Table 1_Characteristics of T-lymphocyte subsets in patients with severe fever with thrombocytopenia syndrome complicated with invasive pulmonary aspergillosis: a retrospective study.docx

ObjectivesImmunosuppressed patients often acquire invasive pulmonary aspergillosis (IPA). In recent years, the incidence of patients with severe fever with thrombocytopenia syndrome (SFTS) complicated with IPA has increased. This study aimed to investigate the characteristics of the counts of T-lymphocyte subsets in patients with SFTS combined with IPA and explore their predictive value for IPA infection in SFTS patients.
MethodsWe conducted a retrospective review of all patients with SFTS admitted to Nanjing Drum Tower Hospital between January 2016 and August 2022. The patients were divided into IPA and the non-IPA group. Clinical symptoms, laboratory findings, comorbidities, and overall prognosis were collected. Transcriptome sequencing was performed on six of the samples.
ResultsA total of 99 SFTS patients were included, of whom 21 (21.2%) developed IPA. The 28-day mortality rate (33.3%) was higher in the IPA group than in the non-IPA group. The IPA group had a significant decrease in the absolute counts of total lymphocytes and CD4+ T lymphocytes and an increase in the ratio of CD4/CD8 T lymphocytes. ROC curves showed that the sensitivity and specificity for predicting the occurrence of IPA in SFTS patients was 50% and 95%, respectively, when the cut-off value for CD4+ T lymphocytes was 386 cells/μL. The transcriptome analysis revealed significant differences in host gene expression profiles between IPA and non-IPA groups, with notable enrichment in KEGG pathways related to metabolism, cellular functions, and systemic processes.
ConclusionsPatients with an absolute count of CD4+ lymphocytes below 386 cells/μL are at risk of acquiring secondary IPA. It is necessary to screen the counts of T-lymphocyte subsets in SFTS patients after admission.

研究目的：免疫抑制患者常罹患侵袭性肺曲霉病（invasive pulmonary aspergillosis, IPA）。近年来，发热伴血小板减少综合征（severe fever with thrombocytopenia syndrome, SFTS）患者合并IPA的发病率呈上升趋势。本研究旨在探讨SFTS合并IPA患者的T淋巴细胞亚群计数特征，并探究其对SFTS患者继发IPA感染的预测价值。
研究方法：本研究对2016年1月至2022年8月期间南京鼓楼医院收治的所有SFTS患者进行回顾性分析。将入组患者分为IPA组与非IPA组，收集其临床症状、实验室检查结果、合并症及总体预后情况。对其中6份样本开展转录组测序（transcriptome sequencing）。
研究结果：本研究共纳入99例SFTS患者，其中21例（21.2%）继发IPA。IPA组的28天死亡率（33.3%）显著高于非IPA组。IPA组患者的总淋巴细胞及CD4+T淋巴细胞绝对计数均显著降低，而CD4/CD8 T淋巴细胞比值升高。受试者工作特征曲线（ROC curves）分析显示，当CD4+T淋巴细胞绝对计数的截断值为386个/μL时，其预测SFTS患者发生IPA的灵敏度与特异度分别为50%与95%。转录组分析结果显示，IPA组与非IPA组患者的宿主基因表达谱存在显著差异，且差异基因在代谢、细胞功能及全身进程相关的KEGG通路（KEGG pathways）中显著富集。
研究结论：CD4+T淋巴细胞绝对计数低于386个/μL的SFTS患者具备继发IPA的风险，因此对入院后的SFTS患者进行T淋巴细胞亚群计数筛查具有必要性。