[Pharmacoresistance to psychotropic drugs in children and adolescents: Pharmacogenetic anomalies of cytochrome P450 2D6]. / La pharmacorésistance aux psychotropes chez l'enfant et l'adolescent : recherche d'anomalies pharmacogénétiques du cytochrome P450 2D6.

OBJECTIVES: Some patients in child and adolescent psychiatry present resistance to psychotropic drugs, often resulting in polytherapy, an increased risk of adverse events, and more frequent and longer hospitalisation. Psychotropic drugs are mainly metabolised in the liver, in particular by the CYP2D6 subunit of cytochrome P450. Anomalies such as a duplication of the CYP2D6 gene related to an ultra-rapid metaboliser phenotype has been described to be linked to clinical efficacy. However, little research has been done in child and adolescent psychiatry. METHODS: A multi-centric cross-sectional study in the southeast of France explored the relation between pharmaco-resistance to psychotropic drugs and the prevalence of duplications or polymorphisms of CYP2D6 associated with an ultra-rapid phenotype in children and adolescents with severe mental health disease. RESULTS: Twenty-two patients have been included. The presence of an ultra-rapid phenotype concerns one patient in our study. A second patient presents a slow metaboliser phenotype. CONCLUSIONS: This study allows a clinical characterisation of the population of pediatric drug-resistant patients whose severity and the impact of their pathology are major and require long-term care associated with repeated hospitalisations, multiple drug prescriptions and numerous side effects. However, a link between drug resistance to psychotropic drugs and CYP2D6 UFM abnormalities could not be confirmed. An additional pharmacogenetic analysis by a panel of genes applied in the metabolism, transport and action of psychotropic drugs should be considered to answer questions about the resistance and independent effects of CYP2D6.

[Psychiatric consequences of Covid 19 pandemic in the pediatric population]. / Conséquences psychiatriques de la pandémie de la Covid 19 chez l'enfant et l'adolescent.

The objective of this article is to present a literature review concerning the psychiatric consequences associated with the Covid 19 pandemic, in the pediatric population. This review is realized with Pubmed Database, using Covid 19, Coronavirus, child, children, adolescent, mental health, psychiatric or psychological consequences as keywords. We propose to present an inventory of current research based on three factors: fear linked to the pandemic, the consequences of the stay-at-home confinement, and the risks of cumulative trauma. We will present three clinical vignettes of children who were followed during the health crisis following the development of symptoms related to the health situation. We will end with some perspectives on the management of the health crisis by child and adolescent psychiatry services.

[Neurodevelopmental Disorders, Psychiatric Comorbidities and Associated Pathologies in Patients with Childhood-Onset Schizophrenia and Premorbid Autistic Symptoms.] / Atteintes Neurodéveloppementales, Comorbidités Psychiatriques Et Pathologies Associées Chez Des Patients Atteints de Schizophrénie Très Précoce Avec Symptômes Autistiques Prémorbides.

INTRODUCTION: Childhood-Onset Schizophrenia (COS) is a rare (1/40000), severe and neurodevelopmental form of schizophrenia beginning before 13 years of age. Little is known about comorbidities and specific COS-related disorders. Thus, the objective of our study was to evaluate them from a psychiatric, neurodevelopmental and somatic perspective. METHOD: This is an ancillary study of the GenAuDiss protocol. A standardized psychiatric interview (K-SADS-PL DSM5) and a neuropsychological assessment (WISC-V/WAIS-IV) were carried out in outpatients with COS as well as a medical history collection concerning pregnancy, perinatal period, development, biography and medical and psychiatric, personal, and family history. RESULTS: 20 outpatients were included. The mean age of onset of COS was 8.90 years (+/- 2.30). Psychiatric comorbidities (DSM5) were Attention Deficit Hyperactivity Disorder (15/20 patients), Anxiety Disorders (14/20) and Autism Spectrum Disorder (13/20). The average IQ was 70.26 (+/- 18.09). A language delay and a break in school career were noted in 18/20 patients. Finally, the main associated somatic disorder was asthma (15/20 patients). DISCUSSION: We highlighted in our patients with COS a high frequency of comorbidities including at least one systematic psychiatric disorder. However, although COS is a severe condition impacting the patient, his family and society, its management remains essentially symptomatic. In clinical practice, it is necessary to look for all these comorbidities and to manage them in order to improve the overall quality of care.

