Dysbindin (DTNBP1, 6p22.3) is Associated with Childhood-Onset Psychosis and Endophenotypes Measured by the Premorbid Adjustment Scale (PAS)

Straub et al. (2002) recently identified the 6p22.3 gene dysbindin (DTNBP1) through positional cloning as a schizophrenia susceptibility gene. We studied a rare cohort of 102 children with onset of psychosis before age 13. Standardized ratings of early development, medication response, neuropsychological and cognitive performance, premorbid dysfunction and clinical follow-up were obtained. Fourteen SNPs were genotyped in the gene DTNBP1. Family-based pairwise and haplotype transmission disequilibrium test (TDT) analysis with the clinical phenotype, and quantitative transmission disequilibrium test (QTDT) explored endophenotype relationships. One SNP was associated with diagnosis (TDT p=.01). The QTDT analyses showed several significant relationships. Four adjacent SNPs were associated (p values=.0009-.003) with poor premorbid functioning. These findings support the hypothesis that this and other schizophrenia susceptibility genes contribute to early neurodevelopmental impairment.

IQ stabilization in childhood-onset schizophrenia

OBJECTIVE

To examine the long term IQ trajectory for childhood-onset schizophrenia (COS) in an expanded, prospective longitudinal study.

METHODS

Seventy children meeting DSM criteria for schizophrenia were tested at 2 year intervals with age appropriate Wechsler intelligence tests and repeated administration of information and comprehension WISC subtests even after age 18. For a subgroup with 31 patients, pre-NIH IQ test administrations were available including 18 pre-psychotic and 13 post-psychotic subjects. The pattern of IQ performance over time was determined using mixed model regression analysis.

RESULTS

No progressive cognitive decline was seen up to 13+ years post psychosis onset. For the subgroup of subjects with pre-illness scores, there had been an initial steep decline in IQ, from about 2 years prior to 1.7 years after onset of psychotic symptoms, as reported for adult patients.

CONCLUSIONS

The level long-term trajectory of IQ measures in COS appears stable, similar to that reported for adult onset patients. For COS, level cognitive functioning extends up to 13+ years post psychosis onset, in spite of chronic illness and concomitant, progressive loss of cortical gray matter.

Lack of evidence for elevated obstetric complications in childhood onset schizophrenia

BACKGROUND

Pre-, peri-, and postnatal obstetric complications (OC) are reported to be more frequent in adult patients with schizophrenia and have been linked to both greater severity and to "earlier" age of onset (before either age 18 or 22) in studies of adult patients. We hypothesized that by extrapolation, patients with childhood-onset schizophrenia (COS), with very early onset and very severe illness, would have had more numerous or more salient OC compared with their healthy siblings.

METHODS

We compared the obstetric records of 60 COS children and 48 healthy siblings using the Columbia Obstetrics Complication Scale, a comprehensive measurement scale consisting of 37 variables having included a separate scale for fetal hypoxia.

RESULTS

Patients with COS did not have a higher incidence of OC than the healthy sibling control group with the exception of increased incidence of maternal vomiting.

CONCLUSIONS

Obstetric complications, with the possible exception of maternal vomiting, are unlikely to play a major role in the etiopathogenesis of childhood-onset schizophrenia.

Multidimensionally impaired: the good news

INTRODUCTION

Long-term outcomes in children with atypical psychosis have been poorly studied. Four to 6 weeks of inpatient observation and up to 11 years (mean, 4.0 +/- 1.3 years) of follow- up have afforded us some experience with this probably heterogeneous group of transiently psychotic patients commonly mislabeled as schizophrenic. Despite severe preadmission morbidity, some patients have successfully remained neuroleptic-free since discharge. Predictors of good versus poor outcome were sought.

