Clinical Gastroenterology Vol.19 No.8(2-4)

Theme Infectious Enterocolitis
Title Infectious Enterocolitis Caused by Protozoa
Publish Date 2004/07
Author Naoto Miyake Department of Gastroenterology, JR Sendai Hospital
Author Masao Ando Department of Gastroenterology, JR Sendai Hospital / Department of Gastroenterology, Kanagami Hospital
Author Koichi Sugiyama Department of Gastroenterology, JR Sendai Hospital
[ Summary ] Amebiasis, giardiasis and cryptosporidiosis are major infectious enterocolitis caused by protozoa. Transmission of protozoa occurs by ingestion of contaminated water or food. In Japan, infectious enterocolitis caused by protozoan is seen to be important as a form of imported enteric infection. Recently, this condition has been seen to be important as a form of infection in male homosexuals, also. In immunocompromised patients, infection is much more serious than in normal hosts.
Amebiasis is caused by infection with the pathogenic agent Entamoeba histolytica. Amebic colitis is characterized by the subacute onset of bloody diarrhea, abdominal tenderness, and tenesmus. The most characteristic fiding with amebic colitis is erosions, such as verruca, which is frequently seen in the rectum and cecum. Histologically, amebiasis is diagnosed by detection of cysts or trophozoites in the stool or in biopsy specimens. Serology for antiamebic antibodies is useful for diagnosis, too. The nitroimidazoles, metronidazole and tinidazole, are effective for treatment of amebiasis. However, if metronidazole is not effective in eradicating intestinal infection, dehyrroimetine should be used.
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