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

Hypothesizing That Pediatric Autoimmune Neuropsychiatric Associated Streptococcal (PANDAS) Causes Rapid Onset of Reward Deficiency Syndrome (RDS) Behaviors and May Require Induction of "Dopamine Homeostasis"

Pediatric autoimmune neuropsychiatric disorders associated with group A streptococcal infections (PANDAS) is a concept that is used to characterize a subset of children with neuropsychiatric symptoms, tic disorders, or obsessive-compulsive disorder (OCD), whose symptoms are exacerbated by group A streptococcal (GAS) infection. PANDAS has been known to cause a sudden onset of reward deficiency syndrome (RDS). RDS includes multiple disorders that are characterized by dopaminergic signaling dysfunction in the brain reward cascade (BRC), which may result in addiction, depression, avoidant behaviors, anxiety, tic disorders, and/or OCD. According to research by Blum et al., the dopamine receptor D2 (DRD2) gene polymorphisms are important prevalent genetic determinants of RDS. The literature demonstrates that infections like Borrelia and Lyme, as well as other infections like group A beta-hemolytic streptococcal (GABHS), can cause an autoimmune reaction and associated antibodies target dopaminergic loci in the mesolimbic region of the brain, which interferes with brain function and potentially causes RDS-like symptoms/behaviors. The treatment of PANDAS remains controversial, especially since there have been limited efficacy studies to date. We propose an innovative potential treatment for PANDAS based on previous clinical trials using a pro-dopamine regulator known as KB220 variants. Our ongoing research suggests that achieving "dopamine homeostasis" by precision-guided DNA testing and pro-dopamine modulation could result in improved therapeutic outcomes.

Tourette syndrome or PANDAS-a case report

Tourette syndrome (TS), a relatively common disorder, has been gaining more attention during the past two decades because of an increased number of reports. Nevertheless, it is still not completely understood. Furthermore, a clinical entity called "pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections" (PANDAS) has been introduced, which describes a tic disorder, accompanied by psychiatric disorders such as obsessive compulsive disorder (OCD), after a streptococcal infection in childhood. We present a case report of a 19-year-old adolescent Ukrainian female, with a history of anxiety disorder and OCD, who, despite TS remission during childhood, presented with new-onset motor and phonic tics after 1 month of severe tonsillitis. Blood and cerebrospinal cultures showed Streptococcus pyogenes, with magnetic resonance imaging revealing hypo-intense changes in the caudate nucleus on both sides. Treatment with clonazepam and fluoxetine, along with behavioral therapy, have improved the severity of her condition. This report presents a case of TS reemergence against the background of immunological reaction or PANDAS with a late adolescent onset.

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.

Cytokine, chemokine and BDNF levels in medication-free pediatric patients with obsessive-compulsive disorder

The aim of this study was to investigate whether the serum levels of IL-12, IL-17, TGFβ, TNF-alpha, sTNFR1, sTNFR2, IL-1β, CCL3, CCL24, CXCL8, and BDNF are associated with obsessive-compulsive disorder (OCD) in medication-free children. A total of 44 (22 boys/22 girls) medication-free children with OCD and 40 (23 boys/17 girls) healthy controls were included in this study. The severity of the OCD symptoms were assessed by the Children's Yale-Brown Obsessive-Compulsive Scale and the Maudsley Obsessive-Compulsive Inventory. The Children's Depression Inventory and the Screen for Child Anxiety-Related Emotional Disorders were applied to the children in order to determine depression and anxiety levels. IL-17, IL-12, TGF β, TNF-alpha, sTNFR1, sTNFR2, IL-1β, CCL3, CCL24, CXCL8, and BDNF levels were measured by enzyme-linked immunosorbent assay. Multivariate analysis of covariance (MANCOVA) revealed a significant main effect on both groups for the levels of serum cytokine, chemokine, and BDNF, an effect that was independent of severities of depression and anxiety [Pillai's Trace V = 0.371, F (11, 70) = 3.756, p < 0.001, hp² = 0.187]. Analysis of covariance (ANCOVA) indicated that serum TNF-alpha levels were significantly higher in the OCD group than in the control group (p < 0.001). In contrast, serum IL-12 levels were significantly lower in the OCD group than in the control group (p = 0.014). These findings suggest that TNF-alpha and IL-12 may play a role in the pathophysiology of OCD in children. The causal relationship between these proinflammatory cytokines and pediatric OCD requires further investigation.

