Evaluation of the use of the bioMerieux Rapid ID32 A for the identification of Clostridium botulinum.

The neurotoxins produced by Clostridium botulinum are amongst the most potent known to man. Toxin production is detected by a mouse bioassay, which requires several days for a result and is not acceptable for routine use unless there is a high level of suspicion. The Rapid ID32 A kit produced by bioMerieux gives an identification of an isolate within 4 h. The aim of this study was to examine the efficiency of the identification of Cl. botulinum using the Rapid ID32 A. Forty-two strains of Cl. botulinum, one strain each of botulinum toxin-producing Cl. butyricum and Cl. baratii, and four strains of Cl. sporogenes, were tested. One strain of Group I Cl. botulinum gave a presumptive identification of Group II Cl. botulinum, six strains of Cl. botulinum were identified as 50-98% Cl. botulinum in some tests, and 17 strains of Cl. botulinum were identified as < 50% Cl. botulinum. Thirteen strains of Cl. botulinum were identified as > 99% Cl. sporogenes or 86% Cl. histolyticum, and five strains gave a combination of these results. All strains of Cl. sporogenes were correctly identified. These results show that some strains of Cl. botulinum may not be correctly identified using the Rapid ID32A.