10%; positive QAlb: 47

10%; positive QAlb: 47.1% vs. 89% of samples (N= 96), and the MRZ reaction, the most specific laboratory marker of MS known so far, in 100% (N= 29). If present at all, intrathecal IgG synthesis was low, often transient and mostly restricted to acute attacks. Intrathecal IgM synthesis was present in 21% and exclusively detectable during acute attacks. CSF WCC were elevated in 54% of samples (median 40 cells/l; range 6256; mostly lymphocytes and monocytes; > 100/l in 11%). Neutrophils were present in 71% of samples; eosinophils, activated lymphocytes, and plasma cells were seen only rarely (all < 7%). BloodCSF barrier dysfunction (as indicated by an elevated albumin CSF/serum ratio) was present in 46% of all samples (N= 79) and at least once in 48% of all patients (N= 67) tested. CSF alterations were significantly more frequent and/or more pronounced AQ-13 dihydrochloride in patients with acute spinal cord or brain disease than in patients with acute ON and varied strongly depending on attack severity. CSFl-lactate levels correlated significantly with the spinal cord lesions load (measured in vertebral segments) in patients with acute myelitis (p= 0.0099). An analysis of pooled data from the pediatric and the adult cohort showed a significant relationship of QAlb (p< 0.0005), CST TP (p< 0.0001), and CSFl-lactate (p< 0.0003) during acute attacks with age. Mouse monoclonal to CSF1 == Conclusion == MOG-IgG-associated EM in children is characterized by CSF features that are distinct from those in MS. With regard to most parameters, no marked differences between the pediatric cohort and the adult cohort analyzed in Part 1 were noted. Our findings are important for the differential diagnosis of pediatric MS and MOG-EM and add to the understanding of the immunopathogenesis of this newly described autoimmune disease. Keywords:MOG antibody-associated disease (MOGAD), Myelin oligodendrocyte glycoprotein (MOG), Antibodies, Encephalomyelitis, Cerebrospinal fluid, Lumbar puncture, Optic neuritis, Transverse myelitis, Neuromyelitis optica (Devic syndrome), NMO spectrum disorders, Brainstem encephalitis, Acute disseminated encephalomyelitis (ADEM), Children, Multiple sclerosis (MS), Oligoclonal bands == Introduction == Over the past few years, several studies using new-generation cell-based assays (CBA) have demonstrated a robust association of immunoglobulin G (IgG) autoantibodies targeting full-length, conformationally intact human myelin oligodendrocyte glycoprotein (MOG) with (mostly recurrent) optic neuritis (ON), myelitis, and brainstem encephalitis, as well as with neuromyelitis optica (NMO)-like and acute disseminated encephalomyelitis (ADEM)-like presentations, rather than with classic multiple sclerosis (MS) [111]. The suspected pathophysiological role of MOG-IgG was first described in children, who more often present with MOG-IgG-associated disorders than adults [1215]. Based on evidence from (a) immunological studies suggesting a direct pathogenic impact of MOG-IgG, (b) neuropathological studies demonstrating discrete histopathological features, (c) serological studies reporting a lack of aquaporin-4 (AQP4)-IgG in almost all MOG-IgG-positive patients, and (d) cohort studies suggesting differences in clinical and paraclinical presentation, treatment response, and prognosis, MOG-IgG is now considered to denote a disease entity in its own right, distinct from classic MS and from AQP4-IgG-positive NMO spectrum disorders (NMOSD) [1621], which is now often referred to as MOG-IgG-associated encephalomyelitis (MOG-EM) or MOG-IgG-associated autoimmune disease [11,22,23]. Several studies have shown that the proportion of patients with autoimmunity against MOG among all patients with inflammatory demyelinating CNS disorders is age-dependent with the highest seropositivity rates and highest MOG-IgG titers found in very young children [1,24,25]. ADEM-like disease is the predominant clinical presentation in young children, whereas in older children with MOG-IgG there is a shift toward ON, myelitis, and/or brainstem symptoms. MRI findings range from normal to widespread brain and spinal cord white and grey matter involvement [13]. So far, only limited data are available on the cerebrospinal fluid (CSF) profile in MOG-EM in pediatric patients. Previous studies were either based AQ-13 dihydrochloride on relatively small patient numbers, included mainly adult patients, and/or did not consider Caucasian patients. Moreover, all investigated only a small number of selected CSF parameters. In Part 1 of this article series, we report on the CSF findings in MOG-EM in adults [26]. For the present study, we systematically and comprehensively analyzed the results of 108 lumbar punctures AQ-13 dihydrochloride (LP) from a cohort of 80 pediatric patients of mainly Caucasian descent with MOG-IgG-associated EM. == Patients and methods == == Patients == Results from 108 lumbar punctures (LP) in 80 pediatric patients with MOG-EM were analyzed retrospectively. MOG-EM was defined as monophasic or relapsing acute ON, myelitis, brainstem encephalitis, or encephalitis associated.