New possibilities to diagnose pulmonary tuberculosis at a pulmonology inpatient department

Abstract

The aim of the study was to investigate new methods for pulmonary tuberculosis (TB) detection at a pulmonology inpatient department.Methods. Pulmonary TB cases (n = 49) newly diagnosed at a pulmonology department of a hospital were involved in the study; among them, 69.4% of patients were infected with human immunodeficiency virus (HIV). All patients were asked if he/she had previously contacted with other TB patients, and if he/she was diagnosed with TB previously. The patients were also about family history. Posteroanterior and lateral chest X-ray and laboratory analyses were performed in all patients. Mycobacteria tuberculosis (MBT) were searched using smear microscopy, GeneXpert MTB/RIF molecular method and culturing (BACTEC MGIT) of sputum and bronchoalveolar lavage fluid (BALF) obtained during bronchoscopy. Patients with positive results only were included in the analysis in order to investigate and to compare diagnostic value of the methods.Results. Questioning patients at admission was useful to diagnose TB in 4% of patients. Sputum smears were positive in 12 patients (27.3%). BALF was obtained in 18 patients (36.7%); among them, MBT was identified in 52 (5%). Molecular testing was positive in all 49 patients (100%); among them, BACTEC MGIT culturing yielded MBT in 48 patients (97.9%). In patients with negative sputum smears during the first 3 days after admission, GeneXpert required 10.4 ± 5.3 days.Conclusion. GeneXpert method was highly useful to diagnose TB and was comparable with BACTEC. Routine sputum and BALF smear microscopy was significantly less rapid and less sensitive method. The diagnostic accuracy could be increased with the use of molecular methods in patients with negative sputum smears obtained at a general hospital. Therefore, molecular methods could be used in patients highly suspected for TB.