Paroxysmal Kinesogenic Dyskinesia As a Presenting Symptom of Neuromyelitis Optica

Background: PKDs, sudden attack of involuntary movements, are rare movement disorders. Secondary PKDs have been reported in conditions such as multiple sclerosis but only a few cases have been described in NMO.

Objectives: To report 2 cases of paroxysmal kinesogenic dyskinesia (PKD) as the presenting symptom in Neuromyelitis Optica (NMO)

Methods and Results:

Case 1: A 47-year-old man with a remote history of optic neuritis presented with 3-month of painful episodic involuntary choreoathetoid movements of his right upper extremity, triggered by movement, and weakness and paresthesias of his right lower extremity. NMO antibody was positive.  MRI C-spine showed T2 signal intensity involving C3-C6. He was started on mycophenolate mofetil but later received plasmapheresis and rituximab with moderate response. Carbamazepine was started for PKD but discontinued due to rash. Phenytoin alone or in combination with baclofen was tried with no benefit. His PKD improved with a combination of valium, gabapentin and baclofen.

Case 2: A 45-year-old woman presented in 2009 with 2-weeks of weakness on the right upper and lower extremities, painful involuntary flexion of right fingers and forearm, and dystonic extensor posturing of the left upper extremity. MRI C-spine revealed T2 hyperintensity involving C2-T1. She was treated with cyclophosphamide induction therapy and maintained on methotrexate. In 2013, she relapsed and was found to have aquaporin 4 antibodies. She received IVIG and rituximab without benefit and was retreated with cyclophosphamide with good results.  PKD was treated with clonazepam, tegretol, gabapentin and baclofen with adequate control.

Conclusions: PKDs are rare neurological disorders. Even though most cases are idiopathic; secondary PKDs due to multiple sclerosis have been described. PKDs are rarely associated with NMO; and in the few cases we reviewed, all responded to a single anticonvulsant treatment. Here, we report 2 rare cases of PKD as presenting symptom of NMO requiring multiple medications to achieve relief.