Respiratory Diseases Practice Questions

Q: A 2-month-old infant is brought to the pediatric clinic with a history of high-pitched inspiratory stridor that began shortly after birth. The mother notes that the sound is most noticeable when the baby is crying or feeding. Which of the following is true regarding the diagnosis?

Omega sign improves in the prone position. ***Omega sign improves in the prone position*** - The clinical presentation of chronic, high-pitched inspiratory stridor starting shortly after birth, which worsens with agitation or feeding, is classic for **laryngomalacia**. The hallmark finding on laryngoscopy is an omega-shaped (Ω) **epiglottis** that collapses inward during inspiration; placing the infant in a **prone position** often relieves airway obstruction by allowing the supraglottic tissues to fall forward. *Thumb sign improves in the supine position* - The **thumb sign** is a classic radiographic finding on a lateral neck X-ray indicative of **epiglottitis**, a medical emergency involving inflammation of the epiglottis. Laryngomalacia is a chronic, benign condition, whereas epiglottitis presents with acute onset drooling, tripod positioning, and fever, which are not described in this infant. *Steeple sign is characteristic* - The **steeple sign** seen on AP neck X-rays is diagnostic for **croup** (laryngotracheobronchitis), which typically presents with a barking cough and is caused by parainfluenza virus. This condition usually occurs in older infants and typically presents with acute symptoms rather than a chronic stridor persisting since birth. *Cherry-red epiglottis sign is characteristic* - A **cherry-red epiglottis** observed during examination is a specific sign of acute, bacterial **epiglottitis**, usually caused by *Haemophilus influenzae* type b. This condition presents with rapidly progressive respiratory distress and dysphagia, and looking in the throat is strictly contraindicated due to the risk of precipitating total airway obstruction.

Q: A patient is shown using a metered -dose inhaler as shown in the image. Which of the following statements about spacer use is correct?

Decreases drug wastage & reduces oropharyngeal deposition. ***Decreases drug wastage & reduces oropharyngeal deposition*** - Spacers act as a reservoir, allowing the medication particles to slow down and suspend in the device, which ensures that more **medication reaches the lower airways** rather than impacting the back of the throat. - By minimizing **oropharyngeal deposition**, spacers significantly reduce the risk of common side effects like **oral candidiasis** and dysphonia, particularly with inhaled corticosteroids. *Increases systemic absorption of the drug* - The primary goal of a spacer is to improve **local delivery** to the lungs, not to increase systemic uptake. - In fact, by reducing deposition in the oropharynx, the amount of drug swallowed and subsequently absorbed into the **systemic circulation** from the GI tract is typically **decreased**. *Makes inhaler technique more complicated and less effective* - Spacers actually simplify the **coordination** required between actuating the inhaler and inhaling, making the process much easier for patients, especially children and the elderly. - They are proven to **improve overall drug delivery efficacy** in patients who struggle with the

Q: Which among the following channels is affected in CFTR gene mutation?

Chloride. ***Chloride*** - The **CFTR gene** (Cystic Fibrosis Transmembrane Conductance Regulator) encodes a protein that functions as an **ATP-gated chloride channel** expressed in the epithelial cells of the lungs, pancreas, and sweat glands. - Mutations in this gene lead to defective **chloride transport**, resulting in thick, viscous secretions that cause the clinical manifestations of **cystic fibrosis**. *Potassium* - **Potassium channels** are vital for maintaining resting membrane potential and repolarization in cardiac and neural tissues, not for the pathogenesis of cystic fibrosis. - CFTR is specifically a transmembrane regulator for anions, not cations like potassium. *Sodium* - While sodium transport is dysregulated in cystic fibrosis (due to the **ENaC** channel becoming hyperactive because of the lack of inhibitory regulation by the CFTR protein), it is not the primary ion channel encoded by the CFTR gene. - The primary defect is the inability to transport **chloride** ions across the cell membrane, which secondarily impacts sodium and water movement. *Magnesium* - **Magnesium channels** (such as TRPM6 or TRPM7) regulate systemic magnesium homeostasis and intracellular signaling. - There is no involvement of magnesium transport in the pathophysiology associated with **CFTR gene mutations**.

