Mycoplasma pneumoniae infection and Tourette's syndrome

1H-NMR-Based Metabolomics in Autism Spectrum Disorder and Pediatric Acute-Onset Neuropsychiatric Syndrome

We recently described a unique plasma metabolite profile in subjects with pediatric acute-onset neuropsychiatric syndrome (PANS), suggesting pathogenic models involving specific patterns of neurotransmission, neuroinflammation, and oxidative stress. Here, we extend the analysis to a group of patients with autism spectrum disorder (ASD), as a consensus has recently emerged around its immune-mediated pathophysiology with a widespread involvement of brain networks. This observational case-control study enrolled patients referred for PANS and ASD from June 2019 to May 2020, as well as neurotypical age and gender-matched control subjects. Thirty-four PANS outpatients, fifteen ASD outpatients, and twenty-five neurotypical subjects underwent physical and neuropsychiatric evaluations, alongside serum metabolomic analysis with 1H-NMR. In supervised models, the metabolomic profile of ASD was significantly different from controls (p = 0.0001), with skewed concentrations of asparagine, aspartate, betaine, glycine, lactate, glucose, and pyruvate. Metabolomic separation was also observed between PANS and ASD subjects (p = 0.02), with differences in the concentrations of arginine, aspartate, betaine, choline, creatine phosphate, glycine, pyruvate, and tryptophan. We confirmed a unique serum metabolomic profile of PANS compared with both ASD and neurotypical subjects, distinguishing PANS as a pathophysiological entity per se. Tryptophan and glycine appear as neuroinflammatory fingerprints of PANS and ASD, respectively. In particular, a reduction in glycine would primarily affect NMDA-R excitatory tone, overall impairing downstream glutamatergic, dopaminergic, and GABAergic transmissions. Nonetheless, we found metabolomic similarities between PANS and ASD that suggest a putative role of N-methyl-D-aspartate receptor (NMDA-R) dysfunction in both disorders. Metabolomics-based approaches could contribute to the identification of novel ASD and PANS biomarkers.

The Aetiology of Tourette Syndrome and Chronic Tic Disorder in Children and Adolescents: A Comprehensive Systematic Review of Case-Control Studies

(1) Introduction: Tourette syndrome (TS) and chronic tic disorder (CTD) are common neurodevelopmental/-psychiatric disorders. The aetiological factors that contribute to the pathogenesis of TS/CTD are still poorly understood. The possible risk factors for TS/CTD are considered to be a combination of genetic, immunological, psychological and environmental factors. A comprehensive systematic review was conducted to assess the association between aetiological factors and TS/CTD. (2) Methods: Electronic databases, including PubMed, Embase, Web of Science, Wanfang data, and CNKI, were searched to identify the etiological factors of children and adolescents (≤18 years) with TS/CTD based on a case-control study. Quality assessments were performed according to the Newcastle-Ottawa scale (NOS). (3) Results: According to sample sizes and NOS values, recent evidence may support that genetic factors (BTBD9 and AADAC), immunological factors (streptococcus and mycoplasma pneumoniae infections), environmental factors (conflict, history of perinatal diseases, and family history of neurological and psychiatric diseases and recurrent respiratory infections) and psychological factors (major life events) are associated with the pathogenesis of TS/CTD. (4) Conclusions: Some risk factors in different categories may be the etiological factors of TS/CTD, but there is a lack of studies on the interaction among the factors, which may require more attention in the future.

Big data analytics frameworks for the influence of gut microbiota on the development of tic disorder

The association between gut microbiota and psychiatric disorders has received increasing research attention. Meanwhile, big data analysis has been utilized in many filed including business, human healthcare analysis, etc. The primary objective of this article was to provide insights into Big Data Analytics (BDA) to clarify the association between gut microbiota and TD (Tic disorder). Specifically, we investigated the recent studies related to gut microbiota composition differences in patients with TD compared to health people. We searched on PubMed and Embase (Ovid) databases for relevant published articles until June 15, 2021. A total of 78 TD and 62 health control stool samples were examined. Case-control design was applied in all the studies. No consensus was evident in α-diversity and β-diversity. The abundance of phyla Bacteroidetes and Firmicutes was predominant at the taxa level. Gut microbiota taxonomic differences were found between TD cases and controls, though inconsistently across studies. Further studies are needed to reveal the underlying pathophysiology of TD and correlation between TD and gut microbiota composition.

Changes of Cytokines in Children With Tic Disorder

Tic disorder (TD) is a common childhood-onset disease associated with abnormal development of brain networks involved in the motor and sensory processing. The underlying pathophysiological mechanisms in TD are still unclear. An involvement of immune mechanisms in its pathophysiology has been proposed. This study investigates the association between the changes of cytokines and the etiology and development of TD. Different expressions of cytokines in a larger number of samples in our study may provide new insights to the field. The levels of cytokines (IL-2, IL-4, IL-6, IL-10, TNF-α, and IFN-γ) were evaluated in 1,724 patients who were clinically diagnosed with TD from 1 to 17.5 years old and 550 were from 6 months to 14.5 years old in the control group. We assessed the levels of cytokines according to the patient's medication status and the severity of the disease. Of the cytokines we investigated, the serum IL-6 concentration of children with TD was significantly higher than that of the control group, while the levels of other cytokines were lower in TD patients. In the patient group whose YTGSS score ranged from 1 to 9, the IL-4, IL-10, and IFN-γ levels increased in medication group compared to unmedication group. Our data suggested that the cytokines (IL-2, IL-4, IL-6, IL-10, TNF-α, and IFN-γ) may play an important role in the etiology and the severity in TD. Whether drug intervention in the early stage of tic disorder has a better effect on children needs further research.

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

Infectious pathogens may represent an environmental risk factor for chronic tic disorders (CTD). This cross-sectional study aimed to determine whether Mycoplasma pneumoniae (M. pneumoniae) IgG positivity is associated with the presence or severity of tics. We compared M. pneumoniae IgG positivity across three groups: children and adolescents (3-16 years) with CTD (CTD group; n = 302); siblings (3-10 years) of people with CTD who developed tics within a seven-year follow-up period (tic onset group; n = 51); siblings (4-10 years) who did not develop tics within the study period and were ≥10-years-old at their last assessment (unaffected group; n = 88). The relationship between M. pneumoniae IgG positivity and the presence and severity of tics was analysed using multilevel models controlling for site, family relatedness, sex, age, presence of comorbid obsessive-compulsive and/or attention-deficit/hyperactivity disorder and use of psychotropic medication. M. pneumoniae IgG positivity was not associated with the presence of CTD, or the first onset of tics as compared to siblings who remained unaffected. M. pneumoniae IgG positivity was associated with a higher tic severity score within the CTD group (β = 2.64, s.e. = 1.15, p = 0.02). 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.

The relationship between allergic diseases and tic disorders: A systematic review and meta-analysis

This systematic review aims to 1) explore the association between tic disorders (TD) and allergic diseases (AD), 2) judge whether patients with a diagnosis of TD are prone to suffer from a specific AD, by compiling the literature and analyzing the evidence. A literature search was conducted in PubMed and Embase database on February 24, 2021. The inclusion criteria for the literature were all comparative studies that reported TD patients were diagnosed with allergic illness as well. We identified that TD is positively associated with asthma, allergic rhinitis and allergic conjunctivitis, respectively. Especially, provisional tic disorder (PTD) patients might be more likely to suffer from these three AD, although it is still difficult to accurately predict which specific AD is prone to be accompanied by a specific TD. Shared genetic and etiological factors are suggested responsible for the AD-TD association. Large prospective cohort studies in future might shed light on a deep understanding of the relationship between immune disorders and tics.

