Respiratory Diseases Practice Questions

Q: 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?

Bronchiolitis. ***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.

Q: 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?

Cystic fibrosis. ***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.

Q: 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?

Pleural Effusion. ***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.

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

Cystic fibrosis. ***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.

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

Inhaled epinephrine. ***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**.

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

Asthma. ***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.

Q: Which of the following is the most common cause of pneumonia in a 2-year-old child?

Streptococcus pneumoniae. ***Streptococcus pneumoniae*** - **Streptococcus pneumoniae** is the **most common cause of bacterial pneumonia** in children aged 2 months to 5 years, including 2-year-olds. - Remains the leading bacterial pathogen causing community-acquired pneumonia in this age group despite pneumococcal vaccination. - Typically presents with **lobar pneumonia**, high fever, and may be associated with **pleural effusion** or empyema in severe cases. - The **13-valent pneumococcal conjugate vaccine (PCV13)** has reduced incidence but S. pneumoniae remains the predominant bacterial cause. *RSV* - **Respiratory Syncytial Virus (RSV)** is the most common cause of **bronchiolitis** and lower respiratory tract infections in **infants**, particularly those aged **2-8 months**. - By age 2 years, RSV remains a cause of viral pneumonia but is significantly less common than in infancy. - When it does occur at this age, it tends to be less severe than in younger infants. *Haemophilus influenzae* - **Non-typeable Haemophilus influenzae** can cause pneumonia but is less common than S. pneumoniae. - **Haemophilus influenzae type b (Hib)** vaccine has dramatically reduced invasive Hib disease, including pneumonia. - Now accounts for a much smaller proportion of childhood pneumonia cases in vaccinated populations. *Mycoplasma pneumoniae* - **Mycoplasma pneumoniae** is a common cause of **atypical pneumonia** in **school-aged children** (>5 years) and adolescents. - Uncommon in children under 5 years of age, though can occasionally occur. - Presents with gradual onset, dry cough, and extrapulmonary manifestations (rash, myalgias).

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

Administer systemic corticosteroids. ***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.

Q: A 5-year-old girl with asthma is brought to the clinic with a history of recurrent wheezing and a recent chest infection. She has a high IgE level. Which test should be considered for diagnosing allergic bronchopulmonary aspergillosis (ABPA)?

Aspergillus-specific IgE test. ***Aspergillus-specific IgE test*** - **Aspergillus-specific IgE** (or ImmunoCAP to *Aspergillus fumigatus*) is a **primary diagnostic criterion** for ABPA and is the preferred first-line serological test. - A **positive result** confirms sensitization to *Aspergillus*, a key factor in ABPA diagnosis, and is more specific than total IgE measurement. - This test is **non-invasive, standardized, and quantifiable**, making it ideal for initial diagnostic workup in pediatric patients with suspected ABPA. *Skin prick test* - While a **skin prick test** to *Aspergillus fumigatus* can indicate immediate hypersensitivity and is included in diagnostic criteria, it is **less specific** than Aspergillus-specific IgE testing. - Skin testing requires expertise, can cause patient discomfort (especially in children), and may yield **false positives** in patients with general atopy. - Modern guidelines increasingly favor serological testing over skin prick testing as the initial diagnostic approach. *Sputum culture* - While *Aspergillus* can be cultured from sputum, its isolation alone does not confirm ABPA, as it can be a **saprophyte** in the airways of asthmatic patients. - A positive sputum culture is a supportive finding but lacks the specificity required for definitive ABPA diagnosis. *Bronchoalveolar lavage* - **Bronchoalveolar lavage (BAL)** may show **eosinophilia** and *Aspergillus* hyphae, but it's an **invasive procedure** not typically used as a first-line diagnostic test for ABPA. - BAL is usually reserved for cases where other diagnostic methods are inconclusive or to rule out alternative diagnoses.

Question 1

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?

Accepted Answer

Bronchiolitis

Answer

Asthma

Answer

Pneumonia

Answer

Cystic fibrosis

Question 2

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?

Accepted Answer

Cystic fibrosis

Answer

Primary ciliary dyskinesia

Answer

Bronchopulmonary dysplasia

Answer

Asthma

Question 3

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?

Accepted Answer

Pleural Effusion

Answer

Asthma

Answer

Pneumonia

Answer

Pneumothorax

Question 4

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

Accepted Answer

Cystic fibrosis

Answer

Celiac disease

Answer

Lactose intolerance

Answer

Crohn's disease

Question 5

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

Accepted Answer

Inhaled epinephrine

Answer

Oral antibiotics

Answer

Oral dexamethasone

Answer

Nebulized budesonide

Question 6

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

Accepted Answer

Asthma

Answer

Tuberculosis

Answer

GERD

Answer

Foreign body aspiration

Question 7

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.

Accepted Answer

Trial of bronchodilators + monitor

Answer

Empiric CF therapy

Answer

High-calorie diet + Vit ADEK supplementation

Answer

Pulmonary function testing

Question 8

Which of the following is the most common cause of pneumonia in a 2-year-old child?

Accepted Answer

Streptococcus pneumoniae

Answer

Haemophilus influenzae

Answer

Mycoplasma pneumoniae

Answer

RSV

Question 9

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

Accepted Answer

Administer systemic corticosteroids

Answer

Increase the frequency of bronchodilator therapy

Answer

Start long-term control with inhaled corticosteroids

Answer

Prescribe a course of antibiotics

Question 10

A 5-year-old girl with asthma is brought to the clinic with a history of recurrent wheezing and a recent chest infection. She has a high IgE level. Which test should be considered for diagnosing allergic bronchopulmonary aspergillosis (ABPA)?

Accepted Answer

Aspergillus-specific IgE test

Answer

Skin prick test

Answer

Sputum culture

Answer

Bronchoalveolar lavage

Respiratory Diseases — MCQs

Respiratory Diseases — MCQs

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