Performance characteristics of N gonorrhoeae culturing at five laboratories in St Petersburg and Leningradskaya Oblast, Russia in 2004
| Lab* | Culture medium | Quality control of the medium growth (sterility) | Incubation time | Species confirmation | Antibiotic susceptibilitytesting† | |||||
|---|---|---|---|---|---|---|---|---|---|---|
| *All the laboratories performed bedside microscopy and culturing. | ||||||||||
| †Disc diffusion method was utilised on Complegon. The discs were purchased from Research Centrum for Pharmacotherapy (St Petersburg, Russia) or HiMedia Laboratories Limited (Mumbai, India). The utilised interpretative criteria—that is, zone diameter break points, were from HiMedia Laboratories Limited and had been determined on a Mueller Hinton agar based medium. | ||||||||||
| ‡Slides (5.0×1.5 cm) with a thin layer (1–2 mm) of selective culture medium—that is, modified Thayer-Martin medium, which are incubated in accompanying tubes with sterile water in the bottom and carbon dioxide (CO2) generating tablets at 36–38°C. Biocult-GC and accessories, including oxidase reagent, are manufactured by Orion Diagnostica, Espoo, Finland. | ||||||||||
| §API NH (bioMérieux, Lyon, France) for biochemical species confirmation. | ||||||||||
| ¶AmpliSens Neisseria gonorrhoeae PCR kit (Interlabservice, Moscow, Russia), which is a Russian PCR assay that separately targets both the cppB gene and the cytosine DNA methyltransferase gene. | ||||||||||
| **Non-selective Russian culture medium manufactured by St Petersburg Institute of Vaccines and Sera, Russia, which contains agar, rabbit meat extract, Bacto-pepton, NaCl, autolysate of yeasts, orotic acid (6-carboxyuracil), bovine serum, and hydrolysate of casein. The inoculated medium was incubated in candle jars with a small volume of water in the bottom at 36–38°C. | ||||||||||
| ††Neisseria 4H (Bio-Rad, Marnes-la-Coquette, France) for biochemical species confirmation. | ||||||||||
| A | Biocult-GC‡ | Every new batch, N gonorrhoeae reference strains are cultured (36–38°C, 48 hours) | 48 hours | Oxidase test, Microscopy (Gram staining, 1000× magnification), API-NH§, PCR¶ | – | |||||
| B | Complegon** (60 mm plates, 10–12 ml per plate) or Biocult-GC‡ (for extragenital specimens) | If recognised problem, N gonorrhoeae clinical isolate is cultured (36–38°C, 48 hours) | 48 hours (examined also after 24 hours) | Oxidase test, Microscopy (Gram, 900×), Neisseria-4H†† | Rarely | |||||
| C | Complegon** (40 mm plates, 5 ml per plate) | Every new batch, N gonorrhoeae clinical isolate is cultured (36–38°C, 48 hours) | 48 hours (examined also after 24 hours) | Oxidase test, Microscopy (Gram and 1000×) | – | |||||
| D | Complegon** (3–3.5 ml slanted in glass tubes or, for children, 60 mm plates, 10–15 ml per plate) | If recognised problem, N gonorrhoeae clinical isolate is cultured (37°C, 24 hours) | 24 hours | Oxidase test, Microscopy (Gram and 1000×) | Rarely | |||||
| E | Complegon** (3–3.5 ml slanted in glass tubes) | − (37°C, 24 hours) | 72 hours (examined also after 24 and 48 hours) | Oxidase test, Microscopy (Gram and 1000×) | – | |||||