Devic’s neuromyelitis optica (NMO) is a severe demyelinating disease of the CNS, often misdiagnosed as multiple sclerosis, and involving mainly optic nerves and the spinal cord. According to recent criteria,1 other CNS parts may also be involved, notably the periventricular white matter and the hypothalamus.2

NMO pathophysiology remains obscure—necrotic-haemorrhagic lesions coexisting with inflammatory lesions. An important breakthrough came from the recent discovery of highly specific antibodies linked to a water aquaporin channel,3 which is most abundant in the astrocytes of the blood–brain barrier.

We report on a peculiar case of relapsing NMO with severe recurrent dysautonomia and hypersomnia, in which we had the opportunity to observe a dramatic decrease in hypocretin/orexin cerebrospinal fluid (CSF) level.

CASE REPORT

A Caucasian woman born in 1953 was first seen in 1999 for an episode of sensorimotor deficit in the right upper and lower limbs; MRI disclosed a cervical lesion from C3 to C7 and inflammatory myelopathy was the provisional diagnosis. Recovery was complete after five methylprednisolone infusions. In April 2001, she presented with complete paralysis of the left lower limb; MRI of the spine disclosed an enlarged, non-enhancing lesion from C4 to T9. No CSF …