2. CASE PRESENTATION
HISTORY
A 35 years old male patient
2 mo history of Productive Cough (copious purulent sputum with no hemoptysis),
Right sided chest pain( in 4th ICS, gradually increased in intensity, aggravated with
deep breathing and coughing, relieved with pain killers, radiating to the back and
ipsilateral shoulder)
Fever (low grade, continuous with rigors and chills)
Shortness of breath( MMRC Grade 2, gradually progressive, exertional, no
orthopnea, PND)
Nausea and vomiting
3. HISTORY
Scrap picker by profession
No History of travel abroad
No history of IV drug abuse
No History of leg swelling
No significant drug history
No past history of HTN, DM, Hep B, Hep C, TB, asthma or any other respiratory
illness
4. EXAMINATION
BP 110/80 Pulse 112/min SaO2 94 % RA, RR 20/min Temp 100 F
GPE
Anemic, Clubbed,
CVS - S1 + S2 no added sounds or murmurs
Resp - R sided decreased breath sounds with inspiratory crackles on auscultation
GIT - Not significant
CNS - Not significant
5. LABORATORY
Hb 11g/dl TLC 22.2 Pt 415 CRP 285
Sputum AFB/ Xpert MTB Neg - 2 months back ( Started on ATT for 2 months
without evidence)
Sputum bacterial C/S Neg
Urine RE Normal
Urea 40 Cr 1.0 RBS 85 HbA1C 5.03 LFT normal
HBsAg /Anti HCV/Anti HIV Neg
11. PATHOPHYSIOLOGY
The bacterial inoculum reaches the lung parenchyma, often in a dependent lung
area.
Pneumonitis, followed by necrosis, occurs over 7– 14 days.
Cavitation occurs when parenchymal necrosis leads to communication
with the bronchus
entry of air and expectoration of necrotic material leading to the
formation of an air-fluid level.
Bronchial obstruction leads to atelectasis with stasis and subsequent
infection, which can predispose to abscess formation.
16. MICROBIOLOGY
Anaerobes (93%)
Fusobacterium nucleatum and
necrophorum
Bacteroides fragilis
Pigmented and non pigmented Prevotella
Peptococcus and peptostreptococcus
Aerobes
Streptococcus ‘milleri’ group
Staphylococcus aureus
Klebsiella spp
Pseudomonas aeruginosa
Streptococcus pyogenes
Haemophilus influenza
Nocardia
17. DIFFERENTIAL DIAGNOSIS
Cavitating carcinoma- Primary or metastatic
Cavitatory TB
GPA (Wegener’s)
Infected pulmonary cyst or bulla (can produce a fluid level, usually thinner-walled)
Aspergilloma
Pulmonary infarct
Rheumatoid nodule
Sarcoidosis
Bronchiectasis.
18. INVESTIGATIONS
MICROBIOLOGICAL CULTURES
Blood cultures
Sputum or bronchoscopic specimen (BAL or brushings rarely needed)
Transthoracic percutaneous needle aspiration (CT- or US-guided)
(Risk of bleeding, pneumothorax, and seeding of infection to pleural space,
if abscess not adjacent to the pleura)
19. IMAGING STUDIES
Useful to exclude aspirated foreign body, underlying neoplasm, or bronchial
stenosis and obstruction
These include CXR and CT scan chest
20. CHEST X RAY
consolidation
cavitation
air-fluid level (if the patient is unwell, the CXR is likely to be taken in a semi-
recumbent position, so an air-fluid level may not be visible).
50% of abscesses are in the posterior segment of the right upper lobe or the apical
segments of either lower lobe
23. COMPUTED TOMOGRAPHY
CHEST( CT Chest)
if the diagnosis is in doubt and cannot be confirmed from the CXR appearance
if the clinical response to treatment is inadequate
to define the exact position of the abscess (which may be useful for physiotherapy
or if surgery is being considered—rarely needed)
can determine the presence of obstructing endobronchial disease eg due to
malignancy or foreign body,
useful in defining the extent of disease in a very sick patient who has had
significant haemoptysis.
