Clinical profile and plasma Vitamin B6 levels in children with Tourette Syndrome

Abstract Background Tourette syndrome is a childhood-onset neuropsychiatric disorder characterised by recurrent motor and vocal tics. It shows a marked male predominance and is frequently associated with comorbid conditions such as attention-deficit/hyperactivity disorder (ADHD) and obsessive– compulsive disorder (OCD). Histaminergic dysregulation in the brain has been proposed as one of the mechanisms underlying Tourette syndrome. Vitamin B6, a key cofactor in histamine metabolism, may therefore play a contributory role in its pathophysiology. Method The clinical features of 25 children diagnosed with Tourette syndrome were assessed using the Yale Global Tic Severity Scale. Plasma vitamin B6 levels were measured using enzyme-linked immunosorbent assay (ELISA) and compared with those of a control group. Result Most participants were males, and 16% had comorbid ADHD or OCD. The most common motor tics were eye blinking, shoulder shrugging, head jerking, and orofacial movements. Frequent vocal tics included throat clearing, sniffing, uttering syllables, and breathing-related tics. Coprolalia was observed in four children. The median plasma vitamin B6 level in the Tourette syndrome group was 25.01ng/ml, which was significantly lower than the 36.33ng/ml in the control group (Mann–Whitney U = 225, p = 0.03). The rank-biserial correlation indicated a moderate effect size (r = 0.35). Conclusion Tourette syndrome in children predominantly affects males and is commonly associated with ADHD and OCD. Coprolalia-a clinically distressing symptom - was present only in a small subgroup. The lower plasma vitamin B6 levels observed in children with Tourette syndrome suggest a possible role for vitamin B6 in disease pathogenesis, potentially through its involvement in histaminergic and GABAergic neurotransmission, as well as in the modulation of neuroinflammatory processes.