Depicting the composition of gut microbiota in children with tic disorders: an exploratory study

BACKGROUND

Symptom improvement in children with tic disorder (TD) following fecal microbiota transplantation led us to investigate the gut microbiota in TD. This exploratory study aims to depict the gut microbial profile in patients with TD and explore the impact of dopamine receptor antagonist (DRA) drugs on the composition and metabolic function of the gut microbiota.

METHODS

The gut microbiota were profiled in fecal samples of 49 children with TD and 50 matched healthy controls (HC) using shotgun metagenomic sequencing. A random forest (RF) model was constructed using the gut bacterial species to distinguish TD from HC. Associations between clinical metadata and microbial abundance or function were analyzed using MaAsLin2 and Spearman correlation.

RESULTS

The gut microbiota in children with TD was featured by higher abundances of Bacteroides plebeius and Ruminococcus lactaris (a potential pro-inflammatory taxon) and lower abundances of Prevotella stercorea and Streptococcus lutetiensis compared to HC. The constructed RF model accurately distinguished TD from HC based on the gut microbiota profile, resulting in an AUC of 0.884. Significant correlations were observed between tic symptom severity and the abundances of multiple bacterial species and gut microbiota metabolic functions. Multivariate analysis identified an upregulation of 4-aminobutanoate (GABA) degradation in the gut microbiota associated with TD status. The gut microbiota of DRA-treated TD children showed a distinct gut microbiota compared to the treatment-naïve group, represented by an increase in some potential enteric pathogens such as Escherichia coli, a decline in several species including Akkermansia muciniphila, and alterations in various metabolic functions.

CONCLUSIONS

Bacterial species promoting inflammatory responses and those modulating neurotransmitters such as GABA may be involved in the pathogenesis of TD. The use of DRA drugs is likely to induce overgrowth of some enteric pathogens and alter the gut microbiota metabolism.

Immunity and Gilles de la Tourette syndrome: A systematic review and meta-analysis of evidence for immune implications in Tourette syndrome

BACKGROUND AND PURPOSE

The neurobiology of Gilles de la Tourette syndrome (GTS) is known to involve corticostriatal loops possibly under genetic control. Less is known about possible environmental triggers of GTS. Specifically, immune-related events following possible environmental inducers have been evoked, but important controversies still exist. In this systematic review and meta-analysis, we looked for evidence in favor of such possibilities.

METHODS

We performed a systematic review and meta-analysis of all immunological data in PubMed.

RESULTS

We found large discrepancies concerning immune dysfunctions in GTS, and meta-analyzing cytokines data did not allow us to conclude there is an involvement of specific cytokines in GTS neurobiology. When looking specifically at pediatric autoimmune neuropsychiatric disorder associated with streptococcus/pediatric acute onset neuropsychiatric syndrome, we found some important evidence of a possible infectious involvement but in a limited number of studies. Our meta-analysis found an increased level of anti-streptolysin O antibodies in GTS patients, but the level of anti-DNase B antibodies was not increased.

CONCLUSIONS

Too many questions still exist to allow us to definitively reach the conclusion that there is an infectious and immunological etiology in GTS. Much work is still needed to elucidate the possible role of immunology in GTS neurobiology and to favor immunological treatment rather than classical treatment.

Metabolomic Characterization of Pediatric Acute-Onset Neuropsychiatric Syndrome (PANS)

Introduction

PANS is a controversial clinical entity, consisting of a complex constellation of psychiatric symptoms, adventitious changes, and expression of various serological alterations, likely sustained by an autoimmune/inflammatory disease. Detection of novel biomarkers of PANS is highly desirable for both diagnostic and therapeutic management of affected patients. Analysis of metabolites has proven useful in detecting biomarkers for other neuroimmune-psychiatric diseases. Here, we utilize the metabolomics approach to determine whether it is possible to define a specific metabolic pattern in patients affected by PANS compared to healthy subjects.

Design

This observational case-control study tested consecutive patients referred for PANS between June 2019 to May 2020. A PANS diagnosis was confirmed according to the PANS working criteria (National Institute of Mental Health [NIMH], 2010). Healthy age and sex-matched subjects were recruited as controls.

Methods

Thirty-four outpatients referred for PANS (mean age 9.5 years; SD 2.9, 71% male) and 25 neurotypical subjects matched for age and gender, were subjected to metabolite analysis. Serum samples were obtained from each participant and were analyzed using Nuclear Magnetic Resonance (NMR) spectroscopy. Subsequently, multivariate and univariate statistical analyses and Receiver Operator Curves (ROC) were performed.

Results

Separation of the samples, in line with the presence of PANS diagnosis, was observed by applying a supervised model (R²X = 0.44, R²Y = 0.54, Q² = 0.44, p-value < 0.0001). The significantly altered variables were 2-Hydroxybutyrate, glycine, glutamine, histidine, tryptophan. Pathway analysis indicated that phenylalanine, tyrosine, and tryptophan metabolism, as well as glutamine and glutamate metabolism, exhibited the largest deviations from neurotypical controls.

Conclusion

We found a unique plasma metabolic profile in PANS patients, significantly differing from that of healthy children, that suggests the involvement of specific patterns of neurotransmission (tryptophan, glycine, histamine/histidine) as well as a more general state of neuroinflammation and oxidative stress (glutamine, 2-Hydroxybutyrate, and tryptophan-kynurenine pathway) in the disorder. This metabolomics study offers new insights into biological mechanisms underpinning the disorder and supports research of other potential biomarkers implicated in PANS.

Immunological Dysfunction in Tourette Syndrome and Related Disorders

Chronic tic disorder and Tourette syndrome are common childhood-onset neurological diseases. However, the pathophysiology underlying these disorders is unclear, and most studies have focused on the disinhibition of the corticostriatal–thalamocortical circuit. An autoimmune dysfunction has been proposed in the pathogenetic mechanism of Tourette syndrome and related neuropsychiatric disorders such as obsessive–compulsive disorder, autism, and attention-deficit/hyperactivity disorder. This is based on evidence from animal model studies and clinical findings. Herein, we review and give an update on the clinical characteristics, clinical evidence, and genetic studies in vitro as well as animal studies regarding immune dysfunction in Tourette syndrome.

An examination of the relationship between regulatory T cells and symptom flare-ups in children and adolescents diagnosed with chronic tic disorder and Tourette syndrome

BACKGROUND

Tourette syndrome (TS) is a childhood-onset neurodevelopmental disorder characterized by several motor and phonic tics.

AIMS

In this study, we aimed to compare activated regulatory T cell (Treg) values between patients with TS/chronic tic disorder (CTD) and age- and sex-matched healthy controls (HCs).

MATERIALS AND METHOD

Patients with TS/CTD and age- and sex-matched HCs were included in the study. The severity of the disease was evaluated using the Yale Global Tic Severity Scale. CD4⁺CD25⁺CD127^low Tregs from the patient group and the control group were compared using flow cytometry.

RESULTS

The study included 48 patients diagnosed with TS/CTD (36 males and 12 females, mean age: 11.58 ± 2.61) and 24 HCs (18 males and 6 females, mean age: 11.63 ± 2.60). The TS/CTD group had significantly higher activated regulatory T percentile with respect to the T helper value compared to the HCs (p = 0.010). Lymphocyte count, T lymphocyte count, T lymphocyte percentage, T-helper lymphocyte count, and T-helper lymphocyte percentage were lower in the patient group compared to the control group (p = 0.024, 0.003, 0.007, <0.001, <0.001, respectively). The comparison of three groups (mild, moderate-severe, and HCs) revealed that T lymphocyte number and percentage and the T helper number and percentage were significantly higher in the HC group compared to the moderate-severe group, whereas the activated Treg percentage with respect to the T helper value was significantly higher in the moderate-severe group compared to the HC group (0.002, 0.026, <0.001, <0.001, 0.027, respectively).