Q: A patient develops acute respiratory distress, stridor, unilateral hyperinflation of the chest with decreased breath sounds on that side. What is the most likely cause?

Foreign body aspiration. ### Explanation The clinical presentation of **acute respiratory distress, stridor, and unilateral hyperinflation** is a classic triad for **Foreign Body Aspiration (FBA)**. **Why Foreign Body Aspiration is Correct:** When an object is aspirated, it often creates a **"check-valve" effect**. During inspiration, the airways dilate, allowing air to pass the object. During expiration, the airways narrow, trapping air distal to the foreign body. This leads to **obstructive emphysema (unilateral hyperinflation)** and decreased breath sounds on the affected side. Stridor indicates the object may be lodged in the upper airway or trachea, while localized wheezing or decreased air entry suggests a bronchial location (most commonly the right main bronchus). **Why Other Options are Incorrect:** * **Asthma:** Typically presents with bilateral diffuse wheezing and a history of atopy. It does not cause focal unilateral hyperinflation unless complicated by a secondary pneumothorax. * **Aspiration Pneumonia:** Usually presents with fever, cough, and crackles rather than acute stridor. Radiologically, it shows opacification/consolidation rather than hyperinflation. * **Pleural Effusion:** This would result in **stony dullness** on percussion and **collapsed/shifted lung** (mediastinal shift away from the lesion), but the affected side would show decreased expansion and opacification on X-ray, not hyperinflation. **High-Yield Clinical Pearls for NEET-PG:** * **Gold Standard Diagnosis & Management:** Rigid Bronchoscopy (both diagnostic and therapeutic). * **Most Common Site:** Right main bronchus (due to it being wider, shorter, and more vertical). * **Radiological Sign:** Mediastinal shift away from the affected side during expiration (due to air trapping). * **Age Group:** Most common in children aged 1–3 years (the "peanut" age).

Q: Pneumatocele is commonest in which of the following conditions?

Staphylococcal pneumonia. **Explanation:** **Staphylococcal pneumonia** is the correct answer because it is a necrotizing infection characterized by the production of toxins (such as Panton-Valentine Leukocidin) and enzymes that cause tissue destruction. This leads to the formation of **pneumatoceles**—thin-walled, air-filled tension cysts within the lung parenchyma. These occur due to a "check-valve" mechanism where air enters the necrotic area during inspiration but becomes trapped during expiration. While pneumatoceles are transient and usually resolve spontaneously, they are a classic radiological hallmark of *Staphylococcus aureus* infection in children. **Analysis of Incorrect Options:** * **Pneumococcal pneumonia (A):** Caused by *Streptococcus pneumoniae*, this typically presents as lobar consolidation. While it is the most common cause of bacterial pneumonia, it rarely causes cavitation or pneumatoceles. * **H. influenzae pneumonia (C):** Usually presents as bronchopneumonia or lobar involvement. While it can cause pleural effusions, pneumatocele formation is not a characteristic feature. * **Viral pneumonia (D):** Typically presents with interstitial infiltrates and hyperinflation. It does not cause the focal parenchymal necrosis required to form pneumatoceles. **NEET-PG High-Yield Pearls:** * **Most common complication** of Staphylococcal pneumonia: Empyema or Pyopneumothorax. * **Radiological triad for Staph pneumonia:** Bronchopneumonia, Pneumatoceles, and Pleural effusion/Empyema. * **Management of Pneumatocele:** Most are asymptomatic and require **conservative management** (observation), as they regress over weeks to months. Surgery is only indicated if they cause tension pneumothorax or become infected.

Q: A 1-year-old infant presents with biphasic stridor, barking cough, and difficulty in breathing for the past 3-4 days. The infant has a high-grade fever and an elevated leukocyte count. Which of the following statements regarding this clinical condition is not true?

