Table 2.
Antimicrobial susceptibility and MICs of 71 Nocardia isolates in clinical infections in Henan China from 2017 to 2023
| Drugs Breakpoint | Species/complex, no. of strains (%)a | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| N.farcinica, | N.abscessus complex,16 (22.5)b | N. cyriacigeorgica, | N.amamiensis, | N.otitidiscaviarum, 5(7.0) | N. wallacei, | N. africana, | N.flavorosea, | N.puris, | N.pseudobrasiliensis, 1 (1.4) | N.rhamnosiphila, (1.4) | ||
| 19(26.8) | 13,(18.3) | 8(11.3) | 3(4.2) | 2(2.8) | 2 (2.8) | 1 (1.4) | ||||||
| TMP-SMX (S ≤ 2/38, R ≥ 4/76) | MIC50 | ≤ 0.25/4.75 | ≤ 0.25/4.75 | ≤ 0.25/4.75 | ≤ 0.25/4.75 | 0.5/9.5 | ≤ 0.25/4.75 | |||||
| MIC90 | 1/19 | 1/19 | 1/19 | 0.5/9.5 | 2/38 | 1/19 | ||||||
| S/R (%) | 100/0 | 100/0 | 100/0 | 100/0 | 100/0 | 100/0 | 100/0 | 100/0 | 100/0 | 100/0 | 100/0 | |
| Linezolid (S ≤ 8, ~) | MIC50 | ≤ 1 | ≤ 1 | ≤ 1 | ≤ 1 | ≤ 1 | ≤ 1 | |||||
| MIC90 | 2 | ≤ 1 | ≤ 1 | ≤ 1 | 2 | ≤ 1 | ||||||
| S/NS (%) | 100/0 | 100/0 | 100/0 | 100/0 | 100/0 | 100/0 | 100/0 | 100/0 | 100/0 | 100/0 | 100/0 | |
| Ciprofloxacin (S ≤ 1, R ≥ 4) | MIC50 | 1 | > 4 | > 4 | > 4 | 2 | 1 | |||||
| MIC90 | 4 | > 4 | > 4 | > 4 | 4 | 2 | ||||||
| S/I/R (%) | 78.9/10.5/10.5 | 18.8/18.8/62.5 | 0/0/100 | 0/0/100 | 20/40/40 | 66.7/33.3/0 | 0/50/50 | 100/0/0 | 0/0/100 | 0/0/100 | 100/0/0 | |
| Imipenem (S ≤ 4, R ≥ 16) | MIC50 | 8 | 4 | ≤ 2 | 4 | 64 | 8 | |||||
| MIC90 | 32 | 64 | 16 | 8 | > 64 | > 64 | ||||||
| S/I/R (%) | 26.3/26.3/47.4 | 50/0/50 | 61.5/23.1/15.4 | 75/25/0 | 0/0/100 | 33.3/33.3/33.3 | 0/0/100 | 100/0/0 | 100/0/0 | 0/100/0 | 100/0/0 | |
| Moxifloxacin (S ≤ 1, R ≥ 4) | MIC50 | 0.5 | 8 | 2 | 4 | 1 | ≤ 0.25 | |||||
| MIC90 | 2 | 16 | 4 | 8 | 2 | 1 | ||||||
| S/I/R (%) | 84.2/10.5/5.3 | 25/18.8/56.2 | 7.7/61.5/30.8 | 0/12.5/87.5 | 60/40/0 | 100/0/0 | 100/0/0 | 100/0/0 | 100/0/0 | 0/100/0 | 100/0/0 | |
| Cefepime | MIC50 | > 32 | 4 | 16 | 4 | > 32 | 4 | |||||
| MIC90 | > 32 | 16 | > 32 | > 32 | > 32 | 32 | ||||||
| Range | 16 to > 32 | ≤ 1 to 32 | 2 to > 32 | 2 to > 128 | ~ > 32 | 4 to 32 | ||||||
| AUG (S ≤ 8/4, R ≥ 32/16) | MIC50 | 8/4 | 16/8 | 16/8 | 16/8 | > 64/32 | 8/4 | |||||
| MIC90 | 16/8 | > 64/32 | 32/16 | 16/8 | > 64/32 | 16/8 | ||||||
| S/I/R (%) | 52.6/42.1/5.3 | 43.8/6.2/50 | 0/53.8/46.2 | 37.5/62.5/0 | 0/0/100 | 66.7/33.3/0 | 0/0/100 | 50/0/50 | 0/0/100 | 0/100/0 | 0/0/100 | |
| Amikacin (S ≤ 8, R ≥ 16) | MIC50 | ≤ 1 | ≤ 1 | ≤ 1 | ≤ 1 | ≤ 1 | 2 | |||||
| MIC90 | ≤ 1 | ≤ 1 | ≤ 1 | 2 | ≤ 1 | 16 | ||||||
