The infection of Entamoeba is more common in children and young adults. The trophozoites.by their amoeboid movement and also by the proteolytic enzyme, penetrate through the mucosa and burrow deeper and deeper by lysis of the tissue up to the submucous coat. They rapidly multiply here and cause destruction of the surrounding tissues. This results in the formation of ulcers containing cellular debris, bacteria and blood corpuscles. Abscess may be formed. Sometimes the ulcers burst and the blood vessels are ruptured.
The blood, and the ulcer contents are discharged along with the stools, leading to a condition called as amoebic dysentery. The patient suffers from discomfort owing to the intense pain in the abdomen and often mucus is also discharged along with the stools. The stools are acidic and generally contain swarms of entamoebae.
E. histolytica causes amoebiasis which can be acute or chronic depending on the infection. Nausea, intestinal irregularity and fatiguability are the common symptoms of amoebiasis. At times the trophozoites through the blood circulation may enter liver, lungs, and even brain. They damage the tissues and cause formation of abscess. These conditions are named as Hepatitic amoebiasis, Pulmonary amoebiasis, Cerebral amoebiasis, respectively depending on the organ infected.