Neuropsychiatric Aspects of Infectious Diseases: An Update

Among the critically ill, infectious diseases can play a significant role in the etiology of neuropsychiatric disturbances. All critical care physicians are familiar with delirium as a secondary complication of systemic infection. This article focuses on key infectious diseases that commonly and directly produce neuropsychiatric symptoms, including direct infection of the central nervous system, human immunodeficiency virus infection, and AIDS.

Central nervous system vasculitis in adults and children

Primary angiitis of the central nervous system (PACNS) is an inflammatory brain disease targeting the cerebral blood vessels, leading to a wide spectrum of signs and symptoms, including neurologic deficits, cognitive dysfunction, and psychiatric symptoms. The inflammation could be reversible if diagnosed and treated early. The diagnosis requires the careful consideration and rapid evaluation of systemic underlying conditions and disease mimics. The differential diagnosis is distinctly different for angiography-positive and -negative PACNS subtypes and differs depending on age, so there is childhood PACNS or adult PACNS. Distinct disease subtypes have been described, with characteristic disease course, neuroimaging findings, and histopathologic features. Novel and traditional biomarkers, including von Willebrand factor antigen and cytokine levels, can help diagnose, and define subtype and disease activity. Treatment of PACNS should be tailored to the disease subtypes and clinical symptoms. Beyond immunosuppression it should include medications to control symptoms in order to support and enhance the child's or adult's ability to actively participate in rehabilitation. The mortality of PACNS has decreased; studies determining the morbidity and its determinants are urgently needed.

Post-infectious group A streptococcal autoimmune syndromes and the heart

There is a pressing need to reduce the high global disease burden of rheumatic heart disease (RHD) and its harbinger, acute rheumatic fever (ARF). ARF is a classical example of an autoimmune syndrome and is of particular immunological interest because it follows a known antecedent infection with group A streptococcus (GAS). However, the poorly understood immunopathology of these post-infectious diseases means that, compared to much progress in other immune-mediated diseases, we still lack useful biomarkers, new therapies or an effective vaccine in ARF and RHD. Here, we summarise recent literature on the complex interaction between GAS and the human host that culminates in ARF and the subsequent development of RHD. We contrast ARF with other post-infectious streptococcal immune syndromes - post-streptococcal glomerulonephritis (PSGN) and the still controversial paediatric autoimmune neuropsychiatric disorders associated with streptococcal infections (PANDAS), in order to highlight the potential significance of variations in the host immune response to GAS. We discuss a model for the pathogenesis of ARF and RHD in terms of current immunological concepts and the potential for application of in depth "omics" technologies to these ancient scourges.

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."

Musical obsessions: a comprehensive review of neglected clinical phenomena

Intrusive musical imagery (IMI) consists of involuntarily recalled, short, looping fragments of melodies. Musical obsessions are distressing, impairing forms of IMI that merit investigation in their own right and, more generally, research into these phenomena may broaden our understanding of obsessive-compulsive disorder (OCD), which is phenomenologically and etiologically heterogeneous. We present the first comprehensive review of musical obsessions, based on the largest set of case descriptions ever assembled (N=96). Characteristics of musical obsessions are described and compared with normal IMI, musical hallucinations, and visual obsessional imagery. Assessment, differential diagnosis, comorbidity, etiologic hypotheses, and treatments are described. Musical obsessions may be under-diagnosed because they are not adequately assessed by current measures of OCD. Musical obsessions have been misdiagnosed as psychotic phenomena, which has led to ineffective treatment. Accurate diagnosis is important for appropriate treatment. Musical obsessions may respond to treatments that are not recommended for prototypic OCD symptoms.

