Embedded Files
Infection of the lung parenchyma leading to inflammation and alveolar consolidation. Can be viral, bacterial, or atypical, with varying presentations depending on age and organism.
Infection of the lung parenchyma leading to inflammation and alveolar consolidation. Can be viral, bacterial, or atypical, with varying presentations depending on age and organism.
Risk Factors
Age <5 years or >65 years
Prematurity
Chronic lung disease (e.g. asthma, cystic fibrosis)
Congenital heart disease
Immunocompromise (e.g. HIV, chemotherapy, steroid use)
Neurological or swallowing disorders
Malnutrition
Environmental exposure – tobacco smoke, overcrowding, daycare attendance
Aetiology
Bacterial – Streptococcus pneumoniae (most common), Haemophilus influenzae, Moraxella catarrhalis
Atypical – Mycoplasma pneumoniae, Chlamydophila pneumoniae
Viral – RSV, influenza, adenovirus, parainfluenza, metapneumovirus
Neonates – Group B Streptococcus, E. coli, Listeria monocytogenes
Pathophysiology
Inhalation or aspiration of pathogen → infection of alveoli → local inflammation
Alveolar exudate and consolidation impair gas exchange
Systemic inflammatory response can lead to fever, malaise, and tachycardia
In severe cases, may lead to sepsis, pleural effusion, or empyema
Diagnosis
Clinical features include fever, cough, tachypnoea, increased WOB, decreased feeding or lethargy in infants
Crackles or decreased breath sounds on auscultation
Hypoxia (SpO₂ <92%), nasal flaring, grunting
CXR may show lobar consolidation, patchy infiltrates, or effusion – not always necessary
Viral pneumonias tend to present with wheeze and upper respiratory symptoms
Differential Diagnosis
Bronchiolitis
Asthma
Viral upper respiratory tract infection
Tuberculosis
Aspiration pneumonitis
Congestive heart failure
Investigations
Pulse oximetry
CXR – if severe, hospitalised, or unclear diagnosis
Full blood count, CRP – non-specific, sometimes used in hospital
Blood cultures if febrile or toxic
Nasopharyngeal swab PCR – especially in winter or in hospitalised children
Sputum culture – in older children or adults with productive cough
Consider pleural ultrasound or CT if effusion suspected
Management
Mild (outpatient)
Empiric oral antibiotics – amoxicillin first-line (S. pneumoniae cover)
Atypical cover (e.g. Mycoplasma) – add azithromycin or roxithromycin
Supportive care – fluids, antipyretics
Moderate to severe (inpatient)
IV antibiotics – benzylpenicillin or ceftriaxone ± azithromycin
Oxygen if SpO₂ <92%
Fluids – oral, NG, or IV
Chest physiotherapy generally not indicated
Treat complications (e.g. chest drain if empyema)
Complications
Pleural effusion or empyema
Lung abscess
Sepsis or bacteraemia
Necrotising pneumonia
Bronchiectasis (esp. after severe or recurrent pneumonia)
Respiratory failure
Death – especially in infants, elderly, or immunocompromised
Prognosis
Most children and adults recover fully with appropriate antibiotics
Viral pneumonia usually self-limiting
Complications more common in infants, comorbid children, or delayed presentation
Prevention includes immunisation (pneumococcal, Hib, influenza), hand hygiene, smoke-free environment
Page updated
Google Sites
Report abuse