Convulsions due to lowered blood sugar levels shortly precede death. Affected birds suffer losses in weight and survivors remain stunted for long periods. Dehydration and emaciation are the principle gross lesions. The intestine usually appears to have lost tone with local bulbous areas of congestions. Intestinal contents usually are thin and watery.
Diagnosis depends upon history, symptoms and microscopic examination of intestinal contents.
A definite diagnosis cannot be made unless typical flagellates can be demonstrated in intestinal contents taken from the duodenum area. Most flagellates in the ceca are nonpathogens. Younger groups should be cared for first if several groups are involved. The disease usually does not respond well to treatment, but broad spectrum antibiotics have been found useful in some outbreaks. In certain respects, the disease resembles true malaria, but birds are the sole hosts of the genus Leucocytozoon .