[Diffuse astrocytoma presenting as an optic-spinal syndrome]

Spinal cord involvement is a rare presentation of grade II astrocytomas. Nevertheless, differentiation from inflammatory demyelinating diseases of the central nervous system can be challenging in some clinical situations. A patient with an optic-spinal syndrome due to a fibrillary astrocytoma is described.

A 32 years-old man was admitted to the hospital because of a subacute spinal cord syndrome. Brain MRI showed no abnormalities, and spinal MRI disclosed a cervical cord lesion suggestive of myelitis. Cerebrospinal fluid analysis revealed oligoclonal bands. Clinical improvement was observed after corticosteroid treatment. Three months later, the patient presented with binocular vision loss. A bilateral retrobulbar optic neuritis was suspected, and corticosteroid therapy was administered again. A new MRI with spectroscopy revealed an infiltrative lesion involving the right frontal lobe, optic chiasm, internal capsule, brainstem and cervical spinal cord, which was suggestive of low-grade astrocytoma. Brain biopsy confirmed the diagnosis of diffuse fibrillary astrocytoma.

Differential diagnosis between inflammatory and neoplastic lesions of the central nervous system requires close clinical-radiological follow-up. In this clinical situation, treatment response to corticosteroids and presence of oligoclonal bands in the cerebrospinal fluid may be not necessarily indicative of an inflammatory demyelinating process. Brain biopsy is often necessary for a definite diagnosis.