Severity of Cortical Thinning Correlates With Schizophrenia Spectrum Symptoms

OBJECTIVE

This study investigated the relationship between regional cortical gray matter thinning and symptoms of schizophrenia spectrum personality disorders (PDs) in siblings of patients with childhood-onset schizophrenia (COS).

METHOD

A total of 66 siblings of patients with COS were assessed for symptoms of schizophrenia spectrum PDs (avoidant, paranoid, schizoid, schizotypal). Structural magnetic resonance images were obtained at approximately 2-year intervals from the siblings and from 62 healthy volunteers matched for age, sex, ethnicity, and handedness. Cortical thickness measures were extracted. Mixed effect regression models were used to test the relationship between symptoms and cortical gray matter thickness in siblings. Cortical thinning was also tested longitudinally in healthy volunteers and siblings.

RESULTS

Cortical thinning was found to correlate with symptoms of schizotypal and, to a lesser extent, schizoid PDs. Thinning was most pronounced in the left temporal and parietal lobes and right frontal and parietal regions. Gray matter loss was found to be continuous with that measured in COS. Longitudinal thinning trajectories were found not to differ between siblings and healthy volunteers.

CONCLUSION

The present investigation of cortical thinning in siblings of patients with COS indicates that symptoms of schizophrenia spectrum PDs correlate with regional gray matter loss. This finding supports the idea of cortical thinning as a schizophrenia endophenotype.

[Replicative study of susceptibility to childhood-onset schizophrenia in Kazakhs]

This paper reports the results of replicative analysis of associations of 15 SNPs in a region of 14 genes previously identified in genome-wide association studies (GWAS) with early-onset schizophrenia in Kazakhs. An association of early-onset schizophrenia with genetic markers in three genes (VRK2, KCNB2, and CPVL) was found. An association of rs2312147 in the VRK2 gene with schizophrenia was also previously reported in the Chinese population, so this marker may be considered as possibly race-specific. Two groups consisting of four and six genes demonstrating intergenic epistatic interactions were revealed by multifactor dimensionality reduction methods. The gene ontologies of 14 studied genes were reduced to variants of one molecular function (peptidase activity) and one biological process (positive regulation of biosynthesis processes). Bioinformatic analysis of the protein-protein interactions of products of the genes under study demonstrates that the products of six out of 14 genes may be involved in a single interrelated network, the major connecting link of which is represented by their ubiquitination by the UBC protein.

Psychotic symptoms and gray matter deficits in clinical pediatric populations

BACKGROUND

Neuroanatomic studies have not yet addressed how subtle phenotypic distinctions in psychosis alter the underlying brain changes, and whether there is evidence for psychosis as a dimensional construct. We explored the relationship of cortical GM thickness to psychotic phenotypes in children.

METHODS

Cross-sectional comparison of anatomic brain imaging between patients referred as childhood-onset schizophrenia (COS) but ruled out after a drug free inpatient observation. Groups included: patients with no evidence of psychosis (n=22) after drug free observation, patients with psychosis not otherwise specified (PNOS; total n=29) further divided into those without other axis I diagnoses (n=13) and those with other axis I comorbidities (n=16), age/sex matched COS patients (n=48), and 51 matched healthy controls. GM cortical thickness was compared between the groups, and regressed on patients' SAPS, SANS and GAS scores.

RESULTS

Patients with no evidence of psychosis showed no cortical GM deficits. Presence of psychosis (PNOS with or without co-morbidities) showed some areas of temporal and prefrontal deficits, more subtle compared to the extensive bilateral cortical deficits seen for COS. GAS SAPS and SANS scores showed a relationship with cortical GM thickness although it did not survive adjustment for multiple comparisons.

CONCLUSIONS

These results highlight the need for careful phenotypic characterization, as subtle diagnostic distinctions appear to reflect distinct underlying patterns of brain deficits. The incremental nature of cortical deficits from no psychosis to PNOS to COS may further support dimensional model for psychosis.

