目的 探讨外周血涂片裂隙淋巴细胞对辅助早期诊断百日咳的意义。方法 采集107例疑似百日咳患儿的鼻咽拭子和外周血。采用PCR-流式荧光杂交法进行百日咳杆菌核酸检测，根据结果分为百日咳组（n=52）和非百日咳组（n=55）；百日咳组按年龄分为<1岁组（n=42）和≥1岁组（n=10），按病情严重程度分为轻症组（n=45）和重症组（n=7）。采用全自动血细胞分析仪对各组患儿进行外周血细胞计数测定，血涂片后行瑞氏染色和过氧化物酶染色，显微镜下观察各组患儿裂隙淋巴细胞并计数。结果 裂隙淋巴细胞呈圆形，胞体较小，胞浆量少，胞核上有切迹或裂缝；过氧化物酶染色为阴性，细胞学分类属淋巴细胞。百日咳组患儿白细胞计数、淋巴细胞比例、血小板计数、裂隙淋巴细胞比例均明显高于非百日咳组（P < 0.001）。百日咳组患儿中，<1岁组患儿淋巴细胞比例、血小板计数、裂隙淋巴细胞比例均明显高于≥1岁组患儿（P < 0.05）；重症组患儿上述血细胞计数及细胞比例均高于轻症组，但差异无统计学意义（P > 0.05）。结论 裂隙淋巴细胞联合外周血细胞计数可为百日咳患儿的早期诊断提供新思路。

Objective To study the value of cleaved lymphocytes in peripheral blood smear in assisting the early diagnosis of pertussis. Methods Nasopharyngeal swabs and peripheral blood samples were collected from 107 children with pertussis-like disease. PCR-flow fluorescent hybridization was used to detect the nucleic acids of Bordetella pertussis. Based on the detection results, the children were divided into two groups:pertussis (n=52) and non-pertussis (n=55). According to age, the pertussis group was divided into two subgroups:<1 year old (n=42) and ≥ 1 year old (n=10). According to disease severity, the pertussis group was divided into another two subgroups:mild (n=45) and severe (n=7). An automatic blood cell analyzer was used to determine peripheral blood cell counts. Wright's staining and peroxidase staining were used to observe and count cleaved lymphocytes under a microscope. Results Cleaved lymphocytes in peripheral blood were round with small cytoplast, less cytoplasm and cleaved or lobulated nuclei. According to the negative peroxidase staining results, these cells were confirmed as lymphocytes. Compared with the non-pertussis group, the pertussis group had significantly higher leukocyte count, lymphocyte percentage, platelet count, and percentage of cleaved lymphocytes (P < 0.001). For the children with pertussis, the <1 year old subgroup had significantly higher lymphocyte percentage, platelet count, and percentage of cleaved lymphocytes than the ≥ 1 year old subgroup (P < 0.05). The severe subgroup had slightly higher leukocyte count, lymphocyte percentage, platelet count, and percentage of cleaved lymphocytes than the mild subgroup (P > 0.05). Conclusions The detection of cleaved lymphocytes combined with peripheral blood cell counts provides a new option for the early diagnosis of pertussis in children.