Differential Diagnoses

Differential Diagnosis I: Pneumonia 

 Pathophysiology

  • Aspiration of secretions is the most common route;
    • Can cause of a lower respiratory infection. 
  • Additional route of contamination: inhalation of a microorganism released by another person through coughing or sneezing.
  • Endotracheal tubes can have a biofilm of bacteria acquired through suctioning. 
  • It is the 8th leading cause of death in the United States (McCance & Huether, 2019).

Clinical manifestations (resembling asthma)

  • Dyspnea
  • Coughing
  • Chest pain
  • Fever
  • Productive or nonproductive cough
  • Treatment: correcting ventilation and oxygenation first (McCance & Huether, 2019).

Rationale

  • Pneumonia is caused by a bacteria or aspiration, but asthma is not caused by either. 
  • It is treated through antibiotics, versus corticosteroids and bronchodilators. 
  • Pneumonia can lead to septic shock.  
  • Sputum culture tested negative for this patient case. 
  • Chest x-ray would show consolidation or infiltrates if the diagnosis was pneumonia. 
    • In this case the results showed bronchial thickening, hyperinflation, and focal atelectasis. 
    • Pulmonary function tests (PFT) are used to diagnose asthma when patient is not in severe distress.
  • Pneumonia is an infection of the lower respiratory tract due to bacteria, viruses, protozoa, fungi, or parasites.
  • Risk Factors 
    • Weak or compromised immune system. 
    • Already diagnosed underlying lung disease such as COPD, difficulty swallowing, immobilized, or being intubated.
  • Most cases are followed by a severe viral respiratory tract infection. 
  • Can be acquired in many ways; community, hospital, ventilator associated, and healthcare associated (McCance & Huether, 2019).

Diagnosis II: Croup (Acute Laryngotracheobronchitis)

Figure 2. Edema in croup caused by narrowing and obstruction (McCance & Huether, 2019)

Pathophysiology

  • Inflammation from vocal cords to the bronchioles from Influenza A or a respiratory syncytial virus
  • Westley Score= tool most often used to estimate the severity of croup which assesses:
    • Stridor
    • Retractions
    • Air entry
    • Cyanosis
    • Dyspnea
    • Level of consciousness (LOC) (McCance & Huether, 2019).

Clinical Manifestations (resembling asthma)

  • Dyspnea 
  • Retractions
  • Low grade fever
    • This can occur with asthma when asthma is triggered from a virus
  • Coughing
  • No treatment for mild symptoms
  • Treatments for moderate-severe include injected steroids and inhaled glucocorticoids  (McCance & Huether, 2019).

Rationale

  • Conjunctivitis and nasal discharge from a respiratory virus. 
  • If patient was diagnosed with croup their neck x-ray would show a steeple sign for patients with moderate-severe symptoms. 
    • In asthma, typically no neck x-ray is ordered.
  • Treatments for moderate-severe croup that are not used in asthma: 
    • Nebulizer racemic epinephrine stimulates alpha and beta adrenergic receptors 
      • To alleviate edema in mucosa 
    • Oxygen administration
      • Not generally administered in asthma except in severe asthma exacerbation. 
  • Onset is usually caused by a virus or result of foreign body obstruction in the upper airway.
  • Stridor = a harsh, barky cough heard when there is a tracheal foreign body obstruction.
    • This is a classic symptom of an irritation in the upper airway
    • In asthma, stridor is not heard.
      • Generally, wheezing in the lower airways is present.
  •  Risk of croup: 
    • More frequently seen in younger children (6 months – 3 years old); 
      • Asthma cannot typically be diagnosed until 2 years old.
      • Due to the smaller luminar openings and easily collapsible diameter;
        • Decreased airway opening makes you prone to frequent upper airway obstructions (McCance & Huether, 2019).

Differential Diagnosis III: Bronchiolitis

Figure 1. Pediatric Bronchiolitis Bronchial Tubes (Cleveland Clinic, 2015)

Pathophysiology

  • V/Q Mismatch
  • Bronchospasm 
  • Hypoxemia
  • Air Trapping
  • Increased functional residual capacity
  • Decreased Lung Compliance (Cordell, 2019). 

Clinical Manifestations (resembling asthma)

  • Rapid respiratory rate
  • Significant use of accessory muscles
  • Dry, nonproductive cough
  • Hyperinflated chest
  • Wheezing upon auscultation of the chest (Cordell, 2019) 

Rationale

  • Low grade fever
    • This can occur with asthma when asthma is triggered from a virus
  • Rhinorrhea
    • This can occur with asthma when asthma is triggered from a virus
  • Decreased appetite 
  • Pulsus Paradoxus (Cordell, 2019). 
  • A respiratory tract infection of the small airways and bronchioles
  • Developed by a virus, which causes diffuse inflammation
  • Occurs mainly in infants and young toddlers.
  • Can lead to an increased risk for asthma later in childhood
    • Particularly affects those with a family history of asthma (McCance & Huether, 2019).