A Double-Blind Randomized Placebo-Controlled Pilot Study of Azithromycin in Youth with Acute-Onset Obsessive-Compulsive Disorder

An updated review of pediatric autoimmune neuropsychiatric disorders associated with Streptococcus/pediatric acute-onset neuropsychiatric syndrome, also known as idiopathic autoimmune encephalitis: What the allergist should know

BACKGROUND

Pediatric acute-onset neuropsychiatric syndrome, further subcategorized as pediatric autoimmune neuropsychiatric disorders associated with streptococcus, is a form of idiopathic autoimmune encephalitis (IAE). Poststreptococcal autoimmunity seen in Idiopathic autoimmune encephalitis manifests as various neuropsychiatric symptoms such as obsessive rituals, tics, anxiety, depression, and many others. Idiopathic autoimmune encephalitis has clinically heterogeneous phenotypes that make accurate diagnosing difficult, although diagnostic testing such as the Cunningham Panel increases the likelihood of finding effective treatments. Current recommended treatments include psychiatric medication, behavioral intervention, antibiotics, anti-inflammatory therapy, and immunomodulating therapy.

OBJECTIVE

To provide an updated review on the diagnosis, management, and treatment of pediatric autoimmune neuropsychiatric disorder associated with streptococcus and pediatric autoimmune neuropsychiatric syndrome, also referred to as IAE.

RESULTS

Information from 47 sources was used to outline current knowledge of IAE pathophysiology, clinical manifestations, and epidemiology, and to outline diagnostic recommendations and current treatment guidelines. Gaps in knowledge, in addition to current controversy, were also outlined to provide a thorough background of this condition and future needs for IAE research.

CONCLUSION

Owing to the complexity and variability in ways patients with IAE may present to the allergist/immunologist office, an interdisciplinary approach is imperative to provide patients with the best medical care. Still, more research is needed to further elucidate the mechanism(s) and optimal treatment algorithm for IAE to facilitate broader recognition and acceptance of this condition by the medical community.

Pediatric Acute-Onset Neuropsychiatric Syndrome: Current Perspectives

Pediatric acute-onset neuropsychiatric syndrome (PANS) features a heterogeneous constellation of acute obsessive-compulsive disorder (OCD), eating restriction, cognitive, behavioral and/or affective symptoms, often followed by a chronic course with cognitive deterioration. An immune-mediated etiology is advocated in which the CNS is hit by different pathogen-driven (auto)immune responses. This narrative review focused on recent clinical (ie, diagnostic criteria, pre-existing neurodevelopmental disorders, neuroimaging) and pathophysiological (ie, CSF, serum, genetic and autoimmune findings) aspects of PANS. We also summarized recent points to facilitate practitioners with the disease management. Relevant literature was obtained from PubMed database which included only English-written, full-text clinical studies, case reports, and reviews. Among a total of 1005 articles, 205 were pertinent to study inclusion. Expert opinions are converging on PANS as the effect of post-infectious events or stressors leading to "brain inflammation", as it is well-established for anti-neuronal psychosis. Interestingly, differentiating PANS from either autoimmune encephalitides and Sydenham's chorea or from alleged "pure" psychiatric disorders (OCD, tics, Tourette's syndrome), reveals several overlaps and more analogies than differences. Our review highlights the need for a comprehensive algorithm to help both patients during their acute distressing phase and physicians during their treatment decision. A full agreement on the hierarchy of each therapeutical intervention is missing owing to the limited number of randomized controlled trials. The current approach to PANS treatment emphasizes immunomodulation/anti-inflammatory treatments in association with both psychotropic and cognitive-behavioral therapies, while antibiotics are suggested when an active bacterial infection is established. A dimensional view, taking into account the multifactorial origin of psychiatric disorders, should suggest neuro-inflammation as a possible shared substrate of different psychiatric phenotypes. Hence, PANS and PANS-related disorders should be considered as a conceptual framework describing the etiological and phenotypical complexity of many psychiatric disorders.

Neuroinflammation in Obsessive-Compulsive Disorder: Sydenham Chorea, Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal Infections, and Pediatric Acute Onset Neuropsychiatric Syndrome

Sydenham chorea (SC), pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections (PANDAS) and pediatric acute-onset neuropsychiatric syndrome (PANS) are postinfectious neuroinflammatory diseases that involve the basal ganglia and have obsessive-compulsive disorder as a major manifestation. As is true for many childhood rheumatological diseases and neuroinflammatory diseases, SC, PANDAS and PANS lack clinically available, rigorous diagnostic biomarkers and randomized clinical trials. Research on the treatment of these disorders depend on three complementary modes of intervention including: treating the symptoms, treating the source of inflammation, and treating disturbances of the immune system. Future studies should aim to integrate neuroimaging, inflammation, immunogenetic, and clinical data (noting the stage in the clinical course) to increase our understanding and treatment of SC, PANDAS, PANS, and all other postinfectious/immune-mediated behavioral disorders.

