Neuro-Behcet Disease

General Information

  • Excluding headaches, neurological complications of Behçet syndrome (neuro-Behçet syndrome) occur in less than 12% of cases, often a few years after the onset of the other systemic features.

Clinical Manifestations and Diagnosis

  • In parenchymal disease, meningoencephalitis occurs, with a mixed inflammatory cell infiltrate leading to necrosis and apoptotic neuronal loss. Inflammatory infiltration, rather than fibrinoid necrosis, is seen around small vessels.
    • The brainstem and mid-brain are the most commonly affected areas, but spinal cord lesions and cerebral involvement may also occur and, occasionally, neuro-Behçet syndrome presents as a pseudotumour cerebri.
    • Brainstem involvement usually presents subacutely, with headache, cranial neuropathies or cerebellar or corticospinal tract dysfunction.
    • Sensorineural hearing loss can occur, resulting in sudden deafness, balance disturbances and dizziness.
    • The characteristic MRI lesion in parenchymal neuro-Behçet syndrome is a unilateral upper brainstem lesion extending into the thalamus and basal ganglia.
    • Analysis of cerebrospinal fluid shows a neutrophilic (in early disease) or lymphocytic (in late disease) pleocytosis, but usually no oligoclonal bands.
  • Neurovascular disease accounts for approximately 20% of cases of neuro-Behçet syndrome and symptoms include dural sinus thrombosis, intracranial aneurysm and extracranial aneurysm and/or dissection.
    • The clinical findings are usually limited to those of intracranial hypertension (that is, headache, vomiting, altered levels of consciousness and papilloedema).
    • Intracranial hypertension may be present without MRI abnormalities and should be managed in the same way as idiopathic benign intracranial hypertension.
    • Aneurysms of the cerebral, vertebral and carotid arteries can also occur.

Management

  • Headaches are often under-treated. An effort should be made to classify the type of headache and, in the case of migraine, agents such as pizotifen and β­blockers should be offered.
  • Parenchymal disease:
    • Initial Management: treated with high-dose steroids in the first instance, along with initiation of a DMARD, usually azathioprine.
      • Methotrexate, mycophenolate, cyclophosphamide, tacrolimus and IFN-­α are probably effective, although evidence is lacking.
      • Cyclosporin is potentially neurotoxic and should not be used for patients with a history of CNS disease.
    • The alternative therapeutic option for severe and aggressive disease is the early use of a biologic agent (i.e. anti-TNF therapy, like infliximab)
  • Neurovascular disease:
    • Cerebral vascular thrombosis and aneurysms also require aggressive immunosuppression.
    • Anti-coagulation for venous thrombosis needs to be assessed on a case-by-case basis.

Ambrose, N. L. & Haskard, D. O. Nat. Rev. Rheumatol. 9, 79–89 (2013); published online 25 September 2012; doi:10.1038/nrrheum.2012.156