Abstract: Background Tuberculous meningitis (TBM) is a common central nervous system (CNS) infectious disease, and is a serious threat to people's health. Due to its diverse clinical manifestations, especially atypical in infants and young children, it is easy to be misdiagnosed and can lead to high disablility rate and mortality rate. At present, cerebrospinal fluid (CSF) cytology still plays an important role in the etiological diagnosis of CNS infectious diseases. Based on the observation of CSF cytological changes of children with TBM, this study is to further understand the performance and evolution characteristics of this disease, so as to improve the ability of early diagnosis and judgment on the treatment effect. Methods Fresh CSF was collected to make smears by using cytological slide centrifugation, and apply May-Grunwald-Giemsa (MGG) staining for morphological classification. Results CSF cytology of all patients were abnormal. The average leukocyte count of children with TBM was (310.19 ± 156.26)× 10⁶/L, and was significantly different from that of children with purulent meningitis (P = 0.000). Lymphocyte proportion of TBM group was (66.56 ± 14.08)%, and there were significant differences among different groups ( P = 0.037, 0.000). Compared to children with purulent meningitis, higher proportion of monocytes ( P = 0.000, 0.020) and plasma cells ( P = 0.001, 0.004) were found in children with TBM and viral meningitis. The positive detection rate of plasma cells in children with TBM was higher than that in children with purulent meningitis ( P = 0.001). Conclusion The CSF cytology changing characteristics of children with TBM are revealed. In the beginning the lymphocyte proportion is dominant in CSF cytology, and then different extents of mixed cellular response appear as disease develops. For children with effective treatment, the proportion of neutrophils decreases rapidly and turns to lymphocyte reaction gradually, with monocytes and plasma cells, lasting for a long time. Long-term mixed cellular response will happen in children with ineffective treatment. All in all, the CSF cytology changing characteristics are significant in clinical diagnosis and differential diagnosis of TBM in children.

Key words: Tuberculosis, meningeal, Cerebrospinal fluid, Cytology , Child

摘要： 研究背景 结核性脑膜炎是严重威胁生命健康的中枢神经系统感染性疾病，由于临床表现多样化尤其是婴幼儿症状多不典型，故疾病早期容易误诊，并导致较高的病残率和病死率。目前脑脊液细胞学检查对中枢神经系统感染性疾病的病因学诊断仍具有重要价值，本文通过观察结核性脑膜炎患儿脑脊液细胞学变化，进一步深入了解其表现及演变特点，以提高对其早期识别能力及对诊断治疗效果的判断。方法 采集新鲜脑脊液以细胞玻片离心法制片，经迈-格-姬染色进行形态学分类。结果 所有入组病例脑脊液细胞学均有异常。其中结核性脑膜炎组患儿脑脊液白细胞计数平均（310.19 ±156.26 ）× 10⁶/L ，高于化脓性脑膜炎组（P = 0.000）；淋巴细胞比例为（66.56 ± 14.08）% ，低于病毒性脑膜炎组（P = 0.037），但高于化脓性脑膜炎组（P = 0.000）。与化脓性脑膜炎组比较，结核性脑膜炎组和病毒性脑膜炎组单核细胞（P = 0.000，0.020）和浆细胞（P = 0.001，0.004）比例升高，而且结核性脑膜炎组浆细胞阳性检出率显著升高（P = 0.001）。 结论 儿童结核性脑膜炎患儿脑脊液细胞学演变特点为：早期以淋巴细胞比例占优势，随病程进展出现程度不同的混合细胞反应，治疗有效者中性粒细胞比例下降较快，逐渐转化为淋巴细胞反应，伴有单核细胞和浆细胞，并持续较长时间；无效者则长期呈混合细胞反应。脑脊液细胞学演变特点对儿童结核性脑膜炎的诊断和鉴别诊断具有重要临床意义。

关键词: 结核, 脑膜, 脑脊髓液, 细胞学, 儿童