Editors' Note: Association of Group A Streptococcus Exposure and Exacerbations of Chronic Tic Disorders: A Multinational Prospective Cohort Study

Abstract

In “Association of Group A Streptococcus Exposure and Exacerbations of Chronic Tic Disorders: A Multinational Prospective Cohort Study,” Martino et al. followed 715 children with chronic tic disorders (CTD) for up to 16 months and found that there was no significant association between group A streptococcus (GAS) pharyngeal exposures and tic exacerbations, although group A streptococcus exposure was associated with exacerbation of ADHD symptoms. On behalf of the European Immuno-Neuropsychiatric Association Scientific and Medical Advisory Group, Ubhi et al. praised the study but pointed out that because most patients had a previous diagnosis of Tourette syndrome, making it unlikely their tics were immune-mediated, these findings should not be used to refute the existence of immune-mediated tics or extrapolated to conclude immune-mediated tics are not associated with GAS exposure. Martino agreed that CTD are distinct from pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections (PANS/PANDAS) but noted there is growing evidence that CTD may be the result of immune-mediated mechanisms triggered by genetics and environmental exposures. Martino et al. and Ubhi et al. suggested there is a need for additional investigation into the relationship between GAS exposure and ADHD symptoms. In “Association of Group A Streptococcus Exposure and Exacerbations of Chronic Tic Disorders: A Multinational Prospective Cohort Study,” Martino et al. followed 715 children with chronic tic disorders (CTD) for up to 16 months and found that there was no significant association between group A streptococcus (GAS) pharyngeal exposures and tic exacerbations, although group A streptococcus exposure was associated with exacerbation of ADHD symptoms. On behalf of the European Immuno-Neuropsychiatric Association Scientific and Medical Advisory Group, Ubhi et al. praised the study but pointed out that because most patients had a previous diagnosis of Tourette syndrome, making it unlikely their tics were immune-mediated, these findings should not be used to refute the existence of immune-mediated tics or extrapolated to conclude immune-mediated tics are not associated with GAS exposure. Martino agreed that CTD are distinct from pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections (PANS/PANDAS) but noted there is growing evidence that CTD may be the result of immune-mediated mechanisms triggered by genetics and environmental exposures. Martino et al. and Ubhi et al. suggested there is a need for additional investigation into the relationship between GAS exposure and ADHD symptoms.