[Alert patients with mydriasis and fixed pupils].

Mydriasis is a rare phenomenon in non-comatose patients, usually caused by toxic agents or oculomotor neuropathy. We describe two patients who presented with mydriasis at the outpatient clinic. The first patient was a 46-year-old woman with mydriasis, headache, ptosis, ophthalmoplegia and transient ataxia after an influenza vaccination. The second was a 47-year-old woman with mydriasis, ophthalmoplegia, ptosis and ataxia after she had used doxycycline for an upper respiratory tract infection. In both patients, GQ1b-antibodies were detected and both were diagnosed with Miller Fisher syndrome. The second patient was treated with immunoglobulins, the other patient improved spontaneously. Miller Fisher syndrome is characterised by a triad of ophthalmoplegia, ataxia and areflexia. An infection or vaccination may give rise to an auto-immune response with GQ1b-antibodies directed against gangliosides in peripheral nerve tissue. The Miller Fisher syndrome has a good prognosis with spontaneous recovery ensuing in most patients. Treatment with immunoglobulins is required in some patients.