title: Increased serum levels of interleukin-12 and tumor necrosis factor-alpha in Tourette's syndrome.
abstract: BACKGROUND
  The hypothesis that common infections can modulate the onset and course of tic disorders and early-onset obsessive-compulsive disorder (OCD) in pediatric populations is longstanding. To date, most investigations have focused on the hypothesis of molecular mimicry and humoral immune responses. This study was carried out to investigate whether cytokines associated with the innate immune response or T cell activation were altered under baseline conditions and during periods of symptom exacerbation.
  
  
  METHODS
  Forty-six patients with Tourette's syndrome and/or early-onset OCD, aged 7-17 years, and 31 age-matched control subjects participated in a prospective longitudinal study. Ratings of clinical severity and serum were collected at regular intervals, and serum concentrations of 10 cytokines were measured repeatedly.
  
  
  RESULTS
  Interleukin-12 and tumor necrosis factor alpha concentrations at baseline were elevated in patients compared with control subjects. Both of these markers were further increased during periods of symptom exacerbation.
  
  
  CONCLUSIONS
  These findings suggest that symptom exacerbations are associated with an inflammatory process propagated by systemic and local cytokine synthesis that might involve the central nervous system. We conclude that, in the future, longitudinal studies of children with neuropsychiatric disorders should examine the involvement of innate and T cell immunity.
authors.affiliation: Child Study Center, Yale University School of Medicine, New Haven, CT 06520-7900, USA. james.leckman@yale.edu
authors.forename: James F
authors.initials: JF
authors.lastname: Leckman
authors.forename: Liliya
authors.initials: L
authors.lastname: Katsovich
authors.forename: Ivana
authors.initials: I
authors.lastname: Kawikova
authors.forename: Haiqun
authors.initials: H
authors.lastname: Lin
authors.forename: Heping
authors.initials: H
authors.lastname: Zhang
authors.forename: Holger
authors.initials: H
authors.lastname: Krönig
authors.forename: Syed
authors.initials: S
authors.lastname: Morshed
authors.forename: Salina
authors.initials: S
authors.lastname: Parveen
authors.forename: Heidi
authors.initials: H
authors.lastname: Grantz
authors.forename: Paul J
authors.initials: PJ
authors.lastname: Lombroso
authors.forename: Robert A
authors.initials: RA
authors.lastname: King
mesh_terms: D000293:Adolescent; D016022:Case-Control Studies; D002648:Child; D016207:Cytokines / Q000097:blood; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods; D005260:Female; D006801:Humans; D018664:Interleukin-12 / Q000097:blood*; D008137:Longitudinal Studies; D008297:Male; D011446:Prospective Studies; D005879:Tourette Syndrome / Q000097:blood*; D014409:Tumor Necrosis Factor-alpha / Q000378:metabolism*
chemical_list: D016207:Cytokines; D014409:Tumor Necrosis Factor-alpha; D018664:Interleukin-12