Background
Methods
Ethics statement
Study setting and patient population
Blood culturing and bacterial identification
Antimicrobial susceptibility testing
Genotypic screening of ESBL and AmpC genes
Statistical analysis
Results
Gram-negative organisms with reduced susceptibility against third generation cephalosporins isolated from bloodstream infections at the Hospital for Tropical Diseases
Resistance phenotype | ||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Species | CAI (n = 876) | HAI (n = 141) | Total (n = 1017) | amk | amc | caz | cip | cro | etp | fep | imp | mem | ofx | sxt | tcc | tzp |
Enterobacteriaceae (n = 783) | ||||||||||||||||
Edwardsiella spp. | 2 | 0 | 2 (0.2%) | – | – | – | – | – | – | – | – | – | 1 | 1 | – | – |
Enterobacter spp. | 9 | 4 | 13 (1.3%) | – | 8 | 8 | 1 | 10 | – | 1 | – | – | 1 | 4 | 5 | 1 |
E. coli
|
392
|
53
|
445 (43.8%)
| 2 | 80 | 201 | 196 | 203 | 5 | 179 | 1 | 1 | 200 | 298 | 262 | 24 |
Klebsiella
spp.
|
127
|
27
|
154 (15.1%)
| 1 | 15 | 23 | 19 | 24 | 3 | 18 | 2 | 3 | 19 | 51 | 30 | 8 |
Morganella morganii
| 2 | 1 | 3 (0.3%) | – | 3 | 2 | – | 3 | – | – | 1 | – | – | 1 | – | – |
Proteus mirabilis
| 2 | 6 | 8 (0.8%) | – | – | 1 | 3 | 1 | – | 1 | – | – | 3 | 5 | 1 | – |
Providencia spp. | 1 | 1 | 2 (0.2%) | – | 1 | – | – | – | – | – | – | – | – | – | – | – |
Non-typhoidal
Salmonella
| 102 | 9 |
111 (10.9%)
| – | – | 1 | 3 | 1 | – | 1 | – | – | 3 | 29 | 28 | – |
Salmonella Typhi | 40 | 4 | 44 (4.3%) | – | – | – | – | – | – | – | – | – | – | 11 | – | – |
Serratia marcescens
| 0 | 1 | 1 (0.1%) | – | 1 | – | – | 1 | – | – | – | – | – | – | – | – |
Non-Enterobacteriaceae (n = 234) | ||||||||||||||||
Aeromonas
spp.
|
51
|
8
|
59 (5.8%)
| – | 24 | 23 | – | 27 | – | – | – | – | 1 | 9 | 20 | – |
Abiotrophia spp. | 1 | 0 | 1 (0.1%) | – | – | – | – | – | – | – | – | – | – | 1 | – | – |
Archromobacter xylosoxidans
| 1 | 1 | 2 (0.2%) | 1 | – | 1 | 1 | 2 | – | 1 | – | – | – | 1 | 1 | – |
Alcaligenes spp. | 8 | 3 | 11 (1.1%) | 4 | 2 | 1 | 1 | 3 | – | 4 | – | – | 1 | 1 | 1 | – |
Brevundimonas vesicularis
| 2 | 0 | 2 (0.2%) | No information available | ||||||||||||
Burkhoderia cepacia
|
28
|
8
|
36 (3.5%)
| – | – | 1 | – | – | – | – | – | – | 1 | – | – | |
Burkhoderia pseudomallei
|
51
|
0
|
51 (5.0%)
| – | – | – | – | – | – | – | – | – | – | – | – | – |
Campylobacter spp. | 13 | 0 | 13 (1.3%) | – | – | – | 8 | – | – | – | – | – | 10 | – | – | – |
Chryseomonas spp. | 2 | 2 | 4 (0.4%) | 3 | 2 | 1 | 2 | 2 | – | 2 | 3 | 3 | 2 | 2 | 2 | 1 |
Comamonas spp. | 1 | 1 | 2 (0.2%) | No information available | ||||||||||||
Gemella spp. | 1 | 0 | 1 (0.1%) | No information available | ||||||||||||
Haemophilus spp. | 9 | 2 | 11 (1.1%) | – | 1 | – | 5 | 1 | – | – | – | – | – | 8 | – | – |
Moraxella spp. | 1 | 1 | 2 (0.2%) | – | – | – | – | – | – | – | – | – | – | – | – | – |
Neisseria meningitidis
| 5 | 0 | 5 (0.5%) | – | – | – | – | – | – | – | – | – | – | – | – | – |
Pasteurella spp. | 6 | 0 | 6 (0.6%) | 1 | – | – | – | 1 | – | 1 | – | – | – | – | – | – |
Psychrobacter spp. | 2 | 0 | 2 (0.2%) | No information available | ||||||||||||
Ralstonia pickettii
| 4 | 2 | 6 (0.6%) | 4 | 1 | 1 | – | – | – | 2 | 1 | 2 | – | 1 | 3 | 1 |
Roseomonas spp. | 2 | 0 | 2 (0.2%) | 1 | – | – | – | – | – | – | – | – | – | – | – | – |
Sphingomonas spp. | 2 | 1 | 3 (0.3%) | – | 1 | 2 | – | – | – | 2 | – | – | – | – | – | 1 |
Stenotrophomonas maltophilia
| 6 | 5 | 11 (1.1%) | – | – | 7 | – | – | – | – | – | – | – | 2 | 6 | – |
Vibrio spp. | 3 | 1 | 4 (0.4%) | – | – | – | – | – | – | – | – | – | – | 1 | – | – |
Molecular analysis of ESBL and AmpC genes conferring resistance to third generation cephalosporins
Gene |
E. coli
|
Klebsiella spp.
|
Enterobacter cloacae
|
Salmonella cholerasuis
| Totala
|
---|---|---|---|---|---|
bla
CTX-M
| 157 | 9 | 1 | 1 | 168 (95%) |
bla
TEM
| 70 | 7 | 1 | 1 | 79 (45%) |
bla
OXA
| 33 | 2 | 1 | – | 36 (20%) |
bla
SHV
| 1 | 4 | – | – | 5 (3%) |
Not detected | 3 | 1 | – | – | 4 (2%) |
Gene |
Aeromonas spp.
|
E. coli
|
Klebsiella spp.
|
Enterobacter spp.
|
M. morganii
| Totala
|
---|---|---|---|---|---|---|
bla
CIT
| – | 18 | – | 1 | – | 19 (28%) |
Bla
DHA
| – | 1 | 6 | – | 2 | 9 (13%) |
Bla
EBC
| – | – | – | 3 | – | 3 (4%) |
Not detected | 25 | 5 | 2 | 5 | – | 37 (54%) |
Gene |
Aeromonas spp. |
E. coli
|
Klebsiella spp. |
Enterobacter spp. |
M. morganii
| Totala
|
---|---|---|---|---|---|---|
bla
CTX-M
| 3 | 3 (4%) | ||||
bla
TEM
| – | 15 | – | 1 | 1 | 17 (25%) |
bla
SHV
| – | – | 4 | 1 | – | 5 (7%) |
bla
OXA
| – | 2 | – | – | – | 2 (3%) |
bla
OXA & bla
TEM
| – | 1 | 1 | – | – | 2 (3%) |
bla
OXA, bla
TEM
& bla
CTX-M
| – | 1 | 1 | 1 | – | 3 (4%) |
Not detectedb
| 25 | 2 | 2 | 6 | 1 | 36 (53%) |