Outcomes of implementation of the FilmArray meningoencephalitis panel in a tertiary hospital between 2017 and 2020

Background

Acute meningoencephalitis is encountered commonly in the acute hospital setting and is associated with significant morbidity and mortality, in addition to significant healthcare costs. Multiplex PCR panels now allow syndromic testing for central nervous system infection. The BioFire® FilmArray® Meningoencephalitis (ME) allows testing of 14 target pathogens using only 0.2mls of cerebrospinal fluid (CSF). We conducted a retrospective observational study to assess the performance of the assay and secondarily to observe the clinical utility of negative results by comparing clinical outcomes of aseptic meningitis to bacterial and viral meningoencephalitis.

Methods

Data for CSF samples tested using the FilmArray ME panel from October 2017 to October 2020 were analysed. Detection of bacterial and viral targets was analysed. Admission to critical care area, 90-day readmission rates, average length of stay and 30-day and 90-day mortality were analysed for three groups with following diagnoses: bacterial meningitis, viral meningoencephalitis, or aseptic meningitis.

Results

From October 2017 to October 2020, 1926 CSF samples were received in the Clinical Microbiology laboratory. Of those, 543 CSF samples from 512 individual patients were tested using the FilmArray ME panel. Twenty-one bacterial targets and 56 viral targets were detected during the study period. For viral targets, the cumulative specificity was 98.9% (95% confidence interval: 93.1–99.9) when compared to the reference laboratory methods. The outcomes for 30- and 90-day mortality of the aseptic meningitis group were non-inferior relative to the viral meningoencephalitis and bacterial meningitis group. Patients with bacterial meningitis had a longer average length of stay. Aseptic meningitis was associated with a higher 90-day readmission rate than the other 2 groups, but without statistical significance.

Conclusion

In our hands, implementation of the FilmArray ME panel was relatively straightforward. We experienced a transition in our workflow processes that enabled streamlining of CSF diagnostics and the safe removal of Gram staining in those samples being tested by this molecular assay. Coupled to this improvement, there was a positive clinical impact on patient care due to rapid turnaround time to results.

Assessment of the FilmArray® multiplex PCR system and associated meningitis/encephalitis panel in the diagnostic service of a tertiary hospital

Rapid and accurate diagnosis of meningitis/encephalitis (M/E) is essential for successful patient outcomes. The FilmArray® meningitis/encephalitis Panel (MEP) is a multiplexed PCR test for simultaneous, rapid detection of pathogens directly from cerebrospinal fluid (CSF) samples. 94 prospectively collected CSF specimens from patients with clinical suspicion of infective M/E underwent testing for 14 pathogens simultaneously, including Escherichia coli, Haemophilus influenzae, Neisseria meningitidis, and Varicella zoster. MEP demonstrated 95% agreement with current PCR methods, resulting in 16 diagnosed cases of M/E. Typically, the FilmArray® MEP results were delivered within approximately one hour, contrasting with current practices taking up to 5.6 days. Given the significant morbidity and mortality associated with delayed diagnosis of central nervous system infections, the FilmArray® MEP is a useful addition to the diagnostic capabilities of a clinical microbiology department.

The association between platelet dysfunction and adverse outcomes in cardiac surgical patients

