Yield of direct sputum smear examination in pulmonary tuberculosis suspect cases with hemoptysis

Abstract

Introduction: Hemoptysis is one of the cardinal symptoms of pulmonary tuberculosis (PTB) as per the Revised National Tuberculosis Control Programme 2016 guidelines. Hemoptysis in tuberculosis patients usually occurs in those who have a large bacillary load like that in a cavity. Direct smear done from the sputum of a PTB suspect with hemoptysis should have a higher diagnostic yield due to the greater bacillary load in such patients. Keeping this intention in mind, our study was conducted to systematically inquire into the efficacy of a cheap and easily available test like direct sputum smear examination in PTB suspect cases of hemoptysis. Materials and Methods: This was a prospective, hospital-based, analytical study, conducted on 100 PTB suspects with hemoptysis, who were attending the Outpatient and Emergency Department of National Institute of Tuberculosis and Respiratory Diseases, New Delhi, India. Patients were enrolled over a period of 8 months. All patients underwent routine clinical and radiological evaluation and sputum examination in the form of direct smear by Ziehl–Neelsen (ZN) staining and mycobacterium growth indicator tube (MGIT) culture. Results: Most of the patients (25%) belonged to the age bracket 16–25 years followed by 24% of patients who belonged to the age group of 26–35 years. Fifty-two percent of patients had the cavity in their chest X-ray findings in which mostly were the unilateral cavity (39%). Direct sputum microscopy was found to be positive in 56% of patients. In comparison to MGIT, it had a sensitivity of 79% and a positive predictive value of 92%. Conclusion: Direct smear examination in hemoptysis patients should be a first line essential investigation as it is a good, cheap, easily available, and quick test. The yield of the test increases if the patient is young, male, with a previous history of antitubercular therapy intake and cavitary lesions on the radiological findings.

Keywords

• hemoptysis
• pulmonary tuberculosis suspect
• yield of sputum direct smear
• ziehl–neelsen staining