A list of other members of the Italian Tourette Syndrome Study Group can be found in Appendix S1 (supporting information online).
The relationship between group A streptococcal infections and Tourette syndrome: a study on a large service-based cohort
Version of Record online: 17 JUN 2011
© The Authors. Developmental Medicine & Child Neurology © 2011 Mac Keith Press
Developmental Medicine & Child Neurology
Volume 53, Issue 10, pages 951–957, October 2011
How to Cite
MARTINO, D., CHIAROTTI, F., BUTTIGLIONE, M., CARDONA, F., CRETI, R., NARDOCCI, N., OREFICI, G., VENESELLI, E., RIZZO, R. and ON BEHALF OF THE ITALIAN TOURETTE SYNDROME STUDY GROUP (2011), The relationship between group A streptococcal infections and Tourette syndrome: a study on a large service-based cohort. Developmental Medicine & Child Neurology, 53: 951–957. doi: 10.1111/j.1469-8749.2011.04018.x
This article is commented on by Gilbert on pages 883884 of this issue.
- Issue online: 6 SEP 2011
- Version of Record online: 17 JUN 2011
- PUBLICATION DATA Accepted for publication 11th April 2011. Published online 17th June 2011.
Aim To evaluate the relationship between diagnosis and clinical course of Tourette syndrome and group A Streptococcus (GAS).
Method GAS infections, anti-streptococcal, and anti-basal ganglia antibodies (ABGA) were compared between 168 patients (136 males, 32 females) with Tourette syndrome; (median [range] age [25th–75th centile] 10y [8–11y]); median Tourette syndrome duration (25th–75th centile), 3y (1y 3mo–5y 9mo) and a comparison group of 177 patients (117 males, 60 females) with epileptic or sleep disorders median age [25th–75th centile], 10y [8y–1y 6mo]). One hundred and forty-four patients with Tourette syndrome were followed up at 3-month intervals; exacerbations of tics, obsessive–compulsive symptoms, and other psychiatric comorbidities were defined by a bootstrap procedure. The effect of new GAS infections and identification of new ABGA upon risk of exacerbation was assessed using logistic regression analysis.
Results Cross-sectionally, patients with Tourette syndrome exhibited a higher frequency of GAS infection (8% vs 2%; p=0.009), higher anti-streptolysin O (ASO) titres (246 [108–432] vs 125 [53–269]; p<0.001), and higher ABGA frequency (25% vs 8%; p<0.001) than the comparison group. On prospective analysis, ASO titres were persistently elevated in 57% of patients with Tourette syndrome; however, new infections or newly identified ABGA did not predict clinical exacerbations (all p>0.05).
Interpretation Patients with Tourette syndrome might be more prone to GAS infections and develop stronger antibody responses to GAS, probably as a result of underlying immune dysregulation. New GAS infections are unlikely to exert, years after their onset, a major effect upon the severity of neuropsychiatric symptoms.