Manoshi Perera¹, Hemalatha Varadhan^1,2, Aileen Oon¹

¹Microbiology, NSW Health Pathology, John Hunter Hospital, Newcastle, NSW, Australia; ²University of Newcastle, Newcastle, NSW, Australia 

 

Syndromic molecular testing for diagnosis of CNS infections have been advantageous given high sensitivity and rapid diagnostics, however challenges remain with interpretation. A post-implementation evaluation of the CSF BioFire panel in an adult and paediatric population was performed. The aims were to assess the epidemiology of all targets, and correlate laboratory parameters with results from HHV-6 detection to identify opportunities to apply diagnostic stewardship. A retrospective observational study was conducted of CSF NAAT results, performed at a referral laboratory in NSW, Australia between March 2022 and July 2023. Laboratory and medical record data was extracted. A total of 1490 CSF specimens were identified, with a positive NAAT in 287 (19.3%). Non-neonate specimens with a WCC above normal range had a higher proportion of NAAT positive rates (35.3%) compared to those with a WCC <5 x106 cells/L (6.5%)(p<0.001). A positive NAAT result was detected in 90 (39.1%) specimens in neonates – most frequently with enterovirus and parechovirus. Forty-eight (48/1490) specimens had HHV-6 detected, with a median age of 24.3 years (IQR 0.5-58.7) at collection and 10 specimens with a documented immunocompromised status. This study highlights the caution required when utilising high sensitivity, rapid diagnostics for detection of CSF pathogens without associated diagnostic stewardship strategies.

 

Author contributions: The project was conceived and designed by M.P, H.V. and A.O. Data curation was performed by M.P. and formal analysis by M.P. and A.O. The manuscript was drafted by M.P. and edited and revised by all authors.