Background: CNS infections requires a fast and reliable diagnosis. BIOFIRE® Meningitis/Encephalitis (ME) Panel (bioMérieux) is a rapid multiplex PCR platform which detects 14 pathogens in cerebrospinal fluid (CSF) in patients with ME. The aims of this study were to assess the performances of this test in comparison with routine methods (RM). In case of discrepancy an analysis based on patient records and laboratory results was performed.
Materials/methods: From January to November 2019 at Hospital Lozano Blesa, Zaragoza-Spain, CSF samples of patients with ME suspicion were tested with the RM: gram stain, India ink stain (IIS), bacterial culture, Herpesviridae and Enterovirus PCR (Entherpex Genomica®) and Cryptococcus sp. (Csp) antigen immunochromatography (IC) (RDT CryptoPS, BIO-RAD). Result were compared with BIOFIRE® ME Panel.
Results: Fifty-three CSF from 49 patients were tested. RM global positivity rate was 14/49 (28.6%) versus 16/49 (32.7%) for BIOFIRE® ME Panel. There was a good concordance between both methods in 10 samples (3 Enterovirus, 1 VZV, 2 HSV-1, 2 Streptococcus pneumoniae (SP) and 2 Listeria monocytogenes). Discrepancy was found in 5 samples. SP was detected by BIOFIRE® ME Panel and not by culture in a CSF with bacterial pattern. In two samples VZV was detected by BIOFIRE® ME Panel and not by PCR (Genomica®), in both cases, CFS had a viral pattern, and one of the patients had vesicular lesions. In one non pathological CFS, false positive HSV-2 was detected for Genomica® but not by BIOFIRE® ME Panel. In one sample with lymphocytes, Csp was detected by IC and not with BIOFIRE® ME Panel or IIS, this sample was BIOFIRE® ME Panel negative at the arrival to the laboratory; however, sample showed a BIOFIRE® ME Panel C. neoformans/gattii and IIS positive result after incubation for 48h at 37°C.
Conclusions: Discrepancy between BIOFIRE® ME Panel and RM were detected for SP, VZV, HSV-2 and Csp. BIOFIRE® ME Panel showed more sensitivity for VZV and SP. BIOFIRE® ME Panel sensitivity was deficient for Csp, requiring other methods to confirmed. BIOFIRE® ME Panel is a useful method in emergency cases; however, its results should be confirmed and always interpreted according to the CSF biochemistry results.