Intestinal amoebiasis - amoebic dysentery Most amoebic infections are asymptomatic. The incubation period of amoebiasis ranges from 2 weeks to many years, followed by a chronic course with abdominal pains and two or more unformed stools a day. Offensive diarrhoea, alternating with constipation, and blood or mucus in the stool are common. There may be abdominal pain, especially in the right lower quadrant (which may mimic acute appendicitis). A dysenteric presentation with passage of blood, simulating bacillary dysentery or ulcerative colitis, occurs paicularly in older people, in the puerperium and with super-added pyogenic infection of the ulcers. Amoebic liver abscess The abscess is usually found in the right hepatic lobe. There may not be associated diarrhoea. Early symptoms may be only local discomfo and malaise; later, a swinging temperature and sweating may develop, usually without marked systemic symptoms or signs. An enlarged, tender liver, cough and pain in the right shoulder are characteristic but symptoms may remain vague and signs minimal. A large abscess may penetrate the diaphragm, rupturing into the lung, and may be coughed up through a hepatobronchial fistula. Rupture into the pleural or peritoneal cavity, or rupture of a left lobe abscess in the pericardial sac, is less common but more serious. Ref Davidson edition23rd pg 287