Table 1.
Demographic and Clinical Characteristics of Study Patients
| Characteristics | CAZ-AVI n = 149 | IV Colistin n = 81 | P value |
|---|---|---|---|
| Demographic | |||
| Age in years (mean ± SD) | 59 ± 18 | 57.5 ± 20 | 0.474 |
| Male, n (%) | 93 (62) | 50 (61) | 0.918 |
| Study site | |||
| KFMC | 48 (32) | 33 (41) | 0.196 |
| KAMC | 39 (26) | 20 (25) | 0.806 |
| KFSHRC | 24 (16) | 9 (11) | 0.302 |
| KSUMC | 17 (12) | 10 (12) | 0.833 |
| SFH | 21 (14) | 9 (11) | 0.521 |
| Comorbidity, n (%) | |||
| AIDS | 1 (0.7) | 1 (1) | 0.660 |
| Cerebrovascular disease | 43 (29) | 19 (23) | 0.378 |
| Chronic heart failure | 24 (16) | 5 (6) | 0.030 |
| Chronic obstructive pulmonary disease | 10 (7) | 3 (4) | 0.345 |
| Connective tissue disease | 8 (5) | 1 (1) | 0.122 |
| Dementia | 11 (7) | 2 (2) | 0.123 |
| Diabetes mellitus | 71 (48) | 47 (58) | 0.133 |
| Endocrine disorder# | 46 (31) | 23 (28) | 0.695 |
| Hemiplegia or paraplegia | 13 (9) | 4 (5) | 0.294 |
| History of myocardial infarction | 17 (11) | 7 (9) | 0.512 |
| Hypertension | 89 (60) | 48 (59) | 0.944 |
| Immunosuppressed† | 33 (22) | 16 (20) | 0.672 |
| Liver disease | 14 (9) | 4 (5) | 0.229 |
| Moderate to severe chronic renal failure | 34 (23) | 14 (17) | 0.324 |
| Neurological disease | 34 (23) | 13 (16) | 0.224 |
| Peptic ulcer disease | 7 (5) | 2 (2) | 0.405 |
| Peripheral vascular disease | 13 (9) | 1 (1) | 0.023 |
| Charlson comorbidity index, median (IQR) | 5 (3–7) | 4 (2–6) | 0.013 |
| Baseline serum creatinine in µmol/L, median (IQR) | 94 (57–160) | 73 (44–130) | 0.032 |
| Baseline creatinine clearance in mL/min, median (IQR) | 60 (33–99) | 75 (36–120) | 0.112 |
| Indwelling invasive devices, n (%) | |||
| Central venous catheter | 77 (52) | 33 (41) | 0.113 |
| Foley catheter | 93 (62) | 42 (52) | 0.120 |
| Mechanical ventilation | 76 (51) | 35 (43) | 0.258 |
| Severity of illness, n (%) | |||
| Intensive care unit at infection onset | 93 (62) | 53 (65) | 0.650 |
| No sepsis | 20 (13) | 11 (14) | 0.973 |
| Sepsis | 90 (61) | 51 (63) | 0.703 |
| Septic shock | 39 (26) | 19 (23) | 0.650 |
| APACHE II score, median (IQR) | 16 (11–20) | 15 (11–19) | 0.327 |
| Site of infection, n (%) | |||
| HAP | 40 (27) | 20 (25) | 0.722 |
| UTI | 30 (20) | 14 (17) | 0.600 |
| Wound | 24 (16) | 13 (16) | 0.991 |
| Intraabdominal | 21 (14) | 9 (11) | 0.521 |
| VAP | 13 (9) | 9 (11) | 0.557 |
| CLABSI | 5 (3) | 3 (4) | 0.891 |
| Other | 16 (11) | 13 (16) | – |
| Presence of bacteremia, n (%) | 43 (29) | 17 (21) | 0.194 |
| Type of CRE, n (%) | |||
| Klebsiella pneumoniae | 136 (91) | 65 (80) | 0.016 |
| E. coli | 9 (6) | 12 (15) | 0.027 |
| Other | 4 (3) | 4 (5) | – |
| Polymicrobial infection, n (%) | 69 (46) | 34 (42) | 0.528 |
| Infectious diseases consultation, n (%) | 144 (97) | 76 (94) | 0.317 |
| Time to active therapy in hours, median (IQR) | 48 (20–79) | 43 (32–67) | 0.945 |
| Time to study drug in hours, median (IQR) | 60 (48–99) | 57 (24–90) | 0.142 |
| Combination therapy, n (%)* | 34 (23) | 57 (70) | < 0.001 |
| Combination with more than one agent, n (%) | 0 | 15 (19) | – |
| Type of combination therapy | |||
| Aminoglycoside | 7 (5) | 6 (7) | |
| Aztreonam | 3 (2) | 0 | |
| Carbapenem | 0 | 47 (58) | |
| Cephalosporin | 0 | 2 (3) | |
| Fluoroquinolone | 5 (3) | 3 (4) | |
| Inhaled colistin | 3 (2) | 0 | |
| Piperacillin/tazobactam | 0 | 6 (7) | |
| Tigecycline | 16 (11) | 8 (10) | |
| Susceptible to at least one combination agent, n (%) ± | 13 (38) | 16 (28) | 0.314 |
| Duration of therapy in days, median (IQR) | 12 (8–19) | 11 (7–17) | 0.213 |
| Overall duration of hospitalization in days, median (IQR) | 60 (30–90) | 62 (34–124) | 0.121 |
| Years of use during the study period | 2017–2020 | 2015–2020 | - |
Notes: #Any endocrine disorder except diabetes. †Neutropenic, chronic treatment with corticosteroids, active chemotherapeutic management of malignancy, or solid organ/bone marrow transplant patients on immunosuppressant therapy. *Given concurrently with the study drug for at least 48 hours. ±Denominator represents patients who received combination therapy.
Abbreviations: AIDS, acquired immunodeficiency syndrome; APACHE II, Acute Physiology and Chronic Health Evaluation; CAZ/AVI, ceftazidime/avibactam; CLABSI, central line-associated bloodstream infection; CRE, carbapenem-resistant Enterobacterales; IQR, interquartile range; KAMC, King Abdulaziz Medical City; KFMC, King Fahad Medical City; KFSHRC, King Faisal Specialist Hospital and Research Center; KSUMC, King Saud University Medical City; SFH, Security Forces Hospital; HAP, hospital-acquired pneumonia; IV, intravenous; SD, standard deviation; UTI, urinary tract infection; VAP, ventilator-associated pneumonia.