Circulating fibrocyte percentage and neutrophil-lymphocyte ratio are accurate biomarkers of uncomplicated and complicated appendicitis: a prospective cohort study

There is increasing evidence that uncomplicated appendicitis (UA) may be treated nonoperatively in cases of UA. This study aimed to evaluate and compare the diagnostic accuracy of circulating fibrocyte percentage (CFP), white blood cell count, C-reactive protein, and neutrophil-lymphocyte ratio (NLR) in diagnosing uncomplicated and complicated appendicitis. Eighty consecutive adult patients presenting with suspected appendicitis were recruited in a cohort-based prospective study between June 2015 and February 2016 at University Hospital Limerick in Ireland. Peripheral venous samples were obtained at the presentation. Clinical, biochemical, radiological, and histopathological parameters were recorded. The CFP was determined by dual-staining for CD45 and collagen-I using flow cytometry analysis and correlated with histopathological diagnoses. Of the 46 patients who underwent appendicectomy, 34 (73.9%) had histologically proven acute appendicitis. A comparison of the diagnostic accuracy of biomarkers demonstrated the CFP had the highest diagnostic accuracy for UA (area under the curve=0.83, sensitivity=72.7%, specificity=83.3%, P=0.002). The NLR had the highest diagnostic accuracy in relation to complicated appendicitis (area under the curve=0.84, sensitivity=75.5%, specificity=83.3%, P=0.005). CFP and NLR are accurate biomarkers of UA and complicated appendicitis.