Kantarci, Orhun H.

Background: In multiple sclerosis (MS), the relapse rate declines during pregnancy and increases during the first three months post-partum before returning to the pre-pregnancy rate. It is unknown whether pregnancy impacts the risk of clinical conversion in those within the presymptomatic period. Objectives: We investigate the impact of pregnancy on developing a clinical event in women diagnosed with radiologically isolated syndrome (RIS). Methods: All women with RIS underwent clinical and radiological assessments as part of an observational, prospective, longitudinal study. Clinical and MRI outcomes were analyzed during and after pregnancy. Subjects who became pregnant were compared with an age-matched female RIS group who did not become pregnant during the same follow-up period. Results: A total of 60 women with RIS were followed for up to seven years. Among them, seven became pregnant and were compared with 53 age-matched control women with RIS who did not become pregnant during the observation period. A significantly shorter time of conversion to the first neurological event was observed in the pregnant group [15.3 months (10–18)] compared with the non-pregnant controls [35.7 months (8–76)], yielding an absolute difference of 20.4 months ( p<0.05). The mean (SD) number of active lesions on a subsequent brain MRI scan was significantly higher in the pregnant group [3.2 (±1.7)] compared with the control group [1.8 (±0.6)]. Conclusions: The risk for clinical conversion from RIS to a clinical event and new MRI disease activity seems to be influenced by pregnancy. Pregnancy related physiological changes could operate as early as the presymptomatic period in patients with MS.

Genome-wide association studies have identified an association between two intronic single nucleotide polymorphisms (SNPs), rs12722489 and rs2104286, in the interleukin-2 receptor alpha-chain gene ( IL2RA) and susceptibility to multiple sclerosis (MS). We studied these SNPs in association with susceptibility to and severity of MS in a population-based cohort of 220 patients from Olmsted County, Minnesota, compared with 442 matched controls. We sequenced the exons, splice sites and 5’ and 3’ untranslated regions in 27 randomly selected MS patients (powered for allele frequency ≥0.04) to search for mutations. No novel missense mutation was identified. Two patients (7.5%) had an exon 2 SNP ( rs4308625) and two patients had an exon 4 SNP ( rs2228149), both synonymous.

Primary progressive multiple sclerosis (PPMS), relapsing remitting MS (RRMS) and acute disseminated encephalomyelitis (ADEM) are clinically and immunopathogenetically distinct phenotypes of inflammatory demyelinating disorders of the central nervous system. Progression following RRMS is well described as secondary progressive MS. We report a patient with unexpected transition from long established PPMS to clinically and radiologically active RRMS after an ADEM-like fulminant demyelinating episode despite an immunosuppressive treatment preceding relapses. We note clearly accelerated brain atrophy after the RRMS course ensues. The unique disease course in this patient illustrates the dissociation of the biology and disability impact of relapses and progression.

Background: Association of the HLA-DRB1*1501 allele with multiple sclerosis is well established, but its association with neuromyelitis optica has only been evaluated in small populations. Methods: We performed a case-control genetic association study to evaluate the association of HLA-DRB1*1501 with neuromyelitis optica. The single nucleotide polymorphism rs3135388, which tags HLA-DRB1*1501, was genotyped in 164 patients with neuromyelitis optica, 220 patients with multiple sclerosis and 959 controls matched for age, gender and ethnicity. Genotyping for rs3135388 was performed by Taqman-based 5' nuclease assay. Results: Rs3135388*A was positively associated with multiple sclerosis (OR = 3.93; 95% CI = 2.58—5.97, p = 1.18 × 10 -09 ) but negatively associated with NMO (OR = 0.57; 95% CI = 0.36—0.91, p = 0.01). Conclusions: Multiple sclerosis and neuromyelitis optica differ in their associations with DRB1*1501.