Prediction of Infectious Agents in the Biofire® FilmArray bioMérieux Meningitis/Encephalitis Panel Based on Clinical Syndrome and Cerebrospinal Fluid Parameters: a Diagnostic Stewardship Proposal.

Prediction of Infectious Agents in the Biofire® FilmArray bioMérieux Meningitis/Encephalitis Panel Based on Clinical Syndrome and Cerebrospinal Fluid Parameters: a Diagnostic Stewardship Proposal.

Background: Infections of the central nervous system (CNS) are associated with high morbidity, mortality, and high resource consumption. The BioFire FilmArray is a molecular diagnostic panel capable of identifying 14 pathogens in approximately one hour, including bacteria, viruses, and fungi. However, it is not yet widely available in the Brazilian public health system.

Objective: The primary objective of this study is to evaluate the pre-test probability of positivity of the Biofire FilmArray bioMérieux Meningitis/Encephalitis panel in patients with clinical syndrome of meningitis and/or encephalitis and pleocytosis (CSF ≥ 5 cells).

As secondary objectives, the study aims to:

Determine the clinical impact of using the panel through variables such as total hospital stay and length of stay in the intensive care unit.

Compare the duration of antibiotic use in non-bacterial cases between groups. Compare the time to reduction of acyclovir use in etiologies without proven benefit.

Compare the time for identification of the causative pathogen and mortality rates between the study groups.

Perform a cost-effectiveness analysis of the test. Compare the request for imaging exams, such as brain MRI and CT scan, between the groups.

Methods: This is a prospective, transversal, and multicenter study conducted at Santa Casa de Porto Alegre and Hospital Dom João Becker. Patients will be compared with a retrospective cohort used as a control group.

This will be a prospective study, conducted at Santa Casa de Porto Alegre, a philanthropic tertiary university hospital with 1,400 beds and at Hospital Dom João Becker, which has 173 inpatient beds and 20 ICU beds. Adult patients with clinical symptoms compatible with CNS infection that began less than 30 days prior, for whom cerebrospinal fluid collection has been indicated by the attending physician, will be included. Participation in the study will be subject to the signing of an informed consent form (ICF) by the patient or their legal representative. The patient will then be included in the study. Samples will be processed with qualitative and quantitative cytology, protein, glucose, and lactate analysis, as well as specific tests as requested by the attending physician. Patients will be compared with a retrospective cohort used as a control group (patients with clinical CNS infection who underwent cerebrospinal fluid collection but were not tested with the FilmArray panel) over the past 4 years.

Inclusion Criteria:

Patients aged 18 years or older, of any gender.

Presence of at least two of the following symptoms: fever, lethargy, altered level of consciousness, seizures, acute focal deficit, signs of meningeal irritation, or headache.

Symptoms must have started within the last 30 days.

Obligatory presence of pleocytosis (CSF white blood cell count ≥ 5 cells/mm³).

Provision of written Informed Consent (TCLE) by the patient or their legal representative.

Exclusion Criteria:

• Failure to sign the Informed Consent Form.

Clinical manifestations lasting more than 30 days.

Patients under 18 years of age.

Patients who have undergone neurosurgery within 30 days prior to the onset of symptoms (applies to both prospective and control groups).