Antibiotics are the mainstay of treatment.. ### Explanation The clinical presentation of barking cough, biphasic stridor, and respiratory distress in an infant is characteristic of **Croup (Laryngotracheobronchitis)**. **1. Why Option C is the Correct Answer (The "Not True" Statement):** Croup is primarily caused by **viruses**, most commonly the **Parainfluenza virus (Type 1 & 2)**. Since the etiology is viral, **antibiotics are not the mainstay of treatment**. Management focuses on airway maintenance using humidified oxygen, nebulized adrenaline (to reduce mucosal edema), and corticosteroids (Dexamethasone) to reduce inflammation. Antibiotics are only indicated if a secondary bacterial infection is suspected. **2. Analysis of Other Options:** * **Option A:** Epidemiologically, Croup shows a slight male preponderance, being more common in boys than girls. * **Option B:** The subglottic region is the narrowest part of the pediatric airway. Inflammation and edema in this specific area lead to the characteristic barking cough and stridor. * **Option C:** On an X-ray (Anteroposterior view), subglottic narrowing creates the classic **"Steeple Sign."** Lateral views often show **ballooning of the hypopharynx** as the child attempts to overcome the subglottic obstruction. **Clinical Pearls for NEET-PG:** * **Most common cause:** Parainfluenza Virus Type 1. * **Steeple Sign:** Seen on AP view of the neck (subglottic narrowing). * **Westley Croup Score:** Used to classify severity (Mild, Moderate, Severe). * **Drug of Choice:** Dexamethasone (0.15 to 0.6 mg/kg) is the mainstay to reduce the need for intubation. * **Differential Diagnosis:** Always rule out *Acute Epiglottitis* (caused by H. influenzae), which presents with high fever, drooling, and the "Thumb sign" on X-ray.

Q: Which of the following is NOT included in the criteria for very severe pneumonia in a child?

Fever. In pediatric respiratory medicine, the World Health Organization (WHO) and Integrated Management of Neonatal and Childhood Illness (IMNCI) guidelines classify pneumonia based on clinical severity to guide treatment. **Explanation of the Correct Answer:** **Fever** is a common symptom of respiratory infections but is **not** a diagnostic criterion for classifying the severity of pneumonia. While fever indicates an underlying infection, its presence or absence does not determine whether a child requires outpatient management or intensive inpatient care. **Analysis of Incorrect Options:** * **No feeding (Inability to drink):** This is a "General Danger Sign." According to IMNCI, any child with a cough or cold who exhibits danger signs (inability to drink/breastfeed, lethargy, or persistent vomiting) is classified as having **Very Severe Pneumonia**. * **Chest indrawing:** This signifies significant respiratory distress where the lower chest wall moves inward during inspiration. In the updated WHO classification, chest indrawing is a hallmark of **Severe Pneumonia**. * **Stridor:** Stridor in a calm child indicates upper airway obstruction and is considered a "red flag" sign, placing the child in the **Very Severe** category. **High-Yield Clinical Pearls for NEET-PG:** * **WHO Classification (Simplified):** 1. **Pneumonia:** Fast breathing (Age-specific: <2m: ≥60; 2-12m: ≥50; 1-5y: ≥40 bpm). 2. **Severe Pneumonia:** Fast breathing + Chest indrawing OR any General Danger Sign (Inability to feed, lethargy, convulsions, stridor in a calm child, or central cyanosis). * **Treatment:** Pneumonia is treated with oral Amoxicillin; Severe Pneumonia requires IV Ampicillin and Gentamicin. * **Fast Breathing** is the most sensitive clinical sign for pneumonia in children.

Q: Increased sweat chloride is seen in all conditions except?

