RESUMEN
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.
RESUMEN
A comparison of clinical features and adult outcome in adolescents with three types of psychotic disorders: schizophrenic (SPh), schizoaffective (SA) and bipolar with psychotic features (BPP). Subjects (n = 41) were finally diagnosed (DSM-IV criteria) with SPh (n = 17), SA (n = 11) or BPP (n = 13). Clinical evaluation took place at onset and at a 3-year follow-up in all 41, and at least after 5 years in 36 patients. Symptoms were rated on the basis of the Positive and Negative Syndrome Scale (PANSS), integrating items from the Brief Psychiatric Rating Scale (BPRS) and the Kiddie Schedule for Affective Disorders and Schizophrenia for School-Age Children-Present and Lifetime Version (K-SADS-PL). The Children Global Assessment Scale (C-GAS) and the Global Assessment Scale (GAF) were used to evaluate global functioning. Significant differences in clinical features were found in the three diagnostic groups as regards several parameters, some present on one and not on other rating scales, underscoring the insufficiency of a single scale for accurate analysis of the features of a psychotic disorder. At onset, a comparison using the simple presence/absence of symptoms showed scant differences among groups, while differences emerged if symptom severity was included in the comparison. Functioning at 3- and 5-year follow-ups showed a significantly better outcome in the BPP group and more substantial deterioration, with similar evolution, in the SPh and SA groups. The integration of several rating scales differentiated between diagnostic groups more effectively. The similar adult functioning outcome in the SPh and SA groups showed how difficult it is to clearly separate these two disorders.