Rare onset symptoms in multiple sclerosis.

Introduction: Multiple sclerosis (MS) may present with unusual manifestations such as pain syndromes, movement disorders, rare cranial nerve involvement, cognitive or psychiatric symptoms, leading to diagnostic dilemma. The purpose of this study is to determine the types of rare onset symptoms in patients with MS in order to provide better clues for early diagnosis.

Method: We, retrospectively, analysed data of 680 MS patients who were diagnosed or followed-up in our demyelinating diseases unit. Onset symptoms such as visual field defects, rare cranial nerve involvement, paroxysmal symptoms, movement disorders, pain syndromes, cognitive and psychiatric manifestations were recorded.

Results: Nineteen MS patients (13 women) were identified as having unusual initial manifestations. None of these cases had typical optic, brainstem, sensory, motor or cerebellar signs. Five patients presented with rare cranial nerve involvement, five patients with pain syndromes, four patients with movement disorders, two patients with paroxysmal symptoms, two patients with cognitive deficits and one patient with homonymous hemianopia. None of these patients were diagnosed with MS at initial presentation; all of them were diagnosed with MS in the following months or years.

Conclusion: This retrospective study indicates that there is a wide range of rare initial manifestations of MS due to diverse involvement of central nervous system. Rare, unusual symptoms complicate early diagnosis. Given the fact that disease modifying treatment should be initiated early, it is crucial to diagnose MS as early as possible. Therefore, physicians should not disregard MS when a patient presents with any of these rare manifestations.