The Pediatric Crohn Disease Morbidity Index (PCD-MI): Development of a Tool to Assess Long-Term Disease Burden Using a Data-Driven Approach.

BACKGROUND/OBJECTIVE: Heterogeneity and chronicity of Crohn disease (CD) make prediction of outcomes difficult. To date, no longitudinal measure can quantify burden over a patient's disease course, preventing assessment and integration into predictive modeling. Here, we aimed to demonstrate the feasibility of constructing a data driven, longitudinal disease burden score. METHODS: Literature was reviewed for tools used in assessment of CD activity. Themes were identified to construct a pediatric CD morbidity index (PCD-MI). Scores were assigned to variables. Data were extracted automatically from the electronic patient records at Southampton Children's Hospital, diagnosed from 2012 to 2019 (inclusive). PCD-MI scores were calculated, adjusted for duration of follow up and assessed for variation (ANOVA) and distribution (Kolmogorov-Smirnov). RESULTS: Nineteen clinical/biological features across five themes were included in the PCD-MI including blood/fecal/radiological/endoscopic results, medication usage, surgery, growth parameters, and extraintestinal manifestations. Maximal score was 100 after accounting for follow-up duration. PCD-MI was assessed in 66 patients, mean age 12.5 years. Following quality filtering, 9528 blood/fecal test results and 1309 growth measures were included. Mean PCD-MI score was 14.95 (range 2.2-32.5); data were normally distributed ( P = 0.2) with 25% of patients having a PCD-MI < 10. There was no difference in the mean PCD-MI when split by year of diagnosis, F -statistic 1.625, P = 0.147. CONCLUSIONS: PCD-MI is a calculatable measure for a cohort of patients diagnosed over an 8-year period, integrating a wide-range of data with potential to determine high or low disease burden. Future iterations of the PCD-MI require refinement of included features, optimized scores, and validation on external cohorts.

Emergency Department point-of-care antiviral host response testing is accurate during periods of multiple respiratory virus co-circulation.

OBJECTIVES: FebriDx is a CE-marked, FDA-approved point-of-care test that detects the antiviral host response protein Myxovirus Resistance Protein A (MxA), in addition to C-reactive protein, using finger-prick blood. FebriDx MxA detection had a high negative predictive value for COVID-19 in symptomatic adults presenting to hospital in the first waves of the pandemic and was used subsequently as a 'rule out' triage tool in Emergency departments. The diagnostic accuracy of FebriDx MxA in the current context of co-circulation of influenza, SARS-CoV-2, and Respiratory Syncytial Virus (RSV), and in the era of COVID-19 vaccination, is unknown. METHODS: We retrospectively evaluated the diagnostic performance of FebriDx MxA in adults with acute respiratory symptoms presenting to the Emergency Department (ED) of a large UK teaching hospital using Reverse Transcription Polymerase Chain Reaction (RT-PCR) as the reference standard (Cepheid Xpert Xpress SARS-CoV-2/Flu/RSV). RESULTS: Between March 9th 2022 and March 8th 2023, 5426 patients had both FebriDx and RT-PCR testing with valid results. 999 (18.4%) of patients had influenza detected, 520 (9.6%) SARS-CoV-2, and 190 (3.5%) RSV. Negative Predictive Value (NPV) of MxA detection by FebriDx was 97.5% (96.9-98.0) for influenza, 97.1% (96.4-97.7) for SARS-CoV-2, 98.1% (97.5-98.6) for RSV, and 92.8% (91.8-93.7) for all viruses combined. CONCLUSIONS: In symptomatic adults, FebriDx MxA had a high NPV for influenza and RSV, and retained a high NPV for SARS-CoV-2, in the context of virus co-circulation and widespread COVID-19 vaccination. FebriDx continues to be a useful 'rule out' triage tool in the ED and could potentially be scaled to provide a national triage solution for future viral pandemics.