CONCLUSION

Our results suggest that Tregs may have a role in the pathogenesis of TS/CTD.

Alterations in the Nervous System and Gut Microbiota after β-Hemolytic Streptococcus Group A Infection-Characteristics and Diagnostic Criteria of PANDAS Recognition

The objective of this paper is to review and summarize conclusions from the available literature regarding Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal Infections (PANDAS). The authors have independently reviewed articles from 1977 onwards, primarily focusing on the etiopathology, symptoms, differentiation between similar psychiatric conditions, immunological reactions, alterations in the nervous system and gut microbiota, genetics, and the available treatment for PANDAS. Recent research indicates that PANDAS patients show noticeable alterations within the structures of the central nervous system, including caudate, putamen, globus pallidus, and striatum, as well as bilateral and lentiform nuclei. Likewise, the presence of autoantibodies that interact with basal ganglia was observed in PANDAS patients. Several studies also suggest a relationship between the presence of obsessive-compulsive disorders like PANDAS and alterations to the gut microbiota. Further, genetic predispositions-including variations in the MBL gene and TNF-α-seem to be relevant regarding PANDAS syndrome. Even though the literature is still scarce, the authors have attempted to provide a thorough insight into the PANDAS syndrome, bearing in mind the diagnostic difficulties of this condition.

Pediatric Acute-onset Neuropsychiatric Syndrome and Mycoplasma Pneumoniae Infection: A Case Report Analysis with a Metabolomics Approach

Pediatric Acute-onset Neuropsychiatric Syndrome (PANS) is a clinical condition characterized by a sudden and dramatic obsessive-compulsive disorder with a suggested post-infectious immune-mediated etiology. This condition is accompanied by an extensive series of relatively serious neuropsychiatric symptoms. The diagnosis of PANS is made by "exclusion", as the individual PANS symptoms overlap with a multiplicity of psychiatric disorders with the onset in childhood. A number of researchers accumulated evidence to support the hypothesis that PANS was closely associated with a number of infections. In the last decade, metabolomics played an essential role in improving the knowledge of complex biological systems and identifying potential new biomarkers as indicators of pathological progressions or pharmacologic responses to therapy. The metabolome is considered the most predictive phenotype, capable of recognizing epigenetic differences, reflecting more closely the clinical reality at any given moment and thus providing extremely dynamic data. In the present work, the most recent hypothesis and suggested mechanisms of this condition are reviewed and the case of a 10 - year-old girl with PANS is described, before and after clarithromycin treatment. The main results of this case report are discussed from a metabolomics point of view. The alteration of several metabolic pathways concerning the microbial activity highlights the possible role of the microbiome in the development of PANS. Furthermore, different metabolic perturbations at the level of protein biosynthesis, energy and amino acid metabolisms are observed and discussed. Based on our observations, it is believed that metabolomics is a promising technology to unravel the mysteries of PANS in the near future.

Psychiatric syndromes other than dementia

There is wide variability in how psychiatry guidelines and textbooks address the question of cerebrospinal fluid (CSF) diagnostics in the screening of psychiatric disorders. A United States-based textbook confirms that there is no consensus about which laboratory investigation should be routinely performed in psychiatric patients, but with respect to CSF diagnostics, the differences are even more striking. A survey among European experts showed a wide variety of opinions regarding clinical use and criteria in various countries of Europe and worldwide: some psychiatrists, mostly university hospital-based, recommended performing CSF diagnostics in every patient first experiencing severe mental illness (SMI), but especially in patients from the schizophrenia spectrum, whereas others almost never perform CSF examinations themselves and usually refer patients to neurology departments if necessary. Minor neurologic signs are generally frequent in SMI, mainly in affective and schizophrenic disorders. Even with neurologic signs present, there are no clear guidelines regarding CSF evaluation, leaving doctors with experience-based decision making. However, the field is evolving. A recent review provides helpful yellow and red flags for differential diagnosis of SMI from autoimmune encephalitis; interestingly, minor CSF abnormalities are considered a red flag, suggesting that CSF should be routinely performed in acute psychiatric patients. There are reports of single cases identified as an established neurologic disorder: patients within affective and schizophrenic spectrum disorders systematically underwent CSF examination, and were rediagnosed based on CSF results. This was often to the surprise of the psychiatric doctors. Overall, an increasing number of psychiatrists believe that CSF is too rarely examined in psychiatric patients. This chapter provides an overview of differential diagnostic issues in SMI, particularly for new-onset cases. The general recommendations regarding CSF examination procedures can be found in other chapters of this book. Here we focus on specific aspects of differential diagnosis in SMI. Also, there will be an overview of admittedly limited CSF research efforts in psychiatric disorders, focusing on more recent CSF studies. CSF studies in SMI performed with state-of-the-art methods, for example proteomics or assessments of cytokines, were intriguing but difficult to interpret and required critical considerations regarding respective methodology, an undertaking which is outside the scope of this chapter.

Clinical Management of Pediatric Acute-Onset Neuropsychiatric Syndrome: Part III-Treatment and Prevention of Infections

Objectives: Pediatric acute-onset neuropsychiatric syndrome (PANS) and its subset, pediatric autoimmune neuropsychiatric disorder associated with streptococcal infection (PANDAS), are emerging autoimmune encephalopathies of childhood. Management guidelines are needed. This article, from the PANS/PANDAS Consortium, presents a consensus management guideline for the infection components. Accompanying papers from the Consortium discuss psychiatric and immunomodulatory management. Methods: Literature was reviewed and integrated with the clinical experience of the authors to provide a set of practical guidelines. This article was submitted to all members of the PANS/PANDAS Consortium, and their additional comments were added. Results: The relationships between PANS and infections are reviewed. An approach to the retrospective diagnosis of group A streptococcal infection for an operational definition of PANDAS is proposed. An initial course of anti-streptococcal treatment is proposed for all newly diagnosed PANS cases. Chronic secondary antimicrobial prophylaxis is suggested for children with PANDAS who have severe neuropsychiatric symptoms or recurrent group A Streptococcus-associated exacerbations. Guidelines for children with non-streptococcal PANS include vigilance for streptococcal pharyngitis or dermatitis in the patient and close contacts. All patients with PANS or PANDAS should also be closely monitored for other intercurrent infections, including sinusitis and influenza. Intercurrent infections should be diagnosed and treated promptly according to current standard guidelines. A guideline for the assessment of infection at initial onset or during neuropsychiatric exacerbations is also presented. Standard immunizations and attention to vitamin D are encouraged. Data indicating limited utility of adenotonsillectomy and probiotics are presented. Conclusion: A working guideline for the management of infection issues in PANS and PANDAS, based on literature and expert opinion, is provided.

An expert opinion on PANDAS/PANS: highlights and controversies

OBJECTIVES

'Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal Infections' (PANDAS) identified a unique subgroup of patients with abrupt onset of obsessive compulsive disorder (OCD) symptoms clinically related to Streptococcus infection and accompanied by neuropsychological and motor symptoms. After almost 20 years, PANDAS has not been accepted as distinct disorder and new criteria for paediatric acute-onset neuropsychiatric syndrome (PANS) have been replaced it, highlighting the fact that several agents rather than only Streptococcus might be involved.

METHODS

Extensive review of the PANDAS/PANS literature was performed on PubMed.

