Abstract Details

Title Misdiagnosis of Stiff Person Syndrome Spectrum Disorders: Identifying the Most Common Culprits

Topic Autoimmune Neurology

Presentation(s) P4 - Poster Session 4 (8:00 AM-9:00 AM)

Poster/Presentation
Number 6-022

Objective

To characterize common misdiagnoses in a cohort of patients with Stiff Person Syndrome Spectrum Disorders (SPSD) and identify clinical features associated with misdiagnosis.

Background SPSD are a group of rare, disabling neuroimmunological disorders that can take several years to diagnose, often secondary to clinicians’ lack of awareness of the associated signs and symptoms. The classic SPS phenotype is associated with insidious worsening of lower extremity stiffness/rigidity, while SPS-plus includes classic features with cerebellar and/or brainstem involvement.

Design/Methods The Johns Hopkins SPS center’s longitudinal observational database was used, which contains clinical characteristics of people with SPSD. Patient’s charts were also reviewed to identify prior misdiagnoses and tabulated. Similar conditions were combined into categories (e.g., “Cervical spondylosis” and “Myelopathy” into “Spondylotic myelopathy”). Demographic factors were evaluated via univariate analysis for association with prior misdiagnoses. Calculated odds ratios (OR) were performed for any clinical factors associated with misdiagnosis across the full cohort, and for both Classic SPS and SPS-plus phenotypes.

Results Of 240 patients diagnosed with SPSD, 145 (58%) had a prior misdiagnosis. The most common misdiagnoses were spondylotic myelopathy (22,16%), neuropathy (18,12%), movement disorder (12,8%), and conversion disorder (11,7%). Age, race/ethnicity, and sex were not associated with misdiagnosis. The clinical characteristics associated with misdiagnosis were upper extremity stiffness and/or spasms (OR 3.86, 95% CI 2.63-5.88), and this association was strongest for Classic SPS (OR 8.40, 95% CI 6.35-10.44). In SPS-plus patients, brainstem (OR 7.00, 95% CI 5.38-8.62) and cerebellar symptoms (OR 3.27, 95% CI 1.83-4.71) were associated with misdiagnosis.

Conclusions Most of our patients were found to have prior misdiagnoses. These misdiagnoses were associated with presentations involving the upper extremities and symptoms localizable to infratentorial regions. Increased awareness by clinicians of the signs and symptoms in SPSD may help prevent misdiagnoses and unnecessary procedures, and expediate initiation of treatment.

Authors/Disclosures
Shuvro Roy, MD (University of Washington) PRESENTER	Dr. Roy has received personal compensation in the range of $500-$4,999 for serving on a Scientific Advisory or Data Safety Monitoring board for Amgen. Dr. Roy has received personal compensation in the range of $500-$4,999 for serving on a Scientific Advisory or Data Safety Monitoring board for Genentech. Dr. Roy has received personal compensation in the range of $500-$4,999 for serving on a Scientific Advisory or Data Safety Monitoring board for TG Therapeutics. Dr. Roy has received personal compensation in the range of $500-$4,999 for serving on a Scientific Advisory or Data Safety Monitoring board for Alexion. The institution of Dr. Roy has received research support from The Siegel Rare Neuroimmune Association.
Yujie Wang, MD (UW Northwest)	Dr. Wang has received personal compensation in the range of $500-$4,999 for serving as a Consultant for TG Therapeutics. The institution of Dr. Wang has received research support from Genentech. The institution of Dr. Wang has received research support from uniQure. The institution of Dr. Wang has received research support from NIH/NINDS.
Scott D. Newsome, DO, FAAN (Johns Hopkins Hospital)	Dr. Newsome has received personal compensation in the range of $10,000-$49,999 for serving on a Scientific Advisory or Data Safety Monitoring board for Genentech. Dr. Newsome has received personal compensation in the range of $500-$4,999 for serving on a Scientific Advisory or Data Safety Monitoring board for Novartis. Dr. Newsome has received personal compensation in the range of $500-$4,999 for serving on a Scientific Advisory or Data Safety Monitoring board for TG Therapeutics. The institution of Dr. Newsome has received research support from Biogen. The institution of Dr. Newsome has received research support from Genentech/Roche. The institution of Dr. Newsome has received research support from Department of Defense. The institution of Dr. Newsome has received research support from Patient Centered Outcomes Research Institute. The institution of Dr. Newsome has received research support from National MS Society. The institution of Dr. Newsome has received research support from Lundbeck. The institution of Dr. Newsome has received research support from Sanofi. The institution of Dr. Newsome has received research support from Kyverna Therapeutics. Dr. Newsome has received personal compensation in the range of $10,000-$49,999 for serving as a Lead PI for Clinical Trial with Roche.

��ɫ��

��ɫ��