INTRODUCTION: La schizophrénie très précoce (STP) est une forme rare (1/40000), grave et neurodéveloppementale de schizophrénie débutant avant 13 ans. Les comorbidités et atteintes associées spécifiques des STP étant peu étudiées, l'objectif de notre étude a été de les évaluer sur le plan psychiatrique, neurodéveloppemental et somatique. MÉTHODE: Il s'agit d'une étude ancillaire du protocole GenAuDiss. Un entretien psychiatrique standardisé (K-SADS-PL DSM5) et un bilan neuropsychologique (WISC-V/WAIS-IV) ont été effectués chez les patients atteints de STP ainsi qu'une anamnèse concernant la grossesse, la périnatalité, le développement, la biographie et les antécédents médicaux et psychiatriques, personnels et familiaux. RÉSULTATS: 20 sujets ont été inclus. L'âge moyen de début du trouble était de 8,90 ans (+/−2,30). Les comorbidités psychiatriques (DSM5) étaient le Trouble Déficitaire de l'Attention avec Hyperactivité (15/20 patients), les troubles anxieux (14/20) et le Trouble du Spectre de l'Autisme (13/20). Le QI moyen était de 70,26 (+/−18,09). Un retard de langage et une rupture de parcours scolaire étaient notés chez 18/20 patients. Enfin, l'affection somatique principale associée était l'asthme (15/20 patients). DISCUSSION: Nous avons mis en évidence chez nos patients atteints de STP une fréquence élevée de comorbidités dont au moins un trouble psychiatrique systématique. Or, bien que la schizophrénie infantile soit une pathologie de pronostic sévère impactant le patient, sa famille et la société, sa prise en charge demeure essentiellement symptomatique. En pratique clinique, il apparaît nécessaire de rechercher systématiquement ces comorbidités et de les prendre en charge pour améliorer la qualité globale des soins.

[Suicidal attempts in child and adolescent and bipolar disorders]. / Tentative de suicide chez l'enfant et l'adolescent et bipolarité.

BACKGROUND: Child and adolescent psychiatrists are frequently confronted with suicide attempts and comorbid mood disorders. Diagnoses of juvenile bipolar disorders (BD) are rare and controversial and standardized assessment is helpful for a reliable diagnosis. The main objective of this study was to identify the number of juvenile bipolar disorder diagnoses according to DSM-5 criteria in a population of children and adolescents hospitalized for suicide attempts. Secondary objectives were the assessment of a patient's characteristics and the comparison of suicide attempt recurrence during 12 months of follow-up. METHODS: This current practice study consecutively included children and adolescents aged 6 to 18 years and hospitalized for a suicide attempt in a French University Pediatric Hospital over a 4-month period. Patients were assessed at baseline, at 3 months and at 12 months. The standardized assessment was realized by the investigator using semi-structured interview K-SADS-PL (2013) to diagnose juvenile bipolar disorders based on DSM-5 criteria. Clinical diagnoses based on medical charts and according to ICD-10 criteria were also collected at 12-month follow-up. Standardized assessment was completed by the French validated K-SADS-PL (2004) for comorbidities (DSM-IV), dimensional assessment by MADRS-YMRS-ARI-C-SSR, and C-GAS at inclusion. Patients were divided into two groups: (1) those presenting juvenile bipolar disorder according to DSM 5 (BD+) and (2) those without criteria for bipolar disorder (BD-). Suicide risk factors and suicide attempt relapse were assessed at 3 and 12 months of follow-up. RESULTS: Twenty-six inpatients (22 female and 4 male) aged 14.5 years (SD 1,5) were consecutively included. Twenty patients were followed up during the 12-month period. At baseline, 5 patients (19.2 %) presented a diagnosis of BD (DSM-5): 1 BD type 2, 2 non specified BD, 2 cyclothymic disorders. According to the medical charts (ICD-10), none of the patients had been diagnosed with BD but had diagnoses of dysthymia, of borderline personality disorder and of conduct disorder corresponding to DMDD in 3, 2 and 1 patient respectively. During the 12-month follow-up, 9 patients of the BD- group and none of the BD+ presented recurrence of suicide attempt with 67 % during the first 3 months and 3 patients with multi-relapses. These 3 patients were female adolescents out of care and carrying at least three suicide risk factors. Six patients have been lost to follow-up (1 BD+, 5 BD-). In the BD+ group, 3 patients out of 4 had a persistent diagnosis (DSM-5) of BD at 12 months. CONCLUSION: In our adolescent population hospitalized for suicidal attempt, 19,2 % present BD using DSM-5 criteria. Diagnoses are stable during 12 months of follow-up, but under diagnosed in current clinical practice. DSM-5 standardized assessment appears to be very important to diagnose juvenile BD, mandatory for medium and long-term psychiatric follow-up, especially for suicide prevention and psychopharmacologic therapeutics. Nevertheless, no recurrence of suicide attempts has been observed in our BP+ group, contrary to BP-, possibly due the absence of BP 1 disorder.