Pediatric Autoimmune Neuropsychiatric Disorders Associated With Group A Streptococci: Etiopathology and Diagnostic Challenges

Pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections (PANDAS) have attracted a lot of interest and discussion since it was originally characterized in 1998. The role of streptococcal infection in children with abrupt-onset obsessive-compulsive disorder (OCD) and new-onset tics, the natural history of this entity, and the role of symptomatic and disease-modifying therapies, such as antibiotics, immunotherapy, and psychoactive drugs, are still unresolved issues. Alternative therapies for acute-onset OCD have been developed based on this postulated pathophysiology, including antibiotics and immunomodulatory therapy. The literature on PANDAS therapy is varied but there is no clinical consensus on the treatment of choice.

While there is no convincing evidence for the autoimmune rationale for PANDAS, given the increased attention to this entity and the apparent growth in usage of this diagnostic category, it is critical to address concerns about the condition's diagnosis, treatment, and pathogenesis.

We conducted a multi-language literature search on Medline, Cochrane, Embase, and Google Scholar for a period spanning until October 2021. The following search strings and Medical Subject Heading (MeSH) terms were used: “PANDAS,” “Group A Streptococcus,” “OCD,” and “tics.” We explored the literature on PANDAS in terms of its epidemiology, pathophysiology, the role of group A streptococcal infection, associated complications, and prophylactic and treatment modalities.

We examined current working definitions of PANDAS, analyzed differential diagnoses, and published pieces of evidence for therapies associated with this entity, with a view to proposing a therapeutic strategy for children with acute symptoms that meet PANDAS criteria, in this review article.

Pediatric neuropsychiatric syndromes associated with infection and microbiome alterations: clinical findings, possible role of the mucosal epithelium, and strategies for the development of new animal models

INTRODUCTION

: Subsets of pediatric obsessive-compulsive disorder (OCD) and autism spectrum disorder (ASD) respectively have been associated with respiratory tract infections and alterations in the intestinal microbiome. Pediatric Acute-onset Neuropsychiatric Syndromes (PANS) refers to the sudden onset of neuropsychiatric symptoms that are triggered by several different infectious and non-infectious factors. Clinical studies and animal modeling are consistent with the proposal that inflammation plays an important etiological role in PANS, as well as in ASD associated with gut dysbiosis.

AREAS COVERED

The authors provide an overview of clinical studies of PANS and ASD associated with gastrointestinal symptoms, as well as the current strategies for studying these syndromes in rodent models. Finally, the authors highlight similarities between these syndromes that may provide clues to common etiological mechanisms.

EXPERT OPINION

Although data from existing animal models are consistent with an important role for anti-neuronal antibodies in PANS triggered by GAS infection, we lack models for identifying pathophysiological mechanisms of PANS associated with other infectious and non-infectious triggers. The authors propose a strategy for developing such models that incorporates known vulnerability and triggering factors for PANS into the modeling process. This novel strategy should expand our understanding of the pathophysiology of PANS, as well as facilitate the development of new pharmacological treatments for PANS and related syndromes.

Cognitive, Graphomotor, and Psychosocial Challenges in Pediatric Autoimmune Neuropsychiatric Disorders Associated With Streptococcal Infections (PANDAS)

OBJECTIVES

Pediatric autoimmune neuropsychiatric disorders associated with streptococcal infection (PANDAS) is characterized by the sudden onset of obsessive-compulsive disorder (OCD) and other neurobehavioral symptoms following group A streptococcal infection. The cardinal neuropsychiatric symptoms are believed to reflect an aberrant autoimmune or inflammatory response that may selectively disrupt basal ganglia function. The investigators examined whether neuropsychological skills associated with frontostriatal networks (executive functions and motor skills) are affected in patients with PANDAS following resolution of acute symptoms and the degree to which there are persistent social, emotional, and academic difficulties.

METHODS

Twenty-seven patients ages 6-14 years (mean age=9.63 years [SD=1.78]; male, N=22) completed neuropsychological testing as part of routine clinical care. Performances on measures of intellectual ability, executive function, motor skills, and academic skills are reported, as well as parent-reported emotional, behavioral, and social skills.

