Bacha Jason M, Ngo Katherine, Clowes Petra, Draper Heather R, Ntinginya Elias N, DiNardo Andrew, Mangu Chacha, Sabi Issa, Mtafya Bariki, Mandalakas Anna M
Baylor College of Medicine Children's Foundation - Tanzania, Centre of Excellence at Mbeya Zonal Referral Hospital, Mbeya, Tanzania.
Baylor International Pediatric AIDS Initiative (BIPAI) at Texas Children's Hospital, Baylor College of Medicine, Houston, TX, USA.
BMC Infect Dis. 2017 Feb 6;17(1):123. doi: 10.1186/s12879-017-2236-9.
As access to Xpert expands in high TB-burden settings, its performance against clinically diagnosed TB as a reference standard provides important insight as the majority of childhood TB is bacteriologically unconfirmed. We aim to describe the characteristics and outcomes of children with presumptive TB and TB disease, and assess performance of Xpert under programmatic conditions against a clinical diagnosis of TB as a reference standard.
Retrospective review of children evaluated for presumptive TB in Mbeya, Tanzania. Baseline characteristics were compared by TB disease status and, for patients diagnosed with TB, by TB confirmation status using Wilcoxon rank sum test for continuous variables and the Chi-square test for categorical variables. Sensitivity and specificity were calculated to assess the performance of Xpert, smear, and culture against clinical TB. Kappa statistics were calculated to assess agreement between Xpert and smear to culture.
Among children (N = 455) evaluated for presumptive TB, 70.3% (320/455) had Xpert and 62.8% (286/455) had culture performed on sputa. 34.5% (157/455) were diagnosed with TB: 80.3% (126/157) pulmonary TB, 13.4% (21/157) bacteriologically confirmed, 53.5% (84/157) HIV positive, and 48.4% (76/157) inpatients. Compared to the reference standard of clinical diagnosis, sensitivity of Xpert was 8% (95% CI 4-15), smear 6% (95% CI 3-12) and culture 16% (95% CI 9-24), and did not differ based on patient disposition, nutrition or HIV status.
Despite access to Xpert, the majority of children with presumptive TB were treated based on clinical diagnosis. Reflecting the reality of clinical practice in resource limited settings, new diagnostics such as Xpert serve as important adjunctive tests but will not obviate the need for astute clinicians and comprehensive diagnostic algorithms.
随着在结核病高负担地区Xpert检测的可及性不断扩大，鉴于大多数儿童结核病未经细菌学确诊，以临床诊断的结核病作为参考标准来评估其性能可提供重要见解。我们旨在描述疑似结核病和结核病患儿的特征及转归，并在项目实施条件下，以临床诊断的结核病作为参考标准，评估Xpert的性能。
对在坦桑尼亚姆贝亚接受疑似结核病评估的儿童进行回顾性研究。根据结核病患病状况比较基线特征，对于确诊为结核病的患者，根据结核病确诊状况，采用Wilcoxon秩和检验分析连续变量，采用卡方检验分析分类变量。计算Xpert、涂片和培养针对临床结核病的敏感性和特异性。计算Kappa统计量以评估Xpert与涂片和培养结果之间的一致性。
在接受疑似结核病评估的儿童（N = 455）中，70.3%（320/455）进行了Xpert检测，62.8%（286/455）进行了痰液培养。34.5%（157/455）被诊断为结核病：80.3%（126/157）为肺结核，13.4%（21/157）经细菌学确诊，53.5%（84/157）为HIV阳性，48.4%（76/157）为住院患者。与临床诊断的参考标准相比，Xpert的敏感性为8%（95%CI 4-15），涂片为6%（95%CI 3-12），培养为16%（95%CI 9-24），且不因患者处置方式、营养状况或HIV状态而有所不同。
尽管可使用Xpert检测，但大多数疑似结核病患儿仍基于临床诊断接受治疗。反映了资源有限环境下临床实践的现实情况，像Xpert这样的新诊断方法可作为重要的辅助检测手段，但并不能取代经验丰富的临床医生和全面的诊断算法。
