Mwaturura Tinashe, Olaru Ioana D, Chimhini Gwendoline, Bwakura-Dangarembizi Mutsa, Mangiza Marcia, Chimhuya Simbarashe, Sado Belinda, Katunga Jackie, Tarupiwa Andrew, Juru Agnes, Mashe Tapfumaneyi, Pasi Christopher, Chuchu Veronicah, Gansallo Seyi, Gleeson Birgitta, Fitzgerald Felicity, Ferreyra Cecilia, Kranzer Katharina
The Health Research Unit, Biomedical Research and Training Institute, Harare, Zimbabwe.
Clinical Research Department, London School of Hygiene and Tropical Medicine, London, United Kingdom.
PLOS Glob Public Health. 2025 Apr 9;5(4):e0004343. doi: 10.1371/journal.pgph.0004343. eCollection 2025.
Sepsis is a major cause of mortality in low-resource settings. Effective microbiological culture services are a bottleneck in diagnosis and surveillance.
We aimed to evaluate the performance of the BIOFIRE FILMARRAY Blood Culture Identification 2 (BCID2, bioMérieux) assay in a low-resource setting laboratory in comparison to standard practice.
This five month prospective validation study included all positive blood cultures collected at Sally Mugabe Central Hospital, Harare, Zimbabwe. BCID2 testing was done in parallel to standard phenotypic procedures and resistance testing. Reference identification was performed using mass spectrometry or whole genome sequencing. Only samples with available reference standard results were included in the analysis. Data captured on paper-based forms was entered into electronic case report forms (ODK Collect). Specificity and sensitivity for BCID2 were calculated in comparison to the reference standards, with performance measures calculated using the Wilson score. Biomedical scientists using BCID2 completed a system usability survey (SUS).
Positive results were recorded in 780/2,023 (38.5%) blood cultures, within which 377 (48.3%) had reference results and so were included in analysis. Neonatal samples were most frequent (182, 48.3%), then paediatric (150, 39.8%), then adults (18, 4.8%) and unknown (27, 7.2%). Specificity exceeded 95% throughout. Sensitivity ranged from 50% (A. calcoaceticus-baumanii complex, Proteus spp.) to 100% (S. pneumoniae, Salmonella spp). Using BCID2, CTX-M was detected in 111/175 (74.5%) Enterobacterales, from which 5/111 also had NDM and VIM detected. NDM-5 was detected in 2/5 NDM samples using sequencing. In total 3/23 S. aureus isolates were methicillin resistant, from which one was confirmed using phenotypic antimicrobial susceptibility testing. Usability was good (SUS score = 79.5).
Rapid molecular tests have potential to improve turn-around time and quality of sepsis diagnostics. However, specific work-flows are critical to supplement molecular tests with minimal phenotypic tests for optimal clinical decision-making.
脓毒症是资源匮乏地区死亡的主要原因。有效的微生物培养服务是诊断和监测的瓶颈。
我们旨在评估BIOFIRE FILMARRAY血培养鉴定2（BCID2，生物梅里埃公司）检测方法在资源匮乏地区实验室与标准方法相比的性能。
这项为期五个月的前瞻性验证研究纳入了在津巴布韦哈拉雷的萨利·穆加贝中心医院采集的所有阳性血培养样本。BCID2检测与标准表型程序和耐药性检测同时进行。使用质谱法或全基因组测序进行参考鉴定。分析仅纳入有可用参考标准结果的样本。纸质表格记录的数据录入电子病例报告表格（ODK Collect）。与参考标准相比计算BCID2的特异性和敏感性，使用威尔逊评分计算性能指标。使用BCID2的生物医学科学家完成了系统可用性调查（SUS）。
2023份血培养样本中有780份（38.5%）呈阳性结果，其中377份（48.3%）有参考结果，因此纳入分析。新生儿样本最常见（182份，48.3%），其次是儿科样本（150份，39.8%），然后是成人样本（18份，4.8%）和身份不明样本（27份，7.2%）。特异性始终超过95%。敏感性范围为50%（醋酸钙不动杆菌-鲍曼不动杆菌复合体、变形杆菌属）至100%（肺炎链球菌、沙门菌属）。使用BCID2，在175份肠杆菌科细菌中有111份（74.5%）检测到CTX-M，其中5/111还检测到NDM和VIM。使用测序在5份NDM样本中的2份检测到NDM-5。总共23份金黄色葡萄球菌分离株中有3份对甲氧西林耐药，其中1份通过表型抗菌药物敏感性检测得到确认。可用性良好（SUS评分为79.5）。
快速分子检测有潜力缩短脓毒症诊断的周转时间并提高诊断质量。然而，特定的工作流程对于以最少的表型检测补充分子检测以实现最佳临床决策至关重要。
