Pneumologie 2007; 61 - V306
DOI: 10.1055/s-2007-973116

Rapid diagnosis of smear negative tuberculosis by bronchoalveolar-lavage enzyme-linked immunospot: an update

C Jafari 1, M Ernst 2, B Kalsdorf 1, U Greinert 1, D Kirsten 3, A Lalvani 4, C Lange 1
  • 1Clinical Infectious Disease, Medical Clinic, Research Center Borstel
  • 2Immunecell analytics, Research Center Borstel
  • 3Hospital Großhansdorf, Center for Pulmonary Medicine and Thoracic Surgery
  • 4Tuberculosis Immunology Group, Nuffield Department of Clinical Medicine, John Radcliff Hospital, University of Oxford

Aims: In patients with active pulmonary tuberculosis (pTB) with negative acid-fast-bacilli (AFB)-smear results for sputum and bronchial secretions the clinical diagnosis of tuberculosis is often delayed. In an exploratory study (Jafari et al. AJRCCM 2006) with 37 patients we found that ELISPOT performed on mononuclear cells from the bronchoalveolar-lavage (BAL) allows a rapid diagnosis of tuberculosis in these cases. We here present a follow up of 72 prospectively recruited cases with a presumptive diagnosis of smear-negative pTB.

Methods: Patients presenting to a tertiary hospital with a medical history and a pulmonary infiltrate compatible with tuberculosis and 3 negative AFB-smear results from the sputum were prospectively enrolled in this study. A MTB-specific ELISPOT (T-SPOT.TB) with ESAT-6 and CFP-10 peptides was performed on peripheral blood mononuclear cells (PBMCs) and mononuclear cells from the BAL (BALMCs).

Results: Among 20 patients with pTB one patient had a negative ELISPOT test result from the BAL. Among 52 patients with an alternative diagnosis, 4 had a positive ELISPOT test result from the BAL. Sensitivity and specificity of the MTB-specific ELISPOT performed on BALMCs was 95 percent and 92.3 percent, respectively.

Conclusions: Smear negative pulmonary tuberculosis can rapidly be diagnosed by identification of MTB-specific cells in the BAL.