Infectious Diseases and Clinical Microbiology, vol.1, no.3, pp.128-133, 2019 (Peer-Reviewed Journal)
ABSTRACT
Objective: Timely diagnosis is crucial for successful treatment of infections. Contemporary
diagnostics of clinically significant infections relies on a variety of laboratory-based tests.
However, the routine microbiological methods, per se are not always confirmatory for the
accurate diagnosis in some cases with a significant time delay. Rapid detection of causative
agents using nanopore-based metagenomic sequencing is reported in a case of suspected
tuberculosis not confirmed using conventional microbiology diagnostics, and in a case of
suspected brucellosis with delayed confirmation by conventional microbiology.
Materials and Methods: This report includes two cases. Patient-1 was clinically diagnosed
with peritoneal tuberculosis while Patient-2 had relapsing brucellosis. Cultures and PCR
were negative for the peritoneal fluid of Patient-1. Serological determinants for brucellosis
were under the thresholds for Patient-2. The blood culture was positive for Brucella spp;
however, the results were available only after seven days. Peritoneal fluid and blood sample
were obtained from Patient-1 and Patient-2, respectively. Total DNA was extracted using
commercial kits. Shotgun metagenomic sequencing was performed using Oxford Nanopore
Technologies. Read-event data were base-called by the software Metrichor using workflow
v2.39.3.
Results: For Patient-1, the first Mycobacterium tuberculosis reads were confidently detected in
20 minutes, for Patient-2 the first Brucella melitensis read was detected at 30-minutes-timepoint. Overall, the pathogens were detected within 6 hours. We demonstrated a real-time
nanopore sequencing technology for the rapid detection of infectious agents in two crucial
cases where traditional microbiological methods failed to reveal the pathogens.
Conclusion: In this report, we present that real-time sequencing can not only detect
conventionally unrevealed pathogens, but it can achieve this in a tight time-frame.
Therefore, it could be said that the nanopore sequencing has the promise to enhance our
ability to diagnose infectious diseases.