Severe Lumbar Stenosis Masquerading as Progression in Stiff Person Syndrome
Objective:
To describe a case of severe lumbar stenosis occurring in the context of a person with stiff person syndrome (SPS) who has concomitant hyperlordosis.
Background:
SPS is a rare, autoimmune neurological condition that most often presents with intermittent spasms, stiffness, and ambulatory dysfunction. Over time, people with SPS can develop lumbar hyperlordosis which is a hallmark sign on musculoskeletal exam. Other musculoskeletal changes can occur resulting in acute or chronic back pain that can be mistaken as progression of SPS.
Design/Methods:
Case report.
Results:
A 63-year-old woman developed insidious onset of stiffness, falls, and incoordination. Her exam demonstrated spasticity in lower extremities, hyperreflexia, and limb dysmetria. Initial MRIs were unremarkable. She continued to worsen and eventually was diagnosed with SPS; testing showed anti-GAD65 antibody at 19580 IU/mL. Upon re-examination, the patient was noted to have moderate hyperlordosis along with her previously noted findings. Muscle relaxers and intravenous immunoglobulin therapy (IVIG) were initiated, and symptoms remained stable until 2010, when patient reported worsening low back pain and imbalance. Due to suspected progression in her SPS, IVIG was stopped and mycophenolate mofetil was started. In 2014, her symptoms again worsened, and she underwent plasma exchange therapy with improvement in symptoms outside of her back pain. The patient also noted increasing lumbar radiculopathy that was further assessed by MRI which demonstrated severe lumbar stenosis secondary to spondylolisthesis. She underwent lumbar spine surgery. Post-operative lumbar hyperlordosis was less severe and her severe back and radicular pain resolved. Serial MRIs will be shown pre-and-post surgery.
Conclusions:
We present a case in which an SPS patient developed worsening back pain and stiffness with increasing hyperlordosis in the setting of severe lumbar stenosis. Clinicians should be aware of non-SPS related structural changes that can masquerade as progression in SPS especially since surgical intervention may be needed versus escalation in immune-based treatment.