TABLE 4.
AST performance for Gram-negative organisms (pre-discrepancy testing) for the 87 analyzable runs
| Organisma | Drugb | Category agreement [no./total (%)] | No. of errors |
||
|---|---|---|---|---|---|
| Very major | Major | Minor | |||
| ABA (n = 1) | AMK | 1/1 (100) | 0 | 0 | 0 |
| CIT, ENT, and SMA (n = 12) | AMK | 12/12 (100) | 0 | 0 | 0 |
| ATM | 10/12 (83.3) | 1 | 1 | 0 | |
| CAZ | 5/12 (41.7) | 1 | 2 | 4 | |
| FEP | 12/12 (100) | 0 | 0 | 0 | |
| CRO | 10/12 (83.3) | 0 | 0 | 2 | |
| CIP | 12/12 (100) | 0 | 0 | 0 | |
| ETP | 12/12 (100) | 0 | 0 | 0 | |
| GEN | 12/12 (100) | 0 | 0 | 0 | |
| MEM | 12/12 (100) | 0 | 0 | 0 | |
| TZP | 6/12 (50) | 1 | 0 | 5 | |
| TOB | 12/12 (100) | 0 | 0 | 0 | |
| ECO, KLE, and PRO (n = 64) | AMK | 63/64 (98.4) | 0 | 0 | 1 |
| SAM | 54/62 (87.1) | 0 | 0 | 8 | |
| ATM | 60/64 (93.8) | 1 | 0 | 3 | |
| CAZ | 59/63 (93.7) | 0 | 0 | 4 | |
| FEP | 61/64 (95.3) | 2 | 0 | 1 | |
| CRO | 64/64 (100) | 0 | 0 | 0 | |
| CIP | 63/64 (98.4) | 0 | 0 | 1 | |
| ETP | 64/64 (100) | 0 | 0 | 0 | |
| GEN | 64/64 (100) | 0 | 0 | 0 | |
| MEM | 62/63 (98.4) | 0 | 0 | 1 | |
| TZP | 59/64 (92.2) | 2 | 0 | 3 | |
| TOB | 60/63 (95.2) | 0 | 0 | 3 | |
| PAE (n = 10) | AMK | 10/10 (100) | 0 | 0 | 0 |
| CAZ | 6/10 (60) | 0 | 0 | 4 | |
| FEP | 8/10 (80) | 0 | 0 | 2 | |
| CIP | 8/10 (80) | 0 | 0 | 2 | |
| GEN | 10/10 (100) | 0 | 0 | 0 | |
| MEM | 5/10 (50) | 0 | 0 | 5 | |
| TZP | 5/10 (50) | 0 | 0 | 5 | |
| TOB | 10/10 (100) | 0 | 0 | 0 | |
| All Gram-negative organisms (n = 87) | AMK | 86/87 (98.9) | 0 | 0 | 1 |
| SAM | 54/62 (87.1) | 0 | 0 | 8 | |
| ATM | 70/76 (92.1) | 2 | 1 | 3 | |
| CAZ | 70/85 (82.4) | 1 | 2 | 12 | |
| FEP | 81/86 (94.2) | 2 | 0 | 3 | |
| CRO | 74/76 (97.4) | 0 | 0 | 2 | |
| CIP | 83/86 (96.5) | 0 | 0 | 3 | |
| ETP | 76/76 (100) | 0 | 0 | 0 | |
| GEN | 86/86 (100) | 0 | 0 | 0 | |
| MEM | 79/85 (92.9) | 0 | 0 | 6 | |
| TZP | 70/86 (81.4) | 3 | 0 | 13 | |
| TOB | 82/85 (96.5) | 0 | 0 | 3 | |
| Overall performance | 911/976 (93.3) | 8 | 3 | 54 | |
a
ABA, Acinetobacter baumannii; CIT, Citrobacter spp.; ECO, Escherichia coli; KLE, Klebsiella spp.; PRO, Proteus spp.; PAE, Pseudomonas aeruginosa; SMA, Serratia marcescens.
b
AMK, amikacin; SAM, ampicillin-sulbactam; ATM, aztreonam; CAZ, ceftazidime; FEP, cefepime; CRO, ceftriaxone; CIP, ciprofloxacin; ETP, ertapenem; GEN, gentamicin; MEM, meropenem; TZP, piperacillin-tazobactam; TOB, tobramycin.