RT Journal Article SR Electronic T1 Range of additional drug resistance of M.tuberculosis in XDR-TB patients JF European Respiratory Journal JO Eur Respir J FD European Respiratory Society SP PA2677 DO 10.1183/13993003.congress-2016.PA2677 VO 48 IS suppl 60 A1 Vasilyeva Anatolievna, Irina A1 Samoilova, Anastasia A1 Chernousova, Larisa A1 Bagdasaryan, Tatev A1 Testov, Vadim YR 2016 UL http://erj.ersjournals.com/content/48/suppl_60/PA2677.abstract AB Introduction: Additional DR of M. tuberculosis (MBT) among XDR-TB patients complicates the selection of 6 effective TB drugs for treatment.Objective: To study DR of MBT to 11 TB drugs among XDR-TB patients.Materials and methods: 164 previously treated XDR-TB patients were included in the study. Of them, 119 (72.6%) previously used second-line TB drugs. DSTs by the absolute concentrations method and BACTEC MGIT 960 were performed to the isoniazid (H), rifampicin (R), ethambutol (E), streptomycin (S), pyrazinamide (Z) and amikacin (Am)/kanamycin (Km), capreomycin (Cm), ofloxacin (Ofx)/levofloxacin (Lfx), protionamid (Pto), aminosalicylic acid (PAS), cycloserine (Cs).Results: On average, XDR-TB patients had DR to 7.68 (Mo=9.0; Me=8.0) TB drugs. All patients had DR to H, R, S and Ofx or Lfx and to one of the injection drugs, such as Am, Km or Cm. Resistance to the drugs, both from a group of aminoglycosides and polypeptides, was reported in 72 patients (43.9%), 28 patients (17.1%) had DR only to polypeptides and 64 patients (39%) - only to aminoglycosides.Resistance to E was reported in 124 patients (75/6%); 67 out of 140 patients (47.8%) were resistant to Z. Resistance to the second-line TB drugs among XDR-TB patients was as follows: 103 patients (62.8%) were resistant to Pto, 35 (21.3%) - to Cs, and 26 (15.9%) - to PAS.Conclusion: On average, XDR-TB patients had DR to 7.68 (Mo=9.0; Me =8.0) TB drugs. Resistance to Cm was reported in 60.9 % of XDR-TB patients. Of them, 17.1% had sensitivity of MBT to Km/Am. Additional DR among XDR-TB patients was observed most frequently to E (75.6%), Pto (62.8%), Z (47.8%).