LAUSR

BACKGROUND Atypical lymphocytes (AL), or reactive lymphocyte, exist in peripheral blood when stimulated by viral infection, drugs, inflammatory signals or allergens. Studies have shown that specific changes in peripheral blood (PB) analysis can predict morphological changes in blood cells. The objective of this study was to explore the value of the peripheral blood lymphocyte count in predicting the presence of AL. METHODS One hundred ninety-nine outpatients were selected from Beijing Chao-Yang Hospital, Capital Medical University from January to April 2015 and underwent manual cell classification with evaluation of complete clinical data. The results of manual classification of peripheral blood leukocytes and peripheral blood routine analysis were assessed, and the correlation between peripheral blood lymphocyte counts and presence of atypical lympho-cytes evaluated using receiver operating characteristic (ROC) curves for each subject. RESULTS Peripheral blood lymphocytes ≥ 2.375 x 109/L was found to be the optimal cutoff point for predicting atypical lymphocytes. The area under the curve (AUC), 95% confidence interval (CI), sensitivity and specificity were 0.7984, 0.7121 - 0.8846, 68.42%, and 82.8%, respectively, while the accuracy was moderate. When the proportion of peripheral blood lymphocytes was greater than 35.90%, the AUC, 95% CI, sensitivity, and specificity were 0.8729, 0.8092 - 0.9366, 89.47%, and 76.34%, respectively, while the accuracy was moderate. CONCLUSIONS The peripheral blood lymphocyte count of a patient has good predictive value for the existence of atypical lymphocytes, which is helpful for clinical diagnosis.