Table 1 Mean annular radius and expected ranges of WHO Neisseria gonorrhoeae reference strains (F, G, K, L, M, N, O and P)
Methods | Antibiotics tested | F | G | K | L | M | N | O | P | |
|---|---|---|---|---|---|---|---|---|---|---|
CDS | Penicillin G | Mean annular radius (range) | 13.2 (12–15) | 5.5 (3–7) | 00 | 00 | 00 | 00 | 00 | 6 (5–7) |
Expected result | >9 (S) | 3–9 (I) | <3 (R) | <3 (R) | <3 (R) | <3 (R) | <3 (R) | 3–9 (I) | ||
β-lactamase production | No | No | No | No | Yes | Yes | Yes | No | ||
Expected result | No | No | No | No | Yes | Yes | Yes | No | ||
Ciprofloxacin | Mean annular radius (range) | 15 (14–17) | 7.7 (7–9) | 00 | 00 | 3.2 (02–4) | 00 | 13.5 (12–15) | 14.2 (13–16) | |
Expected result | ≥11 (S) | 6–10 (I) | <6 (R) | <6 (R) | <6 (R) | <6 (R) | ≥11 (S) | ≥11 (S) | ||
Spectinomycin | Mean annular radius (range) | 11 (10–11) | 10.2 (9–11) | 16 (15–18) | 9.5 (8–11) | 11 (9–13) | 13.5 (10–17) | 00 | 13 (11–15) | |
Expected result | ≥6 (S) | ≥6 (S) | ≥6 (S) | ≥6 (S) | ≥6 (S) | ≥6 (S) | <6 (R) | ≥6 (S) | ||
Azithromycin | Mean annular radius (range) | 12.5 (10–15) | 14 (12–16) | 13.5 (12–15) | 11 (9–13) | 12 (9–15) | 11.5 (10–13) | 13 (12–15) | 1.5 (0–4) | |
Expected result | ≥8 (S) | ≥8 (S) | ≥8 (S) | ≥8 (S) | ≥8 (S) | ≥8 (S) | ≥8 (S) | <8 (R) | ||
Ceftriaxone | Mean annular radius (range) | 14.2 (12–16) | 14.7 (14–16) | 6.7 (6–8) | 5.5 (5–7) | 13 (12–15) | 13.2 (12–15) | 13.2 (13–15) | 13.7 (13–15) | |
Expected result | ≥10 (S) | ≥10 (S) | 5–9 (DS) | 5–9 (DS) | ≥10 (S) | ≥10 (S) | ≥10 (S) | ≥10 (S) | ||
MIC by Etest | Ceftriaxonea | Etest MIC ranges | <0.002 | 0.004–0.008 | 0.064–0.125 | 0.125–0.25 | 0.008–0.016 | 0.002–0.004 | 0.016–0.032 | 0.004–0.008 |
Expected result | <0.002 (S) | 0.004–0.016 (S) | 0.032–0.125 (DS) | 0.064–0.25 (DS) | 0.008–0.032 (S) | 0.002–0.008 (S) | 0.016–0.064 (S) | 0.002–0.008 (S) | ||