Rapid Detection of Acute Infection in Immunosuppressed Renal Patients with IRIDICA: A Pilot Study.
1Renal, Royal London Hospital, Barts Health Trust, London, United Kingdom
2Microbiology, Barts Health Trust, London, United Kingdom.
Meeting: 2016 American Transplant Congress
Abstract number: D102
Keywords: Bacterial infection, Kidney transplantation
Session Information
Session Name: Poster Session D: Fungi, PJP, Mycobacteria, Infection Risk Factors, Vaccination and Donor Derived Infections
Session Type: Poster Session
Date: Tuesday, June 14, 2016
Session Time: 6:00pm-7:00pm
Presentation Time: 6:00pm-7:00pm
Location: Halls C&D
Background
The Abbott IRIDICA bacterial bloodstream (BAC BSI) assay is a rapid semi-quantitative diagnostic test that is able to detect over 800 significant pathogens using PCR and ESI-MS to identify bacterial and fungal nucleic acids from blood samples. This allows early targeted treatment of sepsis. We compared the current gold standard blood culture system to the IRIDICA technique in detecting bacterial pathogens in pyrexial immunosuppressed patients.
Material/Methods
Immunosuppressed patients who were known to the Royal London Renal Unit and presented with a fever of more than 38C
between January and December 2015 were included. A 5ml EDTA blood sample was taken at the same time as blood cultures.
The EDTA sample was stored at -20C whilst awaiting retrospective analysis on the IRIDICA system. The IRIDICA technician was blinded to the results of the blood culture analysis.
Results
30 samples from 26 immunosuppressed patients are included in this analysis, of which 23 were transplant recipients. The remaining 3 were on treatment for glomerulonephritis. 10 (33%) samples were positive by IRIDICA compared with only 7 (23%) by blood culture analysis. Compared to blood culture, the IRIDICA assay demonstrated a sensitivity and specificity of 43% and 74% respectively. The positive predictive value was 33% and the negative predictive value was 81%. However half of those patients with a positive blood culture, but negative IRIDICA sample did not have enough information available to determine their clinical significance.
2 patients (20%) with positive IRIDICA samples had received antimicrobial therapy in the preceding 30 days prior to sampling. The corresponding blood culture detected no growth after 5 days.
Conclusions
We conclude the IRIDICA technique allows fast identification of pathogens compared to the gold standard blood culture technique, which can take up to 5 days. Previous antimicrobial therapy does not affect the detection of pathogens using the IRIDICA assay. A negative IRIDICA result is effective in excluding infection in pyrexial immunosuppressed patients.
CITATION INFORMATION: Hassan S, Adwaney A, Massiah A, Murphy R, Law S, Mohd-Afzal S, Wilks M, Thuraisingham R. Rapid Detection of Acute Infection in Immunosuppressed Renal Patients with IRIDICA: A Pilot Study. Am J Transplant. 2016;16 (suppl 3).
To cite this abstract in AMA style:
Hassan S, Adwaney A, Massiah A, Murphy R, Law S, Mohd-Afzal S, Wilks M, Thuraisingham R. Rapid Detection of Acute Infection in Immunosuppressed Renal Patients with IRIDICA: A Pilot Study. [abstract]. Am J Transplant. 2016; 16 (suppl 3). https://atcmeetingabstracts.com/abstract/rapid-detection-of-acute-infection-in-immunosuppressed-renal-patients-with-iridica-a-pilot-study/. Accessed May 9, 2025.« Back to 2016 American Transplant Congress