RESULTS

On neuropsychological measures, patients exhibited average intellectual functioning with relative and mild difficulties in skills supporting cognitive efficiency, including attentional regulation, inhibitory control, and processing speed. Dexterity was normal but graphomotor skills were reduced. Core reading, math, and writing skills were within expectations, but reading and math fluency were reduced, and the majority of patients received special education services or accommodations. Parents reported high levels of concern about anxiety, depression, inattention, hyperactivity, and social skills.

CONCLUSIONS

These findings indicated relative difficulties with aspects of executive and motor functions. Although evaluations were performed following the resolution of acute symptoms, ongoing and significant academic difficulties and emotional, behavioral, and social concerns were targets for clinical intervention and support.

Effects of azithromycin on ventricular repolarization in children with COVID-19

Introduction

Azithromycin is used to treat pediatric COVID-19 patients. It can also prolong the QT interval in adults. This study assessed the effects of azithromycin on ventricular repolarization in children with COVID-19.

Method

The study prospectively enrolled children with COVID-19 who received azithromycin between July and August 2020. An electrocardiogram was performed before, one, three, and five days post-treatment. Using ImageJ®, the following parameters were measured: QT max, QT min, Tp-e max, and Tp-e min. The parameters QTc max, QTc min, Tp-ec max, Tp-ec min, QTcd, Tp-ecd, and the QTc/Tp-ec ratio were calculated using Bazett's formula.

Results

The study included 105 pediatric patients (mean age 9.8±5.3 years). The pretreatment heart rate was higher than after treatment (before 92 [79–108]/min vs. Day 1 82 [69–108)]/min vs. Day 3 80 [68–92.2]/min vs. Day 5 81 [70–92]/min; p=0.05).

Conclusion

Azithromycin does not affect the ventricular repolarization parameters on ECG in pediatric COVID-19 cases.

Obsessive-Compulsive Disorder in PANS/PANDAS in Children: In Search of a Qualified Treatment-A Systematic Review and Metanalysis

Background: Several treatment options have been proposed for pediatric acute-onset neuropsychiatric syndrome/pediatric autoimmune neuropsychiatric disorder associated with streptococcal infection (PANS/PANDAS). Still, no clear therapeutic protocol has been recognized to prevent these neuropsychiatric diseases. The study aims to report on the literature evidence and different treatment strategies related to these disorders. Methods: We analyzed the last 20 years’ English language literature and performed a comprehensive review of the PANS/PANDAS treatment, including studies reporting OCD outcomes post-treatment follow-up. Results: We covered 11 articles in our systematic literature review for a total of 473 patients, of which four studies included 129 surgical subjects and seven papers with 326 medically treated patients. Pooled outcomes analysis, surgical and medical treatment reported an OCD reduction, but no statistical significance was obtained (p < 0.05 for both). Conclusions: Surgical therapy in selected patients can lead to promising results, although further evidence is needed. On the other hand, the role of medical therapy remains controversial, often due to the lack of univocal curative protocols and variable responses depending on the drug used and the timing of administration. Therefore, further investigations are necessary to clarify the most appropriate therapeutic procedure.

Immunological causes of obsessive-compulsive disorder: is it time for the concept of an "autoimmune OCD" subtype?

Obsessive-compulsive disorder (OCD) is a highly disabling mental illness that can be divided into frequent primary and rarer organic secondary forms. Its association with secondary autoimmune triggers was introduced through the discovery of Pediatric Autoimmune Neuropsychiatric Disorder Associated with Streptococcal infection (PANDAS) and Pediatric Acute onset Neuropsychiatric Syndrome (PANS). Autoimmune encephalitis and systemic autoimmune diseases or other autoimmune brain diseases, such as multiple sclerosis, have also been reported to sometimes present with obsessive-compulsive symptoms (OCS). Subgroups of patients with OCD show elevated proinflammatory cytokines and autoantibodies against targets that include the basal ganglia. In this conceptual review paper, the clinical manifestations, pathophysiological considerations, diagnostic investigations, and treatment approaches of immune-related secondary OCD are summarized. The novel concept of "autoimmune OCD" is proposed for a small subgroup of OCD patients, and clinical signs based on the PANDAS/PANS criteria and from recent experience with autoimmune encephalitis and autoimmune psychosis are suggested. Red flag signs for "autoimmune OCD" could include (sub)acute onset, unusual age of onset, atypical presentation of OCS with neuropsychiatric features (e.g., disproportionate cognitive deficits) or accompanying neurological symptoms (e.g., movement disorders), autonomic dysfunction, treatment resistance, associations of symptom onset with infections such as group A streptococcus, comorbid autoimmune diseases or malignancies. Clinical investigations may also reveal alterations such as increased levels of anti-basal ganglia or dopamine receptor antibodies or inflammatory changes in the basal ganglia in neuroimaging. Based on these red flag signs, the criteria for a possible, probable, and definite autoimmune OCD subtype are proposed.

