Lung Abscess - Long Case With Questions & Answers

Chief complaints:

• Cough with profuse foul smelling sputum for … days
• Hemoptysis for … days
• Fever for … days
• Chest pain for … days
• Malaise, weakness, loss of weight for … days.

History of present illness: According to the statement of the patient, he was reasonably well … days
back. Since then, he has been suffering from severe cough with production of copious foul smelling
purulent sputum. It is occasionally associated with scanty amount of blood. He also complains of
high grade continuous fever, highest recorded 104°F. The fever is associated with chills and rigors
and profuse sweating, subsides only with paracetamol. The patient also complains of right sided chest
pain, which is compressive in nature, worse with inspiration and during coughing, but there is no
radiation. For the last ... days, he is also suffering from malaise, weakness, anorexia and loss of
approximately 15 kg of body weight. His bowel and bladder habits are normal.

History of past illness: He was suffering from pneumonia 6 months back from which there is complete recovery.

Family history: Nothing significant.
Personal history: He smokes about 25 sticks a day for 25 years. He is also an alcoholic.
Socioeconomic history: He is a day laborer and lives in a slum area with poor sanitation.
Drug history: The patient was treated by local physicians with antibiotics, cough syrup and
paracetamol, but no improvement.

General Examination
The patient looks toxic and emaciated
Generalized clubbing is present in all the fingers and toes
Moderately anemic
No jaundice, cyanosis, koilonychia, leukonychia or edema
No thyromegaly or lymphadenopathy

Vitals:
Pulse: 110/min
BP: 110/75 mm Hg
Temperature: 103º F
Respiratory rate: 28/min.

Systemic Examination
Respiratory System: (Supposing right sided)
Inspection:

• Movement is restricted in the right side of the chest.

Palpation:

• Trachea is central in position
• Apex beat is in the left 5th intercostal space in the midclavicular line
• Vocal fremitus is increased on the right side of the chest
• Chest expansion is reduced on the right side.

Percussion:

• Percussion note is woody dull over right side of chest from … to … intercostal space
• Upper border of the liver dullness is in the right 5th intercostal space in midclavicular line
• Cardiac dullness is normal.

Auscultation:

• Breath sound is bronchial in … intercostal space on the right side. In other places, it is vesicular.
• Vocal resonance is increased over the same area
• There are coarse crepitations over the right side of the chest in … intercostal space, reduces on coughing.

Examination of the other systems reveals no abnormalities.

Provisional diagnosis: Right sided Lung Abscess.

Questions Likely To Be Asked By The Examiner: 

Q. What are the differential diagnoses?
A. As follows:

• Consolidation (during resolution stage)
• Bronchiectasis
• Bronchial carcinoma
• Pulmonary TB.

Q. Why lung abscess and not consolidation?
A. Because:

• The patient is toxic with high temperature. There is cough with foul smelling purulent sputum.
• Clubbing is present (it is usually present in 10% cases after 3 weeks.)
• To be confirmed—chest X-ray should be done (which shows cavity with air fluid level).

Q. With these findings, can it be consolidation only?

A. Yes, it may be during resolution stage.

Q. Could it be bronchiectasis?
A. Yes, because there is clubbing with coarse crepitations. However, in bronchiectasis, crepitations
are mostly on the basal area. Also, there is no fever and patient is not toxic in bronchiectasis (until
there is secondary infection).
Also, in the history of bronchiectasis, there is profuse expectoration of sputum after waking up
from sleep in the morning.

Q. What investigations should be done in lung abscess?
A. As follows:

• CBC (leukocytosis)
• X-ray chest (cavity with air fluid level)
• Sputum examination—Gram staining, C/S (both aerobic and anaerobic), AFB, fungus, malignant cells
• Bronchoscopy (to exclude mass and foreign body)
• CT or MRI (in some cases)
• Blood sugar

Q. What is lung abscess? What are the causes?

A. It is a localized area of suppuration within the lung parenchyma that leads to parenchymal

destruction and is manifested radiologically as a cavity with air fluid level.

Causes of lung abscess:

• Aspiration of nasopharyngeal or oropharyngeal contents, such as in vomiting, anesthesia, tooth extraction, tonsillectomy, unconscious patient, alcoholism and achalasia of cardia. Organisms are aerobic and anaerobic.
• Specific infections (Streptococcus pneumoniae type 3, Staphylococcus aureus, Klebsiella pneumoniae and fungal). In HIV, Pneumocystis jiroveci, Cryptococcus neoformans and Rhodococcus equi.
• Obstruction by bronchial carcinoma, adenoma and foreign body.
• Infection in pulmonary infarction (by Streptococcus pneumoniae, Staphylococcus aureus, Haemophilus influenzae and anaerobic).
• Spread from liver abscess and subphrenic abscess (due to transdiaphragmatic spread).
• Hematogenous from other infection as septic emboli (pelvic abscess and salpingitis, right sided endocarditis, IV drug abuse).

Q. How the patient of lung abscess usually presents?

A. As follows

• Severe cough with profuse foul smelling sputum, may be fetid (anaerobic)
• Hemoptysis
• Chest pain (pleuritic)
• Fever, usually high with chill and rigor, with profuse sweating
• Malaise, weakness and loss of weight.

Q. What are the physical findings in lung abscess?

A. It depends on site. If deep seated within the lung parenchyma, there may not be any physical

findings. If it is near the surface, findings are:

• Features of consolidation, usually
• Rarely, features of cavitation
• Sometimes, combined features of consolidation and cavitation, if large abscess.

Q. What is the common site of lung abscess?

A. As follows:

1. Lung abscess is common in right middle lobe.

2. If it is due to aspiration, then the commonest site depends on the posture of the patient during

aspiration.

 - If the patient is lying down, abscess forms in the posterior segment of upper lobe or superior

segment of lower lobe

 - If the patient is in upright position, the common site is basal segment.

Q. Why lung abscess is more common on the right side?

A. Lung abscess is more common in right side due to less obliquity of the right major bronchus.

Q. What are the complications of lung abscess?

A. As follows:

• Pleurisy
• Empyema
• Bronchiectasis
• Fibrosis
• Septicemia
• Cerebral abscess (common in parietal lobe or posterior frontal region)
• Amyloidosis (rare), in chronic cases.

Q. What are the other causes of cavitary lesion in lung?

A. As follows:

• Tuberculosis
• Cavitating bronchial carcinoma
• Pulmonary infarction
• Fungal infection (histoplasmosis)
• Wegener’s granulomatosis
• Rheumatoid nodules
• Consolidation (Streptococcus pneumoniae serotypes 3).

Q. How to treat lung abscess?

A. Sputum is sent for C/S and broad-spectrum antibiotic should be started.

• Broad-spectrum antibiotic—amoxicillin or co-amoxiclav or erythromycin plus metronidazole. Or, cefuroxime 1 g IV 6 hourly plus metronidazole 500 mg IV 8 hourly for 5 days, followed by cefaclor plus metronidazole (in 70% cases anaerobic organisms are present, but mixed organisms are also common).
• If improves, continue as above. If no response, antibiotic is given according to C/S. Treatment should be continued for 4 to 6 weeks.
• Postural drainage and chest physiotherapy.
• If no response to medical therapy (occurs in 1 to 10% cases), percutaneous aspiration (USG or CT guided).
• Sometimes, surgery (lobectomy) may be done.
• Treatment of the cause, if present.

Indications of surgery:

• No clinical response
• Increasing size of the abscess.
• Massive hemorrhage or hemoptysis.