- Chronic diarrhea of unknown etiology
- Patient has a wide variety of symptoms of unknown etiology
- Testing for Stx1 and Stx2 Shiga Toxins in the bowel
Shiga toxins are a family of related toxins with two major groups, Stx1 and Stx2 which are produced by S. dysenteriae and the Shigatoxigenic group of Escherichia coli (STEC). Pathogenic STEC are associated with severe abdominal cramping, diarrhea (watery and/or bloody), low-grade fever, vomiting and more serious outbreaks of life-threatening hemorrhagic colitis and hemolytic uremic syndrome leading to kidney failure. The immunoassay used for this test is sensitive and specific for the detection of both Shiga toxins Stx1 and Stx2 in fecal samples and encompasses all pathogenic strains of E. coli.
STEC is a major cause of sporadic cases of disease as well as serious outbreaks worldwide. Major transmission modes include contaminated food or water, person-to-person spread (nursing homes, day care setting) or animal to person contact. The most common sources of infection by STEC include undercooked beef and beef products; cattle are major carriers. Other wild and domestic animals, including birds, can also carry these bacteria. STEC and its Shiga toxins can be destroyed by heat. Food-borne outbreaks have been traced back to undercooked hamburgers, unpasteurized fruit juices, salad bars, salami, and unpasteurized milk. STEC strains are usually self-limiting, lasting an average of about 8-10 days.