Lower Respiratory Tract Infections in Adults Flashcards
What are the clinical features of acute bronchitis?
Cough (productive or dry), often lasting for several weeks.
Mild fever, wheezing, chest tightness.
Sore throat, fatigue, and malaise.
Rhonchi or rales heard on auscultation.
Common Cause: Primarily viral (e.g., rhinovirus, influenza, parainfluenza), but can be bacterial (e.g., Mycoplasma pneumoniae).
What are the clinical features of pneumonia?
Fever, chills, productive cough (with purulent or blood-tinged sputum), dyspnea.
Pleuritic chest pain, tachypnea, hypoxia, and tachycardia.
Crackles or dullness on percussion, and increased tactile fremitus.
Common causes include Streptococcus pneumoniae, Haemophilus influenzae, and Staphylococcus aureus.
What are the clinical features of bronchiectasis, lung abscess, and empyema?
Bronchiectasis:
Chronic productive cough, purulent sputum, recurrent respiratory infections.
Hemoptysis, dyspnea, wheezing, and fatigue.
Lung Abscess:
Fever, cough (often with foul-smelling sputum), pleuritic chest pain, weight loss, night sweats.
Empyema:
Fever, pleuritic chest pain, dyspnea, and decreased breath sounds over the affected area.
Associated with pus in pleural space (visible on imaging).
What is the pathogenesis of bronchopneumonia and lobar pneumonia?
Bronchopneumonia:
Inflammation starts in the bronchioles and spreads to surrounding alveoli, typically affecting multiple lobes.
Often caused by Streptococcus pneumoniae, Haemophilus influenzae, or Staphylococcus aureus.
Lobar Pneumonia:
Involves consolidation of a whole lobe due to alveolar infection with exudate.
Usually caused by Streptococcus pneumoniae.
Both types can lead to respiratory failure, pleuritis, and sepsis in severe cases.
What are the common bacterial and viral organisms causing lower respiratory tract infections?
Bacterial Causes:
Streptococcus pneumoniae, Haemophilus influenzae, Mycoplasma pneumoniae, Chlamydia pneumoniae, Klebsiella pneumoniae, Staphylococcus aureus (including MRSA).
Viral Causes:
Influenza virus, respiratory syncytial virus (RSV), parainfluenza, adenovirus, coronavirus.
What are the potential causes of recurrent pneumonia?
Underlying chronic lung disease (e.g., COPD, bronchiectasis).
Aspiration pneumonia due to swallowing dysfunction or gastroesophageal reflux.
Immunocompromised states (e.g., HIV/AIDS, chemotherapy, organ transplants).
Structural abnormalities in the lungs (e.g., bronchiectasis, foreign body aspiration).
Infectious organisms resistant to standard treatments (e.g., Staphylococcus aureus, including MRSA).
How does hospital-acquired pneumonia (HAP) differ from community-acquired pneumonia (CAP)?
Community-Acquired Pneumonia (CAP):
Acquired outside of a healthcare setting.
Common pathogens include Streptococcus pneumoniae, Haemophilus influenzae, Mycoplasma pneumoniae.
Hospital-Acquired Pneumonia (HAP):
Acquired after 48 hours of hospital admission, typically more resistant organisms.
Common pathogens include Pseudomonas aeruginosa, MRSA, Acinetobacter, and Enterobacter species.
What is the clinical management of pneumonia?
Antibiotics: Tailored based on suspected organisms (e.g., amoxicillin for Streptococcus pneumoniae, macrolides or doxycycline for Mycoplasma pneumoniae).
Supportive therapy:
Oxygen therapy for hypoxia.
Hydration to support respiratory function.
Pain management (e.g., paracetamol for chest pain/fever).
Cough suppressants (if necessary) or expectorants.
Hospitalization: For severe cases, particularly in elderly or immunocompromised patients.
What is the role of supportive therapy in managing lower respiratory infections?
Oxygen supplementation for hypoxia.
Hydration to thin mucus and support respiratory function.
Pain management: Paracetamol or NSAIDs for fever and chest pain.
Ventilatory support: In severe cases, mechanical ventilation may be necessary.
Rest: Important for recovery and immune function.
What is the general management approach for bronchiectasis, lung abscess, and empyema?
Bronchiectasis:
Airway clearance techniques, such as chest physiotherapy.
Antibiotics for exacerbations (e.g., fluoroquinolones, macrolides).
Immunization to prevent infections.
Lung Abscess:
Antibiotics (e.g., clindamycin, penicillin with beta-lactamase inhibitors).
Drainage may be needed in severe cases.
Empyema:
Antibiotics tailored to culture results.
Chest tube drainage or thoracentesis for fluid removal.
How do the approaches to managing respiratory infections differ between primary care and secondary care?
Primary Care:
Focuses on early diagnosis and outpatient treatment for conditions like acute bronchitis and mild pneumonia.
Use of empiric antibiotics based on clinical presentation.
Management of chronic respiratory conditions (e.g., COPD, asthma).
Secondary Care:
Involves hospitalization for severe infections or complicated pneumonia.
Intensive monitoring, IV antibiotics, and advanced diagnostic imaging.
Management of rare or severe lung infections (e.g., lung abscess, empyema).