Clinical guidance for diagnosis and management of suspected Pediatric Acute-onset Neuropsychiatric Syndrome in the Nordic countries

Pediatric acute-onset neuropsychiatric syndrome is a clinical concept used to describe a subgroup of children with sudden onset of psychiatric and somatic symptoms. The diagnostic term and especially management of children differs depending on the clinical setting to which they present, and the diagnosis and management is controversial. The aim of this paper is to propose a clinical guidance including homogenous diagnostic work-up and management of paediatric acute onset neuropsychiatric syndrome within the Nordic countries. The guidance is authored by a Nordic-UK working group consisting of paediatric neurologist, child psychiatrists and psychologists from Denmark, Norway, Sweden and Great Britain, and is the result of broad consensus. CONCLUSION: Consensus was achieved in the collaboration on work-up and treatment of patients with paediatric acute-onset neuropsychiatric syndrome, which we hope will improve and homogenise patient care and enable future collaborative research in the field.

Anti-inflammatory, antibacterial and immunomodulatory treatment in children with symptoms corresponding to the research condition PANS (Pediatric Acute-onset Neuropsychiatric Syndrome): A systematic review

OBJECTIVE

To assess effects of treatment against a hypothesized neuroinflammation in children with symptoms corresponding to the research condition Pediatric Acute-onset Neuropsychiatric Syndrome (PANS) which is not included in current diagnostic systems.

METHODS

Systematic literature searches were performed (1998 to June 2020) in PubMed, Embase, the Cochrane Library, CINAHL, PsycInfo, and HTA databases. Inclusion criteria: patients (P) were children (<18 years) with PANS; intervention (I)/comparison (C) was use of, versus no use of, anti-inflammatory, antibacterial or immunomodulating treatments; outcomes (O) were health-related quality of life (HRQL), level of functioning, symptom change, and complications.

RESULTS

Four randomised controlled trials (RCTs) and three non-RCTs, including 23 to 98 patients, fulfilled the PICO. HRQL was not investigated in any study. Regarding level of functioning, two RCTs investigated antibiotics (penicillin V, azithromycin) and one RCT investigated immunomodulating treatments (intravenous immunoglobulins (IVIG), plasma exchange). Regarding symptoms, two non-RCTs investigated anti-inflammatory treatment (cyclooxygenase (COX) inhibitors, corticosteroids), two RCTs and one non-RCT investigated antibiotics (penicillin V, azithromycin), and two RCTs investigated immunomodulating treatments (IVIG, plasma exchange). Complications, reported in five studies, were consistent with those listed in the summary of products characteristics (SPC). All studies were assessed to have some or major problems regarding directness, the absence of an established diagnosis contributing to clinical diversity in the studied populations. All studies were assessed to have major risk of bias, including selection and detection biases. Due to clinical and methodological diversity, meta-analyses were not performed.

CONCLUSION

This systematic review reveals very low certainty of evidence of beneficial effects, and moderate certainty of evidence of adverse effects, of anti-inflammatory, antibacterial or immunomodulating treatments in patients with symptoms corresponding to the research condition PANS. Available evidence neither supports nor excludes potential beneficial effects, but supports that such treatment can result in adverse effects.

REGISTRATION

PROSPERO (CRD42020155714).

Developmental Considerations in Obsessive Compulsive Disorder: Comparing Pediatric and Adult-Onset Cases

There appear to be two peaks of incidence of Obsessive Compulsive Disorder (OCD), one with a pre-adolescent onset and another in early adulthood. As new cases are added, the cumulative prevalence of OCD increases, but the great majority of cases have an onset in youth. The notion that early onset OCD represents a unique developmental subtype of the disorder has been considered by many researchers based on several specific age-related factors. Ascertainment and early intervention in affected youth is critical to abbreviate the functional impairments associated with untreated illness. In this paper we review the clinical, familial and translational biomarker correlates seen in early onset OCD that support the notion of a developmental subtype and discuss implications for research and treatment aimed at this cohort. The importance of cognitive, academic and social development tasks of childhood and adolescence, illness-specific and familial factors, and immune-mediated inflammatory factors are discussed, with their implications for management.

