Background
Methods
Patient selection
Data collection and definition
Microbiology laboratory procedures
Serotyping and detection of hypermucoviscosity phenotype, aerobactin, and rmpA gene
Statistics
Results
Clinical characteristics of patients with bacteremic CAP due to K. pneumoniae
Characteristic |
K. pneumoniae
(n = 49) No. (%) |
S. pneumoniae
(n = 44) No. (%) |
p-value |
---|---|---|---|
Age, mean years ± SE | 73 ± 14 | 76 ± 11 | 0.893 |
Male sex | 39 (79.6) | 39 (88.6) | 0.236 |
Predisposing condition or risk factor | |||
Diabetes mellitus | 17 (34.7) | 11 (25) | 0.309 |
Malignancy | 14 (28.6) | 11 (25) | 0.698 |
Neurologic disorders | 12 (24.5) | 12 (27.3) | 0.759 |
Chronic kidney disease stage≧4 | 13 (26.5) | 13 (29.5) | 0.746 |
Chronic lung diseases | 23 (46.9) | 21 (47.7) | 0.939 |
Liver cirrhosis | 4 ( 8.2) | 3 ( 6.8) | 1.000 |
Alcoholism | 5 (10.2) | 1 ( 2.3) | 0.207 |
Autoimmune disease | 3 ( 6.1) | 1 ( 2.3) | 0.619 |
No underlying diseases | 3 ( 6.1) | 5 (11.4) | 0.470 |
APACHE II score > 25 | 35 (71.4) | 13 (29.5) | <0.001 |
Days of hospitalization | 28 ± 24 | 21 ± 15 | 0.929 |
Initial presentation with septic shock | 25 (51) | 14 (31.8) | 0.061 |
Initial presentation with respiratory failure | 30 (61.2) | 14 (31.8) | 0.005 |
PSI Risk Class V | 44 (89.8) | 27 (61.4) | 0.001 |
ICU admission | 28 (57.1) | 14 (31.8) | 0.014 |
Concurrent lung abscess | 3 ( 6.1) | 0 ( 0) | 0.244 |
Early mortality (deaths ≦ 48 hrs) | 18 (36.7) | 6 (13.6) | 0.011 |
In-hospital mortality | 27 (55.1) | 12 (27.3) | 0.007 |
Laboratory findings for bacteremic community-acquired pneumonia due to K. pneumoniae
Characteristic |
K. pneumoniae
(n = 49) No. (%) |
S. pneumoniae
(n = 44) No. (%) |
p-value |
---|---|---|---|
Chest radiography at admission | |||
Unilateral involvement | 17 (34.7) | 34 (77.3) | <0.001 |
Bilateral involvement | 32 (65.3) | 10 (22.7) | <0.001 |
Cavity lesion | 3 (6.1) | 1 (2.3) | 0.619 |
Initial laboratory value | |||
Leucocyte count, × 103/μL | 11.6 ± 6.7 | 14.4 ± 7.4 | 0.044 |
Platelet, × 103/μL | 212 ± 101 | 196 ± 107 | 0.969 |
Albumin, g/dL | 2.6 ± 0.6 | 2.8 ± 0.6 | 0.072 |
C-reactive protein, mg/dL | 21.8 ± 11.2 | 24.9 ± 1.5 | 0.664 |
Serum creatinine, mg/dL | 2.3 ± 1.9 | 2.3 ± 1.4 | 0.186 |
Total biliburin, mg/dL | 1.2 ± 2.7 | 1.1 ± 1.3 | 0.809 |
Glucose, mg/dL | 220 ± 168 | 208 ± 202 | 0.528 |
Factors associated with mortality in K. pneumoniae bacteremic CAP
Characteristic | Survivors (n = 22) No. (%) | Non-survivors (n = 27) No. (%) |
p-value |
---|---|---|---|
Age > 65 years | 15 (68.2) | 22 (81.5) | 0.282 |