The involvement of secondary neuronal damage in the development of neuropsychiatric disorders following brain insults

Neuropsychiatric disorders are one of the leading causes of disability worldwide and affect the health of billions of people. Previous publications have demonstrated that neuropsychiatric disorders can cause histomorphological damage in particular regions of the brain. By using a clinical symptom-comparing approach, 55 neuropsychiatric signs or symptoms related usually to 14 types of acute and chronic brain insults were identified and categorized in the present study. Forty percent of the 55 neuropsychiatric signs and symptoms have been found to be commonly shared by the 14 brain insults. A meta-analysis supports existence of the same neuropsychiatric signs or symptoms in all brain insults. The results suggest that neuronal damage might be occurring in the same or similar regions or structures of the brain. Neuronal cell death, neural loss, and axonal degeneration in some parts of the brain (the limbic system, basal ganglia system, brainstem, cerebellum, and cerebral cortex) might be the histomorphological basis that is responsible for the neuropsychiatric symptom clusters. These morphological alterations may be the result of secondary neuronal damage (a cascade of progressive neural injury and neuronal cell death that is triggered by the initial insult). Secondary neuronal damage causes neuronal cell death and neural injury in not only the initial injured site but also remote brain regions. It may be a major contributor to subsequent neuropsychiatric disorders following brain insults.

Fascinating interaction between host and pathogen

Clinical manifestations of disease depend upon host's immune response that is induced by pathogen and modified by the host's innate and adaptive immunity. Immunocompetent children of similar age and nutrition evoke different responses to the same pathogen varying from benign to potentially fatal condition. This results in diverse clinical presentations of a disease, that is different from the standard expected pattern and thus, poses a diagnostic challenge. Even, subsequent progression of a disease is also variable. It is the balance between immune stimulation, immune suppression and immune tolerance that decides the outcome. In case of balanced response, child recovers completely without any damage. However at times, cure is at the expense of permanent sequalae while in case of unfavourable immune response, survival may not be certain inspite of successful therapy. Symptoms and physical signs of primary disease often overlap with those caused by host's immune response. In such a situation, it is difficult to decide whether therapy of primary disease has failed due to drug resistance or whether persistence or deterioration is the result of immune response. Occasionally pathogen can transform into "superantigen" that may lead to "cytokine storm". Resulting immune-mediated complications may endanger life and at best, treated symptomatically. Immune suppressive drugs such as steroids, chemotherapeutic agents, IVIG or specific antibodies may not be able to suppress undesirable immune response. It is not just the immune suppression that is required but ideally immune modulation. Immune modulation refers to enhancing protective responses while avoiding destructive ones. At present, science falls short of anticipating harmful immune responses and lacks specific immune intervention.Laboratory test results are also dependent on host response and hence need cautious interpretation based on clinical profile in consideration with multiple variables. In final analysis, fight between host and pathogen is a complex one and often unpredictable. It is hoped that most children evoke favourable response but pediatrician has to be watchful even in the most benign disease.

Childhood central nervous system vasculitis

Inflammatory brain diseases in childhood are underrecognized and lead to devastating yet potentially reversible deficits. New-onset neurologic or psychiatric deficits in previously healthy children mandate an evaluation for an underlying inflammatory brain disease. Distinct disease entities, such as central nervous system (CNS) vasculitis, are now being increasingly reported in children. Clinical symptoms, initial laboratory test, and neuroimaging studies help to differentiate between different causes; however, more invasive tests, such as lumbar puncture, conventional angiography, and/or brain biopsy, are usually necessary before the start of treatment. This article focuses on childhood CNS vasculitis.

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.

Current insights in invasive group A streptococcal infections in pediatrics

A rising incidence of invasive group A Streptococcus infections (IGASI) has been noted in children in the past three decades. The relative frequency of the infection types showed marked differences to IGASI in adults, and severity of the disease resulted in a mortality rate usually comprising between 3.6% and 8.3%. The emm1-type group A Streptococcus (GAS) subclone displaying a particular pattern of virulence factors was widely disseminated and prevalent in children with IGASI while the emm3-type GAS subclone appeared as a recent emerging genotype. However, the implication of these hypervirulent clones in the increase of IGASI in children is still controversial. Recent advances in our knowledge on pathogenesis of IGASI underlined that deregulation of virulence factor production, individual susceptibility, as well as exuberant cytokine response are important factors that may account for the severity of the disease in children. Future changes in IGASI epidemiology are awaited from current prospects for a safe and effective vaccine against GAS. IGASI are complex infections associating septic, toxic, and immunological disorders. Treatment has to be effective on both the etiologic agent and its toxins, due to the severity of the disease associated to the spread of highly virulent bacterial clones. More generally, emergence of virulent clones responsible for septic and toxic disease is a matter of concern in pediatric infectiology in the absence of vaccination strategy.

