Quality of Sputum Specimen Samples Submitted for Culture and Drug Susceptibility Testing at the National Tuberculosis Reference Laboratory-Uganda, July-October 2013


Setting: The Uganda National Tuberculosis Reference Laboratory (NTRL) in Kampala. Objective: The proportion of poor quality specimens received for drug susceptibility testing (DST) at the NTRL and factors contributing to poor specimen quality were assessed. Design: A cross-sectional study was conducted of sputum samples received at the NTRL from patients at high risk for multi-drug-resistant tuberculosis (MDR TB) during July-October 2013. Demographic, clinical, and bacte-riological data were abstracted from laboratory records. A poor quality sample failed to meet any one of four criteria: ≥3 milliliter (ml) volume, delivered within 72 hours, triple packaged, and non-salivary appearance. Results: Overall, 365 (64%) of 556 samples were of poor quality; 89 (16%) were not triple packaged, 44 (8%) were <3 mls, 164 (30%) were not delivered on time, and 215 (39%) were salivary in appearance. Poor quality specimens were more likely to be collected during the eighth month of TB treatment (OR = 2.5, CI = 1.2 - 5.1), from the East or Northeast zones (OR = 2.2, CI = 1.1 - 4.8), and from patients who previously defaulted from treatment (OR = 1.9, CI = 1.1 - 3.2). Conclusion: The majority of sputum samples had poor quality. Additional efforts are needed to improve quality of samples collected at the end of treatment, from East and Northeast zones, and from patients who had previously defaulted.

Share and Cite:

Bulage, L. , Imoko, J. , Kirenga, B. , Lo, T. , Byabajungu, H. , Musisi, K. , Joloba, M. and Bloss, E. (2015) Quality of Sputum Specimen Samples Submitted for Culture and Drug Susceptibility Testing at the National Tuberculosis Reference Laboratory-Uganda, July-October 2013. Journal of Tuberculosis Research, 3, 97-106. doi: 10.4236/jtr.2015.33015.

Conflicts of Interest

The authors declare no conflicts of interest.


[1] WHO (2014) Global Tuberculosis Report 2013. Geneva.
[2] WHO (2012) Global Tuberculosis Report 2011. Geneva.
[3] Lukoye, D., Adatu, F., Musisi, K., Kasule, G.W., Were, W., Odeke, R., Kalamya, J.N., Awor, A., Date, A. and Joloba, M.L. (2013) Anti-Tuberculosis Drug Resistance among New and Previously Treated Sputum Smear-Positive Tuberculosis Patients in Uganda: Results of the First National Survey. PLoS One, 8.
[4] Uganda Ministry of Health (2011) Uganda National Guidelines for the Programmatic Management of Drug Resistant Tuberculosis. Kampala.
[5] Uganda Ministry of Health (2009) National TB and Leprosy Program-Uganda. Tuberculosis Specimen Referral System -Training Manual. Kampala.
[6] Ho, J., Marks, G.B. and Fox, G.J. (2015) The Impact of Sputum Quality on Tuberculosis Diagnosis: A Systematic Review. International Journal of Tuberculosis and Lung Disease, 19, 537-544.
[7] Uganda Ministry of Health (2010) NTLP-Uganda. Tuberculosis Specimen Referral System-Training Manual. Kampala.
[8] WHO (2005) Guidance on Regulations for the Transport of Infectious Substances. WHO/CDS/CSR/LYO/2005.22: Geneva.
[9] Uganda Ministry of Health (2010) National TB Reference Laboratory Standard Operating Procedure for Primary Sample Collection and Transport. Kampala.
[10] Yoon, S.H., Lee, N.K. and Yim, J.J. (2012) Impact of Sputum Gross Appearance and Volume on Smear Positivity of Pulmonary Tuberculosis: A Prospective Cohort Study. BMC Infectious Diseases.
[11] Paramasivan, C.N., Narayana, A.S., Prabhakar, R., Rajagopal, M.S., Somasundaram, P.R. and Tripathy, S.P. (1983) Effect of Storage of Sputum Specimens at Room Temperature on Smear and Culture Results. Tubercle, 64, 119-124. http://dx.doi.org/10.1016/0041-3879(83)90036-3
[12] Tessema, B., Beer, J., Emmrich, F., Sack, U. and Rodloff, A.C. (2011) Rate of Recovery of Mycobacterium tuberculosis from Frozen Acid-Fast-Bacillus Smear-Positive Sputum Samples Subjected to Long-Term Storage in Northwest Ethiopia. Journal of Clinical Microbiology, 49, 2557-2561.
[13] Alisjahbana, B., van Crevel, R., Danusantoso, H., Gartinah, T., Soemantri, E.S., Nelwan, R.H., et al. (2005) Better Patient Instruction for Sputum Sampling Can Improve Microscopic Tuberculosis Diagnosis. The International Journal of Tuberculosis and Lung Disease, 9, 814-817.
[14] Waitzkin, H. and Stoeckle, J.D. (1976) Information Control and the Micropolitics of Health Care. Social Science & Medicine, 10, 263-276. http://dx.doi.org/10.1016/0037-7856(76)90070-6
[15] Sakundarno, M., Nurjazuli, N., Jati, S.P., Sariningdyah, R., Purwadi, S., Alisjahbana, B. and van der Werf, M.J. (2009) Insufficient Quality of Sputum Submitted for Tuberculosis Diagnosis and Associated Factors, in Klaten District, Indonesia. BMC Pulmonary Medicine, 9, 16. http://dx.doi.org/10.1186/1471-2466-9-16
[16] Centers for Disease Control and Prevention (2015) Core Curriculum. Chapter 4: Diagnosis of TB Disease. http://www.cdc.gov/tb/education/corecurr/pdf/chapter4.pdf
[17] Macq, J., Solis, A., Velázquez, H. and Dujardin, B. (2005) Informing the TB Suspect for Sputum Sample Collection and Communicating Laboratory Results in Nicaragua: A Neglected Process in Tuberculosis Case Finding. Salud Pública de México, 47, 303-307. http://dx.doi.org/10.1590/S0036-36342005000400008
[18] Shinnick, T.M., Starks, A.M., Alexander, H.L. and Castro, K.G. (2015) Evaluation of the Cepheid Xpert MTB/RIF Assay. Expert Review of Molecular Diagnostics, 15, 9-22.
[19] Muture, B.N., Keraka, M.N., Kimuu, P.K., Kabiru, E.W., Ombeka, V.O. and Oguya, F. (2011) Factors Associated with Default from Treatment among Tuberculosis Patients in Nairobi Province, Kenya: A Case Control Study. BMC Public Health, 11, 696. http://dx.doi.org/10.1186/1471-2458-11-696

Copyright © 2023 by authors and Scientific Research Publishing Inc.

Creative Commons License

This work and the related PDF file are licensed under a Creative Commons Attribution 4.0 International License.