Investigation of OMNIgene•SPUTUM performance in delayed tuberculosis testing by smear, culture, and Xpert MTB/RIF assays in Uganda
Tóm tắt
OMNIgene•SPUTUM (OM-S) is a sample transport reagent designed to work with all tuberculosis diagnostics while eliminating the need for cold chain. OM-S-treated sputum samples were assayed in several tests after multiday holds. Raw sputa from 100 patients underwent direct smear microscopy, were manually split and assigned to the OM-S group [OM-S added at collection (no other processing required) and tested after 0- to 5-day holds at room temperature] or standard-of-care (SOC) group (NaOH/N-acetyl L-cysteine decontamination, all tested on day of collection). Concentrated smear microscopy, Lowenstein Jensen (LJ) culture, and mycobacteria growth indicator tube (MGIT) culture were performed. For patients with negative direct smear, a second sample was split, with SOC (raw sputum) and OM-S portions (sediment) tested in the Xpert MTB/RIF (Xpert) assay. OM-S group and SOC group results were strongly concordant on all four tests [range, 89% (MGIT)–97% (Xpert)]. OM-S MGIT, LJ, and Xpert tests were in statistical agreement with SOC MGIT as reference. OM-S specimens had lower culture contamination rates (3% vs. 10% LJ; 2% vs. 5% MGIT) but required, on average, 5.6 additional days to become MGIT-positive. The findings suggest that samples held/transported in OM-S are compatible with smear microscopy, LJ or MGIT culture, and Xpert, and perform comparably to fresh sputum samples. Larger feasibility studies are warranted.
Tài liệu tham khảo
Stop TB Partnership. High-burden Countries Lists, World Health Organization. Available at: http://www.stoptb.org/countries/tbdata.asp. Accessed 02/09/2017.
Stop TB Partnership. Global Plan to End TB 2016–2020. Available at: http://www.stoptb.org/global/plan/plan2/. Accessed 02/09/2017.
DNA Genotek Product Data Sheet PD-BR-00195. Available at: www.dnagenotek.com. Accessed 02/09/2017.
DNA Genotek Product Data Sheet PD-BR-00196. Available at: www.dnagenotek.com. Accessed 02/09/2017.
Niles J, Ray B, Curry P, Kelly-Cirino C. Compatibility of OMNIgene® SPUTUM and prepIT® MAX with molecular assays for tuberculosis: Real-time PCR and Hain Lifescience GenoType MTBC line probe assay. DNA Genotek Whitepaper PD-WP-00051. Available at: www.dnagenotek.com. Accessed 02/09/2017.
Kelly-Cirino CD, Curry PS, Marola J, Helstrom NK, Salfinger M. Novel multi-day sputum transport reagent works with routine tuberculosis tests and eliminates need for cold chain: preliminary study of compatibility with the Xpert® MTB/ RIF assay. Diagn Microbiol Infect Dis 2016;86:273–6.
GeneXpert® Xpert® MTB/RIF Assay package insert, May 2015. Cepheid. Available at: http://www.cepheid.com/administrator/components/com_productcatalog/library-files/3a9ca7ef6b9b88dc736e5a437f41eb3a-Xpert-MTBRIF-ENGLISH-PackageInsert-301-1404-Rev-C.pdf. Accessed 02/09/2017.
Sergeant, ESG, 2016. EpiTools epidemiological calculators. Ausvet Pty Ltd. Available at: http://epitools.ausvet.com.au. Accessed 02/09/2017.
Landis JR, Koch GG. The measurement of observer agreement for categorical data. Biometrics 1977;33:159–74.