Haemostatic activation during cardiopulmonary bypass is associated with prothrombotic complications. Although it is not possible to detect and quantify haemostatic activation directly, platelet dysfunction, as measured with point-of-care-assays, may be a useful surrogate. In this study, we assessed the association between cardiopulmonary bypass-associated platelet dysfunction and adverse outcomes in 3010 cardiac surgical patients. Platelet dysfunction, as measured near the end of the rewarming phase of cardiopulmonary bypass, was calculated as the proportion of non-functional platelets after activation with collagen. Logistic regression and multivariable analyses were applied to assess the relationship between platelet dysfunction and a composite of in-hospital death; myocardial infarction; stroke; deep vein thrombosis or pulmonary embolism; and acute kidney injury (greater than a two-fold increase in creatinine). The outcome occurred in 251 (8%) of 3010 patients. The median (IQR [range]) percentage platelet dysfunction was less for those without the outcome as compared with those with the outcome; 14% (8-28% [1-99%]) vs. 19% (11-45% [2-98%]), p < 0.001. After risk adjustment, platelet dysfunction was independently associated with the composite outcome (p < 0.001), such that for each 1% increase in platelet dysfunction there was an approximately 1% increase in the composite outcome (OR 1.012; 95%CI 1.006-1.018). This exploratory study suggests that cardiopulmonary bypass-associated platelet dysfunction has prognostic value and may be a useful clinical measure of haemostatic activation in cardiac surgery.

Detection of Neisseria meningitidis in a paediatric patient with septic arthritis using multiplexed diagnostic PCR targeting meningitis/encephalitis (ME)

BACKGROUND

Neisseria meningitidis is associated with meningitis and septicemia. Septic meningococcal arthritis is relatively uncommon and its diagnosis associated with clinical and microbiological challenges. Early recognition and treatment is required to prevent joint destruction.

PURPOSE

We describe a case of an eleven-year-old boy with septic arthritis and the first reported use of a multiplexed diagnostic PCR test, capable of simultaneous rapid detection of 14 pathogens directly from CSF samples, to determine presence of N. meningitides in a synovial fluid sample.

RESULTS

In this case, blood cultures and an aspiration of the joint fluid were negative for microbial growth, but leucocytes were present. Analysis of samples using the multiplexed FilmArray^® meningitis/encephalitis panel (MEP) proved positive for N. meningitidis. In parallel, samples forwarded to an accredited reference laboratory confirmed the findings by bacterial 16S rRNA gene amplification and sequencing. Subsequent to these results, empiric treatment with intravenous flucloxacillin was discontinued and oral amoxicillin administered for 1 month. The status of the patient improved with etiology-based antimicrobial therapy.

CONCLUSIONS

This case demonstrates difficulties associated with clinical and microbiological diagnosis of primary septic meningococcal arthritis. We describe the first successful use of the FilmArray^® MEP assay in detection of N. meningitidis in that context.

Rapid disease course in African Americans with multiple sclerosis

OBJECTIVE

To investigate utility of a Multiple Sclerosis Severity Scale (MSSS)-based classification system for comparing African American (AA) and white American (WA) multiple sclerosis (MS) subpopulations in the New York State Multiple Sclerosis Consortium (NYSMSC) database. MSSS is a frequency-rank algorithm relating MS disability to disease duration in a large, untreated reference population. Design/

METHODS

Distributions of patients in 6 MSSS-based severity grades were calculated for AA and WA registrants.

RESULTS

There were 419 AA and 5,809 WA patients in the NYSMSC, who had EDSS recorded during years 1-30 since symptom onset. Median EDSS was not different in AA and WA (3.5 vs 3.0, p = 0.60), whereas median MSSS in AA was higher than in WA (6.0 vs 4.8, p = 0.001). AA patients were overrepresented in the 2 most severe grades (41.5% vs 29.3% for WA) and underrepresented in the 2 lowest grades (23.4% vs 35.4%; p < 0.001). In multivariable analysis (ordered logistic and median regression), MSSS for AA remained significantly higher than in WA after adjusting for age, gender, disease duration, disease type distribution, and treatment with disease-modifying therapies.

CONCLUSIONS

The 6-tiered MSSS grading system is a powerful tool for comparing rate of disease progression in subpopulations of interest. MSSS-based analysis demonstrates that African ancestry is a risk factor for a more rapidly disabling disease course.

