Tagliani Elisa, Alagna Riccardo, Tafaj Silva, Hafizi Hasan, Cirillo Daniela Maria
Emerging Bacterial Pathogens Unit, Division of Immunology, Transplantation and Infectious Diseases, IRCCS San Raffaele Scientific Institute, Olgettina 58, 20132, Milan, Italy.
University Hospital Shefqet Ndroqi, Tirana, Albania.
BMC Infect Dis. 2017 Oct 2;17(1):663. doi: 10.1186/s12879-017-2756-3.
Maintaining the quality of clinical specimens for tuberculosis (TB) testing is a major challenge in many high TB burden-limited resources countries. Sample referral systems in low and middle income countries are often weak and the maintenance of the cold-chain challenging and very costly for TB programs. The development of transport media allowing the preservation of samples without refrigeration is critical for increasing access to TB diagnostic services and for reducing the costs related to testing.
We evaluated the performance of OMNIgene-SPUTUM (OM-S) reagent for the maintenance of Mycobacterium tuberculosis (MTB) viability in sputum samples in the absence of refrigeration and its capacity to stabilize nucleic acid for molecular testing. A total of 329 sputum specimens from presumptive TB cases collected at the National Reference Laboratory in Tirana, Albania, were either decontaminated by a conventional method or processed with OM-S reagent and stored at room temperature. Samples in OM-S were shipped to the Supranational Reference Laboratory in Milan, Italy, at various times and processed for liquid culture.
Our data show that OM-S maintains MTB viability for at least three weeks in the absence of refrigeration and improves the quality of culture resulting in a contamination rate lower than 0.5%. However, a significant delay in the time to culture positivity was observed for samples stored for more than two weeks in OM-S.
Overall, OM-S offers multiple benefits both at laboratory and TB national program level by increasing the availability to quality diagnostics, promoting access to health care services and strengthening TB patient care especially in hard to reach populations.
在许多结核病负担较重的资源有限国家，维持用于结核病检测的临床标本质量是一项重大挑战。低收入和中等收入国家的样本转诊系统往往薄弱，冷链维护对结核病项目来说具有挑战性且成本高昂。开发无需冷藏即可保存样本的运输介质对于增加结核病诊断服务的可及性以及降低检测相关成本至关重要。
我们评估了OMNIgene - 痰液（OM - S）试剂在无冷藏条件下维持痰液样本中结核分枝杆菌（MTB）活力的性能及其稳定核酸用于分子检测的能力。从阿尔巴尼亚地拉那国家参考实验室收集的总共329份疑似结核病病例的痰液标本，要么采用传统方法进行净化处理，要么用OM - S试剂处理并在室温下储存。用OM - S处理的样本在不同时间被运往意大利米兰的超国家参考实验室并进行液体培养。
我们的数据表明，OM - S在无冷藏条件下可使MTB活力维持至少三周，并提高培养质量，使污染率低于0.5%。然而，在OM - S中储存超过两周的样本，培养阳性时间出现了显著延迟。
总体而言，OM - S在实验室和国家结核病项目层面都带来了多重益处，通过提高优质诊断的可及性、促进获得医疗保健服务以及加强结核病患者护理，特别是在难以到达的人群中。
