Respiratory Diseases — MCQs

Respiratory Diseases Indian Medical PG Practice Questions and MCQs

Question 261: An 18-month-old child presents with fever, cough, and wheezing. A chest X-ray shows hyperinflation and patchy infiltrates. What is the most likely diagnosis?

A. Asthma
B. Bronchiolitis (Correct Answer)
C. Pneumonia
D. Cystic fibrosis

Explanation: ***Bronchiolitis*** - **Bronchiolitis** is the most common lower respiratory tract infection in children under 2 years old and presents with **fever**, **cough**, and **wheezing**, often following a viral upper respiratory infection (most commonly RSV). - Chest X-ray findings typically include **hyperinflation** (due to air trapping from small airway obstruction) and **patchy infiltrates** or peribronchial thickening, which are characteristic of this condition. - The age group (18 months) and clinical presentation are classic for bronchiolitis. *Asthma* - While asthma can present with **wheezing** and **cough**, it is less common in children under 2 years old as the first presentation. - Asthma typically lacks fever and is more episodic with identifiable triggers (allergens, exercise, cold air). - Chest X-ray in asthma may show hyperinflation but usually lacks the patchy infiltrates seen here. *Pneumonia* - Pneumonia typically presents with **high fever**, **productive cough**, and **localized infiltrates or consolidation** on chest X-ray rather than diffuse patchy infiltrates. - While bacterial pneumonia can cause cough and fever, the prominent **wheezing** and **hyperinflation** are more characteristic of bronchiolitis. - The diffuse nature of findings favors bronchiolitis over focal pneumonia. *Cystic fibrosis* - Cystic fibrosis is a **genetic disorder** that typically presents with **recurrent respiratory infections**, **failure to thrive**, and **malabsorption** with steatorrhea. - While it can cause chronic cough and wheezing, an acute presentation as described without prior history of recurrent infections, poor growth, or gastrointestinal symptoms makes this less likely. - CF is a chronic progressive condition rather than an acute illness.

Question 262: A 6-year-old boy presents with fever, cough, and difficulty breathing. On examination, there are decreased breath sounds on the right side and dullness to percussion. Chest X-ray shows blunting of the costophrenic angle. What is the most likely diagnosis?

A. Asthma
B. Pneumonia
C. Pneumothorax
D. Pleural Effusion (Correct Answer)

Explanation: ***Pleural Effusion*** - The combination of **decreased breath sounds** and **dullness to percussion** with **blunting of the costophrenic angle** on chest X-ray is diagnostic of pleural effusion. - Pleural effusion represents fluid accumulation in the pleural space, commonly seen as a **parapneumonic effusion** in pediatric respiratory infections. - The physical exam finding of **dullness to percussion** is the key distinguishing feature that indicates fluid rather than air-trapping or simple consolidation. *Pneumonia* - Pneumonia is likely the **underlying cause** and often presents with similar symptoms (fever, cough, difficulty breathing). - However, when **dullness to percussion** and **costophrenic angle blunting** are specifically noted, this indicates the presence of **pleural effusion** (often parapneumonic). - Pure pneumonia with consolidation may show **bronchial breath sounds** and **increased tactile fremitus**, but the marked dullness and imaging findings point to fluid collection. *Asthma* - Asthma typically presents with **wheezing** and **hyperresonance** to percussion due to air trapping, not dullness. - The primary pathophysiology in asthma is **bronchoconstriction**, which does not cause fluid accumulation or dullness to percussion. *Pneumothorax* - Pneumothorax involves air in the pleural space, leading to **hyperresonance** to percussion (not dullness) and severely **diminished breath sounds**. - The finding of **dullness** specifically rules out pneumothorax in favor of fluid or solid mass.

Question 263: A 10-month-old infant presents with a history of recurrent chest infections and has a sweat chloride level of 70 mmol/L. What is the most likely diagnosis?