[Emergency child psychiatry response following the 14 July 2016 terrorist attack in Nice, France]. / Réponse pédopsychiatrique d'urgence à la suite de l'attentat terroriste du 14 juillet 2016 à Nice, en France.

The attack on 14 July 2016 in Nice on the Promenade des Anglais caused major trauma for individuals directly or indirectly impacted by the horror of the terrorist attack, mainly families and children. It was the first time in France that a pediatric population aged from several months to 18 years was impacted by an event of such magnitude. The literature underlines the importance of taking into account, over the longer term, the side effects of such a psychotrauma in the pediatric population, especially in children under 6 years of age. From the night of 14 July 2016, a pediatric medical and psychological emergency unit (CUMP) was set up within the CHU-Lenval pediatric hospital. This has been a unique experience in Europe, which mobilized 227 caregivers. A total of 728 individuals were seen in consultations, including 385 children between 3 months and 17.7 years. The article outlines the main lines of its organization and its objectives.

[Carbamazepine and psychotropic treatment interaction: Two case studies of carbamazepine overdosage]. / Surdosage en carbamazépine par interaction avec les psychotropes : à propos de deux cas.

Drug interaction is a frequent situation in pediatrics and child psychiatry. Carbamazepine (CBZ) is an antiepileptic drug used as a mood stabilizer in child psychiatry. CBZ is known to be a potent inducer of various CYP isoenzymes of cytochrome P450, which might result in a decrease in the plasma concentration of associated treatments. We describe two cases of CBZ overdosage in adolescent inpatients (14 and 16 years). The patients were treated with risperidone associated with fluoxetine in one and with loxapine in the other case, and CBZ was introduced as a mood stabilizer. Patients presented typical clinical symptoms (fatigue, dizziness, gastrointestinal signs, blurred vision). Overdosage was confirmed by an elevated CBZ plasma concentration (17 and 15.5 mg/L, therapeutic range 4-12 mg/L). We recommend introducing CBZ very progressively in patients treated with psychotropics, particularly when it is associated to several treatments. An intensification of clinical and biological follow-up with early plasma concentration testing should allow for better treatment adjustment.

[Prosocial intervention in children and adolescents with autism spectrum disorder without intellectual disability: benefits of videotaping therapy sessions]. / Intervention pro-sociale chez l'enfant et l'adolescent avec trouble du spectre autistique sans déficit intellectuel : intérêt du support vidéo.

INTRODUCTION: The category of pervasive developmental disorders (PDD) without intellectual disability (including Asperger syndrome and high-functioning autism) has increased steadily among individuals since the 1980s. Although some symptoms may decrease with age, functional disability persists and is largely related to abnormalities in social interaction. Within the framework of PDD without intellectual disability, improving social skills appears to be a primary target for intervention programs. Despite a recent increase in the number of studies on this topic, few validated programs are yet available for clinical settings. BACKGROUND: We have developed an intervention targeting the improvement of social skills from the analysis of video sequences. The goal of this intervention is to promote communication within the group through sharing their interests and emotions, and to enhance the understanding of social situations. In order to assess the efficiency of this intervention, we have conducted a prospective, open, and uncontrolled study. First, it aimed at assessing the immediate effect of our intervention on a single social skill (communication) in an experimental situation (in the group) and in an ecological situations (family and school). Second, this study aimed at assessing the effects of this intervention on the subjects' social adjustment. METHOD: This study included 16 individuals with high-functioning autism/Asperger syndrome. Participants were evaluated before and after a 6-month video-based training using measures of socio-communicative and adaptive skills. RESULTS: Results revealed a statistically significant increase in the communication skills not only in the group (15.5%), but also at home (13.7%) and at school (8.7%). The evaluation of socio-adaptive behavior indicates a statistically significant increase in communication (12%), family (7%) and social autonomy (8%), and leisure activities (8%). DISCUSSION: The communication and social adjustment scores obtained upon inclusion were low, despite low autistic intensity scores. However, the improvement at six months was significant for most studied variables. These results are consistent with our clinical findings and seem partly explained by the use of video supports as the mediator of exchanges within the group. However, because of some methodological limitations, the conclusions on the effects of the intervention should be nuanced. CONCLUSIONS: This type of intervention seems to be an interesting therapeutic indication for individuals with high-functioning autism/Asperger syndrome. The first results are encouraging, and all participants enjoyed attending the meetings. These conclusion elements encourage us to continue this intervention and to pursue further research by studying the impact on the individuals' quality of life.