METHODS

Of roughly 150 patients admitted with the presumptive diagnosis of schizophrenia, 32 patients were discharged meeting criteria for psychosis not otherwise specified (NOS), otherwise labeled by the NIMH team as "multidimensionally impaired" (MDI). Admission and biannual follow-up data included a semistructured clinical interview with the Schedule for Affective Disorders and Schizophrenia for School Age Children (K-SADS), IQ testing, clinical rating scales (e.g., Clinical Global Impression Scale (CGI), Children's Global Assessment Scale (C-GAS), Brief Psychiatric Rating Scale (BPRS), Scales for the Assessment Negative and Positive Symptoms (SANS and SAPS), and Bunney-Hamburg (B-H)). At follow-up (as of February 2005) 38% of patients (12 of 32) met criteria for bipolar 1 disorder, 12% (4 of 23) for major depressive disorder (MDD), and 3% (1 of 32) for schizoaffective disorder. The remaining 47% of patients (15 of 32) were divided into two groups on the basis of whether they were in remission and neuroleptic-free ("good outcome," n = 5) or still severely impaired and/or psychotic regardless of pharmacotherapy ("poor outcome," n = 10) at follow-up.

RESULTS

Good-outcome patients had a significantly higher baseline level of functioning (on admission and on medications). This was demonstrated by better scores on CGI (3.5 +/- 0.6 versus 4.8 +/- 0.8; p = 0.03) and C-GAS (66.3 +/- 6.3 versus 38.6 +/- 11.5; p = 0.01). Groups were otherwise comparable in demographic data (gender, race, socioeconomic status, age at onset), months of neuroleptic exposure, severity of psychotic symptoms, and level of premorbid functioning.

CONCLUSION

C-GAS (which correctly classified 85.7% of good-outcome subjects) and CGI at baseline appear to predict outcome. On other variables, MDI subgroups were remarkably similar.

GAD1 (2q31.1), which encodes glutamic acid decarboxylase (GAD67), is associated with childhood-onset schizophrenia and cortical gray matter volume loss

Postmortem brain studies have shown deficits in the cortical gamma-aminobutyric acid (GABA) system in schizophrenic individuals. Expression studies have shown a decrease in the major GABA-synthesizing enzyme (glutamic acid decarboxylase (GAD67) mRNA levels in neurons in dorsolateral prefrontal cortex in schizophrenics relative to controls. In the present study, SNPs in and around the GAD1 gene, which encodes the protein GAD67, were tested on a rare, severely ill group of children and adolescents with childhood-onset schizophrenia (COS) (n=72), in a family-based association analysis. Compared to adult-onset samples, the COS sample has evidence for more salient familial, and perhaps genetic, risk factors for schizophrenia, as well as evidence for frontal cortical hypofunction, and greater decline in cortical gray matter volume on anatomic brain MRI scans during adolescence. We performed family-based TDT and haplotype association analyses of the clinical phenotype, as well as association analyses with endophenotypes using the QTDT program. Three adjacent SNPs in the 5' upstream region of GAD1 showed a positive pairwise association with illness in these families (P=0.022-0.057). Significant transmission distortion of 4-SNP haplotypes was also observed (P=0.003-0.008). Quantitative trait TDT analyses showed an intriguing association between several SNPs and increased rate of frontal gray matter loss. These observations, when taken together with the positive results reported recently in two independent adult-onset schizophrenia pedigree samples, suggest that the gene encoding GAD67 may be a common risk factor for schizophrenia.

Childhood-onset schizophrenia: smooth pursuit eye-tracking dysfunction in family members

BACKGROUND

Childhood-onset schizophrenia (COS), a severe form of the disorder, is of interest for etiologic studies. Smooth pursuit eye-tracking dysfunction (ETD) is a biological marker for schizophrenia.

AIMS

To compare familial eye-tracking abnormalities for COS and adult-onset schizophrenia (AOS).

METHOD

Eye-tracking performance for 70 COS parents, 64 AOS parents and 20 COS siblings was compared to their respective age-matched control groups.

RESULTS

COS and AOS parents had higher rate of dichotomously rated eye-tracking dysfunction than their respective controls (16% vs. 1% and 22% vs. 4%, respectively). COS parents and siblings also differed from controls on several continuous measures. However, scores for COS, AOS and control groups overlapped extensively.

