Table 1. In vitro antibiotic susceptibility profiles of AUST-02 isolates (n = 134).
| Antibiotic | Susceptibility profile number* | ||||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | |
| Ciprofloxacin | S | R | I | R | S | I | S | S | I | R | S | I | I | I | I | R | I | R | I |
| Tobramycin | S | S | R | R | R | S | I | S | I | I | S | S | S | S | I | S | R | I | S |
| Amikacin | R | R | R | R | R | R | R | I | R | R | R | S | I | R | R | S | R | R | R |
| Aztreonam | R | R | R | R | R | R | R | R | R | R | R | S | R | I | R | R | R | R | R |
| Ceftazidime | R | R | R | R | R | R | R | R | R | R | R | S | R | R | R | R | R | R | R |
| Cefepime | R | R | R | R | R | R | R | R | R | R | S | R | R | R | R | R | R | R | S |
| Imipenem | R | R | R | R | R | R | R | R | R | R | R | S | R | R | R | R | R | R | R |
| Meropenem | R | R | R | R | R | R | R | R | R | R | R | S | R | R | S | R | R | R | I |
| Ticarcillin/clavulanate | R | R | R | R | R | R | R | R | R | R | R | S | R | R | R | R | R | R | R |
| Colistin sulphateII | S | S | S | S | S | S | S | S | S | S | S | S | S | S | S | S | S | S | R |
| Polymyxin BII | S | S | S | S | S | S | S | S | S | S | S | S | S | S | S | S | R | R | R |
| Isolates at each time-point; no. | |||||||||||||||||||
| Day 1 | 28‡ | 1 | 3‡ | 2 | 0 | 3 | 3 | 1 | 2 | 1 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 1 |
| Day 7 | 4 | 1 | 3‡ | 2 | 1 | 1 | 0 | 1 | 0 | 0 | 0 | 0 | 1 | 1‡ | 0 | 0 | 0 | 0 | 0 |
| Day 14 | 0 | 10‡ | 5 | 10‡ | 6 | 2 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 1 | 1 | 1 | 0 |
| Day 23 | 3‡ | 4‡ | 5 | 1‡ | 5 | 4 | 2 | 0 | 0 | 1 | 0 | 1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Outpatient follow-up | 0 | 3 | 0 | 1 | 3 | 1‡ | 0 | 1 | 0 | 0 | 1‡ | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Total number of isolates; no. (%) | 35 | 19 | 16 | 16 | 15 | 11 | 6 | 3 | 2 | 2 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
| (26) | (14) | (12) | (12) | (11) | (8) | (4) | (2) | (1.5) | (1.5) | (1) | (1) | (1) | (1) | (1) | (1) | (1) | (1) | (1) | |
| Isolates selected for WGS | AUS960 | AUS963 | AUS959 | AUS964 | AUS968 | AUS967 | AUS962 | ||||||||||||
| AUS965 | AUS969† | AUS961 | AUS966 | ||||||||||||||||
*Breakpoints defined by the Clinical and Laboratory Standards Institute [21]
†The sequenced M3L43 isolate (isolate ID, AUS969) was derived from the M3L7 sub-type having acquired an additional SNP in the lasR gene (S1 Table)
‡Isolates selected for WGS from these time-points
IIChromosomally encoded genes associated with polymyxin resistance were not investigated as all isolates sequenced were classed as susceptible to colistin sulphate and polymyxin B; antibiotic susceptibilities in bold, greatest phenotypic diversity observed.
Abbreviations: R, resistant; I, intermediate resistant; S, susceptible; WGS, whole-genome sequencing.