[Improve safety monitoring of antipsychotics in the French pediatric population]. / Améliorer la surveillance de la tolérance pédiatrique des antipsychotiques en France.

In France, as in the rest of the world, the prescription of second generation antipsychotics is on the rise in the pediatric population. At the same time, the use of first generation antipsychotics continues, although it is declining in France as in other countries. In France, we lack data on the pediatric population to ensure a safe prescription, unlike other countries such as Canada and the United States. This is disturbing when many adverse events, potentially serious for young patients' health (neuromuscular complications, risk factors, cardiovascular problems) are beginning to be identified. This article reports the current French and international knowledge on antipsychotics in the pediatric population. It appears that data in the French population are nearly nonexistent and that the methodological tools used are not always relevant (population already exposed to psychotropic drugs, short studies, debatable rating scale and somatic parameters). Within this context, a safety monitoring procedure for the naive pediatric population treated with antipsychotics was developed (ETAPE study) to determine the incidence of adverse events appearing with these drugs. Safety monitoring during the 12-month study period will include clinical assessments and laboratory testing. These assessments will be performed before treatment and at 1, 3, 6, 9, and 12 months after the introduction of the antipsychotic drug. This study received funding from the National Security Agency of Medicines (ANSM 2012 No. 40). The results should contribute to educating all practitioners (general physicians, pediatricians, psychiatrists, child psychiatrists) on adverse events, helping practitioners with prescribing decisions, reinforcing the French system of monitoring adverse events caused by atypical antipsychotic drugs, and developing recommendations to improve the safety of atypical antipsychotic drugs in child psychiatry.

[Follow-up of a 16-year-old adolescent with early-onset schizophrenia and catatonic symptoms]. / Suivi thérapeutique d'un adolescent de 16ans souffrant de schizophrénie précoce avec symptômes catatoniques.

INTRODUCTION: The aim of this paper is to underline the need of a systematic monitoring (1) of atypical antipsychotics and (2) of catatonic symptoms in child psychiatry. We present in this paper the clinical history of a 16-year-old adolescent inpatient needing a prescription of atypical antipsychotic drug. We present the most relevant results of our clinical monitoring over 7 months. CASE REPORT: A 16-year-old Caucasian male adolescent, by the name of Paul, was admitted in August 2009 to an Adolescent University Psychiatry Unit for an acute psychotic disorder. On admission, he presented paranoid delusion, auditory hallucinations and impulsive movements. The score on the Bush-Francis Catatonia Rating Scale (BFCRS) was 17 (the threshold score for the diagnosis of catatonic symptoms is 2). Laboratory tests showed the lack of blood toxic levels, creatine phosphokinase (CPK) level was 684 IU/L. Paul was treated with clonazepam (0.05 mg/kg/d). This particular day was considered to be day #1 of the clinical drug monitoring. Immediately after, regular follow-up of catatonic symptoms was performed. On day #15, the CPK level returned to normal with improvement of clinical catatonia but with still a score of 4 on the BFCRS scale. Auditory hallucinations and delusion persisted. Risperidone treatment was begun (1mg/d and 1.5mg/d after 24 hours), associated with oral clonazepam (0.05 mg/kg/d). On day #17, after 48 hours of improvement of delusion, the catatonic symptoms rapidly worsened. Risperidone was stopped; Paul was transferred to intensive care where he was treated with clonazepam IV (0.1mg/kg/d). The score on BFCRS scale was 20, Paul presented no fever and the CPK level was below 170 IU/L. The diagnosis was a relapse of the catatonic episode, which was caused by the administration of risperidone. On day #24, no improvement in the state of catatonia was obtained. The treatment was changed with the following combination of medicine: clonazepam (0.1mg/kg/d)-lorazepam (5mg/d)-carbamazepine (10mg/kg/d). With this combination, the state of catatonia improved quickly and on day #31, he was transferred to the adolescent psychiatry unit. However, delusion and hallucinations persisted; a treatment with olanzapine was started at 5mg/d and then progressively increased to 20mg/d for 10 days. On day #115, after 3 months with olanzapine, no improvement of the hallucinatory and delusional symptoms was observed; the diagnosis of early-onset refractory schizophrenia was established. The Therapeutic Drug Monitoring (TDM) confirmed the good compliance; clozapine was introduced and progressively increased up to 250 mg/d. On day #199, after 3 months under clozapine (250 mg/d), the speech was coherent and delusion was rare. During this period, no relapse of the catatonic state was observed. DISCUSSION: In this case, the BFCRS scale was sensitive to catatonic symptom diagnosis. CPK levels vary differently for each atypical antipsychotic and are not a specific complication indicator. In complex cases, the TDM seems useful when choosing atypical antipsychotics. CONCLUSION: The association of two benzodiazepines (clonazepam-lorazepam) with carbamazepin allowed the improvement of catatonic symptoms. Plasma levels of atypical antipsychotics helped the practitioner in deciding the type of care required: plasma levels confirmed the patient's treatment adherence and thus reinforced the choice of clozapine.

