A 38 year old man presents with generalized weakness and an unsteady gait for 1 day, in a background of anorexia, nausea and vomiting for 2 days. There was no history of fever, headache, or trauma. Five days ago, he returned from a visit to Queensland, Australia, where he went hiking in the bush for several days. His medical history is unremarkable. He is not on any drugs and denies substance abuse.
Compound muscle action potentials are diminished in both radial and ulnar nerves. Nerve conduction velocities are within normal limits, with a normal response to repetitive stimulation.
The CSF analysis is within normal parameters.
The MRI scan of the spine appears completely normal.
A botulinum toxin screen of stools and serum is performed; results will be available in 2 days. Stool cultures for C. botulinum are obtained; results will be available in 2 weeks.