PT  - JOURNAL ARTICLE
AU  - Carolin Kreiter
AU  - Anna Streubel
AU  - Andreas Roth
AU  - Nicolas Schönfeld
AU  - Torsten Blum
AU  - Lena Bös
AU  - Ralf Otto-Knapp
AU  - Harald Mauch
AU  - Holger Rüssmann
AU  - Torsten T. Bauer
TI  - Direct molecular testing for isoniazid and rifampicin resistance from respiratory specimens of patients with tuberculosis
DP  - 2013 Sep 01
TA  - European Respiratory Journal
PG  - P4480
VI  - 42
IP  - Suppl 57
4099  - http://erj.ersjournals.com/content/42/Suppl_57/P4480.short
4100  - http://erj.ersjournals.com/content/42/Suppl_57/P4480.full
SO  - Eur Respir J2013 Sep 01; 42
AB  - Introduction: With the emergence of MDR-TB the therapy of TB faces a new challenge. In order to detect resistances more rapidly, new molecular testing systems for the analysis of TB as well as the resistances against its first line drugs have gained focus of scientific interest.Aims: This study evaluated the benefit of direct molecular testing for INH and RMP resistance from respiratory materials compared to conventional cultural-based methods.Methods: Between 2010 and 2012, respiratory specimens of patients with suspected TB who finally turned out to be culture positive, were primarily tested by PCR for mutations in the rpoB- and katG-genes. Results of the direct molecular testing were retrospectively analysed for feasibility and compared to those routinely obtained by conventional culture-based methods.Results: 34 out of the 38 tested patients with a positive TB-culture were also smear-positive. With the cultural analysis we found an INH-, RMP-, and a combined INH-/ RMP-resistance in 8, 4, and 4 cases, respectively. 7 of the 8 INH-resistant patients were smear-positive, 1 was smear-negative.With regard to the 3 remaining patients who were smear-negative, the molecular resistance testing already led to results before culture results were available (2 INH and RMP susceptible, 1 INH resistant). In 2 cases, results of molecular testing differed from results of cultural derived resistance. In these cases the molecular testing failed to show the gene-mutation (1 INH-resistance, 1 RMP-resistance).Conclusion: Direct molecular resistance testing from respiratory specimens is feasible and enables early detection of first line drug resistances in TB-patients.