RESULTS

Although antibiotics have been reported to be effective for acute and prophylactic phases in several uncontrolled studies and non-steroidal anti-inflammatory drugs (NSAID) are used during exacerbations, clinical multicenter trials are still missing. Selective serotonin reuptake inhibitors (SSRIs) and cognitive behavioural therapy (CBT) are still the first line of recommendation for acute onset OCD spectrum. Immunological therapies should be restricted to a few cases.

CONCLUSIONS

While PANDAS has found no confirmation as a distinct syndrome, and it is not presented in DSM-5, patients with acute onset OCD spectrum, neurocognitive and motor symptoms should be evaluated for inflammatory, infective, immunological and metabolic abnormalities with a comprehensive diagnostic algorithm.

Increased Risk of Tics in Children Infected with Enterovirus: A Nationwide Population-Based Study

OBJECTIVE

Both tics and enterovirus (EV) infections are common in children. The association between EV infections and tics has been seldom evaluated. The aim of this study was to evaluate the risk of diagnosed tics after EV infections in children.

METHODS

A nationwide retrospective cohort study was conducted to determine the risk of tics after EV infections by analyzing data from the National Health Insurance Research Database in Taiwan. Children aged < 18 years with EV infection during 2000 to 2007 were enrolled. For comparison, non-EV-infected children were randomly selected and matched with EV-infected children at a 1:1 ratio according to sex, age, urbanization level, parental occupation, and the year of EV infection. All patients were followed up until the diagnosis of tics, death, loss to follow-up, withdrawal from the insurance system, or December 31, 2008.

RESULTS

A total of 282,321 EV-infected and 282,317 non-EV-infected children were included in this study. The mean age was 2.39 years in both cohorts. The overall incidences of tics were 9.12 and 6.21 per 10,000 person-years in the EV-infected and non-EV-infected cohorts, respectively. Children with EV infection were significantly associated with an increased risk of tics compared with those without EV infection (adjusted hazard ratio, 1.38; 95% confidence interval, 1.27-1.5). Multivariable analyses showed that boys, children living in urbanized areas, children whose parents had white-collar jobs, and children with allergic rhinitis or bronchial asthma exhibited a significantly increased risk of tics.

CONCLUSION

This study revealed an increased risk of tics after EV infection in children.

Staphylococcus aureus Colonization Modulates Tic Expression and the Host Immune Response in a Girl with Tourette Syndrome

A 9-year-old girl with Tourette syndrome (TS) and increased antibody levels against Streptococcus pyogenes was monitored longitudinally for the presence of nasopharyngeal bacteria, specific antibody titers, and autoimmunity directed against brain antigens. Microbiological monitoring indicated that the child was an intermittent Staphylococcus aureus nasopharyngeal carrier. Clinical improvements in motor tic frequency and severity were observed during the S. aureus colonization phase and were temporally correlated with the downregulation of anti-streptococcal and anti-D1/D2 dopamine receptor antibody production. After decolonization, clinical conditions reverted to the poor scores previously observed, suggesting a possible role of the immune response in bacterial clearance as a trigger of symptom recrudescence. These findings imply that a cause-effect relationship exists between S. aureus colonization and tic improvement, as well as between bacterial decolonization and tic exacerbation. Understanding the impact of S. aureus on the host adaptive immune response and the function of autoantibodies in the pathogenesis of TS may alter approaches for managing autoimmune neuropsychiatric and tic disorders.

Characterization of the pediatric acute-onset neuropsychiatric syndrome phenotype

OBJECTIVE

Pediatric acute-onset neuropsychiatric syndrome (PANS) is a subtype of obsessive compulsive disorder (OCD) marked by an abrupt onset or exacerbation of neuropsychiatric symptoms. We aim to characterize the phenotypic presentation of youth with PANS.

METHODS

Forty-three youth (ages 4-14 years) meeting criteria for PANS were assessed using self-report and clinician-administered measures, medical record reviews, comprehensive clinical evaluation, and laboratory measures.

RESULTS

Youth with PANS presented with an early age of OCD onset (mean=7.84 years) and exhibited moderate to severe obsessive compulsive symptoms upon evaluation. All had comorbid anxiety and emotional lability, and scored well below normative means on all quality of life subscales. Youth with elevated streptococcal antibody titers trended toward having higher OCD severity, and presented more frequently with dilated pupils relative to youth without elevated titers. A cluster analysis of core PANS symptoms revealed three distinct symptom clusters that included core characteristic PANS symptoms, streptococcal-related symptoms, and cytokine-driven/physiological symptoms. Youth with PANS who had comorbid tics were more likely to exhibit a decline in school performance, visuomotor impairment, food restriction symptoms, and handwriting deterioration, and they reported lower quality of life relative to youth without tics.

CONCLUSIONS

The sudden, acute onset of neuropsychiatric symptoms, high frequency of comorbidities (i.e., anxiety, behavioral regression, depression, and suicidality), and poor quality of life capture the PANS subgroup as suddenly and severely impaired youth. Identifying clinical characteristics of youth with PANS will allow clinicians to diagnose and treat this subtype of OCD with a more strategized and effective approach.

Disordered eating and food restrictions in children with PANDAS/PANS

OBJECTIVE

Sudden onset clinically significant eating restrictions are a defining feature of the clinical presentation of some of the cases of pediatric acute-onset neuropsychiatric syndrome (PANS). Restrictions in food intake are typically fueled by contamination fears; fears of choking, vomiting, or swallowing; and/or sensory issues, such as texture, taste, or olfactory concerns. However, body image distortions may also be present. We investigate the clinical presentation of PANS disordered eating and compare it with that of other eating disorders.

METHODS

We describe 29 patients who met diagnostic criteria for PANS. Most also exhibited evidence that the symptoms might be sequelae of infections with Group A streptococcal bacteria (the pediatric autoimmune neuropsychiatric disorder associated with streptococcal infections [PANDAS] subgroup of PANS).

RESULTS

The clinical presentations are remarkable for a male predominance (2:1 M:F), young age of the affected children (mean=9 years; range 5-12 years), acuity of symptom onset, and comorbid neuropsychiatric symptoms.

CONCLUSIONS

The food refusal associated with PANS is compared with symptoms listed for the new Diagnostic and Statistical Manual of Mental Disorders, 5th ed. (DSM-V) diagnosis of avoidant/restrictive food intake disorder (ARFID). Treatment implications are discussed, as well as directions for further research.

Cefdinir for recent-onset pediatric neuropsychiatric disorders: a pilot randomized trial

OBJECTIVE

Previous studies suggest that the unexplained sudden and severe onset of obsessive-compulsive disorder (OCD) and/or tics may be infection or immune precipitated. Beta lactam antibiotics may be neuroprotective beyond their antimicrobial efficacy. We examine the preliminary safety and efficacy of cefdinir in reducing obsessive-compulsive and/or tic severity in children with new-onset symptoms.

METHOD

Twenty subjects were randomized to receive placebo or cefdinir for 30 days for the treatment of recent-onset OCD and/or tics. The placebo group received a comparable inactive treatment matched for taste, color, and consistency. The Children's Yale-Brown Obsessive-Compulsive Scale (CY-BOCS) and Yale Global Tic Severity Scale (YGTSS) were the primary outcome measures utilized.

RESULTS

Subjects receiving cefdinir saw notable improvements in tic symptoms, with 44.4% showing at least a 25% reduction in YGTSS (mean decrease=9.5) scores compared with 9.1% of the placebo group (mean decrease=0.13). Despite improvements, significant group differences were not observed for YGTSS (F [1, 13]=4.03, p=0.066) although there were moderate differences between group treatment effects (d=0.72). For OCD symptoms, subjects receiving cefdinir saw improvements in OCD symptoms, with 33.3% showing at least a 25% reduction in CY-BOCS scores (mean decrease=7.8) compared with 27.3% of the placebo group (mean decrease=4.7), but there were also no significant differences for CY-BOCS (F [1, 13]=0.385, p=0.546; d=0.24).

