar Emphysema:** Associated with **Alpha-1-Antitrypsin Deficiency** (genetic); primarily affects the **lower lobes**. * **Pink Puffers:** Classic description of emphysema patients (dyspneic, thin, using accessory muscles, but maintain near-normal oxygenation until late stages) [4]. * **Microscopy:** Characterized by thinned alveolar walls and "floating" septa due to septal destruction.

Question 1

Which of the following is an example of Type I respiratory failure?

Accepted Answer

ARDS

Answer

Cardiogenic shock

Answer

Atelectasis

Answer

Myasthenia gravis

Question 2

Which pattern is seen in pulmonary function tests in a patient with interstitial lung disease?

Accepted Answer

FEV1/FVC ratio increases and DLCO decreases

Answer

FEV1/FVC ratio increases and DLCO increases

Answer

FEV1/FVC ratio decreases and DLCO decreases

Answer

FEV1/FVC ratio decreases and DLCO increases

Question 3

A 50-year-old man presents with increasing dyspnea for the past 3 years, occasional cough, and minimal sputum production. Auscultation reveals hyper-resonant lungs and expiratory wheeze. Pulmonary function tests show increased total lung capacity (TLC) and slightly increased FVC, with decreased FEV1 and FEV1/FVC ratio. Arterial blood gas analysis reveals pH 7.35, pO2 60 mm Hg, and pCO2 48 mm Hg. What is the most likely diagnosis?

Accepted Answer

Centriacinar emphysema

Answer

Sarcoidosis

Answer

Diffuse alveolar damage

Answer

Chronic pulmonary embolism

Question 4

Bronchiolitis obliterans is suggested by all findings except:

Accepted Answer

Diffuse infiltrates seen on chest X-ray

Answer

Hyperlucency on chest X-ray

Answer

Obstructive pattern on pulmonary function test

Answer

Sequelae of Adenovirus infection

Question 5

What is the first investigation to be done for a patient with suspected interstitial lung disease?

Accepted Answer

Chest X-ray

Answer

High-Resolution Computed Tomography (HRCT)

Answer

Multi-Detector Computed Tomography (MDCT)

Answer

Spirometry

Question 6

In an asthma patient, a positive bronchodilator reversibility test is indicated by:

Accepted Answer

Increase in FEV1 > 12% after SABA inhalation

Answer

Increase in FEV1 > 5% after SABA inhalation

Answer

Increase in FEV1 > 25% after SABA inhalation

Answer

Increase in FEV1 > 50% after SABA inhalation

Question 7

Which of the following genes is associated with familial pulmonary arterial hypertension?

Accepted Answer

BMPR2

Answer

VEGF

Answer

a1-antitrypsin

Answer

CFTR

Question 8

A 55-year-old man, on bed rest for the past 10 days, complains of breathlessness and chest pain. His chest X-ray is normal. What is the next step in the investigation?

Accepted Answer

Lung ventilation–perfusion scan

Answer

Pulmonary arteriography

Answer

Pulmonary venous wedge angiography

Answer

Echocardiography

Question 9

A stony dull note on percussion is characteristic of which of the following conditions?

Accepted Answer

Pleural effusion

Answer

Consolidation

Answer

Pleurisy

Answer

Tuberculosis cavity

Question 10

A 53-year-old man, a smoker for 35 years at a 2-pack-a-day rate, presents with a persistent cough and dyspnea. A chest X-ray reveals an increased anterior-posterior diameter, flattened diaphragms, and air trapping, ruling out malignancy. The patient is informed that his condition is irreversible and that smoking cessation is crucial to halt disease progression. At the molecular level, this disease is caused by which one of the following?

Accepted Answer

Decreased alpha-1-antitrypsin activity in the lung

Answer

Enhanced trypsin activity in the lung

Answer

Decreased trypsin activity in the lung

Answer

Enhanced alpha-1-antitrypsin activity in the lung

Pulmonology — MCQs

Pulmonology — MCQs

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