Obesity. The sweat chloride test is the gold standard for diagnosing Cystic Fibrosis (CF), but several non-CF conditions can cause false-positive elevations. **Explanation of the Correct Answer:** **Obesity (Option D)** is the correct answer because it is **not** associated with increased sweat chloride levels. In fact, there is no physiological mechanism linking excess adipose tissue to impaired chloride transport in the eccrine glands. **Explanation of Incorrect Options:** * **Ectodermal Dysplasia (Option A):** This genetic disorder affects the development of sweat glands. Structural abnormalities in these glands can lead to an inability to reabsorb chloride, resulting in elevated levels. * **Nephrogenic Diabetes Insipidus (Option B):** Chronic dehydration and electrolyte imbalances associated with NDI can lead to concentrated sweat and elevated chloride readings. * **Glucose-6-Phosphatase Deficiency (Option C):** Also known as Von Gierke Disease (GSD Type I). The exact mechanism is complex but involves metabolic derangements that interfere with normal ion transport in sweat ducts. **High-Yield Clinical Pearls for NEET-PG:** * **Thresholds:** Sweat chloride **>60 mmol/L** is diagnostic for CF; **40–59 mmol/L** is intermediate/borderline. * **Other False Positives:** Adrenal insufficiency (Addison’s), Hypothyroidism, Malnutrition (Anorexia), Mucopolysaccharidosis, and Fucosidosis. * **False Negatives:** Edema (hypoproteinemia) and technical errors (inadequate sweat collection). * **The "Gold Standard" Method:** Quantitative pilocarpine iontophoresis.

Q: An infant presents with fever and persistent cough. Physical examination and a chest X-ray suggest pneumonia. Which of the following is the most likely cause of this infection?

Respiratory syncytial virus. **Explanation:** **Why Respiratory Syncytial Virus (RSV) is the correct answer:** Respiratory Syncytial Virus (RSV) is the most common cause of lower respiratory tract infections (LRTIs), including both **bronchiolitis and pneumonia**, in infants and young children worldwide. In the pediatric age group, viruses are responsible for the majority of community-acquired pneumonia cases, and RSV consistently tops the list. It typically presents with fever, cough, tachypnea, and wheezing. On a chest X-ray, viral pneumonia often manifests as bilateral interstitial infiltrates or hyperinflation. **Analysis of Incorrect Options:** * **Rotavirus (A):** This is the leading cause of severe **gastroenteritis** (diarrhea and vomiting) in infants; it does not cause primary respiratory infections. * **Adenovirus (B):** While Adenovirus can cause severe necrotizing pneumonia and conjunctivitis, it is less frequent than RSV. It is more commonly associated with pharyngoconjunctival fever. * **Coxsackievirus (C):** This virus is primarily associated with **Herpangina** and **Hand-Foot-and-Mouth Disease** (Group A) or myocarditis and pleurodynia (Group B), rather than typical pneumonia. **High-Yield Clinical Pearls for NEET-PG:** * **Most common cause of Pneumonia in infants:** RSV (Viral), followed by *Streptococcus pneumoniae* (Bacterial). * **Most common cause of Bronchiolitis:** RSV. * **Diagnosis:** Rapid antigen detection tests or PCR from nasopharyngeal Swabs. * **Treatment:** Primarily supportive (oxygen, hydration). **Ribavirin** is the only antiviral approved but is rarely used. **Palivizumab** (monoclonal antibody) is used for prophylaxis in high-risk preterm infants. * **X-ray finding:** Viral pneumonia usually shows diffuse, patchy, interstitial patterns, whereas bacterial pneumonia often shows lobar consolidation.

Q: A child experiences nocturnal asthma attacks twice a week and daytime attacks three or more times per week. According to asthma severity classification guidelines, how would this condition be categorized?

