|TE LOO, MAROESKA - Radboud University|
|LOOS, SEBASTIAN - University Of Hamburg|
|SCAVIA, GAIA - University Of Bologna, Italy|
|BRIGOTTI, MAURIZIO - University Of Bologna, Italy|
|LEVTCHENKO, ELENA - University Of Leuven|
|MONNENS, LEO - Radboud University|
Submitted to: Acta Paediatrica
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/8/2015
Publication Date: 11/2/2015
Publication URL: http://handle.nal.usda.gov/10113/5678140
Citation: He, X., Quinones, B., Te Loo, M., Loos, S., Scavia, G., Brigotti, M., Levtchenko, E., Monnens, L. 2015. Serum Shiga toxin 2 values in patients during the acute phase of diarrhoea-associated hemolytic uremic syndrome. Acta Paediatrica. 104(12):e564-568.
Interpretive Summary: Shiga toxin-producing E. coli are a group of food-borne bacteria that cause hemorrhagic colitis and hemolytic-uremic syndrome (HUS) and Stx is one the most important virulence factors that induce these diseases. This research aims to investigate the relationship between Stx concentration in human sera and the risk of development of HUS. Our results indicate that Stx2 was found in 8 out of 16 children with HUS, suggesting that about 50% of children admitted to the clinic with D+HUS had very low concentration of Stx2 (below detection level) in serum due to the short serum half-life time. A more frequent sampling might be required for toxin detection. In addition, results from this study indicate that high level of Stx2 were present in sera of HUS patients’ family members during the diarrhea period but before development of HUS, suggesting that further studies should focus on the diarrhea period preceding HUS. This study will help in elucidating the role of Stx in HUS and may lead to improved methods for the diagnosis of HUS.
Technical Abstract: Aim: Shiga toxins, Stx-1 and Stx-2, by injuring endothelial cells mainly of the glomeruli, are considered as the cause of D+HUS. After passing through the intestinal wall, Stxs have to be delivered via the systemic circulation to the target organs. This study was aimed at measuring free Stx-2 in serum of children affected by HUS due to Stx-2 producing Escherichia coli. Serum was collected immediately after admission to the clinic in the acute phase of HUS. Methods: The concentration of free Stx-2 was measured in serum of 16 children using a sandwich ELISA. Family members of 2 children were also investigated. In these family members the relative toxicity of Stx-2 was assessed by a Vero cell-based fluorescent assay. Results: In 8 out of 16 investigated children Stx-2 was demonstrated in their serum. In 6 family members not showing symptomatic HUS, Stx-2 was detected in 4 with an extremely high level in 2. In the 2 family members with the highest Stx-2 concentration the functional activity was the most pronounced. Conclusion: We demonstrated an absent or a rather low concentration of Stx-2 in serum of children admitted to the clinic with D+HUS. The high concentration of Stx-2 in family members without HUS but mostly with watery diarrhea, together with a raised functional activity, is in line with the concept of early injury by Stx-2 during the first days of the infection.