Validation of an Isothermal Amplification Platform for Microbial Identification and Antimicrobial Resistance Detection in Blood: A Prospective Study

Harish M Maheshwarappa; Prasadini Guru; Reddy Sailaja Mundre; Nima Lawrence; Snehali Majumder; Alben Sigamani; C N Anupama; Sudeshna Adak

doi:10.5005/jp-journals-10071-23761

Validation of an Isothermal Amplification Platform for Microbial Identification and Antimicrobial Resistance Detection in Blood: A Prospective Study

Indian J Crit Care Med. 2021 Mar;25(3):299-304. doi: 10.5005/jp-journals-10071-23761.

Authors

Harish M Maheshwarappa¹, Prasadini Guru², Reddy Sailaja Mundre³, Nima Lawrence³, Snehali Majumder⁴, Alben Sigamani⁴, C N Anupama³, Sudeshna Adak³

Affiliations

¹ Department of Intensive Care Medicine, Narayana Hrudayalaya, Bangalore, Karnataka, India.
² Department of Laboratory Medicine, Microbiology and Serology, Narayana Hrudayalaya, Bangalore, Karnataka, India.
³ OmiX Research and Diagnostics Laboratories, Bangalore, Karnataka, India.
⁴ Department of Clinical Research, Narayana Hrudayalaya, Bangalore, Karnataka, India.

Abstract

Background: Recent advances in nucleic acid amplification technique (NAAT)-based identification of pathogens in blood stream infections (BSI) have revolutionized molecular diagnostics in comparison to traditional clinical microbiology practice of blood culture. Rapid pathogen detection with point-of-care diagnostic-applicable platform is prerequisite for efficient patient management. The aim of the study is to evaluate an in-house developed, lyophilized OmiX-AMP pathogen test for the detection of top six BSI-causing bacteria along with two major antimicrobial resistance (AMR) markers of carbapenem and compare it to the traditional blood culture-based detection. Materials and methods: One hundred forty-three patients admitted to the Medical Intensive Care Unit, Narayana Hrudayalaya, Bangalore, with either suspected or proven sepsis, of either gender, of age ≥18 years were enrolled for the study. Pathogen DNA extracted from blood culture sample using OmiX pReP method was amplified at isothermal conditions and analyzed in real time using OmiX Analysis software. Results: Among the processed 143 samples, 54 were true negative, 83 were true positive, 3 were false negative, and 2 were false positive as analyzed by OmiX READ software. Gram-negative bacteria (91.3%) and gram-positive bacteria (75%) were detected with 100% specificity and 95.6% sensitivity along with the AMR marker pattern with a turnaround time of 4 hours from sample collection to results. Conclusion: OmiX-AMP pathogen test detected pathogens with 96.5% concordance in comparison to traditional blood culture. Henceforth, OmiX-AMP pathogen test could be used as a readily deployable diagnostic kit even in low-resource settings. How to cite this article: Maheshwarappa HM, Guru P, Mundre RS, Lawrence N, Majumder S, Sigamani A, et al. Validation of an Isothermal Amplification Platform for Microbial Identification and Antimicrobial Resistance Detection in Blood: A Prospective Study. Indian J Crit Care Med 2021;25(3):299-304.

Keywords: Blood stream infection; Diagnosis; Isothermal amplification; Pathogen detection; Sepsis.