[Catatonia in a 14 year-old girl: treatment with clorazepam and carbamazepine, a 10-year follow-up]. / Catatonie chez une adolescente de 14 ans: traitement par clorazépam et carbamazépine et évolution à dix ans.

INTRODUCTION: Child and adolescent catatonia has been poorly investigated. Moreover, diagnosis criteria only exist for adult psychiatry, and there are no therapeutic guidelines. The aim of this paper is to describe the case of a 14-year-old girl presenting an overlap between psychogenic and neuroleptic induced catatonia, acute treatment and ten year's follow-up. CASE REPORT: A 14-year-old Caucasian French girl, Elsa, was admitted in February 1998 to a University adolescent mental health center with an acute psychotic disorder. She showed agitation, impulsivity (sudden engagement in inappropriate behaviour), paranoid delusions, visual and auditory hallucinations, diurnal and nocturnal urinary incontinence, lack of self-care, inadequate food intake because of fear of poisoning, and vomiting after meals leading to rapid weight loss of 5 kg. Clinical examination, laboratory tests, EEG and RMI were normal. Toxicological tests were negative. Her IQ, assessed six months before admission, was in the dull average range (70-75). Elsa was treated with loxapine 150 mg per day for one week without improvement and this was then replaced by haloperidol 30 mg per day. One week after the start of haloperidol her agitation, impulsivity, and hallucinatory symptoms decreased. Twenty four days after loxapine introduction and 17 days after the haloperidol, her condition deteriorated rapidly over less than 48 hours. She exhibited immobility, minimal response to stimuli, staring and catalepsy with waxy flexibility. The diagnosis of catatonia was established. Examination revealed tremulous extremities, tachychardia (110 pm) and apyrexia. Creatine phosphokinase levels were 106 UI/l (normal range 0-250). Human immunodeficiency virus, hepatitis, listeria and Lyme serology were negative. Cerebrospinal fluid analysis was normal. Haloperidol was stopped and intravenous clonazepam 5mg/kg was begun. It was not possible to obtain signed consent from the two parents for Electroconvulsive therapy. The patient was transferred to a pediatric intensive care unit. The treatment was standard parenteral nutrition, nursing, intravenous clonazepam 0.05 mg/kg, with regular attendance by a child psychiatrist. Elsa stayed three weeks in this condition. She then began to notice the child psychiatrist, and a few days later she was able to carry out simple requests. Elsa was transferred to an adolescent psychiatric unit. As soon as she could eat by herself again, carbamazepine 400mg per day was begun. Her agitation reduced at a carbamazepine level of 7 mg/l. One month later her condition was stable. However, language difficulties persisted for a further six months. One year after the episode she scored 66 on a repeat IQ test and her RMI was normal. She exhibited no significant residual symptoms except some cognitive impairment. She integrated into a special education facility. These attempts to stop the carbamazepine were followed by depressed mood, aggressiveness and impulsivity; carbamazepine was finally stopped successfully after seven years. Ten years later, Elsa is the mother of two young children and is able to take care of them. She has never had a relapse of her psychotic disorder or catatonic state. DISCUSSION: The etiopathogenic diagnosis is problematic. Some indices in the familial history may suggest a traumatic event. But one to the total residual amnesia it was never confirmed, and traumatic catatonia are extremely rare. Normal CPK levels, with autonomic disturbance limited to tachycardia and the lack of resolution after discontinuance of medication, argues against a diagnosis of neuroleptic malignant syndrome (NMS). But CPK levels are non specific, and NMS without pyrexia has been described. The occurrence of the catatonic syndrome 21 days after the first dose of a neuroleptic could be diagnostic. This case involved a non organic catatonic psychosis followed by neuroleptic induced catatonia. Catatonia is described as a risk factor for the development of NMS and some consider NMS to be a variant of malignant catatonia. The interest of this report is (1) it reinforces the need to be cautious before prescribing neuroleptics in adolescents presenting with symptoms of catatonia; (2) the complete recovery from catatonia after treatment with intensive care and more than three weeks of intravenous clonazepam without the use of ECT and (3) the effectiveness of carbamazepine over a long period of follow-up. Although trials on carbamazepine in catatonia are published, there are no data available for the control of residual symptoms or the long term prognosis, especially in child and adolescent psychiatry.