CONCLUSIONS

Genetic factors underlying eye-tracking dysfunction appear more salient for COS. However, eye-tracking measures have to be used with caution for endophenotypic definition due to low predictive power.

DECLARATION OF INTEREST

The study was done at the National Institutes of Health.

Childhood onset schizophrenia: familial neurocognitive measures

OBJECTIVE

Early onset disorders may have more salient familial/genetic etiology. Neurocognitive deficits which are seen in families of adult onset schizophrenic patients were examined in healthy family members of patients with childhood-onset schizophrenia (COS).

METHODS

Trail Making Tests (TMT) A and B, Wechsler Intelligence Scale-Revised Digit Span and Vocabulary subtests were administered to 67 parents and 24 siblings of patients with childhood-onset schizophrenia and 114 healthy community controls (CC) comparable in sex, age, and educational level.

RESULTS

COS siblings performed significantly more poorly than did controls on Trails Making Test B with a trend for poorer performance evident on Trails Making Test A. COS parents performed more poorly than controls only on Trails Making Test A.

CONCLUSIONS

Healthy first-degree relatives of COS probands have subtle deficits in tests involving oculomotor/psychomotor speed, working memory and executive function. This provides further support for continuity between COS and later onset schizophrenia and for a familial/genetic factor associated with the illness.

Looking for childhood schizophrenia: case series of false positives

Extensive experience with the diagnosis of childhood-onset schizophrenia indicates a high rate of false positives. Most mislabeled patients have chronic disabling, affective, or behavioral disorders. The authors report the cases of three children who passed stringent initial childhood-onset schizophrenia "screens" but had no chronic psychotic disorder. For two, the European literature yielded more fitting diagnoses: psychosis not otherwise specified (e.g., reactive or psychogenic psychosis, paranoid schizophrenia), single episode in full remission (e.g., anxiety psychosis), and factitious disorder (DSM-IV 300.16). These cases illustrate that transient psychotic illnesses can be misdiagnosed as childhood-onset schizophrenia. Proper identification can prevent years of inappropriate therapies.

Comparison of progressive cortical gray matter loss in childhood-onset schizophrenia with that in childhood-onset atypical psychoses

BACKGROUND

Recent anatomical brain magnetic resonance imaging (MRI) studies show a striking postpsychotic progressive loss of cortical gray matter (GM) in patients with childhood-onset schizophrenia (COS), which appears greater than that seen for adult patients. However, the diagnostic specificity and the relationship of these changes to drug treatment and cognitive functioning remain unclear. We performed a comparative prospective brain MRI study in patients with COS and pediatric patients with transient psychosis with behavior problems (psychosis not otherwise specified) provisionally considered multidimensionally impaired (MDI). We hypothesized that cortical GM loss would occur in patients with COS but not in adolescents with atypical psychoses.

METHODS

Anatomical brain MRI was performed at baseline and follow-up in 19 patients in the MDI group (mean [SD] age of 13.3 [3.1] years); in 23 patients with COS matched for age, sex, IQ score, and drug treatment (mean [SD] age of 13.9 [2.5] years); and 38 healthy control subjects matched for age and sex (mean [SD] age of 13.3 [3.1] years). The mean (SD) follow-up was 2.5 (0.8) years. Volumes of the cerebrum and total and regional GM were obtained by using automated analysis, and percent change in volume across time was calculated. One-way analyses of variance with post hoc Tukey Honestly Significantly Different comparisons were performed to examine group differences in the percent change in GM across follow-up.

RESULTS

The COS group had significantly greater total, frontal, temporal, and parietal GM loss than did the MDI or healthy control groups; analysis of variance post hoc P values ranged from.03 to.001. The MDI and control groups did not differ significantly from each other.

CONCLUSIONS

The cortical GM volume loss in COS appears diagnostically specific; it was not seen in children and adolescents with atypical psychosis. Because both patient groups had similar early developmental patterns, cognitive functioning, medications, and hospitalizations, this progressive loss appears to be intrinsic to COS. An ongoing neurodevelopmental process and/or brain response specific to the illness could account for these changes.