Diagnostic Approach to Pediatric Autoimmune Neuropsychiatric Disorders Associated With Streptococcal Infections (PANDAS): A Narrative Review of Literature Data

Pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections (PANDAS) are clinical conditions characterized by the sudden onset of obsessive-compulsive disorder and/or tics, often accompanied by other behavioral symptoms in a group of children with streptococcal infection. PANDAS-related disorders, including pediatric acute-onset neuropsychiatric syndrome (PANS), childhood acute neuropsychiatric symptoms (CANS), and pediatric infection triggered autoimmune neuropsychiatric disorders (PITANDs), have also been described. Since first defined in 1998, PANDAS has been considered a controversial diagnosis. A comprehensive review of the literature was performed on PubMed and Scopus databases, searching for diagnostic criteria and diagnostic procedures of PANDAS and related disorders. We propose a test panel to support clinicians in the workout of PANDAS/PANS patients establishing an appropriate treatment. However, further studies are needed to improve our knowledge on these acute-onset neuropsychiatric conditions.

Safety of azithromycin in pediatrics: a systematic review and meta-analysis

Purpose

To evaluate the toxicity of azithromycin in neonates, infants, and children.

Methods

A systematic review was performed for relevant studies using Medline (Ovid), PubMed, Cochrane Central Register of Controlled Trials, EMBASE, CINAHL, and International Pharmaceutical Abstracts. We calculated the pooled incidence of adverse drug reactions (ADRs) associated with azithromycin based on prospective studies (RCTs and prospective cohort studies) and analyzed the risk difference (RD) of ADRs between azithromycin and placebo or other antibiotics using meta-analysis of RCTs.

Results

We included 133 studies with 4243 ADRs reported in 197,675 neonates, infants, and children who received azithromycin. The safety of azithromycin as MDA in pediatrics was poorly monitored. The main ADRs were diarrhea and vomiting. In prospective non-MDA studies, the most common toxicity was gastrointestinal ADRs (938/1967; 47.7%). The most serious toxicities were cardiac (prolonged QT or irregular heart beat) and idiopathic hypertrophic pyloric stenosis (IHPS). Compared with placebo, azithromycin did not show increased risk ADRs based on RCTs (risk difference − 0.17 to 0.07). The incidence of QT prolonged was higher in the medium-dosage group (10–30 mg/kg/day) than that of low-dosage group (≤ 10 mg/kg/day) (82.0% vs 1.2%).

Conclusion

The safety of azithromycin as MDA needs further evaluation. The most common ADRs are diarrhea and vomiting. The risk of the most serious uncommon ADRs (cardiac-prolonged QT and IHPS) is unknown.

Electronic supplementary material

The online version of this article (10.1007/s00228-020-02956-3) contains supplementary material, which is available to authorized users.

Ethnicity moderates outcome in family focused treatment for pediatric obsessive compulsive disorder

OBJECTIVE

This study examined predictors and moderators of treatment outcome in a randomized controlled trial (RCT) comparing two active interventions for pediatric obsessive compulsive disorder that differed with respect to the focus and format of family intervention. We had a particular interest in the role of race/ethnicity in shaping outcomes given our relatively diverse sample composition and the limited prior work in this area.

METHOD

A total of 62 youths (Mean age = 12.71 years; 57 % male; 34 % non-white) were assigned to either a standard cognitive behavioral therapy (CBT) family intervention (ST) or to a tailored intervention designed for cases of OCD complicated by poor family functioning (Enhanced Family Therapy; ET). Treatment in both arms involved 12 sessions of exposure therapy; the family interventions differed. Predictor and moderator variables were chosen based on the extant literature.

RESULTS

Minority status did not predict outcome, suggesting that overall, white and non-white youth had comparable treatment response. Race/ethnicity did, however, moderate response with non-white youth faring better in the ET arm of the study. In particular, minority youth in ET had, on average, post-treatment CYBOCS scores consistent with clinical remission whereas their ST counterparts were left with symptoms considered moderately severe. There were no predictors of treatment outcome.

CONCLUSIONS

Minority status predicts poorer response to standard CBT across disorders, suggesting the need for possible treatment adaptations. The present findings highlight one avenue for matching patients to treatments that might optimize outcomes and underscore the value of family involvement in OCD treatment.

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.

