This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: None, Subject name: Surgery
Most common cause of amoebic lung abscess is ? 
Select and explain. 
A. Direct extension from liver, B. Hematogenous spread, C. Lymphatic spread, D. By inhalation
A: Direct extension from liver
Answer: A: Direct extension from liver 
Explanation: Ans. is 'a' i.e., Direct extension from liver Amoebic lung abscess is a result of direct spread of infection from liver to lung. The infection spreads directly through the diaphragm. The most common area of the lung involved is right lower lobe. The amoebic liver abscess ruptures and then it can involve any of the following structures. i) Right lung (Most commonly) iv) Left pleural cavity ii) Right pleural cavity v) Pericardium iii) Left lung iv) Peritoneal cavity Also know "Pleuropulmonary involvement is seen in 20-30 % of cases and is the most frequent complication of Amoebic liver abscess"- Harrison