TABLE 6.
Correlational analysis of biofilm phage susceptibility and oxacillin, linezolid, rifampin, daptomycin, clindamycin, and levofloxacin susceptibilitya
| Antibiotic | No. of antibiotic- susceptible isolates | No. of antibiotic intermediate isolates | No. of antibiotic- resistant isolates | Phage | P value |
|---|---|---|---|---|---|
| Oxacillin | 18 | NA | 7 | ATCC 11988-B1 | 0.3047 |
| 48 | NA | 26 | ATCC 19685-B1 | 0.6044 | |
| 42 | NA | 15 | ATCC 23360-B1 | 0.8444 | |
| Clindamycin | 16 | NA | 9 | ATCC 11988-B1 | 0.2620 |
| 52 | NA | 21 | ATCC 19685-B1 | 0.9879 | |
| 40 | NA | 17 | ATCC 23360-B1 | 0.1331 | |
| Rifampin | 25 | NA | 0 | ATCC 11988-B1 | NA |
| 72 | NA | 2 | ATCC 19685-B1 | 0.2638 | |
| 56 | NA | 1 | ATCC 23360-B1 | 0.5243 | |
| Daptomycin | 11 | NA | 0 | ATCC 11988-B1 | NA |
| 35 | NA | 0 | ATCC 19685-B1 | NA | |
| 24 | NA | 0 | ATCC 23360-B1 | NA | |
| Levofloxacin | 10 | 8 | 7 | ATCC 11988-B1 | 0.5772b |
| 29 | 22 | 23 | ATCC 19685-B1 | 0.4102b | |
| 23 | 18 | 16 | ATCC 23360-B1 | 0.7386b | |
| Linezolid | 12 | NA | 0 | ATCC 11988-B1 | NA |
| 24 | NA | 0 | ATCC 19685-B1 | NA | |
| 25 | NA | 0 | ATCC 23360-B1 | NA |
a
The Wilcoxon rank sum test with normal approximation was performed to assess correlation between oxacillin, linezolid, rifampin, daptomycin, clindamycin, or levofloxacin susceptibility and biofilm phage response as measured by percent reduction under treated versus control conditions in biological replicates, α = 0.05. NA, not applicable.
b
Kruskal-Wallis test with chi square approximation was performed to accommodate nonbinary levofloxacin susceptibility data.