Detection of mycobacterium tuberculosis in the saliva of patients having pulmonary tuberculosis

Abstract

Aims: The purpose of this study was to determine the efficacy of saliva as a sample for diagnosing pulmonary tuberculosis(T.B.) by looking for acid fast bacilli in a direct smear and comparing it with sputum and to determine whether the isolation of M. tuberculosis is from the lung or disseminated through blood. Material and Methods : The study sample consisted of 25 patients of both sexes. Age range was (17 - 65) years . Approximately 2 ml of unstimulated mixed saliva from each subject and parotid saliva were collected for direct smear for acid fast bacilli by Ziehl-Nelson acid fast stain. Five samples were inoculated on Lowenstein Jensen media and storenbrink media .Results: About 60% of unstimulated mixed saliva revealed positive acid fast bacilli, while all samples of parotid saliva showed negative acid fast bacilli. The five samples of saliva which were inoculated on Lowenstein Jensen media and stonebrink media showed positive culture. To our knowledge, we did not find any study performed on saliva as a sample for diagnosis of pulmonary tuberculosis to compare our finding with these studies, so the comparison was made between the sensitivity of saliva and the sensitivity of sputum . In this study, the sensitivity of direct smear of saliva for A.F.B was equal to 60% of the sensitivity of sputum. The sensitivity of direct smear of sputum for A.F.B. ranged from (2280%). There were no clinical manifestations like gummas; granulomas; ulcer; alveolar abscess and osteitis. CONCLUSION: This clinical and laboratory study revealed that M Tuberculosis which was present in the mixed saliva resulted from contact of oral tissue with infected sputum; Mixed saliva was less efficient than sputum in diagnosis of T.B. disease . Saliva can be inoculated on different media and that newly diagnosed patients with T.B disease don't have any clinical manifestations in the oral cavity