CONCLUSIONS

Subjects assigned to cefdinir exhibited notable, albeit nonstatistically significant, improvements in tic symptoms, compared with the placebo group. There were also some improvements in OCD symptoms, although these were not significant. Overall, cefdinir was well tolerated. Given these preliminary results, a fully powered study is warranted to explore the efficacy of cefdinir as a therapeutic tool for new-onset pediatric neuropsychiatric symptoms, particularly those that appear to be precipitated by infection.

Clinical evaluation of youth with pediatric acute-onset neuropsychiatric syndrome (PANS): recommendations from the 2013 PANS Consensus Conference

On May 23 and 24, 2013, the First PANS Consensus Conference was convened at Stanford University, calling together a geographically diverse group of clinicians and researchers from complementary fields of pediatrics: General and developmental pediatrics, infectious diseases, immunology, rheumatology, neurology, and child psychiatry. Participants were academicians with clinical and research interests in pediatric autoimmune neuropsychiatric disorder associated with streptococcus (PANDAS) in youth, and the larger category of pediatric acute-onset neuropsychiatric syndrome (PANS). The goals were to clarify the diagnostic boundaries of PANS, to develop systematic strategies for evaluation of suspected PANS cases, and to set forth the most urgently needed studies in this field. Presented here is a consensus statement proposing recommendations for the diagnostic evaluation of youth presenting with PANS.

Pediatric acute-onset neuropsychiatric syndrome

Whether some instances of obsessive-compulsive disorder are secondary to infectious and/or autoimmune processes is still under scientific debate. The nosology has undergone an iterative process of criteria and acronyms from PITANDS to PANDAS to PANS (or CANS for neurology). This review focuses on the clinical presentation, assessment, proposed pathophysiology, and treatment of pediatric autoimmune neuropsychiatric disorders associated with streptococcus (PANDAS), and the newest iteration, pediatric acute-onset neuropsychiatric syndrome (PANS). Children who have these symptoms, which have become known as PANS, have been described by their parents as "changed children."

Impaired activation of the innate immune response to bacterial challenge in Tourette syndrome

OBJECTIVES

Infections resulting in immune activation have been proposed to play an etiological role in a subgroup of patients with Tourette syndrome (TS).

METHODS

In order to further characterize the interaction between pathogens and the innate immune system the toll-like receptor (TLR) 4 on CD14 + monocytes and soluble CD14 (sCD14) levels were analyzed in the serum of 33 Tourette patients and 31 healthy controls. Moreover, collected blood samples were stimulated with lipopolysaccharide (LPS) mimicking a bacterial infection. TLR4 was analysed by flow cytometry, sCD14 was analysed by enzyme-linked immunosorbent assay.

RESULTS

Patients had a lower receptor expression of TLR4 after stimulation with LPS (P = 0.045) and higher levels of sCD14 (unstimulated P = 0.014, after LPS P = 0.045). The increase in TLR4 expression after stimulation with LPS was significantly higher in the control group (P = 0.041).

CONCLUSIONS

Higher levels of sCD14, lower levels of TLR4 expression after stimulation and a diminished up-regulation of TLR4 expression after LPS stimulation in patients might represent an impaired activation of the innate immune response in TS, especially in regard to bacterial infection. The impaired response to pathogens could eventually lead to a higher susceptibility for infections. Recurring infections and a chronic inflammation could trigger and maintain the symptoms of TS.

Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal Infections (PANDAS): An Evolving Concept

Pediatric autoimmune neuropsychiatric disorders associated with streptococcus infections (PANDAS) originated from the observational work of Swedo and collaborators, who formalized their definition in 1998 in a set of operational criteria. The application of these criteria, which focuses on tics and obsessive-compulsive symptoms as core symptoms, has encountered difficulties, eventually leading to a high rate of misdiagnosis. In particular, the core feature represented by the association between newly diagnosed infections and neuropsychiatric symptom relapses in youths with this diagnosis could not be demonstrated by longitudinal studies. Exploratory studies aiming to identify clinical or cognitive features that could discriminate PANDAS from other pediatric obsessive-compulsive and tic disorders present methodological limitations, and therefore are not conclusive. Other behavioral features, in addition to obsessive-compulsive symptoms and tics, have been included in pediatric acute-onset neuropsychiatric syndromes (PANS) and childhood acute neuropsychiatric syndromes (CANS), two new concepts recently proposed in order to define a much broader clinical spectrum encompassing etiologically diverse entities. Given the uncertainties on the clinical definition of PANDAS, it is not surprising that evidence in support of a post-infectious, immune-mediated pathophysiology is also insufficient. Anti-dopamine receptor antibodies might be relevant to both Sydenham's chorea (SC)-the prototypical post-streptococcal neuropsychiatric disorder-and some rare forms of encephalitis targeting the basal ganglia specifically, but studies exploring their association with children fulfilling Swedo's criteria for PANDAS have been inconclusive. Moreover, we lack evidence in favor of the efficacy of antibiotic prophylaxis or tonsillectomy in patients fulfilling Swedo's criteria for PANDAS, whereas a response to immune-mediated treatments like intravenous immunoglobulins has been documented by one study, but needs replication in larger trials. Overall, the available evidence does not convincingly support the concept that PANDAS are a well-defined, isolated clinical entity subdued by definite pathophysiological mechanisms; larger, prospective studies are necessary to reshape the nosography and disease mechanisms of post-streptococcal acute neuropsychiatric disorders other than SC. Research is also under way to shed further light on a possible relationship between streptococcal infections, other biological and psychosocial stressors, and the complex pathobiology of chronic tic disorders.

Neuroinflammation, neuroautoimmunity, and the co-morbidities of complex regional pain syndrome

Complex Regional Pain Syndrome (CRPS) is associated with non-dermatomal patterns of pain, unusual movement disorders, and somatovisceral dysfunctions. These symptoms are viewed by some neurologists and psychiatrists as being psychogenic in origin. Recent evidence, however, suggests that an autoimmune attack on self-antigens found in the peripheral and central nervous system may underlie a number of CRPS symptoms. From both animal and human studies, evidence is accumulating that neuroinflammation can spread, either anterograde or retrograde, via axonal projections in the CNS, thereby establishing neuroinflammatory tracks and secondary neuroinflammatory foci within the neuraxis. These findings suggest that neuroinflammatory lesions, as well as their associated functional consequences, should be evaluated during the differential diagnosis of non-dermatomal pain presentations, atypical movement disorders, as well as other "medically unexplained symptoms", which are often attributed to psychogenic illness.

Immune-mediated animal models of Tourette syndrome

An autoimmune diathesis has been proposed in Tourette syndrome (TS) and related neuropsychiatric disorders such as obsessive-compulsive disorder, attention-deficit/hyperactivity disorder, autism and anorexia nervosa. Environmental triggers including infection and xenobiotics are hypothesized to lead to the production of brain-directed autoantibodies in a subset of genetically susceptible individuals. Although much work has focused on Group A Streptococcus (GAS), the role of this common childhood infection remains controversial. Animal model studies based on immune and autoantibody findings in TS have demonstrated immunoglobulin (Ig) deposits and stereotypic movements and related behavioral disturbances reminiscent of TS following exposure to GAS, other activators of host anti-microbial responses, soluble immune mediators and anti-GAS or anti-neuronal antibodies. Demonstration of the ability to recreate these abnormalities through passive transfer of serum IgG from GAS-immunized mice into naïve mice and abrogation of this activity through depletion of IgG has provided compelling evidence in support of the autoimmune hypothesis. Immunologically-based animal models of TS are a potent tool for dissecting the pathogenesis of this serious neuropsychiatric syndrome.

