Table 1.

Comparison of systems and schemes for the identification of gram-positive bacteria

Characteristic and test typeIdentification systema
IdentifiesMicrococcaceae andStreptococcaceaeIdentifiesMicrococcaceaeIdentifies Streptococcaceae
MS GPMS Rapid GPVitek GPIPasco GP IDAPI Staph IDGeary et al. (86)Kloos and Bannerman (129)API Staph ID 32StaphZymRapID STRRapid ID 32 StrepAPI 20 Strep
Characteristics
 Inoculum density (McFarland)0.50.50.5–10.530.52144
 Inoculum vol (ml)36.51.8322–3312–32
 No. of tests included263429181015362610143220
 No. of additional tests213211014232
 No. of reagents5003101163155
 No. of taxa included4850442617123632265248
 Storage temp (°C)b RT2–82–82–82–82–82–82–8
 Medium for inoculum sourceb TSA + 5% SBTSA + 5% SBBHIVSBA
 Incubation period (h)16–4224–1516–20518–2418–722418–24444–24
Test type (no. of tests)
 Glycosidases/phosphatases4120341434484
 Formation of acid10111864101214241710
 Peptidases1100100221432
 Hydrolases101102510112
 Other metabolic tests412321753132
 Growth and tolerance tests60840161000
 Mandatory additional testsc C, HCC, Cg, HC, HCCCGC, HC, H, PC, H
  • a MS GP, MicroScan Conventional Gram-Positive Panel; MS Rapid GP, MicroScan Rapid Gram-Positive Panel; Vitek GPI, Vitek Gram Positive Identification Card; Pasco GP ID, Pasco Gram-Positive ID; API Staph ID, API STAPH IDENT; Geary et al. (86), based on multipoint inoculation of agar plates.

  • b RT, room temperature; TSA + 5% SB, Trypticase soy agar plus 5% sheep blood; BHI, brain heart infusion broth; V, various media; SBA, sheep blood agar.

  • c C, catalase; Cg, coagulase; H, hemolysis; G, growth and tolerance tests that need to be done separately from the kit; P, pigmentation.