Male | 19 (86.4) | 20 (74.1) | 0.288 |
Initial presentation with septic shock | 4 (18.2) | 21 (77.8) | <0.001 |
Initial presentation with respiratory failure | 7 (31.8) | 23 (85.2) | <0.001 |
APACHE II score>25 | 10 (45.5) | 25 (92.6) | <0.001 |
PSI Risk Class V | 18 (81.8) | 26 (96.3) | 0.160 |
ICU admission | 10 (45.5) | 18 (66.7) | 0.136 |
Malignancy | 5 (22.7) | 9 (33.3) | 0.414 |
Diabetes mellitus | 10 (45.5) | 7 (25.9) | 0.153 |
Liver cirrhosis | 1 ( 4.5) | 3 (11.1) | 0.617 |
Chronic kidney disease stage≧4 | 6 (27.3) | 7 (25.9) | 0.915 |
Chronic lung diseases | 12 (54.5) | 11 (40.7) | 0.336 |
Neurologic disorders | 7 (31.8) | 5 (18.5) | 0.282 |
Autoimmune disease | 1 ( 4.5) | 1 ( 3.8) | 1.000 |
Alcoholism | 2 ( 9.1) | 3 (11.1) | 1.000 |
No underlying diseases | 1 ( 4.0) | 2 ( 7.4) | 0.609 |
Chest radiography--bilateral involment | 14 (63.6) | 18 (66.7) | 0.825 |
Leucopenia a
| 2 (9.1) | 4 (14.8) | 0.678 |
Thrombocytopenia | 2 (9.1) | 9 (33.3) | 0.043 |
C-reactive protein, mg/dL | 20.9 ± 12.1 | 22.7 ± 10.6 | 0.482 |
Susceptibility testing
Capsular serotypes and virulence factors of K. pneumoniae
Characteristic | Serotype K1, n = 7 No. (%) | Serotype K2, n = 19 No. (%) | Serotype non-K1/K2, n = 23 No. (%) |
p-valuea
|
---|---|---|---|---|
Age > 65 years | 5 (71.4) | 14 (73.7) | 18 (78.3) | 0.674 |
Male sex | 4 (57.1) | 15 (78.9) | 20 (87) | 0.229 |
Underlying disease or risk factor | ||||
Malignancy | 1 (14.3) | 5 (26.3) | 8 (34.8) | 0.365 |
Diabetes mellitus | 5 (71.4) | 6 (31.6) | 6 (26.1) | 0.234 |
Liver cirrhosis | 0 (0) | 2 (10.5) | 2 (8.7) | 1.000 |
Chronic kidney disease stage≧4 | 1 (14.3) | 5 (26.3) | 7 (30.4) | 0.560 |
Chronic lung diseases | 2 (28.6) | 10 (52.6) | 11 (47.8) | 0.907 |
Neurologic disorders | 3 (42.9) | 2 (10.5) | 7 (30.4) | 0.363 |
Autoimmune disease | 0 (0) | 2 (10.5) | 1 (4.3) | 1.000 |
Alcoholism | 1 (14.3) | 2 (10.5) | 2 (8.7) | 1.000 |
CXR--bilateral involvement | 6 (85.7) | 12 (63.2) | 14 (60.9) | 0.539 |
Leucopenia b
| 1 (14.3) | 3 (15.8) | 2 (8.7) | 0.671 |
Concurrent lung abscess | 0 (0) | 2 (10.5) | 1 (4.3) | 1.000 |
Initial presentation with septic shock | 4 (57.1) | 10 (52.6) | 11 (47.8) | 0.674 |
Initial presentation with respiratory failure | 4 (57.1) | 12 (63.2) | 14 (60.9) | 0.962 |
APACHE-II score>25 | 5 (71.4) | 15 (78.9) | 15 (65.2) | 0.365 |
PSI Risk Class V | 7 (100) | 17 (89.5) | 20 (87) | 0.655 |
ICU admission | 3 (42.9) | 12 (63.2) | 13 (56.5) | 0.934 |
Early deaths ≦ 48 hrs | 3 (42.9) | 7 (36.8) | 8 (34.8) | 0.790 |
In-hospital death | 4 (57.1) | 11 (57.9) | 12 (52.2) | 0.698 |