The Relationship between Tourette's Syndrome and Infections

Increasing evidence shows that infections and an activated immune status might be involved in the pathogene-sis of tic disorders. Studies discuss the influence of neurotrophic bacteria and viruses on different psychiatric disorders. In addition, signs of inflammation and immunological abnormalities have been described especially in schizophrenia and Tourette’s syndrome (tic disorder). Neuroimaging studies revealed increased microglial activation in psychiatric diseases; indicating an inflammatory state of the CNS.

However, it still remains unclear what the underlying mechanism is of how infectious agents could contribute to tic symp-toms. One hypothesis is that not only one particular infectious agent causes directly to the disease; instead different (chronic) infections influence the immune balance and are therefore involved in the pathology. In tic disorders, infections with group A streptococci, Borrelia burgdorferi or Mycoplasma pneumoniae seem to be associated with symptoms of the disease. Studies have shown that immunologic treatment improves and prevents the re-occurrence of clinical symptoms in Tourette’s syndrome. Also post-infectious events by cross-reactive antibodies(against M-protein) and an altered dopamine rgic(noradrenergic) neurotransmission as well as inflammatory/immunological dysregulations were considered as possible mechanisms to cause symptoms. Another contributing factor to the pathogenesis of these diseases could be an activation of the tryptophan catabolism through infectious agents. Tryptophan functions as a precursor for neurotransmitters like se-rotonin and becomes degraded to products that can modulate the neurotransmitter balance.

A deeper insight into the precise mechanism of how infectious agents influence immune parameter, tryptophan metabo-lism and the resulting neurotransmitter availability could help finding new therapeutic strategies.

Infectious Agents are Associated with Psychiatric Diseases

There are several infectious agents in the environment that can cause persistent infections in the host. They usually cause their symptoms shortly after first infection and later persist as silent viruses and bacteria within the body. However, these chronic infections may play an important role in the pathogenesis of schizophrenia and Tourette’s syndrome (TS). We investigated the distribution of different neurotrophic infectious agents in TS, schizophrenia and controls. A total of 93 individuals were included (schizophrenic patients, Tourette patients and controls). We evaluated antibodies against cytomegalovirus (CMV), herpes-simplex virus (HSV), Epstein-Barr virus, Toxoplasma, Mycoplasma and Chlamydia trachomatis/pneumoniae. By comparing schizophrenia and TS, we found a higher prevalence of HSV (P=0.017) and CMV (P=0.017) antibodies in schizophrenic patients. Considering the relationship between schizophrenia, TS and healthy controls, we showed that there are associations for Chlamydia trachomatis (P=0.007), HSV (P=0.027) and CMV (P=0.029). When all measured viruses, bacteria and protozoa were combined, schizophrenic patients had a higher rate of antibodies to infectious agents than TS patients (P=0.049). Tourette and schizophrenic patients show a different vulnerability to infectious agents. Schizophrenic patients were found to have a higher susceptibility to viral infections than individuals with TS. This finding might point to a modification in special immune parameters in these diseases.

Therapie der Tic-Störungen

Seit dem Erscheinen unserer letzten Übersichtsarbeit zur «Therapie der Tic-Störungen» in der Zeitschrift für Kinder- und Jugendpsychiatrie wurden große Fortschritte auf diesem Gebiet erzielt. So wurden einzelne Bausteine auf dem Weg zur optimalen Behandlung konkretisiert, z. B. Veröffentlichung einheitlicher Kriterien zur Behandlungsindikation oder Entwicklung und Evaluierung eines detaillierten verhaltenstherapeutischen Manuals zum Habit-Reversal-Training. Daneben sind neue Therapiemöglichkeiten, wie das Medikament Aripiprazol oder die Tiefenhirnstimulation, erfolgreich implementiert worden. Auch wurde das Augenmerk viel stärker auf begleitende Störungen, wie ADHS und Zwangsstörungen, gerichtet, da diese in der Regel eine besonders starke Beeinträchtigung für die weitere Entwicklung des Kindes oder Jugendlichen darstellen. Dennoch bestehen weiterhin große Wissenslücken über die Effektivität der einzelnen Behandlungsmethoden, möglicher Kombinationsbehandlungen sowie deren direkter Vergleich untereinander. Daneben erschwert das Fehlen jeglicher Parameter zur Vorhersage der individuell sehr unterschiedlichen Entwicklung der Tics über die nächsten Monate und Jahre eine evidenzbasierte Therapieempfehlung und damit das Erlernen der Feinheiten bei der Behandlung von Tic-Störungen. Zusammengefasst ist noch immer eine große klinische Erfahrung für die Therapieentscheidungen beim einzelnen Patienten von großem Vorteil angesichts der enormen Bandbreite an individueller Tic-Symptomatik und Komorbidität gepaart mit den unvorhersehbaren Schwankungen im zeitlichen Verlauf.

Altered monocyte activation markers in Tourette's syndrome: a case-control study

BACKGROUND

Infections and immunological processes are likely to be involved in the pathogenesis of Tourette's syndrome (TS). To determine possible common underlying immunological mechanisms, we focused on innate immunity and studied markers of inflammation, monocytes, and monocyte-derived cytokines.

METHODS

In a cross-sectional study, we used current methods to determine the number of monocytes and levels of C-reactive protein (CRP) in 46 children, adolescents, and adult patients suffering from TS and in 43 healthy controls matched for age and sex. Tumor necrosis factor alpha (TNF-alpha), interleukin 6 (IL-6), soluble CD14 (sCD14), IL1-receptor antagonist (IL1-ra), and serum neopterin were detected by immunoassays.

RESULTS

We found that CRP and neopterin levels and the number of monocytes were significantly higher in TS patients than in healthy controls. Serum concentrations of TNF-alpha, sIL1-ra, and sCD14 were significantly lower in TS patients. All measured values were within normal ranges and often close to detection limits.

CONCLUSIONS

The present results point to a monocyte dysregulation in TS. This possible dysbalance in innate immunity could predispose to infections or autoimmune reactions.

Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal Infection (PANDAS): a Controversial Diagnosis

Despite more than a decade of studying pediatric autoimmune neuropsychiatric disorders associated with streptococcal infection (PANDAS), it is still not possible to confirm its existence and whether it is a poststreptococcal autoimmune disorder. Many controversies remain: the diagnostic criteria have not been validated, evidence of autoimmunity remains inconclusive, evidence of a genetic predisposition is weak, and streptococcal infections are common in childhood and could represent only a trigger of exacerbations of tics and obsessive-compulsive disorder. Patients who fit the PANDAS criteria appear to represent a subgroup of children with chronic tic disorder and/or obsessive-compulsive disorder who may experience symptom exacerbations after group A β-hemolytic streptococci infections; however, those infections are not the sole or even the most common antecedent of exacerbations. There is not enough evidence to support PANDAS as a unique clinical entity.

Altered immunoglobulin profiles in children with Tourette syndrome

BACKGROUND

Post-infectious autoimmunity and immune deficiency have been implicated in the pathogenesis of Tourette syndrome (TS). We asked here whether B cell immunity of patients with TS differs from healthy subjects.

METHODS

In two independent cross-sectional samples, we compared serum levels of IgG1, IgG2, IgG3, IgG4, IgM, IgA, and IgE in 21 patients with TS from Yale University (17 males, 4 females, 8-16 years) versus 21 healthy controls (13 males, 8 females, 7-17 years); and in 53 patients with TS from Groningen University (45 males, 8 females, 6-18 years) versus 53 healthy controls (22 males, 31 females, 6-18 years), respectively. We also investigated correlations between Ig concentrations and symptom severity. In 13 additional patients (9 males, 4 females, age range 9-14), we established Ig profiles at time points before, during, and after symptom exacerbations.