Assessment and management of tic disorders and Tourette syndrome by Australian paediatricians

AIM

The diagnosis and management of tic disorders and Tourette syndrome (TS) can be challenging. A better understanding of current approaches by paediatricians is important to inform research and education to improve patient outcomes. We aimed to investigate current assessment and management practices for tics/TS by Australian paediatricians.

METHODS

An online survey was sent to members of the Australian Paediatric Research Network. Primary outcomes of interest included assessment processes, referrals, behavioural interventions and pharmacological management. Four scenarios were presented to elicit information regarding treatment of different types of cases.

RESULTS

Of 340 eligible paediatricians, 139 (41%) responded, with 116 (84%) reporting that they diagnose and manage tics/TS as part of their practice. Questionnaires were used more to identify comorbidities (43%) than to quantify tics (12%). Referrals were most likely to be made to psychologists. Medication was considered important in the management of TS by 45% of respondents, with clonidine identified as the first-choice medication by 69%. There was wide variation in both the pharmacological and behavioural management strategies reported.

CONCLUSIONS

There is substantial practice variation among Australian paediatricians in the assessment and management of patients referred with tics/TS. This may reflect insufficient evidence regarding best practice, as well as limited training in this area. There is a need for improved education of Australian paediatricians in the assessment and management of tics/TS, as well as further research to identify optimal treatments.

Inflammation in Tic Disorders and Obsessive-Compulsive Disorder: Are PANS and PANDAS a Path Forward?

This review and commentary is the product of an invited lecture called "Autoimmunity: PANS/PANDAS" presented at the 2018 Neurobiology of Diseases in Children Symposium in Chicago, IL. The talk addressed clinical and scientific questions and recently published data. At this time, among highly experienced and respected clinicians and researchers spanning relevant disciplines, there is substantial controversy regarding a role for inflammation in producing tics and obsessive-compulsive disorder. This commentary summarizes these controversies, discusses reasons for opposing views on best clinical practices, and concludes with suggestions for pathways forward.

Obsessive-Compulsive Disorder: Autoimmunity and Neuroinflammation

PURPOSE OF REVIEW

Here, we propose to review the immuno-inflammatory hypothesis in OCD given the concurrent incidence of autoimmune comorbidities, infectious stigma, and raised levels of inflammatory markers in a significant subset of patients. A better understanding of the immune dysfunction in OCD may allow stratifying the patients in order to design personalized pharmaco/psychotherapeutic strategies.

RECENT FINDINGS

A persistent low-grade inflammation involving both innate and adaptive immune system with coexisting autoimmune morbidities and stigma of infectious events has been prominently observed in OCD. Hence, specific treatments targeting inflammation/infection are a feasible alternative in OCD. This review highlights that OCD is associated with low-grade inflammation, neural antibodies, and neuro-inflammatory and auto-immune disorders. In some subset of OCD patients, autoimmunity is likely triggered by specific bacterial, viral, or parasitic agents with overlapping surface epitopes in CNS. Hence, subset-profiling in OCD is warranted to benefit from distinct immune-targeted treatment modalities.

PANDAS/PANS in childhood: Controversies and evidence

Since first defined in 1998, paediatric autoimmune neuropsychiatric disorders associated with streptococcal infections (PANDAS) and its later, broader iteration, paediatric acute-onset neuropsychiatric syndrome (PANS), have garnered significant attention and controversy. The role of streptococcal infection in children with explosive onset obsessive-compulsive disorder and new onset tics, the natural history of this entity, and the role of symptomatic and disease-modifying therapies, including antibiotics, immunotherapy, and psychoactive drugs, are all issues that have yet to be definitively addressed. While definitive proof of the autoimmune hypothesis of PANDAS is lacking, given the heightened attention to this entity and apparent rise in use of this diagnostic category, addressing questions around diagnosis, treatment, and etiology is imperative. In this paper, we review current working definitions of PANDAS/PANS, discuss published evidence for interventions related to this entity, and propose a clinical approach to children presenting with acute symptoms satisfying criteria for PANDAS/PANS.

Tics and Tourette syndrome

Tourette syndrome is a heterogeneous disorder. The genetic basis is complex, and both in utero and ex utero environmental factors may modify the phenotypic expression of the disorder. Inflammation related to aberrations in immune activation appears to play a pathogenic role in some cases. Multiple neurochemical pathways are involved. Rather than being a pure movement problem, tics are now understood to also have a sensory component. This has resulted in new psychological therapeutic strategies and other potential treatments. Furthermore, comorbidities are common, particularly attention-deficit hyperactivity disorder, anxiety and obsessive-compulsive disorder, and often cause more difficulties than the tics. The approach to treatment is dependent on the degree and types of impairment. For many patients, education, acceptance and understanding are all that is needed. In more severe cases, psychological and/or pharmacological interventions may be indicated. In this article, the clinical features and pathophysiology of Tourette syndrome are reviewed, and a pragmatic management approach is discussed.

