A plasma protein biomarker signature that differentiates acute rheumatic fever from related clinical presentations

Acute Rheumatic Fever (ARF) is a systemic inflammatory condition triggered by Group A Streptococcus infection, with timely diagnosis critical to prevent Rheumatic Heart Disease. ARF pathogenesis is poorly understood and diagnosis is based on clinical criteria. Here, we compared ARF cases and well-defined controls from two Uganda cohorts. We identified a 5-protein signature that discriminates ARF patients from clinically-similar conditions (receiver operating characteristic-area under the curve (ROC-AUC)=1.0, n=18 definite ARF vs n=9 known alternate diagnosis; ROC-AUC=0.97, n=18 definite ARF vs n=13 unknown alternate diagnosis), which retained very good diagnostic value in a validation cohort (ROC-AUC=0.83 n=26 definite ARF vs n=13 unknown alternate diagnosis). Pathway analysis identified the epithelial-mesenchymal transition pathway as highly-associated with acute ARF, suggesting that tissue damage and repair is central to ARF pathogenesis. Our findings require further validation, yet highlight the potential for proteomics to identify clinically useful diagnostic biomarkers that would revolutionise ARF diagnosis and treatment.