Bronchitis Flashcards
Classifications of bronchitis
Acute bronchitis
Chronic bronchitis
Acute Bronchitis
Characteristics:
* Swelling of the lining of the trachea and bronchial tree.
* Narrowing of the tubes.
* Increased secretion of inflammatory fluid.
Common Features:
* Occurs following viral (commonly) or bacterial infection.
* Can result from chemical irritation (e.g., cigarette smoking, air pollution, or gastric acid reflux).
* Common in individuals of all ages.
* More prevalent in winter and/or areas with increased irritants
Chronic Bronchitis
Definition:
* Daily production of sputum for at least 3 months in 2 consecutive years.
Characteristics:
* Persistent inflammation of the bronchial passages.
* Prolonged and recurring symptoms.
* Often associated with long-term exposure to irritants.
Viral Agents Associated with Acute Bronchitis
- Influenza A and B.
- Respiratory syncytial virus (RSV).
- Parainfluenza.
- Adenovirus.
- Cold viruses (Rhinovirus & Coronavirus)
Bacterial Pathogens in Acute Bronchitis
- Streptococcus pneumoniae.
- Moraxella catarrhalis.
- Haemophilus influenzae.
- Chlamydia pneumoniae.
- Mycoplasma pneumoniae
Etiology and Pathophysiology
- Viral infection of trachea and bronchi leads to mucosal inflammatory response.
- Increased bronchial secretions result in acute bronchitis.
- Destruction of respiratory mucosa is part of the process
- Dysfunction impairs clearance and contributes to chronic airway diseases
- Recurrent or repeated acute respiratory infections
Pathophysiology in children
- Acute airway injury or continuous exposure to environmental agents, allergens, or irritants can lead to bronchospasm and cough.
- Recurrent aspiration or repeated viral infection increases the risk of chronic infections and lower respiratory tract infections.
- Children Predisposed to Aspiration:
If protective airway mechanisms are compromised, children may be infected with oral anaerobic strains of streptococci due to oropharyngeal aspiration.
- Tracheostomies in Children:
Often colonized with flora like α-hemolytic and γ-hemolytic streptococci.
Acute exacerbations may involve pathogens like Pseudomonas aeruginosa and Staphylococcus aureus (including methicillin-resistant strains)
Common Organisms in Children
- Streptococcus pneumoniae.
- Haemophilus influenzae.
- Mycoplasma pneumoniae.
- Moraxella catarrhalis- More prevalent in children aged 6-18 years and preschoolers (age < 5 years)
Mucociliary System in Acute Bronchitis
- Mucociliary clearance is the primary defense mechanism.
- Dysfunction impairs clearance and contributes to chronic airway diseases
Components of mucociliary system
- Cilia
- protective mucus layer
- airway surface liquid (ASL) layer.
ASL Dehydration and Chronic Inflammation
- ASL dehydration reduces mucus clearance.
- Contributes to mucous obstruction, goblet cell hyperplasia, and chronic inflammatory cell infiltration
Clinical presentation of acute bronchitis
- Follows upper respiratory infection.
- Hallmark: Hacking cough.
- Nasopharyngeal complaints.
- Production of clear phlegm, yellow, or green sputum.
- Fever and N/V/D are rare but can occur
- Sore throat.
- Runny or stuffy nose.
- Headache.
- Muscle aches.
- General malaise/fatigue.
- Chest pain (severe cases).
- Dyspnea and cyanosis, especially in patients with COPD
Complications of bronchitis
- Bacterial superinfection
- Chronic Bronchitis
- Pneumoniae
- Hemoptysis
Differential Diagnoses
- Asthma
- Influenza
- Bronchiolitis
- Chronic bronchitis (COPD)
Bronchiectasis - Acute or chronic sinusitis
- Bacterial tracheitis/
pharyngitis - Tonsillitis
Tests and investigations
- Full blood count
- Sputum cytology
- Chest radiography
- Bronchoscopy
- Spirometry
- Blood culture
- Troat swab
- Respiratory secretion cultures
- Procalcitonin
Procalcitonin
- Levels increase in bacterial infections (not in viral or other inflammatory conditions).
- Values ≥ 0.25 mcg/L (in non-ICU patients) or > 0.5 mcg/L (in ICU patients).
Clinical Use:
- Indicative for initiation of antibiotic therapy
- A decrease of at least 80% in levels can be a guide for discontinuing antibiotics.
Antibiotic Usage and Complications:
- The use of a procalcitonin algorithm may reduce antibiotic usage without increasing the risk of complications
Goals of Management
- Alleviate symptoms of acute bronchitis.
- Correct dehydration.
- Treat associated respiratory symptoms.
- Maintain and open obstructed bronchial airways.
- Thin obstructive mucus to facilitate expectoration.
- Prevent the development of complications
Symptomatic and Supportive care (Non-pharmacological)
- Ensure adequate oxygenation.
- Increase fluid intake to prevent dehydration.
- Decrease viscosity of respiratory secretions.
- Bed rest to relieve lethargy and malaise.
- Reassurance.
- Avoidance of environmental irritants, especially cigarette smoke.
Medications for management of Acute bronchitis
- Analgesics and antipyretics (e.g., paracetamol, aspirin, ibuprofen) to alleviate symptoms.
- Inhaled bronchodilators (e.g., salbutamol, terbutaline) for bronchial relaxation.
- 90-180 mcg (1-2 puffs) inhaled PO q4-6 hours.
- Inhaled corticosteroids (e.g., beclomethasone, fluticasone, budesonide inhaler).
- Oral corticosteroids (e.g., prednisolone) for a short course.
- Dextromethorphan for mild persistent cough.
- Codeine intermittently for severe cough
Antibiotic Therapy
- Routine antibiotic use discouraged.
- Consider if there is a suboptimal response to supportive intervention or persistent respiratory symptoms with fever.
- Directed toward respiratory pathogens (e.g., Strep. pneumoniae, H. influenzae, M. pneumoniae).
- Examples of antibiotics: Macrolides, fluoroquinolones, or beta-lactamase-resistant antimicrobials.
Evaluation of Therapy in Acute Bronchitis
- Amelioration of symptoms.
- Assess to rule out pneumonia and other complications.
- Treat any complications that arise.
- Assess the need for antibiotics based on clinical response.
- Ensure adherence to prescribed medications.
- Reassure the patient about the natural course of the disease.
- Encourage avoiding unnecessary antibiotic use