A case report on the relationship between treatment-resistant childhood-onset schizophrenia and an abnormally enlarged cavum septum pellucidum combined with cavum vergae

The treatment of refractory schizophrenia has been a clinical challenge for most psychiatrists; the possible reasons include diagnostic errors, medical conditions and brain dysgenesis. Here, we described a patient with childhood-onset schizophrenia who had severe psychiatric symptoms such as auditory hallucinations and persecutory delusions, and etc. We reexamined all his possible medical conditions and found that the patient had an abnormally enlarged cavus septum pellucidum (CSP) combined with cavum vergae (CV) (maximum length >30 mm). Some reports suggested that abnormal CSP (length >6 mm) has a significant association with schizophrenia. However, abnormally large CSP or CSP/CV and related prognosis were reported rarely. This case suggested that abnormally enlarged CSP or CSP/CV may worsen the prognosis.

Review of neuroimaging studies of child and adolescent psychiatric disorders from the past 10 years

OBJECTIVES

To review recent neuroimaging studies of serious emotional disorders in youth and identify problems and promise of neuroimaging in clinical practice.

METHOD

Published reports from refereed journals are briefly described, critiqued, and synthesized into a summary of the findings to date.

RESULTS

Childhood-onset schizophrenia shows progressive ventricular enlargement, reduction in total brain and thalamus volume, changes in temporal lobe structures, and reductions in frontal metabolism. Autistic disorder is associated with cerebellar changes, greater total brain and lateral ventricle volume, and asymmetry. The prefrontal cortex and the basal ganglia are consistently reported as abnormal in attention-deficit/hyperactivity disorder. Patients with anorexia nervosa show enlarged CSF spaces and reductions in gray and white matter that are only partially reversible with weight recovery.

CONCLUSIONS

Results from neuroimaging studies of childhood-onset psychiatric disorders suggest consistency in the structures found to be abnormal, but inconsistencies in the nature of these abnormalities. Although neuroimaging technology holds great promise for neurodevelopmental research, it is not yet a diagnostic instrument.

Brain imaging in childhood- and adolescence-onset schizophrenia associated with obsessive-compulsive symptoms

OBJECTIVE

Childhood- and adolescence-onset schizophrenic patients with obsessive-compulsive symptoms (OCS) constitute a specific subgroup of schizophrenia. We performed magnetic resonance imaging in this group seeking evidence of neurodevelopmental insults.

METHOD

Thirty-two schizophrenic patients were compared with 19 controls. Schizophrenic subjects were divided into 15 patients with OCS (SOCS+ group; onset at 15.5 +/- 1.6 years) and 17 without OCS (SOCS- group; onset at 15.3 +/- 1.3 years). Areas of the hippocampus, frontal lobe, corpus callosum and putamen were analysed morphometrically.

RESULTS

The left hippocampus was significantly smaller in the SOCS+ group than in the SOCS- and control groups.

CONCLUSION

Reduced size of the left hippocampus in the SOCS+ group supports a neurodevelopmental etiology in this subgroup.

Lessons from childhood-onset schizophrenia

Childhood-onset schizophrenia (with an onset of psychosis by age 12) is a rare and severe form of the disorder which is clinically and neurobiologically continuous with the adult-onset disorder. Very early onset diseases provide an opportunity to look for more salient or striking risk or etiologic factors in a possibly more homogenous patient population. For the 47 patients with very early onset schizophrenia studied to date, there were more severe premorbid neurodevelopmental abnormalities, more cytogenetic anomalies, and potentially greater family histories of schizophrenia and associated spectrum disorders than later onset cases. There was no evidence for relatively increased obstetrical complications or environmental stress. These data, while preliminary, suggest a very early age of onset of schizophrenia may be secondary to greater genetic vulnerability. It is anticipated that future genetic studies of these patients may provide important etiologic information.

Common pattern of cortical pathology in childhood-onset and adult-onset schizophrenia as identified by proton magnetic resonance spectroscopic imaging

OBJECTIVE

Multislice proton magnetic resonance spectroscopic imaging (1H-MRSI) permits simultaneous acquisition and mapping of signal intensities of N-acetyl-containing compounds (mainly N-acetylaspartate, NAA), choline-containing compounds (CHO), and creatine plus phosphocreatine (CRE) from multiple whole-brain slices consisting of small single-volume elements. Previous 1H-MRSI studies of adult patients with schizophrenia showed small NAA relative signals in the hippocampal area and in the dorsolateral prefrontal cortex in comparison with healthy subjects. As part of a program to address the pathophysiological continuity between childhood-onset and adult-onset schizophrenia, the authors performed 1H-MRSI of patients with childhood-onset schizophrenia to specifically test whether the hippocampal area and dorsolateral prefrontal cortex show the same abnormalities as seen in adult-onset schizophrenia.