A. Cystic fibrosis (Correct Answer)
B. Primary ciliary dyskinesia
C. Bronchopulmonary dysplasia
D. Asthma

Explanation: ***Cystic fibrosis*** - A **high sweat chloride level** (typically > 60 mmol/L) is the hallmark diagnostic criterion for cystic fibrosis (CF). - Recurrent chest infections are common in CF due to thick, sticky mucus obstructing airways and promoting **bacterial growth**. *Primary ciliary dyskinesia* - Characterized by **defects in ciliary structure or function**, leading to impaired mucus clearance and recurrent respiratory infections. - However, it is not associated with elevated sweat chloride levels. *Bronchopulmonary dysplasia* - A chronic lung disease that affects premature infants who received oxygen therapy or mechanical ventilation. - It involves **abnormal lung development** and persistent respiratory symptoms, but not high sweat chloride. *Asthma* - A chronic inflammatory disease of the airways, often characterized by **reversible airway obstruction** and hyperresponsiveness. - It presents with wheezing, coughing, and shortness of breath, but does not involve elevated sweat chloride or recurrent severe infections in infancy to this degree.

Question 264: A 5-year-old child presents with a history of failure to thrive, recurrent respiratory infections, and steatorrhea. What is the most likely diagnosis?

A. Celiac disease
B. Lactose intolerance
C. Cystic fibrosis (Correct Answer)
D. Crohn's disease

Explanation: ***Cystic fibrosis*** - This genetic disorder is characterized by a defect in the **CFTR protein**, leading to thick, viscous secretions in various organs. - The combination of **failure to thrive**, **recurrent respiratory infections** (due to thick mucus in the lungs), and **steatorrhea** (due to pancreatic insufficiency) is highly characteristic of cystic fibrosis. *Celiac disease* - This autoimmune disorder is triggered by **gluten ingestion**, causing damage to the small intestine. - While it can cause failure to thrive and steatorrhea, it typically does **not cause recurrent respiratory infections**. *Lactose intolerance* - This condition results from the inability to digest **lactose**, leading to gastrointestinal symptoms like bloating, gas, and diarrhea. - It would not typically cause **failure to thrive** (unless severe and prolonged malabsorption occurred) and **does not cause recurrent respiratory infections**. *Crohn's disease* - This is a type of **inflammatory bowel disease** that can affect any part of the gastrointestinal tract. - While it can cause failure to thrive due to malabsorption, it is **less common in 5-year-olds** to present with recurrent respiratory infections as a primary symptom.

Question 265: An infant with a barking cough and stridor at rest is suspected to have croup. What is the most effective initial treatment?

A. Oral antibiotics
B. Inhaled epinephrine (Correct Answer)
C. Oral dexamethasone
D. Nebulized budesonide

Explanation: ***Inhaled epinephrine*** - **Stridor at rest** indicates **moderate to severe croup** requiring immediate intervention. - **Inhaled epinephrine** provides **rapid relief** (within 10-30 minutes) by causing vasoconstriction and reducing mucosal edema in the upper airway. - It is the **most effective initial treatment** for children with stridor at rest or significant respiratory distress. - Should be administered along with **systemic corticosteroids** (dexamethasone) for sustained effect. *Oral dexamethasone* - **Dexamethasone** is an essential component of croup management and should be given to all patients. - However, it takes **4-6 hours** to show clinical effect, making it insufficient as sole **initial** treatment for moderate-severe croup. - It provides **sustained relief** and prevents symptom recurrence after epinephrine wears off. *Nebulized budesonide* - **Budesonide** is an alternative inhaled corticosteroid that can be used in croup. - While effective, it is not as rapid as **epinephrine** and not as convenient or well-studied as **oral dexamethasone**. - Generally reserved for situations where dexamethasone is not available or tolerated. *Oral antibiotics* - **Croup** is caused by **viral infections** (primarily parainfluenza virus), making antibiotics ineffective. - Antibiotics have no role in the management of uncomplicated croup and contribute to **antibiotic resistance**.

Question 266: Which of the following is the most common cause of chronic cough in children?

