[Serum levels of 25-hydroxyvitamin D in children with tic disorders]

OBJECTIVE

To examine serum 25-hydroxyvitamin D levels in children with tic disorders (TD) and to explore the relationship between vitamin D level and TD.

METHODS

One hundred and thirty-two children who were diagnosed with TD between November 2016 and May 2017 were enrolled as the TD group, including 8 cases of Tourette syndrome, 32 cases of chronic TD, and 92 cases of transient TD. One hundred and forty-four healthy children served as the control group. Peripheral venous blood samples were collected from each child. Serum levels of 25-hydroxyvitamin D were measured using HPLC-MS/MS. The categories of vitamin D status based on serum 25-hydroxyvitamin D level included: normal (>30 ng/mL), insufficiency (10-30 ng/mL) and deficiency (<10 ng/mL).

RESULTS

Mean serum level of 25-hydroxyvitamin D in the TD group was significantly lower than that in the control group (P<0.01). The rate of vitamin D insufficiency or deficiency in the TD group was significantly higher than in the control group (P<0.01). Mean serum level of 25-hydroxyvitamin D in the transient tic group was higher than in the TS group (P<0.05).

CONCLUSIONS

Vitamin D insufficiency or deficiency might be associated with the development of TD, and the level of serum 25-hydroxyvitamin D might be related to the classification of TD.

Detection of anti-streptococcal, antienolase, and anti-neural antibodies in subjects with early-onset psychiatric disorders

INTRODUCTION

Infection with group A Streptococcus (StrepA) can cause post-infectious sequelae, including a spectrum of childhood-onset obsessive-compulsive (OCD) and tic disorders with autoimmune origin (PANDAS, Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal Infections). Until now, no single immunological test has been designed that unequivocally diagnoses these disorders. In this study, we assessed the detection of serum antibodies against human brain enolase (AE), neural tissue (AN) and Streptococcus (AS) as a laboratory tool for the diagnosis of early-onset psychiatric disorders.

METHODOLOGY

Serum antibodies against human brain enolase, total brain proteins, and total proteins from StrepA were detected by ELISA in 37 patients with a presumptive diagnosis of PANDAS and in 12 healthy subjects from Mexico and Cuba.

RESULTS

The antibody titers against human brain enolase (AE) and Streptococcal proteins (AS) were higher in patients than in control subjects (t-student, tAE=-2.17, P=0.035; tAS=-2.68, P=0.01, n=12 and 37/group, df=47, significance level 0.05), while the neural antibody titers did not differ between the two groups (P(t)=0.05). The number of subjects (titers> meancontrol + CI95) with simultaneous seropositivity to all three antibodies was higher in the patient group (51.4%) than in the control group (8.3%) group (X2=5.27, P=0.022, df=1, n=49).

CONCLUSIONS

The simultaneous detection of all three of these antibodies could provide valuable information for the etiologic diagnosis of individuals with early-onset obsessive-compulsive disorders associated with streptococcal infection and, consequently, for prescribing suitable therapy.

[Epidemiological investigation of tic disorders among pupils in the Shunde Longjiang area, and their relationship to trace elements]

OBJECTIVE

To investigate the epidemiological characteristics of tic disorders (TD) among pupils in the Shunde Longjiang area, and their relationship to trace elements.

METHODS

A cross-sectional study of 4062 children aged 6-12 years, who were selected from the Shunde Longjiang area by stratified cluster sampling to investigate the epidemiological characteristics of TD, was conducted, and blood concentrations of trace elements in children with TD were determined. Forty normal children were selected as controls.

RESULTS

The overall prevalence rate of TD was 2.98%; the prevalence rates of transient tic disorder, chronic motor or vocal tic disorder and Tourette's syndrome were 3.62%, 2.39% and 1.21% respectively. Boys had a significantly higher prevalence rate of TD than girls (3.92% vs 1.96%; P<0.05). There were no significant differences in blood copper, manganese and magnesium levels between children with TD and normal children (P>0.05), however, children with TD had a significantly increased blood lead level and significantly decreased blood zinc and iron levels compared with the normal children (P<0.05). No significant differences in trace elements were found between children with different subtypes of TD (P>0.05).