Systematic review of proinflammatory cytokines in obsessive-compulsive disorder

Several studies have examined levels of proinflammatory cytokines, such as tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6. This meta-analysis was conducted to examine the association between obsessive-compulsive disorder (OCD) and plasma serum levels of proinflammatory cytokines. Twelve studies met inclusion criteria. The meta-analysis demonstrated a significant reduction in IL-1β levels in OCD. No significant difference in plasma levels of IL-6 or TNF-α was demonstrated. Stratified subgroup analysis revealed possible moderating effects of age and medication use on IL-6 levels. Studies including children on psychotropic medication had lower plasma IL-6 levels. Stratified subgroup analysis revealed a moderating effect of comorbid depression on TNF-α levels. Elevated TNF-α levels were reported in studies that included individuals with comorbid depression. Future studies examining immune function in OCD should adjust for potential confounding due to medication use and comorbid depression. Further studies assessing cerebrospinal fluid cytokine levels in OCD are also needed.

Prevalence of anti-basal ganglia antibodies in adult obsessive-compulsive disorder: cross-sectional study

BACKGROUND

Symptoms of obsessive-compulsive disorder (OCD) have been described in neuropsychiatric syndromes associated with streptococcal infections. It is proposed that antibodies raised against streptococcal proteins cross-react with neuronal proteins (antigens) in the brain, particularly in the basal ganglia, which is a brain region implicated in OCD pathogenesis.

AIMS

To test the hypothesis that post-streptococcal autoimmunity, directed against neuronal antigens, may contribute to the pathogenesis of OCD in adults.

METHOD

Ninety-six participants with OCD were tested for the presence of anti-streptolysin-O titres (ASOT) and the presence of anti-basal ganglia antibodies (ABGA) in a cross-sectional study. The ABGA were tested for with western blots using three recombinant antigens; aldolase C, enolase and pyruvate kinase. The findings were compared with those in a control group of individuals with depression (n = 33) and schizophrenia (n = 17).

RESULTS

Positivity for ABGA was observed in 19/96 (19.8%) participants with OCD compared with 2/50 (4%) of controls (Fisher's exact test P = 0.012). The majority of positive OCD sera (13/19) had antibodies against the enolase antigen. No clinical variables were associated with ABGA positivity. Positivity for ASOT was not associated with ABGA positivity nor found at an increased incidence in participants with OCD compared with controls.

CONCLUSIONS

These findings support the hypothesis that central nervous system autoimmunity may have an aetiological role in some adults with OCD. Further study is required to examine whether the antibodies concerned are pathogenic and whether exposure to streptococcal infection in vulnerable individuals is a risk factor for the development of OCD.

Early versus late onset obsessive-compulsive disorder: evidence for distinct subtypes

The distinction between early versus late onset is important for understanding many different kinds of disorders. In an effort to identify etiologically homogeneous subtypes of obsessive-compulsive disorder (OCD), numerous studies have investigated whether early onset OCD (EO) can be reliably distinguished from a comparatively later onset form of the disorder (LO). The present article presents a systematic review and evaluation of this subtyping scheme, including meta-analyses and re-analyses of raw data. Regarding the latter, latent class analyses of nine datasets, including clinical and community samples, consistently indicated that age-of-onset is not a unimodal phenomena. Evidence suggests that there are two distinguishable groups; EO (mean onset 11 years) and LO (mean onset 23 years). Approximately three-quarters of cases of OCD (76%) were classified as EO. Meta-analyses indicated that EO, compared to LO, is (a) more likely to occur in males, (b) associated with greater OCD global severity and higher prevalence of most types of OC symptoms, (c) more likely to be comorbid with tics and possibly with other putative obsessive-compulsive spectrum disorders, and (d) associated with a greater prevalence of OCD in first-degree relatives. EO and LO were also distinguishable on other psychosocial and biological variables. Overall, results support the view that EO and LO are distinct subtypes of OCD. Comparisons with other, potentially overlapping OCD subtyping schemes are discussed, implications for DSM-V are considered, and important directions for future investigation are proposed.