METHOD

A 1.5-T nuclear magnetic resonance machine was used to test 14 patients (mean age, 16.4 years) and 14 comparison subjects. Ratios of areas under the metabolite peaks of the proton spectra were determined (i.e., NAA/CRE, NAA/CHO, CHO/CRE) for multiple cortical and subcortical regions.

RESULTS

The patients showed significantly lower NAA/CRE ratios bilaterally in the hippocampal area and the dorsolateral prefrontal cortex than the comparison subjects. There were no significant differences in CHO/CRE or in NAA ratios in any other area sampled.

CONCLUSIONS

The present study shows that patients with childhood-onset schizophrenia have smaller than normal regional NAA relative signals, suggesting neuronal damage or malfunction in the hippocampal area and dorsolateral prefrontal cortex. These differences were similar in magnitude to those found in patients with adult-onset schizophrenia. The present data extend other evidence of a biological continuum between childhood- and adult-onset schizophrenia.

Frequency and severity of enlarged cavum septi pellucidi in childhood-onset schizophrenia

OBJECTIVE

Patients with schizophrenia have been reported to have a higher frequency of enlarged cavum septi pellucidi (CSP) in comparison with normal subjects. Neurodevelopmental models of schizophrenia suggest that the more severe the brain dysgenesis, the earlier the onset of psychotic symptoms. Study of patients with childhood-onset schizophrenia allows the opportunity to test this hypothesis.

METHOD

Two groups of subjects were evaluated: healthy volunteers (N=95, mean age=11.7 years) and patients with childhood-onset schizophrenia (N=24, mean age=14.6 years). Magnetic resonance images of 1-mm resampled contiguous brain slices were rated blind to diagnosis. The size of the CSP was recorded as the number of consecutive slices in which the CSP was present. Abnormal enlargement was defined as a CSP greater than 6 mm in length.

RESULTS

The frequency of an enlarged CSP was significantly higher in the patient group: 12.5% (three of 24 subjects) versus 1.1% (one of 95 subjects). Also, two of the three patients with an enlarged CSP had complete nonfusion of the septal leaflets, a more severe anomaly than was found in the one comparison subject with an enlarged CSP and typically more severe than anomalies seen in groups with adult-onset schizophrenia.

CONCLUSIONS

These findings suggest that patients with extremely early-onset (childhood) forms of schizophrenia may have more severe developmental brain anomalies than those with adult onset.

Smooth pursuit eye movements in childhood-onset schizophrenia: comparison with attention-deficit hyperactivity disorder and normal controls

Abnormalities of the smooth pursuit eye movements of adults with schizophrenia have been well described. We examined smooth pursuit eye movements in schizophrenic children, contrasting them with normal and attention-deficit hyperactivity disorder (ADHD) subjects, to determine whether there is continuity of eye movement dysfunction between childhood- and adult-onset forms of schizophrenia. Seventeen schizophrenic children with onset of illness by age 12, 18 ADHD children, and 22 normal children were studied while engaged in a smooth pursuit eye tracking task. Eye tracking variables were compared across the three groups. Schizophrenic children exhibited significantly greater smooth pursuit impairments than either normal or ADHD subjects. Within the schizophrenic group, there were no significant relationships between eye tracking variables and clinical variables, or ventricular/brain ratio. Childhood-onset schizophrenia is associated with a similar pattern of smooth pursuit abnormalities to that seen in later-onset schizophrenia.

Temporal lobe morphology in childhood-onset schizophrenia

OBJECTIVE

Neurodevelopmental models of schizophrenia imply that a more severe early brain lesion may produce earlier onset of psychotic symptoms. The medial temporal lobes have been proposed as possible locations for such a lesion. The authors tested this hypothesis in a group of children and adolescents with childhood-onset schizophrenia who had severe, chronic symptoms and who were refractory to treatment with typical neuroleptics.

