Krauthammer A, et al. - A retrospective review was performed to better characterize the subgroup of ataxia telangiectasia (AT) patients with elevated IgM levels (EIgM). This retrospective review was conducted on 46 patients followed from January 1986 to January 2015 at the Israeli National AT Center. Researchers reviewed demographic, clinical, radiological, laboratory data and compared the results between AT patients with EIgM and patients with normal IgM levels (NIgM). Results of this study suggested that EIgM in AT patients indicates a more severe phenotype that likely results from a specific immune dysfunction. They reported that EIgM in AT ought to be considered a unique AT phenotype that might need different management.