# Epidemiology of healthcare-associated ventriculitis and meningitis (HCAVM) and community-acquired meningitis/encephalitis and evaluation of an off-label PCR panel for HCAVM diagnosis

## TL;DR

This study examines the causes of CNS infections after surgery and evaluates a repurposed test for rapid diagnosis.

## Contribution

The study evaluates the utility of repurposing a PCR panel for diagnosing healthcare-associated CNS infections.

## Key findings

- HCAVM cases were mainly caused by bacteria and fungi linked to bloodstream infections.
- The repurposed PCR panel showed 90% sensitivity when Gram stain was positive but only 50% when negative.
- CAME cases were primarily caused by herpesviruses and Cryptococcus, differing from HCAVM.

## Abstract

Healthcare-associated ventriculitis and meningitis (HCAVM) is associated with high morbidity and mortality, but rapid diagnostic tests intended to cover microorganisms that typically cause HCAVM are not commercially available. We sought to evaluate the etiology of HCAVM compared to community-acquired meningitis/encephalitis (CAME) at our healthcare system, and to study the utility of repurposing a multiplex molecular panel intended for positive blood cultures for HCAVM cases. Our epidemiologic review demonstrated that HCAVM cases were primarily caused by bacteria and fungi also associated with bloodstream infections, in contrast with CAME cases, which were primarily caused by herpesviruses and Cryptococcus. Eighty-two cerebrospinal fluid specimens, including 43 from HCAVM cases, were tested using the BioFire Blood Culture Identification 2 panel, with approximately 90% sensitivity when organisms were seen in the Gram stain but only approximately 50% sensitivity when the stain was negative, compared to standard-of-care testing.

Rapid diagnostic tests are not commercially available that are intended for use in patients who develop infections of their central nervous system (CNS) after CNS surgery or the placement of hardware for CNS issues. Because these types of infections are typically very serious, we attempted to repurpose a commercial assay intended for a different purpose (bloodstream infections) to help generate rapid results for these important CNS infections.