Introduction In patients with stiff person syndrome (SPS) and related syndromes the objective of treatment is to provide symptomatic relief from stiffness and spasms. Intravenous immunoglobulin (IVIG) therapy is a commonly prescribed treatment for SPS patients, however there is no widely used method of assessing the effectiveness of IVIG treatment in SPS. This issue has been addressed by the introduction of the Birmingham Response to IVIG Treatment (BRIT) scale.

Methods Data from 21 patients was retrospectively analysed to explore a number of outcomes including: time to diagnosis, antibody statuses, clinical phenotype, first symptom, distribution of stiffness and EMG changes and treatments received.

9/21 patients had pre- and post-IVIG BRIT data, which was analysed using paired t-tests.

Results Average time from first presentation to diagnosis was 37 months (range: 1–180 months). Anti-GAD antibody was positive in 18/21 (85.7%) with two glycine positive and one seronegative patient. EMG changes were found in 5/15 (33.3%) of patients.

Both functional ability score (p=0.0422) and quality of life score (p=0.0175) improved with statistical significance after receiving IVIG treatment.

Conclusion IVIG treatment is effective in improving quality of life and functional ability in SPS patients. Treatment response can be comprehensively measured using the BRIT scale.