Role of Immunotherapy in Down Syndrome Disintegrative Disorder (DSDD)

Objective To describe case series of patients with DSDD, successfully treated immunotherapy including Intravenous Immunoglobulin (IVIG) at a single academic center. Background Down syndrome is the most common chromosomal disorder, and in cases, due to trisomy chromosome 21. DSDD underrecognized, rapidly progressive neuropsychiatric various postulated etiology psychological stress, primary psychiatric disorder autoimmunity. Design/Methods Case-1: A 20-year-old fun loving female trisomy-21 infantile spasms started having complex partial seizures, hallucinations, speech regression, tics, abnormal head movement obsessive-compulsive behavior. Case-2: cheerleader trisomy-21, rapid regression language, cognition, social skills agitation over one year. Case-3: 22-year-old dancer subacute onset depression, sleep changes, anorexia Results MRI brain cerebrospinal fluid (CSF) studies were normal negative autoimmune encephalitis panel. Serum thyroglobulin thyroid peroxidase antibody high. Prolonged oral steroid therapy helped but caused adverse effects. She was able return her premorbid baseline chronic IVIG every 10 weeks. CSF normal. panel, negative. Pulse IV steroids improved symptoms, however she regressed after stopping steroids. 6 weeks along electroconvulsive neurological symptoms. EEG showed elevated white blood cell count. Thyroid antimicrosomal One dose significant improvement symptoms for Conclusions should be considered down regression. It often associated positive suggesting immune mediated etiology. Various treatments have been reported literature steroid, IVIG, mycophenolate rituximab selected patient