Acute Demyelinating Syndromes: A report of child neurology department of Sfax University Hospital.

INTRODUCTION The yearly incidence of Acute Demyelinating Syndromes (ADS) in a multiethnic cohort of children published by Langer-Gould and al in 2011 was estimated at about 1.66 per 100,000. Nevertheless, the real incidence for these disorders is still underestimated as the iterative revision for diagnosis criteria have failed to classify a significant number of children with ADS. PURPOSE This work was aimed to describe clinical and paraclinical characteristics of ADS in a pediatric population. MATERIAL AND METHODS Demographic, clinical and paraclinical data of 42 children (24 females; 18 male; SR = 1.33), were collected from the medical records of patients admitted to the child neurology department of Sfax University Hospital between 2008 and 2021 for clinical events with presumed inflammatory origin. Next, patients were categorized as per M. N. Nouri and al. up dated classification for ADS. Finally, characteristics of different ADS categories were compared. RESULTS The mean age onset was 6 years (± 3.5 years). For a mean follow-up period of 28 months, 69% of patients had a monophasic course. ADS in our pediatric population were Acute disseminated encephalomyelitis (ADEM) (36%), Clinically isolated syndrome (CIS) (24%), Multiple sclerosis (MS) (19%), Neuromyelitis optica spectrum disorder (NMOSD) (7%), Myelin oligodendrocyte glycoprotein antibodies-associated diseases (MOGAD) (2%) and Recurrent demyelinating disease not otherwise specified (RD-NOS) (10%). At presentation, patients showed different clinical picture according to ADS-subtype with more patients with epileptic seizure in ADEM-group (53.3%), optic neuritis in CIS-group (70%), motor deficit in MS-group (62.5%), area postrema syndrome in NMOSD-group (33.3%) and vesico-sphincter dysfunction in RD-NOS-group (75%). Among patients presenting with visual impairment (21.4%), Visual evoked potential (VEP) guided the diagnosis of NMOSD in 22.2% by objectifying axonal optic nerve damage. Different ADS subtypes were identified according to MRI results in 100% of ADEM-patients and 75% of MS-patients and on antibody testing in three patients. The ADS-subtype was recognized based on antibody testing in three patients. Two patients from CIS-group: the first with isolated optic neuritis (ON) was positive for antiaquaporin 4 antibodies (anti-AQP4) and the other with clinically polyfocal ADS was positive for antinuclear antibodies (ANA) type anti-RNP. The remaining patients who presented with ADEM-phenotype was positive for anti-myelin oligodendrocyte glycoprotein (anti-MOG). SIGNIFICANCE Recognizing distinctive features of each ADS category may improve diagnosis accuracy as well as the indication of suitable treatment.