Abstract: FR-PO120

Glyco-iELISA: A Novel Assay to Detect STEC-HUS

Session Information

Category: Acute Kidney Injury

  • 003 AKI: Clinical and Translational

Authors

  • Wijnsma, Kioa L., Radboud medical center, Nijmegen, Netherlands
  • Veissi, Susan, Radboud medical center, Nijmegen, Netherlands
  • Ugalde, Juan E, Universidad Nacional de San Martin, San Martin, Argentina
  • Comerci, Diego J., Universidad Nacional de San Martin, San Martin, Argentina
  • Van De Kar, Nicole, Radboud medical center, Nijmegen, Netherlands
  • Van den heuvel, Bert, Radboudumc, Nijmegen, Netherlands
Background

Differentiation between hemolytic uremic syndrome (HUS) caused by Shiga toxin-producing E. coli (STEC-HUS) or a dysregulated complement system (atypical HUS; aHUS) is a clinical conundrum. As aHUS, whose treatment requires the highly expensive orphan drug eculizumab, is a diagnoses per exclusionem, a method to reliably detect STEC infection is warranted.
Since the current golden standard (fecal diagnostics; FD) for the detection of STEC infection has important drawbacks, serological detection of antibodies against STEC-associated lipopolysaccharides by ELISA (LPS-ELISA) has proven its value. However, LPS-ELISA have important limitations. Therefore, we have developed and evaluated the diagnostic value of ELISA employing recombinant glycoproteins of STEC-associated LPS (glyco-iELISA).

Methods

In this retrospective study, patients (n=61) who presented with clinical STEC-HUS in the Radboudumc, Nijmegen, Netherlands, between 1990-2014 were included. Clinical, diagnostic and follow up data were gathered. Both LPS-ELISA and glyco-iELISA were employed to detect IgM antibodies against the most common serotype of STEC (O157).

Results

FD, LPS-ELISA, and glyco-iELISA identified STEC infection in respectively, 53%, 64%, and 75% of patients. Glyco-iELISA provided evidence of STEC infection in 7 (11%) and 20 (33%) additional patients when compared to LPS-ELISA or FD, respectively. Combining the glyco-iELISA with FD identified STEC infection in 89% of patients. The glyco-iELISA appeared highly reproducible and reliable, as the intra- and inter-assay variability was low.

Conclusion

The glyco-iELISA is a highly sensitive and accurate serological method to detect STEC in HUS patients. Combined with FD, the glyco-iELISA improves STEC detection by 36%. Thus, the glyco-iELISA may drastically limit the unnecessary use of eculizumab in STEC-HUS.