Histological examination of the central nervous system in the diagnosis of botulism.

Type C botulinum toxin was given to mice by mouth or intraperitoneal injection. The central nervous system (CNS) of control and affected mice was examined by histological methods such as would be used in a field investigation of botulism. The only change definitely associated with intoxication was microscopic haemorrhage and vascular engorgement; other changes were considered incidental or artefactual. The results are discussed in the light of other descriptions of botulism in animals. It is concluded that non-specific petechiation and vascular engorgement sometimes occur in the CNS in botulism but that the only way routine histology may support a diagnosis of botulism is by exclusion of other diseases.