Mycoplasma pneumoniae IgG positivity is associated with tic severity in chronic tic disorders

J Schnell, M Bond, N Moll, E Weidinger, B Burger, R Bond, A Dietrich, PJ. Hoekstra, A Schrag, D Martino, M Schwarz, U-X Meier, N Müller. Brain, Behavior, and Immunity. Vol 99, 2022. DOI: 10.1016/j.bbi.2021.10.012

• M. pneumoniae IgG positivity was not associated with the presence of CTD.
• M. pneumoniae IgG positivity was not associated with the first onset of tics.
• M. pneumoniae IgG positivity was significantly associated with higher tic severity.

“It is possible that M. pneumoniae infection influences tic severity in CTD or, that having more severe tics, increases the risk of infection. However, it is more likely that the association observed in this study reflects a propensity toward enhanced immune responses in people with CTD and that, rather than a causal relationship, infection and greater tic severity are indirectly linked via shared underlying immune mechanisms.”