25. CT Chest
LUNG ABSCESS vs EMPYEMA THORACIS
• Lung abscess appears as a
rounded intrapulmonary mass
• no compression of adjacent lung
• with a thickened irregular wall
• making an acute angle at its
contact with the chest wall.
26. EMPYEMA THORACIS
empyema typically has a
lenticular shape
compresses adjacent lung
creates an obtuse angle as it
follows the contour of the
chest wall.
27. MANAGEMENT
ANTIBIOTICS
to cover aerobic and anaerobic infection including β-lactam/ β-lactamase
inhibitors, e.g. co-amoxiclav and clindamycin.
Long courses are needed
Risk of Clostridium difficile diarrhea
Infections are usually mixed, therefore antibiotics to cover these
Metronidazole to cover anaerobes
Common practice would be 1 – 2 weeks IV treatment with a further 2–6 weeks oral
antibiotics, often until outpatient clinic review.
28. DRAINAGE
Spontaneous drainage is common with the production of purulent sputum
increased with postural drainage and physiotherapy
No data to support use of bronchoscopic drainage
Percutaneous drainage with radiologically placed small percutaneous drains for
peripheral abscesses may be useful in those failing to respond to antibiotic and
supportive treatment
usually placed under US guidance
29. SURGERY
Surgery is rarely required if appropriate antibiotic treatment is given
It is usually reserved for complicated infections failing to respond to standard
treatment after at least 6 weeks of treatment
May be needed if
a. Very large abscess (>6cm diameter)
b. Resistant organisms
c. Haemorrhage
d. Recurrent disease
Lobectomy or pneumonectomy is occasionally needed if severe infection with an
abscess leaves a large volume of damaged lung that is hard to sterilize.
30. FAILED RESPONSE TO TREATMENT
If slow to respond, consider
1. Underlying malignancy
2. Unusual microbiology, e.g. mycobacterium, fungi
3. Immunosuppression
4. Large cavity (>6cm)
5. Non-bacterial cause, e.g. cavitating malignancy, GPA (Wegener’s)
6. Other cause of persistent fever, e.g. Clostridium difficile diarrhoea, antibiotic-
associated fever.
31. PROGNOSIS
85% cure rate in the absence of underlying disease.
Mortality is reported as high as 75% in immunocompromised patients.
Poor prognostic factors
• presence of underlying lung disease
• increasing age
• large abscesses (>6cm)
• Staphylococcus aureus infection
• Immunocompromised patients
32. REFERENCES
Oxford Handbook of Respiratory Medicine Third edition
Clinical respiratory medicine Fourth edition
Fishman's Pulmonary Diseases and Disorders Fifth edition
34. QUESTION 1
All of the following are risk factors of lung abscess except
a) Hemorrhagic stroke
b) Seizure disorders
c) Local anesthesia
d) Poor dentition
e) Chronic kidney disease
f) Alcoholism
35. QUESTION 2
Causes of cavitory lung disease include which of the following
a. Pulmonary embolism
b. Sarcoidosis
c. Adenocarcinoma lung
d. Rheumatoid arthritis
e. Eosinophilic pneumonia
f. Pneumoconiosis
g. Friedlanders pneumonia
h. MAC
i. Cryptogenic fibrosing alveolitis
36. QUESTION 3
All of the following organisms can cause cavitating pneumonia except
a. Entemoeba histolytica
b. Pseudomonas aeruginosa
c. Nocardia asteroids
d. Mycoplasma pneumonia
e. Staph aureus
f. Aspergillus spp
37. QUESTION 4
A 70 yrs old male patient known case of COPD presented to us with Shortness of
breath, Productive cough, High grade fever with rigors and chills and chest
heaviness for 1 month. The patient had a history of 30 years of water pipe use
(Chilam). OE BP 130/90 Pulse 112 SaO2 90% RA and Temp 101 F.
A CXR was done.
39. What is your diagnosis
How will you classify the disease
What will be your diagnostic approach in this patient
How will you manage this patient