Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2014 Oct 16:19:162.
doi: 10.11604/pamj.2014.19.162.3658. eCollection 2014.

Microscopic examination and smear negative pulmonary tuberculosis in Ethiopia

Tibebe Seyoum Keflie  1 , Gobena Ameni  2
Affiliations

Microscopic examination and smear negative pulmonary tuberculosis in Ethiopia

Tibebe Seyoum Keflie et al. Pan Afr Med J. .

Abstract

Introduction: Tuberculosis causes illness among millions of people each year and ranks as the second leading cause of death from infectious disease worldwide. The aim of this study was to investigate the detection rate of microscopic examination and estimate risk of transmission of TB by smear negative pulmonary TB patients.

Methods: A cross-sectional study and retrospective data analysis on TB were undertaken in Northwest Shewa, Ethiopia. Microscopic examination, bacterial culture and PCR were performed. The statistical analysis was made by using STATA software version 10.

Results: A total of 92 suspected TB cases was included in the study. Of these, 27.17% (25/92) were positive for microscopic examination and 51% (47/92) for culture. The sensitivity and specificity of microscopic examination with 95% CI were 48.94% (34.08% to 63.93%) and 95.56% (84.82 to 99.33%), respectively. The positive and negative predictive values were 92% (73.93% to 98.78%) and 64.18% (51.53% to 75.53%), respectively. Of 8150 pulmonary TB cases in the retrospective study, 58.9% was smear negative. The proportion of TB-HIV co-infection was 28.66% (96/335).

Conclusion: The sensitivity of microscopic examination was 48.94% which was very low. The poor sensitivity of this test together with the advent of HIV/AIDS elevated the prevalence of smear negative pulmonary TB. This in turn increased the risk of TB transmission.

Keywords: Microscopic examination; sensitivity; smear negative pulmonary TB; specificity.

PubMed Disclaimer

Figures

Figure 1
Figure 1
Diagnostic algorithm of pulmonary TB adopted from FMOH, 2013
Figure 2
Figure 2
Trend of smear positive and negative pulmonary tuberculosis cases in Northwestern Shewa between 2002 and 2006
Figure 3
Figure 3
Burden of smear positive and negative pulmonary TB in Northwestern Shewa
See this image and copyright information in PMC

References

    1. WHO. WHO report; 2013. Global Tuberculosis Report.
    1. Karen RS, Megan H, Vivienne NG, et al. Fluorescence versus conventional sputum smear microscopy for tuberculosis: a systematic review. Lancet Infect Dis. 2006;6(9):570–81. - PubMed
    1. Karen SS, Mohan A. Multidrug-resistant tuberculosis: a menace that threatens to destabilize tuberculosis control. Chest. 2006;130(1):261–272. - PubMed
    1. Philippe G, Dennis F, Katherine F, Mario R. Global Epidemiology of Tuberculosis. Seminars in Respiratory and Critical Care Medicine. 2013;34(1):3–16. - PubMed
    1. FMOH. Federal Democratic Republic of Ethiopia Ministry of Health guidelines for clinical and programmatic management of TB, TB/HIV and Leprosy. Fifth edition. Addis Ababa: FMOH; 2013.