METHOD

Anatomic brain magnetic resonance imaging scans were acquired with a 1.5-T scanner for 21 patients (mean age=14.6 years, SD=2.1) who had onset of schizophrenia by age 12 (mean age at onset=10.2, SD=1.5) and 41 normal children. Volumes of the temporal lobe, superior temporal gyrus, amygdala, and hippocampus were measured by manually outlining these structures on contiguous 2-mm thick coronal slices.

RESULTS

Patients with childhood-onset schizophrenia had significantly smaller cerebral volumes. With no adjustment for brain volume, no diagnostic differences were observed for any temporal lobe structure. Unexpectedly, with adjustment for total cerebral volume, larger volumes of the superior temporal gyrus and its posterior segment and a trend toward larger temporal lobe volume emerged for the patients with schizophrenia. These patients lacked the normal (right-greater-than-left) hippocampal asymmetry.

CONCLUSIONS

These findings do not indicate a more severe medial temporal lobe lesion as the basis of very early onset schizophrenia.

Neuropathological findings in a suspected case of childhood schizophrenia

The ventral tegmental area (VTA) is the major dopaminergic (DA) center responsible for the innervation of the prefrontal cortex, nucleus accumbens, and entorhinal region. These areas have been causally implicated in schizophrenia. Thus, the existence of brainstem pathology could explain many of the previously reported findings in schizophrenic (SC) patients. The authors focus on uncovering brainstem abnormalities in schizophrenia by studying the autopsied material of a patient having an early onset of symptomatology. The patient was evaluated at the age of 10 years for manneristic behavior, a speech disorder, and violence. Prominent auditory hallucinations became apparent years later. His mental status and ability for self-care steadily deteriorated until he succumbed to pneumonia at age 22. Microscopic examination of the brain showed central chromatolysis of neurons and mild gliosis in a restricted distribution of the brainstem and thalamus. Cell loss and cytoarchitectural disruption were evident in the frontal lobes, prepyriform cortex, and entorhinal region. The neuropathological changes were interpreted as a chronic derangement in the function of neurons of the rostral brainstem tegmental area and medial thalamus with secondary involvement of their terminal projection sites.

Is childhood schizophrenia a cholinergic disease? I. Muscle morphology

Four hypotonic boys (aged 4 years and 11 months, 6 years and 9 months, 7 years and 4 months, and 8 years and 10 months, respectively), all of whom demonstrated a formal thought disorder, had been psychotic for more than six months, and met the DSM-III criteria for chronic undifferentiated schizophrenia, were studied with respect to skeletal muscle morphology. A significant difference between the mean fiber diameters of type I and type II muscle fibers was observed in the three boys with the most severe thought disorder, type II muscle fibers being consistently smaller. No significant difference in the mean fiber diameter between the two fiber types were seen in the fourth boy, who was also the only one who demonstrated any secondary thought process. The boys differed in their activity levels, but there was no correlation between type II muscle fiber atrophy and hypoactivity. It is hypothesized that a depressed cholinergic system is implicated in the pathogenesis of both the muscle fiber atrophy and the formal thought disorder.

Muscle biopsy in hypotonic schizophrenic children: a preliminary report

Two hypotonic boys, aged 7 years, 3 months and 7 yers, 7 months, who possessed sufficient speech to demonstrate a severe thought disorder and who differed markedly in their activity levels, were subjected to a biopsy of the quadriceps muscle. The biopsies revealed atrophy of type 2 muscle fibers, as well as variability in the size of these fibers. The findings could be compatible with a denervation phenomenon.

Neuropathologic aspects of psychosis in children

On the basis of a search of the literature and extensive inquiries to clinicians, this paper catalogues those cases that contain any information concerning possible neuropathologic changes in cases of childhood autism or psychosis. In all, 33 cases were identified. Twenty-nine cases are from the literature; six of these are sibling pairs. Four cases were folnd by inquiry and have not been reported heretofore. Because of limitations in both the clinical and neuropathologic data in most of the case reports, the paper serves primarily as a source of reference to the 33 cases identified. The information that is available is presented along with some tentative suggestions for further research.