Rare exonic deletions implicate the synaptic organizer Gephyrin (GPHN) in risk for autism, schizophrenia and seizures.

The GPHN gene codes for gephyrin, a key scaffolding protein in the neuronal postsynaptic membrane, responsible for the clustering and localization of glycine and GABA receptors at inhibitory synapses. Gephyrin has well-established functional links with several synaptic proteins that have been implicated in genetic risk for neurodevelopmental disorders such as autism spectrum disorder (ASD), schizophrenia and epilepsy including the neuroligins (NLGN2, NLGN4), the neurexins (NRXN1, NRXN2, NRXN3) and collybistin (ARHGEF9). Moreover, temporal lobe epilepsy has been linked to abnormally spliced GPHN mRNA lacking exons encoding the G-domain of the gephyrin protein, potentially arising due to cellular stress associated with epileptogenesis such as temperature and alkalosis. Here, we present clinical and genomic characterization of six unrelated subjects, with a range of neurodevelopmental diagnoses including ASD, schizophrenia or seizures, who possess rare de novo or inherited hemizygous microdeletions overlapping exons of GPHN at chromosome 14q23.3. The region of common overlap across the deletions encompasses exons 3-5, corresponding to the G-domain of the gephyrin protein. These findings, together with previous reports of homozygous GPHN mutations in connection with autosomal recessive molybdenum cofactor deficiency, will aid in clinical genetic interpretation of the GPHN mutation spectrum. Our data also add to the accumulating evidence implicating neuronal synaptic gene products as key molecular factors underlying the etiologies of a diverse range of neurodevelopmental conditions.

Autoimmune neuropsychiatric disorders associated with streptococcal infection: Sydenham chorea, PANDAS, and PANDAS variants.

Streptococcal infection in children is usually benign and self-limited. In a small percentage of children, prominent neurologic and/or psychiatric sequelae can occur. Sydenham chorea is the best defined and best recognized. PANDAS (pediatric autoimmune neuropsychiatric disorders associated with streptococcal infection) is a well-defined syndrome in which tics (motor and/or vocal) and/or obsessive-compulsive disorder consistently exacerbate in temporal correlation to a group A beta-hemolytic streptococcal infection. PANDAS constitutes a subset of children with tics, Tourette syndrome, and obsessive-compulsive disorder. In addition to strictly defined PANDAS, we and others have recognized several PANDAS variants, including adult-onset variant, a dystonic variant, a myoclonic variant, and a "chronic" PANDAS variant. The nosology and classification of these entities are rapidly evolving. The recognition that some pediatric neurobehavioral syndromes have infectious and/or immunologic triggers points to important new avenues of disease treatment. In this review, we summarize this complex and rapidly evolving area of clinical research.

Clinical heterogeneity in familial congenital ptosis: analysis of fourteen cases in one family over five generations.

This report describes a proband and his family consisting of 14 patients affected with simple congenital ptosis. Pedigree suggests an autosomal dominant pattern with 70-90% penetrance. The family includes patients with both unilateral and bilateral involvement, and cases with and/or without complex synkinesia. Left unilateral preponderance is striking, and pedigree analysis suggests the possibility of a modifier gene determining laterality. This study represents the first report of a large family with congenital autosomal dominant simple ptosis which demonstrates the full clinical spectrum of this condition.

Anti-brain antibodies in PANDAS versus uncomplicated streptococcal infection.

The objective of this study was to assess brain involvement through the presence of antineuronal antibodies in Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcus (PANDAS) and in uncomplicated active Group A streptococcal infection. We compared serum antibrain antibody to human basal ganglia sections assessed by indirect tissue immunofluorescence in two groups: a PANDAS group, comprised of 22 patients (mean age 10.1 years; 20 male, 2 female) who met strict National Institutes of Mental Health diagnostic criteria for PANDAS and had clinically active tics or obsessive-compulsive disorder, or both; and a GABHS control group consisting of 22 patients (mean age 9.1 years; 15 mol/L, 7 female) with clinical evidence of active Group A beta-hemolytic streptococcal (GABHS) infection confirmed by throat culture and elevated antistreptolysin O titers but without history or clinical evidence of tics or obsessive-compulsive disorder. We observed positive anti-basal ganglia staining (defined as detectable staining at 1:10 serum dilution) in 14/22 patients in the PANDAS group (64%) but only 2/22 (9%) in the GABHS control group (P < 0.001, Fisher's exact test). These results suggest that antibrain antibodies are present in children with PANDAS that cannot be explained merely by a history of GABHS infection.