A. Asthma (Correct Answer)
B. Tuberculosis
C. GERD
D. Foreign body aspiration

Explanation: ***Asthma*** - **Asthma** is a very common chronic respiratory condition in children, and chronic cough, particularly at night or with exercise, is a hallmark symptom. - The cough in asthma is often **non-productive** and may be accompanied by **wheezing** or shortness of breath. *Tuberculosis* - While tuberculosis can cause chronic cough, it is generally **less common** than asthma in many developed regions unless there is increased prevalence or specific risk factors. - A cough due to tuberculosis is often associated with other systemic symptoms like **fever, weight loss, and night sweats**. *GERD* - **Gastroesophageal reflux disease (GERD)** can cause chronic cough, especially if acid reflux irritates the airways. - However, in children, **asthma** is generally a more prevalent cause of chronic cough compared to GERD. *Foreign body aspiration* - Foreign body aspiration typically presents with a **sudden onset** of coughing, choking, and respiratory distress, not usually a chronic cough developing over time. - The cough quality is often **paroxysmal and severe**, and there may be localized wheezing or diminished breath sounds.

Question 267: What is the standard method to confirm the diagnosis of cystic fibrosis in a child?

A. Genetic testing
B. Sweat chloride test (Correct Answer)
C. Chest X-ray
D. Pulmonary function tests

Explanation: ***Sweat chloride test*** - The **sweat chloride test** is the **gold standard** for diagnosing cystic fibrosis (CF) and measures the concentration of chloride in sweat. - A chloride concentration of **≥ 60 mEq/L** on two separate occasions is generally considered diagnostic for CF in children. *Genetic testing* - While genetic testing (for **CFTR mutations**) can confirm the diagnosis, it is often performed as a **next step** after a positive sweat test or in cases with an unclear sweat test result. - Not all **CFTR mutations** are routinely screened for, and some individuals with CF may have rare mutations not covered by standard panels. *Chest X-ray* - A chest X-ray can show signs of **lung damage** typical in CF, such as **bronchiectasis**, hyperinflation, or atelectasis, but it is **not diagnostic** for the disease itself. - It helps assess the **severity of lung involvement** rather than confirming the initial diagnosis. *Pulmonary function tests* - **Pulmonary function tests** (PFTs) measure **lung capacity** and airflow, often showing an **obstructive pattern** in CF patients. - PFTs assess the **severity and progression** of lung disease but cannot definitively diagnose CF.

Question 268: A 6-month-old male presents with a history of chronic cough, wheezing, and recurrent pneumonias. There is no failure to thrive, clubbing, or digital anomalies. Sweat chloride is 25 mmol/L, and genetic analysis is pending. Evaluate and suggest the most appropriate management.

A. Empiric CF therapy
B. High-calorie diet + Vit ADEK supplementation
C. Pulmonary function testing
D. Trial of bronchodilators + monitor (Correct Answer)

Explanation: ***Trial of bronchodilators + monitor*** - In this infant with **chronic cough, wheezing, and recurrent pneumonias**, the **sweat chloride of 25 mmol/L is borderline** (normal <30 mmol/L) and does **not confirm cystic fibrosis**. - Since **genetic analysis is pending** and typical CF features (failure to thrive, clubbing) are **absent**, the most prudent approach is **symptomatic treatment with bronchodilators** for the wheezing while **closely monitoring** the patient. - **Monitoring** allows time to obtain genetic results, consider repeat sweat chloride testing, and further evaluate the cause of **recurrent pneumonias** before committing to specific therapies. - This conservative approach avoids premature diagnostic commitment while addressing acute respiratory symptoms. *Empiric CF therapy* - Starting empiric CF therapy (pancreatic enzymes, chest physiotherapy, prophylactic antibiotics) is **not appropriate** without a confirmed diagnosis of cystic fibrosis. - The **sweat chloride is borderline** (not diagnostic), and key CF manifestations like **failure to thrive and clubbing are absent**. - Premature CF therapy could lead to unnecessary treatments and potential medication side effects without addressing the actual underlying cause. *High-calorie diet + Vit ADEK supplementation* - This intervention is indicated for **malabsorption and failure to thrive** seen in confirmed cystic fibrosis. - The patient is **not failing to thrive**, indicating adequate nutrition and no evidence of pancreatic insufficiency at present. - **Vitamin ADEK supplementation** addresses fat-soluble vitamin malabsorption in CF, but CF is not confirmed and there are no signs of malabsorption. *Pulmonary function testing* - **Pulmonary function tests cannot be reliably performed** in a **6-month-old infant** as they require patient cooperation and specific breathing maneuvers. - PFTs are typically used in children **≥5-6 years of age** who can follow instructions. - Infant pulmonary function testing exists but is specialized, not routinely available, and would not change immediate management in this clinical scenario.

