Background: Central Nervous System (CNS) infections, including meningitis and encephalitis, are associated with significant morbidity and mortality; rapid and accurate detection of pathogens in the cerebrospinal fluid (CSF) can improve clinical care. The aim of this two-year study was to prospectively evaluate the multiplex PCR BIOFIRE® Meningitis/Encephalitis (ME) Panel for the rapid (1 h) and simultaneous detection in CSF of 14 life-threatening agents (6 bacteria, 7 viruses and 1 yeast) in comparison with the reference methods currently used in case of CNS infection suspicion.
Materials/methods: A total of 173 CSFs (November 2017-November 2019) belonging to as many patients were analyzed by BIOFIRE® ME Panel in comparison with the reference methods for bacteria, including the mandatory direct microscopic examination (DME) and the identification by MALDI-TOF MS from either agar or liquid conventional cultures. For virus confirmation, when a BIOFIRE® ME Panel positive result for virus was obtained, the samples were submitted to agent specific PCRs (except for paraechovirus not routinely detected).
Results: The BIOFIRE® ME Panel gave a positive result in 24 cases (13.9%), in 23 cases (95.8%) for a single agent (5 Streptococcus pneumoniae, 3 Haemophilus influenzae, 2 Neisseria meningitidis, 1 Streptococcus agalactiae, 7 enterovirus, 2 human herpesvirus 6, 2 varicella zoster virus and 1 paraechovirus) and in 1 case (4.2%) for H. influenzae in combination with cytomegalovirus. The BIOFIRE® ME Panel positive results were concordant, with regard to the agents recognized by the molecular assay, with those obtained by the reference methods in all cases (83.3%) except in 4 culture-negative cases: 2 samples containing S. pneumoniae (DME-positive for Gram positive cocci, patients under antibiotic therapy) and 2 DME-negative samples containing S. pneumoniae and H. influenzae, respectively. In addition, the reference bacterial methods gave positive results in 12 CSFs, all agents not targeted by BIOFIRE® ME Panel.
Conclusions: This study suggests that BIOFIRE® ME Panel, despite high costs, can have comparable diagnostic yield and more rapid time-to-diagnosis than conventional methods in patients with suspected CNS infection and proves the potential for significant clinical impact including optimization of antimicrobial therapy and reduction of unnecessary use. However, for the definitive diagnosis reference methods remain mandatory for both bacteria and viruses.