Programa de Pós graduação em Biotecnologia Aplicada à Saúde da Criança e do Adolescente da Faculdades Pequeno Príncipe (FPP), Instituto de Pesquisa Pelé Pequeno Príncipe (IPPPP), Curitiba, Paraná, Brasil.
Complexo Hospital de Clínicas, Universidade Federal do Paraná (CHC-UFPR), Setor de Infectologia, Setor de Bacteriologia, Unidade de Laboratório de Análises Clínicas (ULAC) Curitiba, Paraná, Brasil.
PLoS One. 2021 Mar 3;16(3):e0247185. doi: 10.1371/journal.pone.0247185. eCollection 2021.
Xpert® MTB/RIF has been widely used for tuberculosis (TB) diagnosis in Brazil, since 2014. This prospective observational study aimed to evaluate the performance of Xpert in different contexts during a two-year period: (i) laboratory and clinical/epidemiological diagnosis; (ii) HIV-positive and -negative populations; (iii) type of specimens: pulmonary and extrapulmonary. Overall, 924 specimens from 743 patients were evaluated. The performance of the assays was evaluated considering culture (Lowenstein Jensen or LJ medium) results and composite reference standard (CRS) classification as gold standard. According to CRS evaluation, 219 cases (29.5%) were classified as positive cases, 157 (21.1%) as 'possible TB', and 367 (49.3%) as 'not TB'. Based on culture, Xpert and AFB smear achieved a sensitivity of 96% and 62%, respectively, while based on CRS, the sensitivities of Xpert, AFB smear, and culture were 40.7%, 20%, and 25%, respectively. The pooled sensitivity and specificity of Xpert were 96% and 94%, respectively. Metric evaluations were similar between pulmonary and extrapulmonary samples against culture, whereas compared to CRS, the sensitivities were 44.6% and 29.3% for the pulmonary and extrapulmonary cases, respectively. The Xpert detected 42/69 (60.9%) patients with confirmed TB and negative culture on LJ medium, and 52/69 (75.4%) patients with negative AFB smear results. There was no significant difference in the diagnostic accuracy based on the types of specimens and population (positive- and negative-HIV). Molecular testing detected 13 cases of TB in culture-negative patients with severe immunosuppression. Resistance to rifampicin was detected in seven samples. Herein, Xpert showed improved detection of pulmonary and extrapulmonary TB cases, both among HIV-positive and -negative patients, even in cases with advanced immunosuppression, thereby performing better than multiple other diagnostic parameters.
Xpert® MTB/RIF 自 2014 年以来在巴西已广泛用于结核病（TB）诊断。本前瞻性观察性研究旨在评估 Xpert 在两年期间不同情况下的表现：（i）实验室和临床/流行病学诊断；（ii）HIV 阳性和阴性人群；（iii）标本类型：肺和肺外。总共评估了 743 名患者的 924 份标本。根据培养（Lowenstein Jensen 或 LJ 培养基）结果和综合参考标准（CRS）分类，评估了检测方法的性能。根据 CRS 评估，219 例（29.5%）被归类为阳性病例，157 例（21.1%）为“可能的结核病”，367 例（49.3%）为“非结核病”。根据培养，Xpert 和 AFB 涂片的敏感性分别为 96%和 62%，而根据 CRS，Xpert、AFB 涂片和培养的敏感性分别为 40.7%、20%和 25%。Xpert 的合并敏感性和特异性分别为 96%和 94%。Xpert 在肺外样本与培养物之间的衡量评估相似，而与 CRS 相比，肺外样本的敏感性分别为 44.6%和 29.3%。Xpert 检测到 42/69（60.9%）例经 LJ 培养基培养证实为结核病且培养阴性的患者，以及 52/69（75.4%）例 AFB 涂片结果阴性的患者。根据标本类型和人群（HIV 阳性和阴性），诊断准确性没有显著差异。分子检测在培养阴性且严重免疫抑制的患者中发现了 13 例结核病病例。在 7 个样本中检测到利福平耐药性。在此，Xpert 显示出对肺和肺外结核病病例的检测能力有所提高，无论是在 HIV 阳性还是阴性患者中，甚至在免疫抑制程度较高的情况下也是如此，其表现优于其他多个诊断参数。
