[Neuromyotonic syndrome]

A syndrome with constant rest activity was observed in the EMG of a 28-years-old female patient. An H-reflex was detected for normal nerve conduction velocity. Hypomagnesemia was striking among the laboratory values. Bioptic investigation yielded centralisation of nuclei, variations in the diameter of muscle fibres and a predominance of type I fibres. The findings and the response to Finlepsin point to neuromyotonic syndrome.