A new clinical feature associated with familial early-onset of dystonic-guttural tics: An unusual diagnosis of PANDAS.

Until today there is a large debate about the existence of PANDAS (pediatric autoimmune neuropsychiatric disorders associated with streptococcal infections) or PANS (pediatric acute onset neuropsychiatric syndrome). These children usually have dramatic, "overnight" onset of symptoms, including motor or vocal tics, obsessions, and/or compulsions. In addition to these symptoms, children may also have comorbid features of associated disorders. Herein, we report a family with an early onset of tics, with exclusively dystonic and guttural tics. All patients had a particularly strong excitement trigger. Two of the patients were shown to have signs suggestive of PANDAS and all family members were Group A beta-hemolytic Streptococcus (GABHS) carriers. The PANDAS spectrum is probably a group of disorders. We have described a PANDAS variant, in which the family seems to share common autoimmune pattern and may be viewed in the large spectrum of PANDAS.

Down syndrome and arterial ischemic stroke in childhood: a potential immunologic link with selective IgG4 subclass deficiency.

We report four children with Down Syndrome (DS) without evidence of congenital heart disease who sustained cerebral infarction in the context of an infectious disease. In one child, stroke occurred in the context of acute infection with Mycoplasma pneumonia. In another child, stroke occurred in the context of Streptococcus oralis (viridans subgroup) infection. In two other children, stroke occurred in the context of a bibasilar pneumonia for which an etiologic agent was not found. All patients had evidence of selective IgG4 subclass deficiency. We followed 8 other children with down syndrome with infectious diseases, but without stroke and a control group of healthy children, and measured the value of IgG4 for each group. We found a statistical significant difference of levels of IgG4 subclass deficiency in the group of stroke, in comparison with the other two groups (P values <0.001). We, therefore, suggest an association between IgG4 subclass deficiency and stroke in DS patients. IgG4 subclass deficiency could conceivably play a role in the high frequency of para-infectious related stroke in this population.

Incidence and causes of neonatal hyperbilirubinemia in a center of Catania.

AIM AND SCOPE: We conducted this study to estimate the incidence of hyperbilirubinemia in a small neonatal care unit in Catania, Italy, and to determine the underlying causes, which would be of value in identifying and implementing strategies to prevent morbidity from this condition. BACKGROUND: Management of hyperbilirubinemia remains a challenge for neonatal medicine because of the risk for serious neurological complications related to the toxicity of bilirubin. METHODS: From January 2006 to January 2007, we screened 525 newborns born at the Neonatal Care Unit of Valsalva Hospital in Catania, Italy. Infants aged 3-5 days and with unconjugated hyperbilirubinemia were included for assessment if they had a peak serum total bilirubin level exceeding 6 mg/dl (102 mumol/L). Sex, birth weight, gestational age, breast feeding, type of birth, presence of facial bruising (including cephalohematoma) and ABO group were noted. Patients with Toxoplasma or Cytomegalovirus infection, hepatic insufficiency, or suspected drug-induced hyperbilirubinemia were excluded from more detailed analysis. RESULTS: Our year-long nursery sample examined otherwise healthy-appearing term infants for the prevalence of hyperbilirubinemia (defined as bilirubin levels exceeding 6 mg/dL [11mol/L]). We found hyperbilirubinemia in 19% (100/525). Among the patients with hyperbilirubinemia, almost all (99%) had peak levels of bilirubin <20 mg/dL, levels which are generally considered to be potentially neurotoxic. CONCLUSIONS: In our clinic experience, hyperbilirubinemia was generally a serious medical issue and one whose etiology can usually be well defined.