Association of amyotrophic lateral sclerosis and Behcet's disease: is there a relationship? A multi-national case series.

Neurological involvement may be seen in 5-30% of the patients with Behcet's disease (BD). Occasionally, parenchymal neurological involvement in BD can present as a spinal cord syndrome. However, motor neuron disease-like presentation is extremely uncommon. Here we are reporting five patients (all male; median age, 38) fulfilling both International Study Group criteria for BD and El Escorial criteria for amyotrophic lateral sclerosis (ALS). These patients were identified by a questionnaire sent to the members of the Neuro-Behcet Study Group of the International Study Group for BD. Three out of five patients had only motor presentations. In two patients, sensory and urinary manifestations were present as well. Spinal cord MRIs were normal in all, and brain MRIs were normal in four patients; one patient had nonspecific white matter changes. Two patients passed away 1-3 years after diagnosis of ALS, and two patients were lost to follow-up 3 and 11 years after admission; one patient is still alive 3 years after onset. The patients that are presented here might represent a rare form of neurological involvement in BD as well as sole coincidence. Larger prospective series are needed to further answer this issue.