Table 2.
Phenotypic susceptibility and genotypic characterization of M. tuberculosis isolates with disputed rpoB mutations
| Isolate | Culture | Clinical | Phenotypic resistance | Susceptibility | Mutations detected inc | embB | pncA | Spoligotyping | Final resistance | ||
|---|---|---|---|---|---|---|---|---|---|---|---|
| no. | no. | specimen | to anti-TB drugsb | to PZAb | rpoB | katG315 | inhA-RR | mutation | mutation | lineage | pattern |
| D1 | 5853/05 | BALa | INH + SM | Not done | H526N | S315 T | None | None | None | Orphan | INH + SM + RIF |
| D2 | 13,242/10 | Sputum | INH + EMB | Not done | D516Y | S315 T | None | M306 V | R2Pd | EAI5/EAI3 | INH + EMB + RIF + PZA |
| D3 | 10,268/11 | Pleural fluid | INH + SM | Resistant | H526N | S315 T | None | M306 V | H51P | Orphan | INH + SM + PZA + RIF + EMB |
| D4 | 13,341/16 | Sputum | INH + SM + EMB | Susceptible | S531C | S315 T | None | M306 V | None | T1 Uganda | INH + SM + EMB + RIF |
INH, isoniazid; SM, streptomycin; EMB, ethambutol; RIF, rifampicin, PZA, pyrazinamide
HSR-rpoB, 81-base pair hot-spot region of rpoB gene; katG315, katG codon 315; inhA-RR, upstream regulatory region of inhA gene
aBAL, bronchoalveolar lavage
bThe susceptibility to anti-TB drugs was determined by MGIT 960 system
cMutations in rpoB, katG codon 315 and inhA-regulatory region were detected by GenoType MTBDRplus assay and/or PCR-sequencing of respective loci
dRepresents a novel mutation not described previously