UW Health, Madison, Wisconsin, USA.
University of Wisconsin-Madison, School of Medicine and Public Health, Department of Medicine, Infectious Disease Division, Madison, Wisconsin, USA.
Microbiol Spectr. 2022 Dec 21;10(6):e0402222. doi: 10.1128/spectrum.04022-22. Epub 2022 Nov 10.
This study evaluated the performance and clinical utility of performing intravascular catheter tip cultures (CTC). A retrospective chart review was conducted over a 2.5 year period on all patients who demonstrated growth of at least one organism on CTC. There were a total of 391 CTC performed. 88 (23%) grew at least one organism, while 303 (77%) had no growth. Of the positive CTC, 81 (92%) had blood cultures (BC) collected within 14 days, whereas 7 (8%) did not. Of the positive CTC with BC, 67 (83%) were BC-positive, whereas 14 (17%) were negative. For cases with growth on both CTC and BC, the organisms identified were concordant for 46 (69%) cases and discordant for 21 (31%). Of the concordant cases, 43 (93%) were clinically considered to be bacterial bloodstream infections that were secondary to a catheter infection. For all of the positive CTC cases total, there was no change in the antibiotics or management, with the exceptions of 2 out of 88 (2%) cases. Catheters were removed and cultured for an average of 38.6 h (range: -98 to 288 h) after positive BC results were available. Most CTC are negative, and for the CTC that are positive, most are concordant with BC results. CTC results are generally only available several days after positive BC results are known. The CTC results did not alter the antibiotic therapy or management, with the exceptions of rare cases. As such, this study concludes that CTC do not contribute diagnostic or therapeutic value. Therefore, current guidelines by the Infectious Diseases Society of America on catheter-related bloodstream infection diagnosis should be revised to exclude CTC collection. In patients with intravascular catheters who are febrile or have positive blood cultures and no other obvious sources of infection, catheter tip cultures are often obtained to evaluate potential catheter-related bloodstream infections. However, previous studies reported that the management of catheter-related bloodstream infection cases is entirely based on blood culture growth and susceptibilities and that catheter tip cultures have low diagnostic positive predictive value. Our study represents the largest contemporary evaluation that includes chart reviews on all positive catheter tip culture cases. We found that positive cultures led to no changes in antibiotics or management, except for in two cases. Furthermore, 92% of positive catheter tip cultures were associated with blood culture collections, and catheter cultures were generally available only several days after the blood culture results were known. Thus, our study supports the claim that positive catheter tip cultures add limited diagnostic and therapeutic value in suspected catheter-related bloodstream infections.
本研究评估了进行血管内导管尖端培养（CTC）的性能和临床实用性。对所有至少有一种生物体在 CTC 中生长的患者进行了为期 2.5 年的回顾性图表审查。共进行了 391 次 CTC。88 次（23%）至少有一次生长，而 303 次（77%）没有生长。在阳性 CTC 中，81 次（92%）在 14 天内采集了血培养（BC），而 7 次（8%）没有采集。在有阳性 CTC 和 BC 的情况下，67 次（83%）BC 阳性，14 次（17%）BC 阴性。对于 CTC 和 BC 均生长的病例，46 例（69%）的病原体鉴定结果一致，21 例（31%）不一致。在一致的病例中，43 例（93%）被临床认为是继发于导管感染的细菌性血流感染。对于所有阳性 CTC 病例，除 2 例（2%）外，抗生素或管理均未改变。在获得阳性 BC 结果后，平均 38.6 小时（范围：-98 至 288 小时）取出导管并进行培养。大多数 CTC 为阴性，而对于阳性 CTC，大多数与 BC 结果一致。通常在获得阳性 BC 结果后的几天内才能获得 CTC 结果。除了少数罕见情况外，CTC 结果并未改变抗生素治疗或管理。因此，本研究得出结论，CTC 没有提供诊断或治疗价值。因此，应修订美国传染病学会关于导管相关性血流感染诊断的指南，以排除 CTC 采集。对于发热或血培养阳性且无其他明显感染源的血管内导管患者，常进行导管尖端培养以评估潜在的导管相关性血流感染。然而，先前的研究报告称，导管相关性血流感染病例的处理完全基于血培养的生长和药敏性，导管尖端培养的阳性预测值较低。我们的研究代表了对所有阳性导管尖端培养病例进行图表回顾的最大的当代评估。我们发现，除了两例外，阳性培养并没有改变抗生素或管理。此外，92%的阳性导管尖端培养与血培养采集有关，而导管培养通常在血培养结果已知后的几天内才有。因此，我们的研究支持这样的观点，即阳性导管尖端培养在疑似导管相关性血流感染中增加了有限的诊断和治疗价值。
