[Failure of empirical treatment with ceftriaxone in motor neuron disease].

We describe two patients with lateral amyotrophic sclerosis who, after informed consent, received empirical treatment with intravenous cephtriaxone at a dose of 2 g/24 hours for three weeks, with no positive results. The pharmacokinetics of this cephalosporin is analyzed, along with the relationship between motor neuron disease, neuroborreliosis and immunoreactivity to Borrelia burgdorferi.