Table 2.
Clinical outcomes of the matched population
| Variables | Matched population (N = 122) | Cases and controlsa | ||
|---|---|---|---|---|
| Cases (N = 61) | Controls (N = 61) | P value | ||
| CZA MIC increase [CZA resistance development], n (%) | 6 (4.9) [2 (33.0)] | 3 (4.9) [0] | 3 (4.9) [2 (66.0)] | 0.185 |
| Early clinical improvement,bn (%) | 98 (80.3) | 52 (85.2) | 46 (75.4) | 0.255 |
| Clinical cure,cn (%) | 83 (68.0) | 46 (75.4) | 37 (60.7) | 0.120 |
| KPC-Kp BSI recurrence,dn (%) | 10 (8.2) | 4 (6.6) | 6 (9.8) | 0.509 |
| New KPC-Kp infection (BSI excluded),en (%) | 13 (10.7) | 3 (4.9) | 10 (16.4) | 0.039 |
| Source of new KPC-Kp infection, n (%) | ||||
| Urinary tract | 9 (69.2) | 3 (100.0) | 6 (60.0) | 0.332 |
| Intra-abdominal | 1 (7.7) | 0 | 1 (10.0) | |
| Lower respiratory tract | 2 (15.4) | 0 | 2 (20.0) | |
| Bone and joint | 1 (7.7) | 0 | 1 (10.0) | |
| Secondary infections,fn (%) | 42 (34.4) | 17 (27.9) | 25 (41.0) | 0.182 |
| Source of secondary infection, n (%) | ||||
| Urinary tract | 6 (14.3) | 2 (11.8) | 4 (16.0) | 0.746 |
| Intra-abdominal | 1 (2.4) | 0 | 1 (4.0) | |
| Lower respiratory tract | 4 (9.5) | 1 (5.9) | 3 (12.0) | |
| C. difficile | 4 (9.5) | 1 (5.9) | 3 (12.0) | |
| Bacteraemia | 17 (40.5) | 9 (52.9) | 8 (32.0) | |
| Candidaemia | 10 (23.8) | 4 (23.5) | 6 (24.0) | |
| Negative KPC-Kp FUBCs 72 h after treatment start, n (%) [performed in n (%)] | 68 (85.0) [80 (65.8)] | 33 (76.7) [43 (70.5)] | 35 (94.6) [37 (60.7)] | 0.026 |
| Negative KPC-Kp FUBCs 7 days after treatment start, n (%) [performed in n (%)] | 58 (92.1) [63 (51.6)] | 30 (88.2) [34 (55.7)] | 28 (96.6) [29 (47.5)] | 0.224 |
| Negative KPC-Kp FUBCs 14 days after treatment start, n (%) [performed in n (%)] | 42 (93.3) [45 (36.9)] | 25 (96.2) [26 (42.6)] | 17 (89.5) [19 (31.2)] | 0.375 |
| Cumulative mortality at 7 days from BSI onset, n (%) | 6 (4.9) | 3 (4.9) | 3 (4.9) | 1.0 |
| Cumulative mortality at 14 days from BSI onset, n (%) | 11 (9.0) | 6 (9.8) | 5 (8.2) | 0.752 |
| Cumulative mortality at 30 days from BSI onset, n (%) | 20 (16.4) | 9 (14.8) | 11 (18.0) | 0.807 |
| Overall in-hospital mortality, n (%) | 39 (32.0) | 20 (32.8) | 19 (31.1) | 1.0 |
| Death associated to secondary infection (KPC-Kp excluded), n (%) | 8 (6.6) | 1 (1.6) | 7 (11.5) | 0.020 |
| Length of stay from BSI onset (days), median (IQR) | 29 (15–47) | 28 (14–48) | 29 (16–47) | 0.544 |
CZA, ceftazidime/avibactam. Bold type indicates statistical significance.
Cases were patients with KPC-Kp BSI receiving CZA + FOF; controls were patients with KPC-Kp BSI receiving CZA alone or in combination with in vitro non-active drugs different from FOF (CZA ± other).
Early (within 48–72 h) clinical improvement was defined as at least one of the following: weaning from vasopressors; fever disappearance >48 h; procalcitonin reduction by >80%; C-reactive protein reduction by >75%.
Clinical cure was defined as clinical response to treatment with resolution of symptoms/signs of the infection upon discontinuation of antimicrobials.
KPC-Kp BSI recurrence was defined as the onset of a second microbiologically documented KPC-Kp BSI in a patient who had previously achieved clinical cure.
New, non-bacteraemic KPC-Kp infection was considered as isolation of KPC-Kp causing infections other than BSI after achieving clinical cure.
Secondary infection was defined as an infection (i.e. UTI, pneumonia, bacteraemia, candidaemia) caused by a microorganism other than KPC-Kp in the 30 days after the start of treatment.