Centre for Infectious Diseases and Microbiology, Westmead Hospital and the University of Sydney, Westmead, NSW, Australia.
Curr Opin Infect Dis. 2010 Dec;23(6):567-77. doi: 10.1097/QCO.0b013e32833ef7d1.
Prompt diagnosis of infection in febrile neutropenia hosts with hematological malignancy is essential in directing therapy. We highlight experience using modern molecular and biomarker-based methods to diagnose bacterial and fungal bloodstream infections and invasive aspergillosis in these patients.
Nucleic acid amplification-based strategies are used to detect and identify pathogens from blood cultures or from blood/clinical specimens; the latter are more likely to influence clinical management. Advances in DNA extraction include standardization of isolation of Aspergillus DNA from blood. Broad-range and/or multiplex PCR generally have greater clinical utility than pathogen-specific assays. However, Aspergillus-PCR assays are useful in confirming/excluding disease and monitoring high-risk patients for invasive aspergillosis. Commercial real-time PCR/peptide nucleic acid fluorescent in-situ hybridization systems, used as adjuncts to blood cultures, to detect bacteria and fungi in blood cultures (or blood), are as sensitive as culture and enable earlier institution of targeted therapy. Yet there are no data indicating that molecular detection of bacterial/fungal pathogens influences patient outcomes. Positive serum Aspergillus galactomannan and 1,3-β-D-glucan tests are useful biomarkers in the diagnosis/screening of fungal infection, and have potential as measures of response to antifungal therapy. Serum procalcitonin levels can help differentiate infectious, from noninfectious, fever. Combined molecular and nonmolecular testing likely offers optimal diagnostic accuracy.
Numerous PCR-based and biomarker tools are available for the diagnosis and screening of infection in febrile neutropenia hosts. The optimal approach remains to be resolved by prospective studies examining the impact of one or more of tests on patient outcomes.
在血液病患者中,发热伴中性粒细胞减少症患者的感染应及时诊断,这对指导治疗至关重要。我们强调了使用现代分子和基于生物标志物的方法来诊断这些患者的细菌和真菌血流感染以及侵袭性曲霉病的经验。
基于核酸扩增的策略用于从血培养物或血液/临床标本中检测和鉴定病原体;后者更有可能影响临床管理。DNA 提取技术的进步包括从血液中分离曲霉属 DNA 的标准化。广泛或多重 PCR 通常比病原体特异性检测更具临床实用性。然而,曲霉属-PCR 检测有助于确诊/排除疾病,并监测高危侵袭性曲霉病患者。商业实时 PCR/肽核酸荧光原位杂交系统,作为血培养的辅助手段,可用于检测血液培养物(或血液)中的细菌和真菌,与培养一样敏感,并能更早地进行靶向治疗。然而,目前尚无数据表明细菌/真菌病原体的分子检测会影响患者的预后。血清曲霉属半乳甘露聚糖和 1,3-β-D-葡聚糖检测是真菌感染诊断/筛查的有用生物标志物,并且有作为抗真菌治疗反应的衡量指标的潜力。血清降钙素原水平有助于区分感染性和非感染性发热。联合分子和非分子检测可能提供最佳的诊断准确性。
有许多基于 PCR 和生物标志物的工具可用于发热伴中性粒细胞减少症患者的感染诊断和筛查。通过前瞻性研究来评估一种或多种检测方法对患者结局的影响,可能会确定最佳的方法。