RESULTS

IgG3 levels were significantly lower in Yale patients compared to healthy children (medians 0.28 versus 0.49 mg/ml, p=.04), while levels of IgG2, IgG4, and IgM in patients were lower at trend-level significance (p≤.10). Decreased IgG3 (medians 0.45 versus 0.52 mg/ml; p=.05) and IgM (medians 0.30 versus 0.38 mg/ml; p=.04) levels were replicated in the Groningen patients. Ig levels did not correlate with symptom severity. There was a trend-level elevation of IgG1 during symptom exacerbations (p=.09).

CONCLUSION

These pilot data indicate that at least some patients with TS have decreased serum IgG3, and possibly also IgM levels, though only few subjects had fully expressed Ig immunodeficiency. Whether these changes are related to TS pathogenesis needs to be investigated.

Streptococcal upper respiratory tract infections and exacerbations of tic and obsessive-compulsive symptoms: a prospective longitudinal study

OBJECTIVE

The objective of this blinded, prospective, longitudinal study was to determine whether new group A β hemolytic streptococcal (GABHS) infections are temporally associated with exacerbations of tic or obsessive-compulsive (OC) symptoms in children who met published criteria for pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections (PANDAS). A group of children with Tourette syndrome and/or OC disorder without a PANDAS history served as the comparison (non-PANDAS) group.

METHOD

Consecutive clinical ratings of tic and OC symptom severity were obtained for 31 PANDAS subjects and 53 non-PANDAS subjects. Clinical symptoms and laboratory values (throat cultures and streptococcal antibody titers) were evaluated at regular intervals during a 25-month period. Additional testing occurred at the time of any tic or OC symptom exacerbation. New GABHS infections were established by throat swab cultures and/or recent significant rise in streptococcal antibodies. Laboratory personnel were blinded to case or control status, clinical (exacerbation or not) condition, and clinical evaluators were blinded to the laboratory results.

RESULTS

No group differences were observed in the number of clinical exacerbations or the number of newly diagnosed GABHS infections. On only six occasions of a total of 51 (12%), a newly diagnosed GABHS infection was followed, within 2 months, by an exacerbation of tic and/or OC symptoms. In every instance, this association occurred in the non-PANDAS group.

CONCLUSIONS

This study provides no evidence for a temporal association between GABHS infections and tic/OC symptom exacerbations in children who meet the published PANDAS diagnostic criteria.

Elevated expression of MCP-1, IL-2 and PTPR-N in basal ganglia of Tourette syndrome cases

BACKGROUND

Post-infectious autoimmunity has been implicated in pathogenesis of Tourette's syndrome (TS) but no evidence of inflammation in central nervous system has been reported yet. We evaluated the expression of genes encoding selected inflammatory factors in post-mortem specimen of adult TS patients: interferon-γ (a cytokine released from CD8 and Thelper 1 CD4 subset of T lymphocytes), interleukin-2 (IL-2, a growth factor derived from T lymphocytes), interleukin-1 β (a cytokine involved in initiation of inflammation), monocyte chemotactic factor -1 (MCP-1, a marker of chronic inflammation) and CD45 (pan-leukocytic marker). For validation purposes, we determined expression of three genes that were previously reported to be elevated in post-mortem specimen of other TS cases: protein tyrosine phosphatase receptor-N (PTPR-N), PTPR-U and recoverin.

METHODS

Total RNA was isolated from formalin fixed brain tissue sections of basal ganglia area from four patients with TS and four control subjects, and real-time reverse transcription-polymerase chain reaction analysis was employed to quantitatively evaluate gene expression of the selected genes.

RESULTS

Significantly increased expression of MCP-1, IL-2 and PTPR-N was observed in TS cases (6.5-fold, 2.3-fold and 16.1-fold increase, respectively, p<0.05).

CONCLUSIONS

Elevated expression of MCP-1 and IL-2 supports the possibility of chronic inflammatory processes in the basal ganglia. Replication of elevated expression of PTPR-N in TS specimen suggests that pathway(s) involving this molecule may be important in TS pathogenesis.

Association between intracellular infectious agents and Tourette's syndrome

The underlying pathophysiological mechanisms in Tourette's syndrome (TS) are still unclear. Increasing evidence supports the involvement of infections, possibly on the basis of an altered immune status. Not only streptococci but also other infectious agents may be involved. This study investigates the association between the neurotrophic agents Chlamydia, Toxoplasma and TS. 32 patients with TS and 30 healthy matched controls were included. For each individual, IgA/IgG antibody titers against Chlamydia trachomatis/pneumoniae and Toxoplasma gondii were evaluated and analyzed with Fisher's exact test. We found a significantly higher rate of TS patients with elevated antibody titers against Chlamydia trachomatis (P = 0.017) as compared to controls. A trend toward a higher prevalence in the Tourette's group was shown for Toxoplasma (P = 0.069). In conclusion, within the TS patients a higher rate of antibody titers could be demonstrated, pointing to a possible role of Chlamydia and Toxoplasma in the pathogenesis of tic disorders. Because none of these agents has been linked with TS to date, a hypothesis is that infections could contribute to TS by triggering an immune response. It still remains unclear whether tic symptoms are partly due to the infection or to changes in the immune balance caused by an infection.

Immunologic analysis and serum heavy metal levels in exacerbated Tourette syndrome

Tourette syndrome (TS) is a childhood-onset and relapsing disorder characterized by involuntary simple or complex tics and high co-morbidity with behavioral anomalies. Its pathophysiologic mechanisms remain unclarified. We investigated immunologic alternations and serum heavy metal levels in patients with TS to elucidate the unclarified mechanisms. Based on the Yale Global Tic Severity Scale, fifteen TS subjects (four females) aged 8-34 (mean: 15.4 +/- 6.7) in exacerbation with mean severity score 40.3 +/- 14.6 were enrolled in this study. The immunoglobulin levels were normal except for higher immunoglobulin E levels (in 10 patients) with atopy. In exacerbation, there were reverse CD4/CD8 (in two), higher percentages of natural killer cells (in five) and memory T cells (in eight), diminished lymphocyte activation CD69 marker (in three) and impaired NK cytotoxicity (in six) that showed a trend of lower inhibitory CD94 (NKG2A), activating NKp46, and perforin expression compared to those of patients with stable TS and healthy controls, but similar granzyme expression. Serum ASLO, mycoplasma antibody and the levels of heavy metals were not significantly different. All aforementioned immune alterations returned to the normal ranges except for the consistently higher memory T cells. Our study demonstrated that, in some patients with TS, consistently higher memory T cells and lower cytotoxicity in exacerbation status reflect immune alterations and underscore the potential for immunomodulation or immunosuppressive treatment.

Streptococcal upper respiratory tract infections and psychosocial stress predict future tic and obsessive-compulsive symptom severity in children and adolescents with Tourette syndrome and obsessive-compulsive disorder

BACKGROUND

One goal of this prospective longitudinal study was to identify new group A beta-hemolytic streptococcal infections (GABHS) in children and adolescents with Tourette syndrome (TS) and/or obsessive-compulsive disorder (OCD) compared with healthy control subjects. We then examined the power of GABHS infections and measures of psychosocial stress to predict future tic, obsessive-compulsive (OC), and depressive symptom severity.

METHODS

Consecutive ratings of tic, OC, and depressive symptom severity were obtained for 45 cases and 41 matched control subjects over a 2-year period. Clinical raters were blinded to the results of laboratory tests. Laboratory personnel were blinded to case or control status and clinical ratings. Structural equation modeling for unbalanced repeated measures was used to assess the sequence of new GABHS infections and psychosocial stress and their impact on future symptom severity.