Multiple sclerosis characteristics in African American patients in the New York State Multiple Sclerosis Consortium

The objective of this study was to determine the clinical characteristics of multiple sclerosis (MS) in African American (AA) patients in the New York State Multiple Sclerosis Consortium (NYSMSC) patient registry. The NYSMSC is a group of 18 MS centers throughout New York State organized to prospectively assess clinical characteristics of MS patients. AAs comprise 6% (329) of the total NYSMSC registrants (5602). Demographics, disease course, therapy, and socioeconomic status were compared in AA registrants versus nonAfrican Americans (NAA). There was an increased female preponderance and a significantly younger age at diagnosis in the AA group. AA patients were more likely to have greater disability with increased disease duration. No differences were seen in types of MS and use of disease modifying therapies. Our findings suggest a racial influence in MS. Further genetic studies that consider race differences are warranted to elucidate mechanisms of disease susceptibility.

An in vitro analysis of wrist motion: the effect of limited intercarpal arthrodesis and the contributions of the radiocarpal and midcarpal joints

Radiocarpal and intercarpal arthrodeses were simulated in 12 fresh cadaver wrists by means of external fixation. Range-of-motion measurements were made before and after simulated arthrodesis and used to calculate the contribution of the midcarpal and radiocarpal joints to wrist motion, as well as the residual wrist motion after limited intercarpal arthrodeses. Relative contributions to wrist motion were as follows: wrist flexion: radiocarpal (RC) joint 63%, midcarpal (MC) joint 36%; wrist extension: RC joint 53%, MC joint 46%. The wrist motion remaining after simulated arthrodeses was as follows: capitate-hamate: flexion (Flx) 98%, extension (Ext) 92%, ulnar deviation (UD) 96%, radial deviation (RD) 90%; scaphoid-lunate: Flx 97%, Ext 91%, UD 90%, RD 91%; scaphoid-trapezium-trapezoid: Flx 86%, Ext 88%, UD 67%, RD 69%; scaphoid-lunate-triquetrum: Flx 91%, Ext 82%, UD 86%, RD 70%; capitate-lunate: Flx 70%, Ext 59%, UD 89%, RD 79%; capitate-hamate-triquetrum: Flx 88%, Ext 79%, UD 88%, RD 81%; hamate-triquetrum: Flx 90%, Ext 85%, UD 89%, RD 94%; scaphoid-trapezium-trapezoid-capitate: Flx 85%, Ext 77%, UD 64%, RD 57%.

Selective tarsal arthrodesis: an in vitro analysis of the effect on foot motion

Five different intertarsal arthrodeses were simulated in 15 fresh cadaver feet/ankles utilizing external fixation. Pin placement was verified radiographically. Range of motion measurements were performed before pin placement, after pin placement, and after simulated arthrodesis. The deficit in foot motion created by selected limited intertarsal fusions was then measured. The prearthrodesis range of motion measurements were found to be dorsiflexion (DF), 27 degrees; plantarflexion (PF), 57 degrees; total inversion (INVT), 29 degrees; eversion total (EVT), 22 degrees; hindfoot varus (VRH), 16 degrees; hindfoot valgus (VLH), 12 degrees. The deficits in motion after arthrodesis were as follows. Ankle (tibiotalar): DF, 50.7%; PF, 70.3%; INVT, 8.7%; EVT, 9.4%; VRH, 34.6%; VLH, 27.8%. Hindfoot arthrodesis (Tibiotalar calcaneal): DF, 53%; PF, 71.3%; INVT, 49.5%; EVT, 47.6%, VRH, 100%; VLH, 100%. Pantalar (Tibotalar calcaneal cuboid navicular): DF, 62.8%; PF, 82.2%; INVT, 71.7%; EVT, 67.4%; VRH, 100%; VLH, 100%. Triple (Talocalcaneal cuboid navicular): DF, 12.5%; PF, 15.5%; INVT, 50%; EVT, 51.4%; VRH, 60.5%; VLH, 60.5%. Total tarsal arthrodesis: DF, 78.5%; PF, 90.2%, INVT, 87.5%; EVT, 83.6%; VRH, 100%; VLH, 100%.