Mahidol-Oxford Tropical Medicine Research Unit, Mahidol University, Bangkok, Thailand.
Centre for Tropical Medicine and Global Health, University of Oxford, Oxford, UK.
Trop Med Int Health. 2020 Mar;25(3):291-300. doi: 10.1111/tmi.13358. Epub 2020 Jan 6.
Identifying febrile patients requiring antibacterial treatment is challenging, particularly in low-resource settings. In South-East Asia, C-reactive protein (CRP) has been demonstrated to be highly sensitive and moderately specific in detecting bacterial infections and to safely reduce unnecessary antibacterial prescriptions in primary care. As evidence is scant in sub-Saharan Africa, we assessed the sensitivity of CRP in identifying serious bacterial infections in Tanzania.
Samples were obtained from inpatients and outpatients in a prospective febrile illness study at two hospitals in Moshi, Tanzania, 2011-2014. Bacterial bloodstream infections (BSI) were established by blood culture, and bacterial zoonotic infections were defined by ≥4 fold rise in antibody titre between acute and convalescent sera. The sensitivity of CRP in identifying bacterial infections was estimated using thresholds of 10, 20 and 40 mg/l. Specificity was not assessed because determining false-positive CRP results was limited by the lack of diagnostic testing to confirm non-bacterial aetiologies and because ascertaining true-negative cases was limited by the imperfect sensitivity of the diagnostic tests used to identify bacterial infections.
Among 235 febrile outpatients and 569 febrile inpatients evaluated, 31 (3.9%) had a bacterial BSI and 61 (7.6%) had a bacterial zoonosis. Median (interquartile range) CRP values were 173 (80-315) mg/l in bacterial BSI, and 108 (31-208) mg/l in bacterial zoonoses. The sensitivity (95% confidence intervals) of CRP was 97% (83%-99%), 94% (79%-98%) and 90% (74%-97%) for identifying bacterial BSI, and 87% (76%-93%), 82% (71%-90%) and 72% (60%-82%) for bacterial zoonoses, using thresholds of 10, 20 and 40 mg/l, respectively.
C-reactive protein was moderately sensitive for bacterial zoonoses and highly sensitive for identifying BSIs. Based on these results, operational studies are warranted to assess the safety and clinical utility of CRP for the management of non-malaria febrile illness at first-level health facilities in sub-Saharan Africa.
在资源匮乏的环境中，识别需要接受抗菌治疗的发热患者具有一定挑战性。在东南亚，C 反应蛋白（CRP）在检测细菌感染方面具有高敏感性和中等特异性，并能安全减少初级保健中不必要的抗菌药物处方。由于撒哈拉以南非洲地区的证据较少，我们评估了 CRP 在坦桑尼亚识别严重细菌感染的敏感性。
2011-2014 年，在坦桑尼亚莫希的两家医院进行了一项前瞻性发热疾病研究，从住院和门诊患者中采集样本。通过血培养确定细菌性血流感染（BSI），通过急性和恢复期血清抗体滴度升高≥4 倍确定细菌性人畜共患病感染。使用 10、20 和 40 mg/L 的 CRP 阈值来估计 CRP 识别细菌感染的敏感性。由于缺乏诊断性检测来确定非细菌病因的假阳性 CRP 结果，并且由于用于识别细菌感染的诊断性检测的不完善敏感性限制了真阴性病例的确定，因此特异性未进行评估。
在评估的 235 例门诊发热患者和 569 例住院发热患者中，31 例（3.9%）患有细菌性 BSI，61 例（7.6%）患有细菌性人畜共患病。细菌性 BSI 患者 CRP 的中位数（四分位距）为 173（80-315）mg/L，细菌性人畜共患病患者 CRP 的中位数（四分位距）为 108（31-208）mg/L。CRP 的敏感性（95%置信区间）分别为 97%（83%-99%）、94%（79%-98%）和 90%（74%-97%），用于识别细菌性 BSI 的阈值分别为 10、20 和 40 mg/L，87%（76%-93%）、82%（71%-90%）和 72%（60%-82%），用于识别细菌性人畜共患病。
CRP 对细菌性人畜共患病具有中等敏感性，对识别 BSI 具有高度敏感性。基于这些结果，有必要在撒哈拉以南非洲的一级卫生设施中进行关于 CRP 管理非疟疾发热疾病的安全性和临床实用性的操作性研究。