Clozapine-induced neutropenia in children: management with lithium carbonate

Clozapine, an atypical antipsychotic, is the most effective medication for treatment-resistant schizophrenia, but its use is limited by the high risk of neutropenia and agranulocytosis. In children, the rate of clozapine-induced neutropenia is even higher than in adults. We report two cases of children 7- and 12-years old diagnosed with very early onset schizophrenia, who developed neutropenia when treated with clozapine. In both cases addition of lithium carbonate elevated the white blood count (WBC) allowing clozapine rechallenge. WBC and total neutrophil count remained stable long-term with coadministration of clozapine (400-425 mg per day) and lithium with the blood level of 0.8-1.1 microg/mL. This report supports the use of adjunct lithium for clozapine-induced neutropenia as a safe and successful strategy in children.

Clozapine-induced akathisia in children with schizophrenia

Akathisia is a relatively rare side effect with the newer atypical antipsychotic agents, particularly clozapine, and is easily misdiagnosed in children. As children are often unable to describe their symptoms verbally, their akathisia can be misdiagnosed as worsening of their psychosis, prompting an unnecessary increase in their neuroleptic dose. Two cases of childhood-onset schizophrenia associated with clozapine-induced akathisia responsive to beta-blocker treatment are described. Akathisia should be considered in all cases of apparent nonresponse to atypical antipsychotics.

Structural brain MRI abnormalities in healthy siblings of patients with childhood-onset schizophrenia

OBJECTIVE

Childhood-onset schizophrenia shows progressive brain magnetic resonance imaging (MRI) changes during adolescence, which follow a back-to-front "wave." The authors' goal was to examine whether healthy siblings of patients with childhood-onset schizophrenia show structural brain abnormalities and the age-related pattern of abnormalities seen in patients with childhood-onset schizophrenia.

METHOD

Anatomic brain MRI scans were obtained from 15 psychiatrically healthy full siblings of 15 patients with childhood-onset schizophrenia and from 32 matched community volunteers. Automated measures were used to compare total and regional brain volumes of the siblings and volunteers.

RESULTS

Siblings of patients with childhood-onset schizophrenia had smaller total cerebral volume and total, frontal, and parietal gray matter volumes than volunteers. When divided into younger and older groups, younger siblings had smaller parietal gray matter volumes and older siblings showed trends for smaller total and frontal gray matter volumes.

CONCLUSIONS

Healthy siblings of patients with childhood-onset schizophrenia share brain MRI abnormalities with the patients that may follow a similar pattern of progression. Developmental brain abnormalities in childhood-onset schizophrenia may thus be genetic trait markers.

Correlation of antipsychotic and prolactin concentrations in children and adolescents acutely treated with haloperidol, clozapine, or olanzapine

Patients with a Diagnostic and Statistical Manual of Mental Disorders (third edition, revised) diagnosis of schizophrenia or psychotic disorder not otherwise specified with onset of psychosis before the age of 13 participated in 6- to 8-week open or double-blind trials of haloperidol (n = 15, mean dose 15.4 +/- 8.1 mg/day [0.27 +/- 0.15 mg/kg/day]), clozapine (n = 30, mean dose 269.9 +/- 173.3 mg/day [4.4 +/- 2.6 mg/kg/day]), or olanzapine (n = 12, mean dose 17.5 +/- 2.8 mg/day [0.30 +/- 0.13 mg/kg/day]). Blood samples were obtained at 6 weeks for evaluation of haloperidol, reduced haloperidol, clozapine, desmethylclozapine, and olanzapine plasma concentrations and serum prolactin concentrations. No gender differences were noted for antipsychotic dose or concentration within each treatment group. Correlations between antipsychotic plasma concentration and serum prolactin concentration were significant only for the olanzapine treatment group (r = 0.80, p = 0.002). Separate correlations for gender were significant only for females receiving olanzapine (r = 0.91, p = 0.03); the patient with the highest serum prolactin experienced galactorrhea. Further studies evaluating the prolactin-elevating properties of antipsychotics are warranted in this population.

