The main symptom of dysentery is frequent near-liquid diarrhea flecked with blood, mucus, or pus. Other symptoms include:
- sudden onset of high fever and chills
- abdominal pain
- cramps and bloating
- flatulence (passing gas)
- urgency to pass stool
- feeling of incomplete emptying
- loss of appetite
- weight loss
Other symptoms may be intermittent and may include recurring low fevers, abdominal cramps, increased gas, and milder and firmer diarrhea. You may feel weak and anemic, or lose weight over a prolonged period (emaciation). Mild cases of bacillary dysentery may last 4 to 8 days, while severe cases may last 3 to 6 weeks. Amoebiasis usually lasts about 2 weeks.
Bacillary dysentery symptoms begin within 2 to 10 days of infection. In children, the illness starts with fever, nausea, vomiting, abdominal cramps, and diarrhea. Episodes of diarrhea may increase to as much as once an hour with blood, mucus, and pus in the child's stool. Vomiting may result in rapid and severe dehydration, which may lead to shock and death if not treated. Signs of dehydration include an extremely dry mouth, sunken eyes, and poor skin tone. Children and infants will be thirsty, restless, irritable, and possibly lethargic. Children may also have sunken eyes and may not be able to produce tears or urine, the latter appearing very dark and concentrated.
Complications from bacillary dysentery include delirium, convulsions, and coma. A very severe infection like this can be fatal within 24 hours. However, the vast majority of infections are self-limited and resolve spontaneously without treatment.
People with amoebic dysentery may experience other problems associated with amoebiasis. The most frequent complication results when parasites spread to the liver, causing an amoebic abscess. In this case, you would have a high fever and experience weight loss and right shoulder or upper abdominal pain. If the infection of the bowel is especially virulent, the intestinal ulcerations may lead to bowel perforation and death. The parasites may rarely spread through the bloodstream, causing infection in the lungs, brain, and other organs.