Table 3.
Trends of antimicrobial resistance of Gram-positive and Gram-negative bacteria.
| Number of resistant isolates/total isolates tested (proportion) within the year | |||||||
| Microorganisms | 2002 | 2003 | 2004 | 2 005 | 2002/2003 | 2004/2005 | p-value** |
| Gram-positive | |||||||
| Staphylococcus epidermidis | |||||||
| Oxacillin | 171/202 (84.7) | 215/261 (82.4) | 179/219 (81.2) | 75/94 (79.8) | 386/463 (83.3%) | 254/313 (81.2%) | 0.10 |
| Gentamicin | 144/202 (71.3) | 168/261 (64.4) | 148/219 (67.6) | 54/94 (57.5) | 312/463 (67.4%) | 202/313 (64.5%) | 0.37 |
| Vancomycin | 0/202 (0) | 0/261 (0) | 0/219 (0) | 0/94 (0) | 0/463 (0%) | 0/313 (0%) | NA |
| Staphylococcus aureus | |||||||
| Oxacillin | 25/38 (65.8) | 21/30 (70) | 12/25 (48) | 6/8 (75) | 46/68 (67.6%) | 18/33 (54.5%) | 0.19 |
| Gentamicin | 23/38 (60.5) | 4/30 (13.3) | 6/25(24) | 3/8 (37.5) | 27/68 (39.7%) | 9/33 (27.3%) | 0.22 |
| Vancomycin | 0/38 (0) | 0/30 (0) | 0/25 (0) | 0/8 (0) | 0/68 (0%) | 0/33 (0%) | 1 |
| Enterococcus faecalis | |||||||
| Vancomycin | 0/14 (0) | 2/19 (10.5) | 0/7 (0) | 0/4 (0) | 2/33 (6.1%) | 0/11 (0%) | 1 |
| Enterococcus faecium | |||||||
| Vancomycin | 1/15 (6.7) | 0/8 (0) | 3/11 (27.3) | 0/2 (0) | 1/22 (4.5%) | 3/13 (23.1%) | 0.13 |
| Gram negative | |||||||
| Acinetobacter baumannii | |||||||
| Amikacin | 6/9 (66.6) | 10/15 (66.6) | 32/35 (91.4) | 15/17 (88.2) | 16/24 (66.7%) | 47/52 (90.4%) | 0.019 |
| Ceftazidime | 8/9 (88.8) | 13/15 (86.6) | 34/35 (97.1) | 17/17 (100) | 21/24 (87.5%) | 51/52 (98.1%) | 0.09 |
| Ciprofloxacin | 6/9 (66.6) | 11/15 (73.3) | 34/35 (97.1) | 17/17 (100) | 17/24 (70.8%) | 51/52 (98.1%) | 0.001 |
| Colistin | 1/9 (11.1) | 0/15 (0) | 0/35 (0) | 1/17 (5.8) | 0/24 (0%) | 1/52 (0%) | 1 |
| Gentamicin | 4/9 (44.4) | 10/15 (66.6) | 16/35 (45.7) | 12/17 (70.5) | 14/24 (58.3%) | 28/52 (53.8%) | 0.71 |
| Imipenem | 4/9 (44.4) | 8/15 (53.3) | 34/35 (97.1) | 17/17 (100) | 12/24 (50%) | 51/52 (98.1%) | <0.001 |
| Piperacillin/Tazobactam | 7/9 (77.7) | 12/15 (80) | 34/35 (97.1) | 17/17 (100) | 19/24 (79.2%) | 51/52 (98.1%) | 0.01 |
| Pseudomonas aeruginosa | |||||||
| Amikacin | 15/32 (46.9) | 15/33 (45.5) | 17/25 (68) | 4/11 (36.4) | 30/65 (46.2%) | 21/36 (58.3%) | 0.24 |
| Ceftazidime | 18/32 (56.3) | 19/33 (57.6) | 21/25 (84) | 8/11 (72.7) | 37/65 (56.9%) | 29/36 (80.6%) | 0.016 |
| Ciprofloxacin | 20/32 (62.5) | 14/33 (42.4) | 17/25 (68) | 5/11 (45.4) | 34/65 (52.3%) | 22/36 (61.1%) | 0.39 |
| Colistin | 0/32 (0) | 0/33 (0) | 0/25 (0) | 0/11 (0) | 0/65 (0%) | 0/36 (0%) | 1 |
| Imipenem | 20/32 (62.5) | 14/33 (42.4) | 15/25 (60) | 5/11 (45.4) | 34/65 (52.3%) | 20/36 (55.5%) | 0.75 |
| Piperacillin/Tazobactam | 3/32 (9.4) | 7/33 (21.2) | 18/25 (72) | 2/11 (18.2) | 10/65 (15.4%) | 20/36 (55.5%) | 0.10 |
| Klebsiella pneumoniae | |||||||
| Ceftazidime | 2/7 (28.6) | 11/34 (32.4) | 15/29 (51.7) | 9/11 (81.8) | 13/41 (31.7%) | 24/40 (60%) | 0.010 |
| Ciprofloxacin | 1/7 (14.3) | 12/34 (35.3) | 16/29 (55.2) | 4/11 (36.4) | 13/41 (31.7%) | 20/40 (50%) | 0.006 |
| Meropenem | 0/7 (0) | 1/34 (2.9) | 8/29 (27.6) | 9/11 (81.8) | 1/41 (2.4%) | 17/40 (42.5%) | <0.001 |
| Cefepime | 0/7 (0) | 11/34 (32.4) | 15/29 (51.7) | 9/11 (81.8) | 11/41 (26.8%) | 24/40 (60%) | <0.001 |
| Cefoxitin | 0/7 (0) | 10/34 (29.4) | 18/29 (62.1) | 9/11 (81.8) | 10/41 (24.4%) | 27/40 (67.5%) | <0.001 |
| Tobramycin | 0/7 (0) | 8/34 (23.5) | 17/29 (58.6) | 9/11 (81.8) | 8/41 (19.5%) | 26/40 (65%) | <0.001 |
| Piperacillin/Tazobactam | 0/7 (0) | 8/34 (23.5) | 15/29 (51.7) | 9/11 (81.8) | 8/41 (19.5%) | 24/40 (60%) | <0.001 |
| Escherichia coli | |||||||
| Amikacin | 0/35 (0) | 0/57 (0) | 4/47(8.5) | 1/30(0) | 0/92 (0%) | 5/77 (6.5%) | 0.05 |
| Ciprofloxacin | 7/35 (0.2) | 3/57 (5.2) | 4/47(8.5) | 9/30(30) | 10/92 (10.9%) | 13/77 (16.9%) | 0.006 |
| Piperacillin/Tazobactam | 1/35 (2.8) | 1/57 (1.7) | 4/47(8.5) | 2/30(6.6) | 2/92 (2.2%) | 6/77 (7.8%) | 0.37 |
| Ceftazidime | 2/35 (5.7) | 0/57 (0) | 4/47(8.5) | 5/30(16.6) | 2/92 (2.2%) | 9/77 (11.7%) | 0.02 |
| Cefoxitin | 4/35 (11.4) | 1/57 (1.7) | 4/47(8.5) | 4/30(13.3) | 5/92 (5.4%) | 8/77 (10.4%) | 0.18 |
| Meropenem | 1/35 (2.8) | 0/57 (0) | 1/47(2.1) | 0/30(0) | 1/92 (1.1%) | 1/77 (1.3%) | 0.52 |
* Data for the year 2005 refer to the period from January 2005 through June 2005.
** P-values refer to the comparison of proportions between 2002/2003 and 2004/2005.