Case Presentation: A 60-year-old female with metastatic breast cancer presented with involuntary irregular forceful and painful contractions of facial muscles and dystonic posturing of her hands and feet lasting 5 to 30 minutes. Episodes sporadically occurred up to 20 times daily. MRI brain and spinal cord showed no evidence of metastatic disease or dural enhancement. EEG was negative for seizure activity. CSF cytology was negative for malignant cells but protein count and IgG were elevated suggesting an inflammatory process. Paraneoplastic autoantibody was negative but serum anti-GAD antibodies were positive (62.9 IU/ml Ref 0.0-5.0 IU/ml) consistent with Stiff Person Syndrome (SPS).Ice masks and benzodiazepines, taken at the onset of facial spasms, helped relieve symptoms but failed to prevent episodes. A trial of IVIG and rituximab was also ineffective. Plasma exchange lessened the intensity of the facial spasms; but, it was only with the use of cannabis that the patient endorsed near complete resolution of her symptoms.
Discussion: Stiff person syndrome is a rare progressive disease affecting the nervous system which manifests with muscle stiffness, rigidity and painful spasms. It is categorized either as auto-immune, paraneoplastic or idiopathic in origin. Paraneoplastic SPS is diagnosed by detection of autoantibodies against GAD in the CSF. Treatment of the underlying cancer has been shown to reduce GAD titers and improve symptoms. Symptomatic management involve the use of benzodiazepines and muscle relaxants such as baclofen. In treatment resistant cases, rituximab, plasmapheresis and IVIG are often used. Our patient remained resistant to all of these conventional treatments.
Conclusions: Medical Marijuana can be used in paraneoplastic stiff person syndrome cases that are resistant to conventional treatment such as benzodiazepines, rituximab, IVIG and plasma exchange.