GP231 Review of investigations carried out during the first presentation of acquired demyelinating sydnromes over a ten year period

Aims A first episode of suspected demyelination presents a diagnostic challenge often having non-specific signs which overlap with other inflammatory white matter, neurometabolic and genetic disorders. The first episode may be a presentation of acute disseminated encephalomyelitis, multiple sclerosis, optic neuritis, transverse myelitis or NMO spectrum disorders1,2. Associated morbidity and mortality of each is vastly different. Gaining accurate information through appropriate investigation is vital for appropriate treatment and counselling. There is currently no national or international guideline for investigation of an acute demyelinating episode. Methods Retrospective review of all cases of a first demyelinating event over a 10 year period (2008 – 2018) at Cork University Hospital. Laboratory investigations, imaging and clinic letters were reviewed. Results In total eighteen cases were reviewed. Eventual diagnoses were 7 ADEM, 4 ADEM with transverse myelitis, 4 Multiple Sclerosis and 3 Optic Neuritis. Median presentation age was 6 years (1 year 4 months - 15 years 10 months). WCC and CSF microscopy was done in 100%. CRP and ESR done in 89% and 28% respectively. Investigations for bacterial and viral causes either on serum, CSF or swabs was inconsistent varying between 11–83%. CSF antibodies, including anti MOG, anti-NMDA, Aquaporin 4 and anti voltage gated potassium channel antibodies were sent in 6–39% of cases dependant on test. Oligoclonal bands were sent in 83%. Imaging was undertaken in all cases with seventeen having an MRI Brain. Median time to MR brain was 1 day (0 days – 6 days). Fourteen cases had a MR spine with median time to spinal imaging of 2 days (1 day – 11 days). Conclusion This review highlights the variable approach to investigation of suspected demyelination. The wide differential and need for prompt treatment to prevent long term neurological disability means there are multiple complex investigations required within a short time period. The laboratory investigations and neuroimaging required are labour intensive and incur significant financial cost. This is of particular importance in children, many of whom will require sedation and at times general anaesthetic to ensure successful obtaining of samples. The availability of a local protocol would guide clinicians investigation when faced with an unfamiliar presentation under significant time pressure. It would ensure appropriate and timely investigation enabling appropriate treatment and counselling.