Published: 2017-10-27

Role of induced sputum with hypertonic saline in the early diagnosis of no / inadequate sputum or sputum smear negative suspected cases of pulmonary tuberculosis

Mayank Kapur, Atul Luhadia, Shanti Kumar Luhadia


Background: Pulmonary Tuberculosis is one of the common infections in the world, especially in developing countries like India and is a leading cause of morbidity and mortality worldwide. Therefore, early diagnosis and microbiological confirmation of pulmonary TB is important. This study was done to assess the role of induced sputum with hypertonic saline in suspected pulmonary TB patients who produce no or inadequate sputum or who are sputum for AFB smear negative.

Methods: 100 patients with clinical and radiological evidence of pulmonary TB with no or inadequate sputum or who are smear negative with spontaneous sputum were included in the study. Sputum was induced with 5ml of 3% hypertonic saline delivered through nebulizer and then was sent for Ziehl Neelsen staining examination.

Results: 96 patients could produce adequate sputum after sputum induction. In 47 patients, sputum for AFB smear was found positive after induction.

Conclusions: Sputum induction is a safe, cheap and non-invasive procedure and offers an alternative or additional approach in the diagnosis of sputum smear-negative suspected pulmonary tuberculosis patients and would enhance sensitivity for the diagnosis of tuberculosis.



Hypertonic saline, Induced sputum, Sputum smear negative pulmonary tuberculosis (SSN-PTB)

Full Text:



WHO Global tuberculosis report; 2016. Available at->tb>global_report.

TB India; 2012. Available form: Annual status report/tbcindia. Available at

Kochi A. The global tuberculosis situation and the new control strategy of the World Health Organization Tubercl. 1991;72:1-6.

World Health Organization. Treatment of tuberculosis: guidelines for national programs. Geneva: World Health Organization; 1993.

Swai HF, Mugusi FM, Mbwambo JK. Sputum smear negative pulmonary TB: Sensitivity and Specificity of diagnostic algorithm. BMC Res Notes. 2011;4:475.

Cattamanchi A, Dowdy DW, Davis JL, Worodria W, Yoo S, Joloba M, et al. Sensitivity of direct versus concentrated sputum smear microscopy in HIV-infected patients suspected of having pulmonary tuberculosis. BMC Infect Dis. 2009;9: 53.

Foulds J, O’Brien R. New tools for the diagnosis of tuberculosis; the perspective of developing countries. Int J tuberc Lung Dis. 1998;2:778-83.

Ramachandran V, Pachamuthu B, Esaki SM, Kailapuri MG, Settu H, Anitha CJ, et al. Value of single acid-fast bacilli sputum smears in the diagnosis of tuberculosis in HIV-positive subjects. J Med Microbiol. 2007;56:1709-10.

Hong Kong Chest service/tuberculosis research center, Madras/ British Research Council. A study of the character and course of sputum smear negative pulmonary tuberculosis. Tubercle. 1981; 62:155-67.

Mohan A, Pande JN, Sharma SK, Rattan A, Guleria R, Khilnani GC. Bronchoalveolar lavage in pulmonary tuberculosis: a decision analysis approach. Q J Med. 1995;88:269-76.

Robinson B. Policy, Protocols and Procedures for Sputum Induction for Diagnosis of Respiratory Infections. John Hunter Hospital; 1997.

Gupta KB, Garg S. Use of sputum induction for establishing diagnosis in suspected pulmonary tuberculosi. Indian J Tuberc. 2005;52:143-6.

Gonzalez-Angulo Y, Wiysonge CS, Geldenhuys H, Hanekom W, Mahomed H, Hussey G, et al. Sputum induction for the diagnosis of pulmonary tuberculosis: a systematic review and meta-analysis. Eur J Clin Microbiol Infect Dis. 2012;31(7):1619-30.

Li LM, Bai LQ, Yang HL, Xiao CF, Tang RY, Cheu YF, et al. Sputum induction to improve diagnostic yield in patients with suspected pulmonary tuberculosis. Int J Tubercle Lung Dis. 1999;3(2): 1137-9.

Conde MB, Soares SL, Mello FC, Rezende Vm, Almeida LL, Reingold AL, et al. Comparison of sputum induction with fiberoptic bronchoscopy in the diagnosis of tuberculosis: experience at an acquired immune deficiency syndrome reference centre in Rio de Janeiro, Brazil. Am J Respir Crit Care Med. 2000;162: 2238-40.

Menzies D. Sputum induction: Simpler,cheaper, and safer- but is it better? Am J Respir Crit Care Med 2003;167:676-7.

Gupta KB, Garg S. Use of sputum induction for establishing diagnosis in suspected pulmonary tuberculosi. Indian J tuberc. 2005;52:143-6.

Atiq-ur-Rehman M, Naseem A, Hussain T. Comparison of Diagnostic Yield of AFB with Sputum Induction to Spontaneous Sputum Examination in Suspected Pulmonary Tuberculosis. J Coll Physicians Surg Pak. 2009;19(8):506-9.

Biswas S, Das A, Sinha A, Das SK, Bairagya TD. The role of induced sputum in the diagnosis of pulmonary tuberculosis. Lung India. 2013;3093: 199-202.