Question 269: A 3-year-old with a severe asthma exacerbation is not responding to initial bronchodilator therapy. What is the next best step in management?

A. Increase the frequency of bronchodilator therapy
B. Administer systemic corticosteroids (Correct Answer)
C. Start long-term control with inhaled corticosteroids
D. Prescribe a course of antibiotics

Explanation: ***Administer systemic corticosteroids*** - Systemic corticosteroids are crucial for reducing **airway inflammation** in severe asthma exacerbations, leading to improved bronchodilator responsiveness. - They work by decreasing **mucosal edema** and mucus production, thus opening up the airways. *Increase the frequency of bronchodilator therapy* - While initial bronchodilator therapy is important, simply increasing its frequency when a patient is not responding may not address the underlying **inflammation** contributing to the severity. - Excessive bronchodilator use without addressing inflammation can lead to potential **side effects** like tachycardia and tremors. *Start long-term control with inhaled corticosteroids* - Long-term control inhaled corticosteroids are used for **maintenance therapy** in persistent asthma, not for acute, severe exacerbations. - Their effect takes time to develop and is not suitable for immediate relief in an **emergent situation**. *Prescribe a course of antibiotics* - Antibiotics are indicated only if there is evidence of a **bacterial infection**, which is not mentioned as a contributing factor in this asthma exacerbation. - Most asthma exacerbations are triggered by **viral infections** or environmental factors, not bacteria.

Question 270: Most common sign of LRTI [Lower respiratory tract infection] in children is

A. Chest indrawing
B. Tachypnea (Correct Answer)
C. Nasal flaring
D. Failure to feed well

Explanation: ***Tachypnea*** - **Tachypnea**, or abnormally rapid breathing, is the most common and earliest sign of a lower respiratory tract infection (LRTI) in children. - It reflects the body's attempt to compensate for impaired gas exchange due to lung inflammation or infection. *Chest indrawing* - **Chest indrawing** (or retractions) indicates increased work of breathing and is a sign of *severe* respiratory distress, rather than the most common initial sign. - While concerning, it suggests a more advanced stage of respiratory compromise. *Nasal flaring* - **Nasal flaring** is a sign of increased effort in breathing and suggests respiratory distress, but it is less common and often occurs later than tachypnea. - It is an attempt to reduce airway resistance by widening the nasal passages. *Failure to feed well* - **Failure to feed well** is a general sign of illness in infants and young children, often accompanying LRTI, but it is not specific to respiratory infection. - It can be a consequence of many illnesses and is not the primary indicator of respiratory compromise.

Practice by Chapter

Upper Respiratory Tract Infections

Practice Questions

Lower Respiratory Tract Infections

Practice Questions

Asthma Management

Practice Questions

Cystic Fibrosis

Practice Questions

Bronchiolitis

Practice Questions

Foreign Body Aspiration

Practice Questions

Sleep-Disordered Breathing

Practice Questions

Congenital Lung Malformations

Practice Questions

Pleural Diseases

Practice Questions

Tuberculosis in Children

Practice Questions

Chronic Lung Disease in Premature Infants

Practice Questions

Pulmonary Function Testing

Practice Questions

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