LUNG ABSCESS
A lung abscess is a cavity within the substance of the lung filled with
necrotic tissue and pus which occurs as a result of infection.
Antibiotic management should be considered upon diagnosis while
awaiting confirmation of the causative organism by sputum culture.
CAUSES
· The aspiration of infected mucus or tissue from the nose, mouth or
pharynx especially in alcoholics, epileptics, unconscious or
anaesthetised patients and following dental procedures.
· Inadequately treated bacterial pneumonia (especially, gram negative
bacteria, Staphylococcus aureus, beta-haemolytic streptococci).
Staphylococcus aureus usually presents as multiple abscesses,
especially in children.
· Presence of a foreign body within the lung either by inhalation or
penetrative lung injury
· Obstruction of an airway by tumour
· Septic emboli from other infected areas of the body e.g. From
septicaemia and endocarditis
· Tuberculosis
SYMPTOMS
· High swinging fever
· Breathlessness
· Cough, productive of copious amounts of foul smelling sputum.
· Haemoptysis
· Chest pains on breathing if associated with inflammation of pleura
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DISORDERS OF THE RESPIRATORY SYSTEM
SIGNS
· Fever
· Tachycardia
· Tachypnoea
· Chest wall tenderness
· Dull percussion note
· Poor air entry
INVESTIGATIONS
· FBC
· Chest X-ray (may see air fluid level in area of consolidation)
· Sputum culture
· Sputum AFB`s
· Blood culture
TREATMENT
Treatment objectives
· To clear abscess collection
· To treat underlying cause
Non-pharmacological treatment
· Chest physiotherapy - postural drainage
· Improve nutritional status
Pharmacological treatment
(Evidence rating: A)
· Cloxacillin, IV,
Adults
500 mg 6 hourly for 14 days
Children
5-12 years; 250 mg 6 hourly for 14 days
1-5 years; 125 mg 6 hourly for 14 days
<1 year; 62.5 mg 6 hourly for 14 days
Plus
Gentamicin, IV,
Adults
40-80 mg 8 hourly for 14 days
Children
1-12 years; 2.5 mg/kg 8 hourly for 14 days
> 1 year; 2.5 mg/kg 12 hourly for 14 days
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DISORDERS OF THE RESPIRATORY SYSTEM
Plus
Metronidazole, IV,
Adults
500 mg 8 hourly for 14 days
Children
7.5 mg/kg 8 hourly for 14 days
Alternative treatment
· Clindamycin, oral,
Adults
150-300 mg 6 hourly for 14 days
Children
3-6 mg/kg 6 hourly for 14 days
REFER
Refer to a specialist or higher level facility if abscess is not resolving on
above treatment as surgery may be required to drain the abscess.
