METHODS: We prospectively enrolled two cohorts of patients undergoing intensive myelosuppressive or immunosuppressive treatments at high risk for IA. ELISpot was performed to detect Aspergillus-specific T cells producing Interleukin-10.
RESULTS: In the discovery cohort, a derived cut-off of 40 spot forming cells (SFCs)/106 PBMCs has shown to correctly classify IA cases with a sensitivity and specificity of 89.5% and 88.6%, respectively. This cut-off is lowered to 25 SFC when considering the subset of possible IA patients, with sensitivity and specificity of 76% and 93%, respectively. The application of the 40 SFCs cut-off to the validation cohort resulted in a positivity rate of 83.3% in proven/probable cases and a negativity rate of 92.5% in possible/non-IA cases. Adopting the 25 SCFs cut-off, the assay resulted positive in 83.3% of proven/probable cases while it resulted negative in 66.7% of possible/non-IA cases.
CONCLUSIONS: ELISpot shows promises in the diagnosis of IA and the possibility to use two distinct cut-offs with similar diagnostic performances according to patients\' different pre-test probability of infection can widen its use in patients at risk.
方法:我们前瞻性招募了两组接受强化骨髓抑制或免疫抑制治疗的IA高危患者。进行ELISpot以检测产生白细胞介素-10的曲霉特异性T细胞。
结果:在发现队列中,40个斑点形成细胞(SFCs)/106个PBMC的衍生截断值已显示出正确分类IA病例的敏感性和特异性分别为89.5%和88.6%,分别。当考虑到可能的IA患者的子集时,此截止值会降低到25SFC,敏感性和特异性分别为76%和93%,分别。将40个SFCs截止值应用于验证队列,在已证实/可能病例中的阳性率为83.3%,在可能/非IA病例中的阳性率为92.5%。采用25个SCF截止值,该检测在83.3%的已证实/可能病例中结果为阳性,而在66.7%的可能/非IA病例中结果为阴性.
结论:ELISpot在IA的诊断中显示出希望,并且可以根据患者使用具有相似诊断性能的两个不同的截止值\“不同的感染前测试概率可以扩大其在有风险的患者中的使用范围。