CONCLUSIONS

TD is common in children aged 6-12 years and more prevalent in boys than in girls. High blood lead level and zinc and iron deficiencies may be one of the causes of TD, and thus should be considered during therapy.

Plasma kynurenine and related measures in tic disorder patients

OBJECTIVE

Increased plasma kynurenine has been reported in tic disorder patients, and this observation has been suggested to be indicative of immune dysregulation. In the present study, we examined plasma levels of kynurenine and related molecules in a group of tic disorder patients.

METHODS

Plasma concentrations of tryptophan, kynurenine, cortisol, and neopterin were determined in Dutch tic disorder patients (N = 59), and healthy volunteers (N = 32). Group means were compared and age-controlled intra-individual correlations between tic severity and plasma levels of these molecules were examined.

RESULTS

No significant differences were found between patient and control groups in plasma levels of tryptophan, kynurenine, and cortisol concentrations, nor in the kynurenine/tryptophan ratio. However, neopterin was significantly (p = 0.035) higher in patients (mean = 5.13 nmol/l) than in controls (mean = 3.30 nmol/l). Plasma levels of these molecules did not correlate with tic severity, with the exception of tryptophan (r = -0.289, p = 0.049). In patients, plasma neopterin correlated with kynurenine (r = 0.438, p = 0.002); in healthy subjects, tryptophan correlated with kynurenine (r = 0.670, p < 0.001).

CONCLUSION

While the observed elevation in plasma neopterin is consistent with immune activation in a subset of tic disorder patients, metabolism of tryptophan through the kynurenine pathway appears to be unaltered in tic disorder patients.

Increased seroreactivity in tic disorder patients to a 60 kDa protein band from a neuronal cell line

In tic disorders, increased seroreactivity against neuronal antigens has been demonstrated, without performing molecular characterization of antigens. Here, unselected patients with a tic disorder were compared with healthy controls, autistic disorder (AD), and obsessive-compulsive disorder (OCD) patients. Seroreactivity against neuroblastoma cells was analyzed by Western blot. Anti-60 kDa binding occurred significantly more frequently in tic disorder patients (67.1%) than in AD (40.0%), OCD (40.0%) and healthy controls (41.9%). Sequence analysis of the 60 kDa protein band identified this as a ubiquitous heat shock protein. However, the involvement of other autoantigens with a molecular weight of 60 kDa cannot be excluded.

Whole blood serotonin in juvenile obsessive-compulsive disorder

Whole blood serotonin (5-HT) concentration was assessed in 16 children and adolescents with severe obsessive-compulsive disorder (OCD) and in 14 normal adolescent controls. There was no difference in blood 5-HT content between the OCD patients and the normal controls. However, the OCD patients with a family history of OCD had significantly higher blood 5-HT levels than did either the OCD patients without a family history of OCD or the normal controls. Blood 5-HT content was not associated with a history of major depressive disorder or chronic tic disorder. These preliminary results suggest that studies of serotonergic functioning in OCD may need to control for family history of OCD and that blood 5-HT may be a useful biochemical measure in family-genetic studies of OCD.

[Haloperidol. Plasma monitoring and hormonal effects of treatment]

Therapeutic plasma monitoring of haloperidol, a major neuroleptic, measured by radioimmunoassay, has shown a rather good correlation between plasma level and dosage but with large interindividual variation in children as in adults; age seems not to have any effect on haloperidol metabolism. 80% of subjects present a concomitant prolactin levels variation, whereas in 20% no prolactin response is found. During acute kinetics of either a 10 mg oral haloperidol administration or a 250 mg intramuscular haloperidol decanoate injection, a parallel elevation of prolactin, cortisol, immunoreactive bêta-endorphin and bêta-lipotropin plasma levels occur, at the same time as haloperidol plasma levels. Those rise with a good equivalence between the two doses of the two forms.