Clinical utility of a commercial ligase chain reaction kit for the diagnosis of smear-negative pulmonary tuberculosis

• Published in: The international journal of tuberculosis and lung disease Vol. 3; no. 5; pp. 421 - 425
• Main Authors: KWIATKOWSKA, S, MARCZAK, J, ZIEBA, M, NOWAK, D
• Format: Journal Article
• Language: English
• Published: Paris, France IUATLD 01.05.1999; Union internationale contre la tuberculose et les maladies respiratoires
• Subjects: Adult; Bacterial diseases; Bacteriological Techniques; Biological and medical sciences; Bronchoalveolar Lavage Fluid; DNA, Bacterial - metabolism; Evaluation Studies as Topic; Female; Human bacterial diseases; Humans; Infectious diseases; Ligase Chain Reaction; Ligases - metabolism; Male; Medical sciences; Middle Aged; Mycobacterium Tuberculosis; Mycobacterium tuberculosis - isolation & purification; Polymerase Chain Reaction; Reagent Kits, Diagnostic; Sensitivity and Specificity; Sputum - microbiology; Tuberculosis; Tuberculosis and atypical mycobacterial infections; Tuberculosis, Pulmonary - diagnosis; Infection; Human; Tuberculosis; Respiratory disease; Ligase chain reaction; Lung; Kit; Bacteriosis; Mycobacterial infection; Diagnosis; Method
• ISSN: 1027-3719; 1815-7920

SETTING: In paucibacillary forms of smear-negative tuberculosis it is very difficult to establish a correct and rapid diagnosis, as several weeks are usually required to obtain positive results from culture. In the last few years new rapid techniques based on molecular biology for the detection of Mycobacterium tuberculosis have been introduced.OBJECTIVE: The aim of this study was to evaluate the utility of the ligase chain reaction method (LCx, Abbott) for the diagnosis of smear-negative pulmonary tuberculosis.DESIGN: Thirty smear-negative patients with radiographic changes and clinical signs consistent with TB participated in the study. Sputum and bronchial aspirate were assessed according to traditional methods on Löwenstein-Jensen medium, and bronchoalveolar lavage (BAL) was assessed by the LCx test and the Bactec 460 system. Another 30 patients with non-tuberculous infections were included in the study as controls.RESULTS: Of the 30 patients suspected of tuberculosis, 19 had active disease on clinical, bacteriological and radiographic grounds, nine inactive tuberculosis and two had lung cancer. Bacteriological confirmation was obtained in 12 of the 19 (63.2%) patients with active tuberculosis. The sensitivity of sputum culture was 42.1% and bronchial aspirate culture 47.4%. BAL fluid revealed positive results in 57.9% using both LCx and Bactec. The results of the LCx assay can be obtained in 5 hours as opposed to several weeks using other methods.CONCLUSION: The LCx test may be useful in the diagnosis of smear-negative pulmonary tuberculosis and may be recommended in these clinical situations.