Pathology: Inflammationof the lung parenchyma as a result of an infection. Community acquired (CAP) orhospital acquired (HAP) developing 48hrs after admission
Aetiology: Certaingroups are at increased risk of pneumonia: diabetics, COPD, previoussplenectomy, underlying cardiorespiratory disease, elderly and HIV patients.
Common Causes of CAP Common Causes of HAP
Streptococcus Pneumonia Gram Negative Bacteria
Haemophilus Influenza Staphylococcus Aureus
Mycoplasma Pneumonia Streptococcus Pneumonia
Symptoms: Pleuriticpain, productive cough, rigors and shortness of breath.
AtypicalPneumonias cause atypical symptoms.
Mycoplasma:Erythema multiforme (‘target lesions’), erythema nodosum and DIC. Legionella: Flu-like symptoms. Urinetested for antigen
Signs: Pyrexia,dyspnea, tachypnoea, confusion, cough with purulent sputum. Auscultation mayreveal crackles and bronchial breathing. A dull percussion note may be present
Investigations: Chest X-Ray: Consolidation andpotentially pleural effusions
Bloods: FBC, U&E, CRP and liver function tests,ABG, blood cultures.
Sputum culture and gram stain: Suspected cases of TB - Acid Fast Bacilli.
Urine antigen: Pneumococcal (moderate to highseverity), legionella (high severity)
Bronchoscopy: in persistent cases post course ofantibiotics
Treatment: Oxygen: Aim for oxygen saturations of94-98%
IV Fluids: Fluid balance should be assessed andsupplemented as required
IV/PO Antibiotics: Amoxicillin for non-severe, Tazocin for SeverePneumonia.
Legionella Pneumonia - Clarithromycin & Rifampicin
Complications: Septicaemia, para-pneumonic effusions, empyemaand cavity formation
Prognosis: Dependenton CURB-65 Score.
Postdischarge, patients should have a follow up Chest X-Ray at 6 weeks
Figure 2.1 Right lowerlobe pneumonia