Acute infantile motor unit disorder. Infantile botulism?

Eight infants with an acute reversible motor unit disorder are described, including two infants from whom Clostridum botulinum type A was isolated from stool specimens. The clinical spectrum includes constipation, cranial nerve deficits, pupillary involvement, and generalized hypotonic weakness. There were no deaths, and all infants have had complete clinical recovery. A characteristic electromyographic (EMG) pattern was present in part until clinical recovery. This distinctive pattern consisted of brief, small, abundant for power exerted motor unit potentials. This EMG pattern in the context of the clinical syndrome may well be diagnostic for acute infantile motor unit disorder.