We sought to determine the quantitative expression of the high-affinity Fc receptor (CD64) on polymorphonuclear neutrophils (PMNs) in inflammatory and functional conditions of the intestine and investigated its correlation with clinical and biological parameters of inflammation.METHODS:
The quantitative expression of CD64 was determined by fluorescence-activated cell sorting analysis in patients with active or inactive inflammatory bowel disease (IBD,n=76), infectious enterocolitis, lactose and/or fructose intolerance, and healthy subjects.RESULTS:
The quantitative expression of CD64 in patients with active IBD (3,398±3,589 molecules per PMN,n=27) was significantly higher than in healthy subjects (607±265,n=28,P<0.001) or in patients with lactose/fructose intolerance (531±150,n=32,P<0.001). The expression of CD64 correlated significantly with C-reactive protein (CRP, 0.65,P<0.0001), Crohn's disease activity index (CDAI, 0.53,P<0.0001), and colitis activity index (CAI, 0.63,P<0.0001) in patients with IBD. With a cutoff point of 800, CD64 had a sensitivity of 88% and a specificity of 93% in discriminating between lactose/fructose intolerance and active IBD. The quantitative expression of CD64 in patients with infectious enterocolitis (19,190±8,920,n=22) was significantly higher than in patients with active IBD (P<0.001). With a cutoff point of 10,000, CD64 showed a sensitivity of 96% and a specificity of 97% in discriminating between infectious enterocolitis and active IBD.CONCLUSIONS:
CD64 could serve as a valuable tool to discriminate between IBD, infectious enterocolitis, and functional intestinal disorders.