Relationship between impulsivity and platelet serotonin content in adolescents.

The relationship between impulsivity and serotonin function was explored in impulsive and non-depressed adolescents. Platelet serotonin content was chosen as a peripheral indicator of central serotonin function. Impulsivity was assessed with a questionnaire. All measures were performed once a week over a 6-week period for all subjects. Subjects comprised eight adolescent inpatients who were hospitalized as a result of their impulsive acts and eight healthy age- and sex-matched control subjects. Mean platelet serotonin concentration was significantly higher in the impulsive group than in the control group. Platelet serotonin concentration was positively correlated with the intensity of impulsivity in the patient group.

Whole blood serotonin content, tryptophan concentrations, and impulsivity in anorexia nervosa.

BACKGROUND: We hypothesized that anorectics with or without bulimic features would differ on impulsivity and indices of central serotoninergic function (high impulsivity being correlated with reduced serotoninergic function). METHODS: For all patients impulsivity rating scales and questionnaires detailing severity of eating disorder were assessed, and whole blood serotonin concentration (5-HT), free and total tryptophan (TT) concentrations, and large neutral amino acids (LNAA) were assayed. RESULTS: Nineteen patients with anorexia nervosa were included, 10 presented associated bulimic features and nine did not. Twelve healthy matched controls were also included. Our hypothesis was not verified. However, tryptophan concentration and the ratio of tryptophan concentration to LNAA allow us to separate controls from anorectics, whereas 5-HT concentration does not. Two significant and positive correlations were found: between impulsivity and anxiety in the total anorectic population, and between anxiety and serotonin in the impulsive group. CONCLUSIONS: All measured peripheral biologic indices except 5-HT concentration may be of interest in this pathology. Impulsivity and anxiety seem to be two personality components involved in anorexia nervosa. This study lead us to the necessity of redefining impulsivity in anorexia nervosa.

Tryptophanemia and tyrosinemia in adolescents with impulsive behavior.

Tryptophan (TRP) and tyrosine (TYR), respectively the circulating precursors of the central serotonergic (5-HT) and catecholamine systems, were measured in eight adolescents with impulsive behavior regardless of the exact type of disorder. The 6 week study period included weekly blood sampling and clinical evaluation. The ratios of TRP and TYR to large neutral amino acids (LNAA), which indicate the availability for the synthesis of neurotransmitters, were calculated. Comparison of results with eight hospitalized controls of the same age (12.5 to 18 years) revealed lower total TRP levels in four adolescent patients, a lower TRP/LNAA ratio in three adolescents, and a lower free TRP concentration in six adolescents with discretely enhanced albuminemia. A slight increase in TYR and the TYR/LNAA ratio was noted in nearly all of the adolescent patients. Despite the heterogeneity of individual biological results, the impulsive behavior subjects in this study seemed to present abnormalities in neurotransmitter precursors.