Table 3. Number and percentage of antimicrobial resistant Shigella strains.
| Microorganism | serotype* | N | Amp |
Sxt |
Tet |
Chl |
Azm1 |
|||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| n | % | n | % | n | % | n | % | n | % | |||
| S. flexneri | 55 | 40 | 73 | 47 | 85 | 42 | 76 | 39 | 71 | 1 | 2 | |
| 2a | 28 | 25 | 89 | 26a | 93 | 27a | 96 | 24c | 86 | 1 | 4 | |
| 4a | 6 | 0 | -- | 6 | 100 | 0 | -- | 0 | -- | 0 | -- | |
| Other | 21 | 15 | 71 | 15 | 71 | 15b | 71 | 15a | 71 | 0 | -- | |
|
| ||||||||||||
| S. boydii | 12 | 3 | 25 | 9 | 75 | 6 a | 50 | 2 | 17 | 0 | -- | |
|
| ||||||||||||
| S. sonnei | 12 | 12 | 100 | 12 | 100 | 12 | 100 | 12 | 100 | 4 | 33 | |
| I** | 7 | 7 | 100 | 7 | 100 | 7 | 100 | 7 | 100 | 1 | 14 | |
| II | 5 | 5 | 100 | 5 | 100 | 5 | 100 | 5 | 100 | 3 | 60 | |
|
| ||||||||||||
| S. dysenteriae | 4 | 1 | 25 | 3 | 75 | 1 | 25 | 1 | 25 | 1 | 25 | |
|
| ||||||||||||
| Total | 83 | 56 | 67 | 71 | 86 | 61 | 74 | 54 | 65 | 6 | 7 | |
1
: Isolates which posses a azithromycin halo less than 15 mm, In all cases the MIC ranges between 4 and 8 μg/ml.
*
Only those with at minimum of 5 isolates;
**
In the case of S. sonnei, refers to phase
a
: 1 intermediate isolate,
b
: 2 intermediate isolates,
c
: 6 intermediate isolates
Amp: Ampicillin, Sxt: trimethoprim-sulfamethoxazole; Tet: Tetracycline; Chl: Chloramphenicol; Azm: Azithromycin
No resistance to nalidixic acid, ciprofloxacin or ceftriaxone was found, and only 1 intermediate isolate to nitrofurantoin was detected.