Comparative study of OMNIgene®•SPUTUM reagent versus cold-chain for the transportation of sputum samples to GeneXpert®MTB/RIF testing sites in Malawi

BMC Infectious Diseases

P. S. Curry¹  A. Weirich¹  C. D. Kelly-Cirino¹  A. Dimba²  Wondwossen A. Alemayehu³  A. Trusov³  R. Nalikungwi³  S. Dalebout³  E. Ahmed³  S. Neri³ 

[1] DNA Genotek, Ottawa, Ontario, Canada;Ministry of Health, National TB Program, Lilongwe, Malawi;Project HOPE, United States and Africa, PO Box 13395, Addis Ababa, Ethiopia;

关键词: OMNIgene;    Sputum;    GeneXpert;    Mycobacterium tuberculosis;    Preservation;    Specimen transport medium;    Molecular detection;   

DOI  :  10.1186/s12879-019-4070-8

来源: publisher

【 摘 要 】

BackgroundThe study was conducted in a remote sputum sample collection sites and GeneXpert® MTB/RIF testing centers to detect Mycobacterium tuberculosis in Malawi. The main purpose of the study was to evaluate whether sputum samples stored and transported with OMNIgene®•SPUTUM (OM-S) medium perform comparably to the routine cold-chain stored and transported samples for GeneXpert testing to detect Mycobacterium tuberculosis.MethodsTwo sputum samples from each of 362 tuberculosis suspects were randomly assigned to the OMNIgene treated (OM-S group) or the standard-of-care group (SOC; transported via cold chain). All specimens were tested at regional GeneXpert testing sites using the expectorated (raw) sputum protocol. Demographic, clinical, transport/storage and Xpert data were recorded for each specimen pair. Agreement between the SOC and OM-S groups’ Xpert results was evaluated using Cohen’s kappa analysis.ResultsMean patient age was 42.3 years (range 2–79 years), 77% of patients were female, and 80% were HIV-positive. Mean transport/storage time was 6.7 days (range, 0–29 days). The rates of MTB positivity for the OM-S and SOC groups were comparable (11.8 and 11.2%, respectively), inter-test agreement was “very good” (κ = 0.97), and overall percent agreement was 99%. Two specimen pairs (both mucoid, one 13 days transport, one 1 day transport) had discordant Xpert results.ConclusionOM-S-treated sputum specimens can undergo multi-day ambient-temperature storage as well as transport and yield Xpert results comparable to those of cold-chain-transported samples in Malawi.

【 授权许可】

CC BY