Allergic Diseases and Immune-Mediated Food Disorders in Pediatric Acute-Onset Neuropsychiatric Syndrome

Background: The prevalence and impact of allergic and immune-mediated food disorders in pediatric acute-onset neuropsychiatric syndrome (PANS) are mostly unknown. Objective: We sought to explore the prevalence of atopic dermatitis (AD), asthma, allergic rhinitis (AR), IgE-mediated food allergies (FAs), and other immune-mediated food disorders requiring food avoidance in patients with PANS. In addition, to further understand the extent of food restriction in this population, we investigated the empiric use of dietary measures to improve PANS symptoms. Methods: Pediatric patients in a PANS Clinic and Research Program were given surveys regarding their caregiver burdens, allergic and food-related medical history, and whether food elimination resulted in perception of improvement of PANS symptoms. A review of health records was conducted to confirm that all responses in the survey were concordant with documentation of each patient's medical chart. Results: Sixty-nine (ages 4-20 years) of 80 subjects who fulfilled PANS criteria completed the surveys. Thirteen (18.8%) had AD, 11 (15.9%) asthma, 33 (47.8%) AR, 11 (15.9%) FA, 1 (1.4%) eosinophilic gastrointestinal disorders, 1 (1.4%) food protein-induced enterocolitis syndrome, 3 (4.3%) milk protein-induced proctocolitis syndrome, and 3 (4.3%) celiac disease. Thirty subjects (43.5%) avoided foods due to PANS; elimination of gluten and dairy was most common and was associated with perceived improvement of PANS symptoms (by parents). This perceived improvement was not confirmed with objective data. Conclusions: The prevalence of allergic and immune-mediated food disorders in PANS is similar to the general population as reported in the literature, with the exception of AR that appears to be more prevalent in our PANS cohort. More research will be required to establish whether diet or allergies influence PANS symptoms.

Individualized Immunological Data for Precise Classification of OCD Patients

Obsessive⁻compulsive disorder (OCD) affects about 2% of the general population, for which several etiological factors were identified. Important among these is immunological dysfunction. This review aims to show how immunology can inform specific etiological factors, and how distinguishing between these etiologies is important from a personalized treatment perspective. We found discrepancies concerning cytokines, raising the hypothesis of specific immunological etiological factors. Antibody studies support the existence of a potential autoimmune etiological factor. Infections may also provoke OCD symptoms, and therefore, could be considered as specific etiological factors with specific immunological impairments. Finally, we underline the importance of distinguishing between different etiological factors since some specific treatments already exist in the context of immunological factors for the improvement of classic treatments.

Principles and approaches to the treatment of immune-mediated movement disorders

Immune mediated movement disorders include movement disorders in the context of autoimmune encephalitis such as anti-NMDAR encephalitis, post-infectious autoimmune movement disorders such as Sydenham chorea, paraneoplastic autoimmune movement disorders such as opsoclonus myoclonus ataxia syndrome, and infection triggered conditions such as paediatric acute neuropsychiatric syndrome. This review focuses on the approach to treatment of immune mediated movement disorders, which requires an understanding of the immunopathogenesis, whether the disease is destructive or 'altering', and the natural history of disease. Factors that can influence outcome include the severity of disease, the delay before starting therapy, use of multimodal therapy and whether the course is monophasic or relapsing. Although the four main conditions listed above have different pathophysiological processes, there are general themes that broadly apply including: early diagnosis and treatment is better, minimise the severity of disease, escalate treatment if the patient is not responding to initial treatments, and minimise relapse.

Obsessive-compulsive symptoms in adults with Lyme disease

OBJECTIVE

This study examined the phenomenology and clinical characteristics of obsessive compulsive symptoms (OCS) in adults diagnosed with Lyme disease.

METHOD

Participants were 147 adults aged 18-82 years (M = 43.81, SD = 12.98) who reported having been diagnosed with Lyme disease. Participants were recruited from online support groups for individuals with Lyme disease, and completed an online questionnaire about their experience of OCS, Lyme disease characteristics, and the temporal relationship between these symptoms.

