To characterize which clinical phenotypes of SPSD require more immunotherapy or symptomatic treatment.

Individuals with SPSD evaluated at the Johns Hopkins SPS Center from 1997-2022 are followed through a longitudinal cohort study. Data collection occurs during clinic visits and includes demographic data, disease characteristics, laboratory studies, exam findings, and treatment. Treatment is classified as immunotherapy or symptomatic (pharmacological and non-pharmacological) therapy. All current and historical treatments for a patient were included in the descriptive analysis.

Ultimately, 235 people with a diagnosis of SPSD meeting criteria for a clinical phenotype (155 classic SPS, 45 SPS-plus, 16 PERM, 11 CA, 8 partial-SPS) were included. Mean age was 58±14 years, with the majority female(75%) and white(69%). For immunotherapy, 94% of PERM, 82% of SPS-plus, 75% of classic SPS, 73% of CA, and 38% of partial-SPS patients were prescribed immunotherapy, most commonly intravenous immunoglobulin, rituximab, and/or plasmapheresis. All PERM, 98% of SPS-plus, 97% of classic SPS, 88% of partial-SPS, and 45% of CA patients were prescribed at least one symptomatic therapy, most commonly benzodiazepines and/or baclofen.  

Individuals with PERM, SPS-plus, and classic SPS were prescribed more immunotherapy and symptomatic therapies. While people with CA were more likely to trial immunotherapy, those with a partial-SPS were more likely to trial symptomatic medications. Further studies will evaluate if perceptions on phenotype clinical severity or lack of effective interventions to target particular symptoms may lead to these differences in clinical care.