50 DISEASES DUE TO PROTOZOA 



AMCEBIC ABSCESS. 

 HISTORY. 



21 per cent, of dysenteric autopsies in various tropical countries had 

 liver abscess. 



35 per cent, of European soldiers in India who died from dysentery 

 had liver abscess. 



84*4 per cent, of the patients at the Seamen's Hospital who had 

 liver abscess revealed at the post-mortem evidence of dysentery. 



Liver abscess is more common in Europeans than natives and in 

 males than females. 



Waring savs that 65 per cent, of liver abscess cases were alcoholics. 



The disease is more common between the ages of 20 and 40, but 

 may occur at any age. 



In 90 per cent, of cases the organism is associated with or derived 

 from dysenteric processes in the colon. 



Liver abscess was operated upon in the days of Hippocrates. 



PATHOLOGY. 



The abscess, which is usually single, is most frequently in the right 

 lobe of the liver. It is so frequently in the right lobe because the 

 patient is in bed, and the right lobe being heavier than the left lies 

 lower, and the amoebas coming along the portal vein are assisted by 

 gravity to affect the lower or right lobe. No' matter how large the 

 abscess may be it never crosses over to the other side, and in this it 

 simulates hydatids and malignant growths. 



There is no anastamosis or communication whatever between the 

 vessels (jf the two sides; injection has proved this. There are really 

 two livers arising from two distinct buds from the gut and the gall- 

 bladder lies between them (Cantlie). 



An abscess may occupy half the liver, and the patient recover 

 because the other half takes on the work, as in the case when one 

 kidney is removed. There is no doubt that the whole liver is enlarged 

 and congested. The right lower lobe of the lung is congested. 



The abscess wall is thick, firm, ragged, and is made up of three 

 layers : — 



(i) The outer layer is of hyper^emic liver tissue with some con- 

 nective tissue. In some cases a fibrous capsule may be formed from it. 



(2) The middle layer is of brownish red friable liver tissue. 



(3) The inner layer consists of grey necrosed tissue containing 

 amoebae and pus cells, the latter less frequently. There is no lining 

 membrane. 



The contents of the abscess consist of a viscid chocolate-coloured 