RESULTS

OCS were common, with 84% endorsing clinically significant symptoms, 26% of which endorsed symptoms onset during the six months following their Lyme disease diagnosis and another 51% believed their symptoms were temporally related. Despite the common occurrence of OCS, only 44% of these participants self-identified these symptoms as problematic. Greater frequency of Lyme disease symptoms and disease-related impairment was related to greater OCS. In the majority of cases, symptom onset was gradual, and responded well to psychological and pharmacological treatment. Around half of participants (51%) reported at least some improvement in OCS following antibiotic treatment.

CONCLUSIONS

This study highlights the common co-occurrence of OCS in patients with Lyme disease. It is unclear whether OCS are due to the direct physiological effects of Lyme disease or associated immunologic response, a psychological response to illness, a functional somatic syndrome, or some combination of these.

Treatment of Pediatric Acute-Onset Neuropsychiatric Disorder in a Large Survey Population

OBJECTIVE

The goal of this study was to investigate treatment histories and outcomes in a large community sample of youth with Pediatric Acute-onset Neuropsychiatric Syndrome (PANS), and, where appropriate, to examine the impact of immune deficiency on treatment outcomes.

METHODS

A comprehensive internet-based survey was completed by parents or guardians of youth who had received physician diagnoses of PANS, or by young adults (age 18+) who had themselves been diagnosed by a physician (N = 698). Data regarding the treatment histories of these patients, including the variety of medical and psychological treatments employed and the caregiver- or self-reported response to each, are presented.

RESULTS

The PANS patients in this study had commonly been treated with antibiotic (N = 675), anti-inflammatory (N = 437), and/or psychotropic therapy (N = 378). Response to antibiotic treatment was best when treatment was relatively aggressive, with broad-spectrum antibiotics and courses of >30 days generally producing the best results (i.e., up to 52% of patients achieving a "very effective" response). For immune-deficient patients (caregiver-reported laboratory studies below normal limits; N = 108), use of broad-spectrum antibiotics appeared to be particularly desirable. Anti-inflammatory therapies, including over-the-counter medications such as ibuprofen, were at least "somewhat effective" for most patients. Intravenous immunoglobulin (IVIG) had been used to treat PANS in 193 (28%) of the patients and was at least "somewhat effective" for 89%, although for 18% of these, the effect was not sustained. The highest rate of sustained response to IVIG treatment was seen in immune-deficient patients who received doses of at least 0.8 g/kg IVIG on a regular basis. Psychotropic medications, most commonly SSRIs (38% reported a trial), were commonly employed, but were often ineffective (e.g., 44% found SSRIs "somewhat" to "very effective"). Many patients (N = 473) had received some form of psychotherapy with some benefit, with cognitive behavioral therapy found to be at least somewhat effective in a majority of those treated with this modality.

CONCLUSION

Among the PANS patients represented in this study, relatively aggressive treatment courses targeted at eradicating infection and modulating the inflammatory response appeared to provide the best caregiver-reported therapeutic results, and to be generally well tolerated. Given its relative efficacy and tolerability, treatment targeting the inflammatory response may represent an underutilized approach in this population. The results of this study should be considered in light of the limitations inherent in a self-selected and administered online survey.

Immunotherapeutics in Pediatric Autoimmune Central Nervous System Disease: Agents and Mechanisms

Beyond the major advances produced by careful clinical-radiological phenotyping and biomarker development in autoimmune central nervous system disorders, a comprehensive knowledge of the range of available immune therapies and a deeper understanding of their action should benefit therapeutic decision-making. This review discusses the agents used in neuroimmunology and their mechanisms of action. First-line treatments typically include corticosteroids, intravenous immunoglobulin, and plasmapheresis, while for severe disease second-line "induction" agents such as rituximab or cyclophosphamide are used. Steroid-sparing agents such as mycophenolate, azathioprine, or methotrexate are often used in potentially relapsing or corticosteroid-dependent diseases. Lessons from adult neuroimmunology and rheumatology could be translated into pediatric autoimmune central nervous system disease in the future, including the potential utility of monoclonal antibodies targeting lymphocytes, adhesion molecules for lymphocytic migration, cytokines or their receptors, or complement. Finally, many agents used in other fields have multiple mechanisms of action, including immunomodulation, with potential usefulness in neuroimmunology, such as antibiotics, psychotropic drugs, probiotics, gut health, and ketogenic diet. All currently accepted and future potential agents have adverse effects, which can be severe; therefore, a "risk-versus-benefit" determination should guide therapeutic decision-making.