摘要目的:探讨合并基础疾病的儿童感染新型冠状病毒Omicron变异株BA.2.2后的临床特征。方法:回顾性分析2022年3月2日至6月10日上海交通大学医学院附属上海儿童医学中心收治的76例确诊新型冠状病毒感染且合并基础疾病患儿的临床表现、辅助检查、治疗及预后等。按合并疾病种类分为血液肿瘤组、非血液肿瘤组，非血液肿瘤组患儿包括心肺疾病组、神经系统疾病组、先天性畸形组，分析不同种类基础疾病患儿感染新型冠状病毒Omicron变异株后的临床特征及预后。结果:76例合并基础疾病儿童中，初诊发热者61例、无症状者15例，合并血液肿瘤疾病、心肺疾病、神经系统疾病、先天性畸形患儿分别为26例、22例、20例、8例；4种基础疾病患儿发热时间3~7 d，合并咳嗽、鼻塞、流涕、呕吐、腹泻等表现较少，肺部影像学表现轻，无一例重症肺炎发生，各疾病组临床表现无明显差异( P>0.05)。血液肿瘤组患儿更易发生单脏器或多脏器功能不全，C-反应蛋白水平较非血液肿瘤组升高，白细胞计数、中性粒细胞计数、淋巴细胞计数、血红蛋白较非血液肿瘤组降低，病毒转阴时间、发热持续时间高于非血液肿瘤组，差异均有统计学意义( P均<0.05)。血液肿瘤组患儿中，2周内进行化疗感染新型冠状病毒后的患儿血象、炎症指标较非化疗组更差，发热持续时间、病毒转阴时间更长( P<0.05)，其中3例血液肿瘤患儿病毒转阴后，在进行化疗及手术治疗后出现复阳。 结论:新型冠状病毒Omicron变异株BA.2.2对合并心肺疾病、神经系统疾病、先天性畸形患儿未造成严重影响，但可导致血液肿瘤患儿发热持续时间及病毒转阴时间延长，其中化疗后患儿较未化疗患儿所受影响更大，这对血液肿瘤患儿疫情防控策略制定及化疗时机选择产生重要影响。

abstractsObjective:To investigate the clinical characteristics of SARS-CoV-2 Omicron variant BA.2.2 infection in children with different basic diseases.Methods:A total of 76 children with different basic diseases admitted to Shanghai Children′s Medical Center, Shanghai Jiao Tong University School of Medicine from March 2 to June 10, 2022 were retrospectively analyzed in terms of clinical manifestations, supplementary examination, treatment and prognosis.These children were divided into hematologic tumor group and non-hematologic tumor group which included cardiopulmonary disease group, neurological disease group and congenital malformation group.The clinical characteristics and prognosis of SARS-CoV-2 Omicron variant infection in children with basic diseases were analyzed.Results:Among 76 children with basic diseases, 61 patients were newly diagnosed with fever and 15 patients were asymptomatic.There were 26, 22, 20, and 8 cases with hematologic tumor diseases, cardiopulmonary diseases, neurological diseases and congenital malformation, respectively.The average fever time was 3-7 days.There was no significant difference in the clinical manifestations among each group ( P>0.05). However, children with hematological tumors were more prone to single organ or multiple organ dysfunction.The level of C-reactive protein was higher than that in the non-hematologic tumor group, while the white blood cell count, neutrophil count, lymphocyte count and hemoglobin were lower than those in the non-hematologic tumor group.The time of virus negative transformation and the duration of fever were higher than those in the non-hematologic tumor group, with statistical significance ( P<0.05). Among the children in the hematologic tumor group, the blood routine and inflammation indexes of children infected with SARS-CoV-2 after chemotherapy within 2 weeks were worse than those in the non-chemotherapy group, and the duration of fever and the time of virus negative transformation were significantly longer ( P<0.05). Three children with hematologic tumor showed virus positive recovery after chemotherapy and surgical treatment after virus negative transformation. Conclusion:Omicron variant BA.2.2 of SARS-CoV-2 has no serious impact on children with cardiopulmonary diseases, nervous system diseases and congenital malformations.However, the duration of fever and virus positive time in hematologic tumor group extended, especially after chemotherapy.It has an important impact on the formulation of epidemic prevention and timing selection of chemotherapy for children with hematological tumors.