The clinical value of high fluorescent lymphocytes and smudge cells in the diagnosis of infectious mononucleosis

BACKGROUND: The diagnostic value of high fluorescent lymphocytes (HFLC) and smudge cells in diseases like sepsis has been confirmed. In this study, we explore the diagnostic value of HFLC and smudge cells for infectious mononucleosis (IM). METHODS: Sixty‐two IM patients, 67 healthy controls, 84 patients with upper respiratory tract virus infection, and 35 patients with malignant lymphoid diseases were enrolled. The complete blood counts and leukocyte differential counts are tested, and the smudge cells were manually counted. RESULTS: The value of HFLC% and smudge cells of the IM group were significantly higher than those of healthy controls and disease controls (p < 0.05), and the HFLC% value of IM patients was positively correlated with the number of reactive lymphocytes (r = 0.265). When the cutoff value of HFLC% was 0.4%, and the diagnostic value of IM was high (AUC = 0.995). When the smudge cells >2/100 nucleated cells, it can show better (AUC = 1.000). When the cutoff value of the HFLC% was 1.2%, it can effectively distinguish IM patients from upper respiratory tract virus infection patients (AUC = 0.934); when smudge cells >16/100 nucleated cells, it also has high differential diagnosis value (AUC = 0.913). In addition, the AUC of the combination HFLC% and smudge cells for the differential diagnosis can be increased to 0.968. The performance value of single HFLC% (AUC = 0.942) for distinguishing IM from malignant lymphoid diseases was better than smudge cells and combine index with the cutoff value of 0.4%. CONCLUSION: HFLC% and smudge cells can be used as effective indicators in the early diagnosis and differential diagnosis of IM.