Abstract: Objective    To investigate the correlation between clinical features and cellular immunity level in preschool children infected with human metapneumovirus （hMPV）. Methods    A total of 1275 nasopharyngeal swabs were collected for retrospective analysis from  preschool children with respiratory tract infection admitted to our hospital from May 2021 to May 2022. PCR amplification was used to screen hMPV and other common respiratory viruses and bacteria. The epidemiological characteristics，clinical manifestations，laboratory tests and imaging tests and their correlation with the level of T-lymphocyte subsets were analyzed. Results Among 1275 samples，105 samples were positive for hMPV （8.2%），among which 20 cases were hMPV combined with other viruses，and 77 cases were hMPV combined with bacterial infection.The positive rate of hMPV peaked in late spring and early summer. There were 42 females （40.0%） and 63 males （60.0%）. The main clinical features included fever in 86 cases （81.9%），cough in 103 cases （98.1%），wheezing in 47 cases （44.8%），shortness of breath in 27 cases （25.7%），oxygen therapy in 27 cases （25.7%），moist rale in lung in 91 cases （86.7%）；imaging pneumonia： there were 82 cases （78.1%），28 cases （26.7%） with lung consolidation，82 cases （78.1%） with elevated lactate dehydrogenase，CD3+CD4+（38.42±9.17），CD3+CD8+（23.52±6.26），CD3-CD19+（24.54±8.15），CD56+CD16+（7.72±4.74）.In the hMPV group，children receiving oxygen were negatively correlated with CD3+CD4+ （P=0.007）. Conclusion    The main clinical manifestations of preschool children infected with hMPV are cough，fever，and moist rales in the lungs. Some children have wheezing attacks，a small number of children can have cause severe infection，and most children have increased lactate dehydrogenase. The levels of T-lymphocytes subsets show that the proportion of CD3+CD8+，CD56+CD16+ decreases，while proportion of B-lymphocytes increases. In the hMPV group，the level of CD3+，CD3+CD4+，CD3+CD8+，and CD56+CD16+ are negatively correlated with severe infecion in children. 

Key words: human metapneumovirus, preschool child, T-lymphocyte subsets

摘要： 目的    了解学龄前儿童人偏肺病毒（hMPV）感染后的临床特征与细胞免疫水平相关性。方法    回顾性分析2021年5月至2022年5月广西壮族自治区妇幼保健院呼吸道感染的学龄前患儿鼻咽拭子样本1275份，采用PCR扩增筛查hMPV和其他常见呼吸道病毒及细菌，分析学龄前儿童hMPV感染的流行病学特点、临床表现、实验室检查、影像学检查及与T淋巴细胞亚群水平相关性。结果    1275份标本中有105份样本检测hMPV阳性，阳性检出率（8.2%），其中hMPV合并其他病毒20例，hMPV合并细菌感染77例；hMPV阳性率在春末夏初呈现高峰；女性42例（40.0%），男性63例（60.0%）；主要临床特征：发热86例（81.9%），咳嗽103例（98.1%），喘息47例（44.8%），气促27例（25.7%），氧疗27例（25.7%），肺部湿啰音91例（86.7%）；影像学肺炎：82例（78.1%），肺实变28例（26.7%），乳酸脱氢酶升高82例（78.1%），CD3+CD4+ （38.42±9.17），CD3+CD8+（23.52±6.26），CD3-CD19+（24.54±8.15），CD56+CD16+（7.72±4.74）。hMPV组中吸氧的患儿与CD3+CD4+呈负相关（P=0.007）。结论    学龄前儿童感染hMPV后以咳嗽、发热、肺部湿啰音为主要临床表现，部分患儿有喘息发作，少部分可引起重症感染，大部分患儿乳酸脱氢酶可升高，T淋巴细胞以CD3+、CD3+CD8+比例降低，B淋巴细胞比例升高为主，hMPV组中重症感染的患儿与CD3+、CD3+CD4+、CD3+CD8+、CD56+CD16+水平呈负相关。

关键词: 人偏肺病毒, 学龄前儿童, T淋巴细胞亚群