Lung Abscess

Question 1

What is a lung abscess

Answer 1

Necrosis of the pulmonary parenchyma
caused by infection

Question 2

Main 2 causes of Lung abscess

Answer 2

Primary
Secondary

Question 3

Primary causes of lung abscess

Answer 3

• Prone to aspiration
  o Unconscious patient, general
  anaesthesia
  o Alcoholism, drug abuse
  o Epilepsy
  o Periodontal disease
• Complication of pneumonia
• Tricuspid valve endocarditis

Question 4

Secondary causes of lung abscess

Answer 4

Underlying lung disease
* Bronchiectasis
* Bronchial obstruction
* Immunodeficiency

Question 5

Main organisms causing lung abscess

Answer 5

Mainly anerobes
other - * Streptococcus milleri
* Streptococcus pyogenes
* Klebsiella
* Gram negative bacteria
* Staphylococcal (R/Heart endocarditis)

Question 6

Typical Hx of a lung abscess

Answer 6

• Indolent fever
• Cough - purulent sputum
• Haemoptysis
• Weight loss
• night sweats

Question 7

examination findings of lung abscess

Answer 7

• Anaemia
• Clubbing
• Crepitations on auscultation
• Pleural effusion

Question 8

Ix in lung abscess

Answer 8

Main - CXR, CT
Other- o ESR, FBC
o Sputum gram stain
o Sputum & blood culture
o Sputum DS for AFB
o Brochoscopy

Question 9

CXR findings in lung abscess

Answer 9

air- fluid level

Question 10

Dx consideration of an abscess in a dependant part

Answer 10

aspiration

Question 11

Dx consideration of multiple abscess

Answer 11

R/ heart endocarditis

Question 12

Dx consideration of multiple thin wall abscesses

Answer 12

staphylococcal infections

Question 13

Dx considerations of putrid sputum

Answer 13

anaerobes

Question 14

Rx of lung abscess

Answer 14

• Does not need drainage
• Antibiotics
  o Polymicrobial
  o Should cover anaerobes
  (Metronidazole + penicillin,
  clindamycin/meropenem)
  o At least for 3 weeks
• Physiotherapy

Question 15

Why is ABx usually not given for abscess patients

Answer 15

coz the ABx cannot penetrate the abscess wall but lung abscess is an exception. coz ABx can penetrate