RESULTS

Increases in tic and OC symptom severity did not occur after every new GABHS infection. However, the structural equation model found that these newly diagnosed infections were predictive of modest increases in future tic and OC symptom severity but did not predict future depressive symptom severity. In addition, the inclusion of new infections in the model greatly enhanced, by a factor of three, the power of psychosocial stress in predicting future tic and OC symptom severity.

CONCLUSIONS

Our data suggest that a minority of children with TS and early-onset OCD were sensitive to antecedent GABHS infections. These infections also enhanced the predictive power of current psychosocial stress on future tic and OC symptom severity.

Children with Tourette's syndrome may suffer immunoglobulin A dysgammaglobulinemia: preliminary report

BACKGROUND

Postinfectious autoimmunity has been implicated in Tourette's syndrome and obsessive-compulsive disorder (TS/OCD), whereas increased frequency of upper respiratory tract infections (URTI) in TS/OCD patients suggests immune deficiency. We hypothesized that antineuronal antibodies may be elevated in patients (reflecting autoimmune processes), and levels of total immunoglobulins (Igs) may be decreased (reflecting immune deficiency).

METHODS

We analyzed plasma of TS/OCD patients (n = 24) and healthy age- and sex-matched control subjects (n = 22) by enzyme-linked immunosorbent assay (ELISA) for the levels of total and specific IgG, IgM, and IgA against antigens previously identified in multiple sclerosis (myelin basic protein and myelin-associated glycoprotein) and Sydenham's chorea (ganglioside-GM1, lysoganglioside, and tubulin).

RESULTS

Total IgA was decreased in TS/OCD patients (median 115 mg/100 mL) compared with control subjects (141 mg/100 mL; p = .02). Specific IgA against all antigens, except tubulin were also decreased in the patients (MPB 0 vs. 13 [ELISA units [EU]; myelin-associated glycoprotein 29 vs. 44 EU, p = .04; ganglioside GM1 21 vs. 35 EU, p = .01; lysoganglioside 44 vs. 56 EU, p = .03; tubulin 44 vs. 44 EU, p = .8). The levels of total IgA and anti-myelin basic protein (MBP) IgA were significantly lower in the subgroup of pediatric autoimmune neuropsychiatric disorder associated with Streptococcus (PANDAS) cases (n = 10) than in non-PANDAS cases (n = 9; total IgA 98 mg/100 mL vs. 133 mg/mL, p = .03; anti-MBP IgA 1 vs. 6 EU, p = .03) or healthy control subjects (total IgA 141 mg/100 mL, p = .02; anti-MBP IgA 13 EU, p = .005).

CONCLUSIONS

At least some TS/OCD patients may suffer IgA dysgammaglobulinemia, possibly rendering the children more prone to URTI.

Immunopathogenic mechanisms in tourette syndrome: A critical review

Tourette syndrome (TS) has a multifactorial etiology, in which genetic, environmental, immunological and hormonal factors interact to establish vulnerability. This review: (i) summarizes research exploring the exposure of TS patients to immune-activating environmental factors, and (ii) focuses on recent findings supporting a role of the innate and adaptive immune systems in the pathogenesis of TS and related disorders. A higher exposure prior to disease onset to group A beta-haemolytic streptococcal (GABHS) infections in children with tics and obsessive-compulsive (OC) symptoms has been documented, although their influence upon the course of disease remains uncertain. Increased activation of immune responses in TS is suggested by changes in gene expression profiles of peripheral immune cells, relative frequency of lymphocyte subpopulations, and synthesis of immune effector molecules. Increased activity of cell-mediated mechanisms is suggested by the increased expression of genes controlling natural killer and cytotoxic T cells, increased plasma levels of some pro-inflammatory cytokines which correlate with disease severity, and increased synthesis of antineuronal antibodies. Important methodological differences might account for some inconsistency among results of studies addressing autoantibodies in TS. Finally, a general predisposition to autoimmune responses in TS patients is indicated by the reduced frequency of regulatory T cells, which induce tolerance towards self-antigens. Although the pathogenic role of immune activation in TS has not been definitively proven, a pathophysiological model is proposed to explain the possible effect of immunity upon dopamine transmission regulation and the generation of tics.

Symptom dimensions and subtypes of obsessive-compulsive disorder: a developmental perspective

In the absence of definitive etiological markers for obsessive-compulsive disorder (OCD% obsessive-compulsive (OC) symptom dimensions may offer a fruitful point of orientation. These dimensions can be understood as defining potentially overlapping clinical features that may be continuous with "normal" worries first evident in childhood. Although the understanding of the dimensional structure of OC symptoms is still imperfect, a recent large-scale meta-analysis has confirmed the presence of at least four separa ble symptom dimensions in children, as well as adults, with OCD. A dimensional approach does not exclude other methods to parse OCD. Thus far, a pediatric age of onset, the presence of other family members with OCD, and the individual's "tic-related" status appear to be potentially useful categorical distinctions. Although the OC symptom dimensions appear to be valid for all ages, it is unlikely that the underlying genetic vulnerability factors and neurobiological substrates for each of these symptom dimensions are the same across the course of development.

Cold agglutinins in HIV-seropositive participants and diagnosis of respiratory disease due to Mycoplasma pneumoniae

OBJECTIVES

Cold agglutinin (CA) titers are one among the first pathological indicators for diagnosing Mycoplasma pneumoniae disease. We prospectively studied the prevalence of CAs in 300 HIV-positive and 75 HIV-negative individuals with respiratory disease in Chennai, India.

METHODS

The cold agglutination test was used and retrospectively compared with the results of a particle agglutination test.

RESULTS

While CAs were positive in 51 HIV cases, particle agglutination test detected anti-M pneumoniae antibodies from 43 cases with HIV disease (P = .001). The seroprevalence of CAs was 2.6% (n = 2) among HIV-negative participants. The mean CD4 count in CApositive and -negative HIV cases was 107.4 + 121.2 and 259.2 + 247.2 cells/microL (P = .001), respectively.

CONCLUSION

Our report suggests a basis for the existence of CAs in HIV-positive cases. Definitive diagnosis may be done only when CA detection is used in conjunction with a specific test.

Therapy-refractory Tourette syndrome: beneficial outcome with globus pallidus internus deep brain stimulation

We report on a female patient with Tourette syndrome and a 12-month follow-up after chronic deep brain stimulation in the globus pallidus internus which resulted in excellent remission of motor and vocal tics.

Age-related gene expression in Tourette syndrome

Because infection and immune responses have been implicated in the pathogenesis of Tourette syndrome (TS), we hypothesized that children with TS would have altered gene expression in blood compared to controls. In addition, because TS symptoms in childhood vary with age, we tested whether gene expression changes that occur with age in TS differ from normal control children. Whole blood was obtained from 30 children and adolescents with TS and 28 healthy children and adolescents matched for age, race, and gender. Gene expression (RNA) was assessed using whole genome Affymetrix microarrays. Age was analyzed as a continuous covariate and also stratified into three groups: 5-9 (common age for tic onset), 10-12 (when tics often peak), and 13-16 (tics may begin to wane). No global differences were found between TS and controls. However, expression of many genes and multiple pathways differed between TS and controls within each age group (5-9, 10-12, and 13-16), including genes involved in the immune-synapse, and proteasome- and ubiquitin-mediated proteolysis pathways. Notably, across age strata, expression of interferon response, viral processing, natural killer and cytotoxic T-lymphocyte cell genes differed. Our findings suggest age-related interferon, immune and protein degradation gene expression differences between TS and controls.