Smooth pursuit eye-tracking impairment in childhood-onset psychotic disorders

OBJECTIVE

Although childhood-onset schizophrenia is relatively rare, a sizable group of children with severe emotional disturbances have transient psychotic symptoms that fall outside of current syndrome boundaries. The relationship of this group of children to those with childhood-onset schizophrenia and other childhood psychiatric disorders is unclear. In this study, the authors compared smooth pursuit eye tracking, a biological trait marker associated with schizophrenia, of children and adolescents with psychotic disorder not otherwise specified to that of children with childhood-onset schizophrenia and healthy comparison subjects.

METHOD

By means of infrared oculography, smooth pursuit eye movements during a 17 degrees /second visual pursuit task were quantitatively and qualitatively compared in 55 young adolescents (29 with childhood-onset schizophrenia and 26 with psychotic disorder not otherwise specified) and their respective independent healthy comparison groups (a total of 38 healthy subjects).

RESULTS

Subjects with childhood-onset schizophrenia had qualitatively poorer eye tracking, higher root mean square error, lower gain, and a greater frequency of catch-up saccades than healthy children. Subjects with psychotic disorder not otherwise specified also had qualitatively poorer eye tracking, higher root mean square error, and lower gain than healthy children, but saccade frequency did not differ significantly.

CONCLUSIONS

Children with childhood-onset schizophrenia exhibit a pattern of eye-tracking dysfunction similar to that reported for adult patients. Similar abnormalities were seen in the subjects with psychotic disorder not otherwise specified except that they did not exhibit a greater frequency of catch-up saccades. Prospective longitudinal neurobiological and clinical follow-up studies of both groups are currently underway to further validate the distinction between these two disorders. Also, family studies are planned to establish whether eye-tracking dysfunction represents a trait- or state-related phenomenon in subjects with psychotic disorder not otherwise specified.

Metabolic acidosis induced by acetazolamide

The carbonic anhydrase inhibitors that are used most frequently in ophthalmic practice are acetazolamide and methazolamide. They both are weak systemic diuretics and lower intraocular pressure ultimately by decreasing aqueous production. Unfortunately, they have a number of important side effects including the potentiation or exacerbation of metabolic acidosis. In some patients, this pH shift may be quite transient and temporary; whereas, in some patients with other maladies, the acidosis may be much more serious. The patient herein reported had chronic obstructive pulmonary disease and had had a nephrectomy. Close patient monitoring is advisable in these types of patients.

Ectopia lentis secondary to physical abuse in a traumatized, elderly individual

The proper diagnosis of ocular emergencies is usually straightforward since the patient generally can communicate the nature and circumstances of the injury. However, the mental status of the patient occasionally may seriously complicate obtaining an accurate history of the trauma. This may be particularly important when the patient has been physically abused by a relative. Ectopia lentis is a possible consequence of trauma. The elderly patient herein presented suffered ectopia lentis and had evidence of other systemic trauma. The proper management of a patient of this type will be discussed.

An analysis of contact lens enzyme cleaners

Currently, in the United States, the Food and Drug Administration has approved a number of enzyme cleaners for use with soft contact lenses. These cleaners contain three active enzymes--papain, pancreatin, and subtilisin. Although several studies have compared the cleaning efficacy of papain and pancreatin, little information exists concerning subtilisin. It was the aim of this investigation to compare the performances of four marketed enzyme cleaners, including Allergan Enzymatic (papain), Optizyme (pancreatin), ReNu Effervescent (subtilisin), and Ultrazyme (subtilisin A). Lenses were examined using the scanning electron microscope, and the amount of deposits on the lens surfaces quantified by digital analysis. All of the enzyme cleaners were effective in removing deposits from the contact lenses surfaces, but there was no significant difference in the cleaning efficacy of the four cleaners tested.