| S/I/R (%) | 100/0/0 | 100/0/0 | 100/0/0 | 100/0/0 | 100/0/0 | 66.7/0/33.3 | 100/0/0 | 100/0/0 | 100/0/0 | 100/0/0 | 100/0/0 | |
| Ceftriaxone (S ≤ 8, R ≥ 64) | MIC50 | 64 | 4 | ≤ 4 | ≤ 4 | > 64 | 8 | |||||
| MIC90 | > 64 | 8 | 64 | 64 | > 64 | 32 | ||||||
| S/I/R (%) | 5.3/15.8/78.9 | 93.8/6.2/0 | 76.9/7.7/15.4 | 87.5/0/12.5 | 0/20/80 | 66.7/33.3/0 | 0/0/100 | 50/50/0 | 100/0/0 | 0/0/100 | 100/0/0 | |
| Doxycycline (S ≤ 1, R ≥ 8) | MIC50 | 2 | 0.12 | 2 | ≤ 0.12 | 1 | 2 | |||||
| MIC90 | 4 | 0.5 | 2 | 2 | 2 | 2 | ||||||
| S/I/R (%) | 26.3/73.7/0 | 93.8/6.2/0 | 46.2/53.8/0 | 87.5/12.5/0 | 60/40/0 | 0/100/0 | 0/100/0 | 50/50/0 | 100/0/0 | 0/0/100 | 100/0/0 | |
| Minocycline (S ≤ 1, R ≥ 8) | MIC50 | 2 | ≤ 1 | ≤ 1 | ≤ 1 | ≤ 1 | 2 | |||||
| MIC90 | 2 | ≤ 1 | 2 | ≤ 1 | 2 | 2 | ||||||
| S/I/R (%) | 36.8/63.2/0 | 93.8/6.2/0 | 61.5/38.5/0 | 100/0/0 | 80/20/0 | 33.3/66.7/0 | 50/50/0 | 50/50/0 | 100/0/0 | 0/0/100 | 100/0/0 | |
| Tobramycin (S ≤ 4, R ≥ 16) | MIC50 | 16 | ≤ 1 | ≤ 1 | ≤ 1 | 2 | > 16 | |||||
| MIC90 | > 16 | ≤ 1 | ≤ 1 | 8 | 4 | > 16 | ||||||
| S/I/R (%) | 5.3/15.8/78.9 | 100/0/0 | 100/0/0 | 87.5/12.5/0 | 100/0/0 | 33.3/0/66.7 | 100/0/0 | 100/0/0 | 100/0/0 | 100/0/0 | 100/0/0 | |
| Clarithromycin (S ≤ 2, R ≥ 8) | MIC50 | > 16 | 1 | 2 | 0.06 | 16 | 0.5 | |||||
| MIC90 | > 16 | > 16 | > 16 | 4 | > 16 | 16 | ||||||
| S/I/R (%) | 5.3/5.3/89.4 | 56.2/6.2/37.5 | 69.2/7.7/23.1 | 87.5/12.5/0 | 20/20/60 | 66.7/0/33.3 | 0/0/100 | 50/50/0 | 0/0/100 | 100/0/0 | 100/0/0 | |
| Cefoxitin | MIC50 | 64 | 8 | 64 | 16 | > 128 | 64 | |||||
| MIC90 | > 128 | 16 | > 128 | > 128 | > 128 | 128 | ||||||
| Range | 32 to > 128 | ≤ 4 to 128 | 16 to > 128 | ≤ 4 to > 128 | 128 to > 128 | 64 to 128 | ||||||
| Tigecycline | MIC50 | 0.5 | 0.25 | 0.25 | 0.06 | 0.25 | 0.25 | |||||
| MIC90 | 2 | 0.5 | 1 | 0.25 | 0.5 | 0.5 | ||||||
| Range | 0.03 to 4 | ≤ 0.015 to 1 | 0.12 to 1 | 0.03 to 0.25 | 0.06 to 0.5 | 0.25 to 0.5 | ||||||
Nocardia species/complex responsible for clinical infections in Henan China from 2017 to 2023. TMP-SMX, trimethoprim-sulfamethoxazole. AUG, Amoxicillin-clavulanic acid
S, susceptible; I, intermediate; R, resistant; NS, nonsusceptible; MIC50 and MIC90,MICs at which 50% and 90% of the strains were inhibited, respectively
The table shows the antimicrobial susceptibilities profifiles and MIC values (in mg/mL) (as determined by the broth microdilution method) to 15 antibiotics of the major
aPercentage with respect to the total number of identifified Nocardia strains (n = 71)
bN. abscessus complex (16) includes N. abscessus (8), N. asiatica (3), and N. beijingensis (5)