Daum L T, Peters R P H, Fourie P B, Jonkman K, Worthy S A, Rodriguez J D, Ismail N A, Omar S V, Fischer G W
Longhorn Vaccines & Diagnostics, San Antonio, Texas, USA.
Anova Health Institute, Johannesburg, South Africa; Department of Medical Microbiology, University of Pretoria, South Africa; Department of Medical Microbiology, Maastricht University Medical Centre, Maastricht, The Netherlands.
Int J Tuberc Lung Dis. 2015 May;19(5):552-7. doi: 10.5588/ijtld.14.0769.
Mopani District, South Africa.
To explore remote, molecular detection of Mycobacterium tuberculosis from sputum transported using PrimeStore(®) Molecular Transport Medium (PS-MTM) compared to settings where microscopy or Xpert(®) MTB/RIF is used as the baseline test.
Two sputum specimens were collected from patients with cough of ⩾ 2 weeks at clinics in rural South Africa. Shortly after expectoration and before processing using Xpert, microscopy and liquid culture, a flocked swab was swirled in each of these specimens and placed in PS-MTM. Swabs were stored and transported to the United States at ambient temperature for real-time PrimeMix(®) polymerase chain reaction (PM-PCR).
Of 132 patients, 23 (17%) were positive on microscopy, 39 (30%) on Xpert and 44 (33%) by PS-MTM/PM-PCR. Concordance of PS-MTM/PM-PCR with positive microscopy and Xpert was respectively 96% and 85%. Of 107 microscopy-negative samples, 22 (21%) were positive using PS-MTM/PM-PCR, while 11/91 (12%) Xpert-negative samples were PS-MTM/PM-PCR-positive. PS-MTM/PM-PCR positivity was significantly higher than smear microscopy positivity (P < 0.001), but similar to Xpert (P = 0.33).
PCR testing of specimens transported in PS-MTM would enhance TB diagnosis in settings where smear microscopy is the baseline diagnostic test, and could provide an alternative in settings where Xpert testing is not available.
南非莫帕尼区。
与以显微镜检查或Xpert MTB/RIF作为基线检测的情况相比，探讨使用PrimeStore（®）分子转运培养基（PS-MTM）运输痰液时对结核分枝杆菌进行远程分子检测的情况。
从南非农村诊所中咳嗽≥2周的患者收集两份痰液标本。咳痰后不久且在使用Xpert、显微镜检查和液体培养处理之前，将植绒拭子在每份标本中旋转并置于PS-MTM中。拭子在室温下储存并运往美国进行实时PrimeMix（®）聚合酶链反应（PM-PCR）。
132例患者中，显微镜检查阳性23例（17%），Xpert阳性39例（30%），PS-MTM/PM-PCR阳性44例（33%）。PS-MTM/PM-PCR与显微镜检查阳性和Xpert阳性的一致性分别为96%和85%。在107份显微镜检查阴性的样本中，22份（21%）使用PS-MTM/PM-PCR呈阳性，而在91份Xpert阴性样本中，11份（12%）PS-MTM/PM-PCR呈阳性。PS-MTM/PM-PCR阳性率显著高于涂片显微镜检查阳性率（P<0.001），但与Xpert相似（P = 0.33）。
对用PS-MTM运输的标本进行PCR检测可在以涂片显微镜检查作为基线诊断检测的情况下加强结核病诊断，并且在无法进行Xpert检测的情况下可提供一种替代方法。
