S. mansoni was first noted by Theodor Maximillian Bilharz in Egypt in 1851, while discovering S. haematobium. Sir Patrick Manson identified it as unique species in 1902. Louis Westenra Sambon gave the name Schistosomum mansoni in 1907 in honour of Manson. Structure
Adult
Schistosomes, unlike other trematodes, are long and cylindrical worms and are sexually dimorphic. The male S. mansoni is approximately 1 cm long (0.6–1.1 cm) and is 0.1 cm wide. It is white, and it has a funnel-shaped oral sucker at its anterior end followed by a second pediculated ventral sucker. The external part of the worm is composed of a double bilayer, which is continuously renewed as the outer layer, known as the membranocalyx, and is shed continuously. The tegument bears a large number of small tubercules. The suckers have small thorns in their inner part as well as in the buttons around them. The male genital apparatus is composed of 6 to 9 testicular masses, situated dorsally. There is one deferent canal beginning at each testicle, which is connected to a single deferent that dilates into a reservatory, the seminal vesicle, located at the beginning of the gynaecophoric canal. The copula happens through the coaptation of the male and female genital orifices.The female has a cylindrical body, longer and thinner than the males (1.2 to 1.6 cm long by 0.016 cm wide). It has the general appearance of a roundworm. The female parasite is darker, and it looks gray.
Diversion colitis is an inflammation of the colon which can occur as a complication of ileostomy or colostomy, where symptoms may occur between one month and three years following surgery. It also occurs frequently in a neovagina created by colovaginoplasty, with varying delay after the original procedure. Despite the presence of a variable degree of inflammation the most suggestive histological feature remains the prominent lymphoid aggregates. Symptoms and signs
People may be asymptomatic but common symptoms are abdominal discomfort, anorectal pain, mucous discharge and rectal bleeding that develops from the inflamed mucosa of the distal, unused colon. Diagnosis
Diagnosis is aided by knowing the full clinical history. Treatment
In many milder cases after ileostomy or colostomy, diversion colitis is left untreated and disappears naturally. Possible pharmacologic treatments include short-chain fatty acid irrigation, steroid enemas and mesalazine. For surgical candidates, reanastomosis is a reversal procedure carried out to restore bowel continuity that effectively halts the symptoms of diversion colitis. == References ==