Godlove T. Chaula , Lucy Namkinga , Ally Mahadhy , Wilber Sabiiti , Nyanda Elias Ntinginya , Bariki Mtafya
{"title":"High centrifugation speed improves recovery of M. tuberculosis and yield of culture","authors":"Godlove T. Chaula , Lucy Namkinga , Ally Mahadhy , Wilber Sabiiti , Nyanda Elias Ntinginya , Bariki Mtafya","doi":"10.1016/j.tube.2025.102633","DOIUrl":null,"url":null,"abstract":"<div><h3>Background</h3><div>We assessed the impact of centrifugation on recovery of <em>Mycobacterium tuberculosis</em> (<em>M.tb</em>).</div></div><div><h3>Methods</h3><div>We used 0.5 McFarland from the 2 weeks <em>M. tb,</em> H37Rv culture and homogenized sputum for our experiments. Samples were decontaminated by 2 % NaOH for 20 min and with PBS for controls. Decontaminated aliquots were centrifuged at 2000×<em>g</em>, 3000×<em>g</em> and 6000×<em>g</em> for 40 min and inoculated on MGIT and LJ media. MGITs were incubated into the BACTEC MGIT 960 Systems following BD manuals and data analyzed on GraphPad Software.</div></div><div><h3>Results</h3><div>The positivity (days) for <em>M. tb</em>, <em>H37Rv</em> in MGIT and LJ decreased from 20.4 to 17.7 and from 47.6 to 26.6 at 2000×<em>g</em> and 6000×<em>g</em>, respectively; P > 0.05. For controls, MGIT and LJ positivity (days) decreased from 19 to 10 and from 39.2 to 11.2 at 2000×<em>g</em> and 6000×<em>g</em>, respectively; P > 0.05. MGIT positivity was 6(60 %) at 2000×<em>g</em> and 8(80 %) at 6000×<em>g</em>, corresponding to mean (±SD) of 13.7 ± 6.7 and 9.06 ± 4.6 days, respectively for sputum. LJ positivity was 1(10 %) at 2000×<em>g</em> and 7(70 %) at 6000×<em>g</em>. MGIT contamination for controls (sputum) was over 50 % and 80 % for LJ.</div></div><div><h3>Conclusion</h3><div>Higher centrifugation speed improves yield and sensitivity of TB culture.</div></div>","PeriodicalId":23383,"journal":{"name":"Tuberculosis","volume":"152 ","pages":"Article 102633"},"PeriodicalIF":2.8000,"publicationDate":"2025-03-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Tuberculosis","FirstCategoryId":"3","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S1472979225000289","RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"IMMUNOLOGY","Score":null,"Total":0}
引用次数: 0
Abstract
Background
We assessed the impact of centrifugation on recovery of Mycobacterium tuberculosis (M.tb).
Methods
We used 0.5 McFarland from the 2 weeks M. tb, H37Rv culture and homogenized sputum for our experiments. Samples were decontaminated by 2 % NaOH for 20 min and with PBS for controls. Decontaminated aliquots were centrifuged at 2000×g, 3000×g and 6000×g for 40 min and inoculated on MGIT and LJ media. MGITs were incubated into the BACTEC MGIT 960 Systems following BD manuals and data analyzed on GraphPad Software.
Results
The positivity (days) for M. tb, H37Rv in MGIT and LJ decreased from 20.4 to 17.7 and from 47.6 to 26.6 at 2000×g and 6000×g, respectively; P > 0.05. For controls, MGIT and LJ positivity (days) decreased from 19 to 10 and from 39.2 to 11.2 at 2000×g and 6000×g, respectively; P > 0.05. MGIT positivity was 6(60 %) at 2000×g and 8(80 %) at 6000×g, corresponding to mean (±SD) of 13.7 ± 6.7 and 9.06 ± 4.6 days, respectively for sputum. LJ positivity was 1(10 %) at 2000×g and 7(70 %) at 6000×g. MGIT contamination for controls (sputum) was over 50 % and 80 % for LJ.
Conclusion
Higher centrifugation speed improves yield and sensitivity of TB culture.
期刊介绍:
Tuberculosis is a speciality journal focusing on basic experimental research on tuberculosis, notably on bacteriological, immunological and pathogenesis aspects of the disease. The journal publishes original research and reviews on the host response and immunology of tuberculosis and the molecular biology, genetics and physiology of the organism, however discourages submissions with a meta-analytical focus (for example, articles based on searches of published articles in public electronic databases, especially where there is lack of evidence of the personal involvement of authors in the generation of such material). We do not publish Clinical Case-Studies.
Areas on which submissions are welcomed include:
-Clinical TrialsDiagnostics-
Antimicrobial resistance-
Immunology-
Leprosy-
Microbiology, including microbial physiology-
Molecular epidemiology-
Non-tuberculous Mycobacteria-
Pathogenesis-
Pathology-
Vaccine development.
This Journal does not accept case-reports.
The resurgence of interest in tuberculosis has accelerated the pace of relevant research and Tuberculosis has grown with it, as the only journal dedicated to experimental biomedical research in tuberculosis.