Moderate persistent asthma. To classify asthma severity in pediatric patients, we evaluate two main domains: **Daytime symptoms** and **Nocturnal (nighttime) awakenings**. ### Why "Moderate Persistent" is Correct According to the GINA and NHLBI guidelines, **Moderate Persistent Asthma** is characterized by: * **Daytime symptoms:** Daily (or >2 times per week, but not throughout the entire day). * **Nighttime awakenings:** More than once a week (e.g., 2 times/week), but not nightly. In this case, the child has daytime attacks ≥3 times/week and nocturnal attacks 2 times/week, which fits the criteria for Moderate Persistent. ### Why Other Options are Incorrect * **Mild Intermittent:** Symptoms occur ≤2 days/week and nocturnal awakenings ≤2 times/month. This patient exceeds both. * **Mild Persistent:** Symptoms occur >2 days/week (but not daily) and nocturnal awakenings occur 3–4 times/month. This patient’s nocturnal frequency (8 times/month) is too high for this category. * **Severe Persistent:** Symptoms occur throughout the day and nocturnal awakenings occur often (7 times/week). This patient’s symptoms are not yet continuous. ### NEET-PG High-Yield Pearls * **Step-up Therapy:** Moderate persistent asthma typically requires **Step 3 treatment**: Low-dose ICS + LABA or Medium-dose ICS. * **Rule of Two:** If a patient uses a rescue inhaler (SABA) >2 days/week, has >2 nocturnal awakenings/month, or >2 refills/year, their asthma is not well-controlled and requires maintenance therapy. * **PFT Findings:** In Moderate Persistent asthma, the FEV1 is typically between 60% and 80% of predicted.

Question 1

A 2-month-old infant is brought to the pediatric clinic with a history of high-pitched inspiratory stridor that began shortly after birth. The mother notes that the sound is most noticeable when the baby is crying or feeding. Which of the following is true regarding the diagnosis?

Accepted Answer

Omega sign improves in the prone position

Answer

Thumb sign improves in the supine position

Answer

Steeple sign is characteristic

Answer

Cherry-red epiglottis sign is characteristic

Question 2

A patient is shown using a metered -dose inhaler as shown in the image. Which of the following statements about spacer use is correct?

Accepted Answer

Decreases drug wastage & reduces oropharyngeal deposition

Answer

Increases systemic absorption of the drug

Answer

Makes inhaler technique more complicated and less effective

Answer

Has no effect on drug delivery

Question 3

Which among the following channels is affected in CFTR gene mutation?

Accepted Answer

Chloride

Answer

Potassium

Answer

Sodium

Answer

Magnesium

Question 4

A patient develops acute respiratory distress, stridor, unilateral hyperinflation of the chest with decreased breath sounds on that side. What is the most likely cause?

Accepted Answer

Foreign body aspiration

Answer

Asthma

Answer

Aspiration pneumonia

Answer

Pleural effusion

Question 5

Pneumatocele is commonest in which of the following conditions?

Accepted Answer

Staphylococcal pneumonia

Answer

Pneumococcal pneumonia

Answer

H. influenzae pneumonia

Answer

Viral pneumonia

Question 6

A 1-year-old infant presents with biphasic stridor, barking cough, and difficulty in breathing for the past 3-4 days. The infant has a high-grade fever and an elevated leukocyte count. Which of the following statements regarding this clinical condition is not true?

Accepted Answer

Antibiotics are the mainstay of treatment.

Answer

It is more common in boys than in girls.

Answer

The subglottic area is the common site of involvement.

Answer

Narrowing of the subglottic space with ballooning of the hypopharynx is seen.

Question 7

Which of the following is NOT included in the criteria for very severe pneumonia in a child?

Accepted Answer

Fever

Answer

No feeding

Answer

Chest indrawing

Answer

Stridor

Question 8

Increased sweat chloride is seen in all conditions except?

Accepted Answer

Obesity

Answer

Ectodermal dysplasia

Answer

Nephrogenic diabetes insipidus

Answer

Glucose 6 phosphatase deficiency

Question 9

An infant presents with fever and persistent cough. Physical examination and a chest X-ray suggest pneumonia. Which of the following is the most likely cause of this infection?

Accepted Answer

Respiratory syncytial virus

Answer

Rotavirus

Answer

Adenovirus

Answer

Coxsackievirus

Question 10

A child experiences nocturnal asthma attacks twice a week and daytime attacks three or more times per week. According to asthma severity classification guidelines, how would this condition be categorized?

Accepted Answer

Moderate persistent asthma

Answer

Severe persistent asthma

Answer

Mild intermittent asthma

Answer

Mild persistent asthma

Respiratory Diseases — MCQs

Respiratory Diseases — MCQs

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