Variant-specific changes in RAC3 function disrupt corticogenesis in neurodevelopmental phenotypes.

Variants in RAC3, encoding a small GTPase RAC3 which is critical for the regulation of actin cytoskeleton and intracellular signal transduction, are associated with a rare neurodevelopmental disorder with structural brain anomalies and facial dysmorphism. We investigated a cohort of 10 unrelated participants presenting with global psychomotor delay, hypotonia, behavioural disturbances, stereotyped movements, dysmorphic features, seizures and musculoskeletal abnormalities. MRI of brain revealed a complex pattern of variable brain malformations, including callosal abnormalities, white matter thinning, grey matter heterotopia, polymicrogyria/dysgyria, brainstem anomalies and cerebellar dysplasia. These patients harboured eight distinct de novo RAC3 variants, including six novel variants (NM_005052.3): c.34G > C p.G12R, c.179G > A p.G60D, c.186_188delGGA p.E62del, c.187G > A p.D63N, c.191A > G p.Y64C and c.348G > C p.K116N. We then examined the pathophysiological significance of these novel and previously reported pathogenic variants p.P29L, p.P34R, p.A59G, p.Q61L and p.E62K. In vitro analyses revealed that all tested RAC3 variants were biochemically and biologically active to variable extent, and exhibited a spectrum of different affinities to downstream effectors including p21-activated kinase 1. We then focused on the four variants p.Q61L, p.E62del, p.D63N and p.Y64C in the Switch II region, which is essential for the biochemical activity of small GTPases and also a variation hot spot common to other Rho family genes, RAC1 and CDC42. Acute expression of the four variants in embryonic mouse brain using in utero electroporation caused defects in cortical neuron morphology and migration ending up with cluster formation during corticogenesis. Notably, defective migration by p.E62del, p.D63N and p.Y64C were rescued by a dominant negative version of p21-activated kinase 1. Our results indicate that RAC3 variants result in morphological and functional defects in cortical neurons during brain development through variant-specific mechanisms, eventually leading to heterogeneous neurodevelopmental phenotypes.

Structural brain anomalies in patients with FOXG1 syndrome and in Foxg1+/- mice.

OBJECTIVE: FOXG1 syndrome is a rare neurodevelopmental disorder associated with heterozygous FOXG1 variants or chromosomal microaberrations in 14q12. The study aimed at assessing the scope of structural cerebral anomalies revealed by neuroimaging to delineate the genotype and neuroimaging phenotype associations. METHODS: We compiled 34 patients with a heterozygous (likely) pathogenic FOXG1 variant. Qualitative assessment of cerebral anomalies was performed by standardized re-analysis of all 34 MRI data sets. Statistical analysis of genetic, clinical and neuroimaging data were performed. We quantified clinical and neuroimaging phenotypes using severity scores. Telencephalic phenotypes of adult Foxg1+/- mice were examined using immunohistological stainings followed by quantitative evaluation of structural anomalies. RESULTS: Characteristic neuroimaging features included corpus callosum anomalies (82%), thickening of the fornix (74%), simplified gyral pattern (56%), enlargement of inner CSF spaces (44%), hypoplasia of basal ganglia (38%), and hypoplasia of frontal lobes (29%). We observed a marked, filiform thinning of the rostrum as recurrent highly typical pattern of corpus callosum anomaly in combination with distinct thickening of the fornix as a characteristic feature. Thickening of the fornices was not reported previously in FOXG1 syndrome. Simplified gyral pattern occurred significantly more frequently in patients with early truncating variants. Higher clinical severity scores were significantly associated with higher neuroimaging severity scores. Modeling of Foxg1 heterozygosity in mouse brain recapitulated the associated abnormal cerebral morphology phenotypes, including the striking enlargement of the fornix. INTERPRETATION: Combination of specific corpus callosum anomalies with simplified gyral pattern and hyperplasia of the fornices is highly characteristic for FOXG1 syndrome.

Acute Flaccid Myelitis in German Children in 2016-the Return of Polio?

BACKGROUND: Although poliomyelitis has almost been eradicated worldwide, cases of a polio-like disease with asymmetrical flaccid paralysis of variable severity have been seen repeatedly in recent years. METHODS: Data were collected on children treated in hospitals in the German federal states of Bavaria and Lower Saxony in 2016. The frequency of disease across Germany was estimated on the basis of voluntary reporting to the Robert Koch Institute. 16 cases were registered there for the entire year 2016. RESULTS: 7 children with flaccid paralysis of acute onset were treated in the participating hospitals in the summer and fall of 2016. We describe two illustrative cases, one with a mild course and one with a severe course. Rapid diagnosis requires not only clinical neurological assessment but also neurophysiological studies, magnetic resonance imaging (MRI), and targeted microbiological testing. The characteristic features include damage to the anterior horn of the spinal cord that can be seen on MRI and/or electrophysiologically demonstrable abnormalities indicating motor neuron damage. A pathogen can hardly ever be identified in the cerebrospinal fluid, but the epidemiological context and the detection of viruses in the stool or respiratory secretions indicate that entero - viruses may be responsible. CONCLUSION: The prognosis of this disease cannot be reliably assessed at first, and no specific treatment is currently available.

Rasmussen encephalitis: incidence and course under randomized therapy with tacrolimus or intravenous immunoglobulins.

PURPOSE: Rasmussen encephalitis (RE) leads to progressive tissue and function loss of one brain hemisphere and often intractable epilepsy. This is the first randomized prospective treatment trial in RE. METHODS: Germany-wide, patients with suspected recent-onset RE were recruited and if eligible randomized to tacrolimus or intravenous immunoglobulins (IVIGs). A loss of motor function or hemispheric volume by ≥ 15% (in patients >12 years at disease onset: ≥ 8%) led to study exit. Untreated patients served as a historical control group. KEY FINDINGS: Over 6.3 years, 21 patients with recent-onset RE were identified. Sixteen were randomized to tacrolimus (n = 9) or IVIG (n = 7). Immunotreated patients had a longer "survival" than the historical controls. Neither treatment was more efficacious than the other. Two tacrolimus patients experienced serious adverse events. No immunotreated but several untreated patients developed intractable epilepsy. No patient with refractory epilepsy became treatment-responsive under immunotherapy. SIGNIFICANCE: The countrywide incidence rate of diagnosed RE is estimated as 2.4 cases/107 people ≤ age 18/year. Treatment with tacrolimus or IVIG may slow down tissue and function loss and prevent development of intractable epilepsy. However, immunotherapy may "arrest" patients in a dilemma state of pharmacoresistant epilepsy but too good function to be offered functional hemispherectomy. These compounds may therefore contribute to the therapeutic armamentarium for RE patients without difficult-to-treat epilepsies.

Morbidity and Mortality conference as part of PDCA cycle to decrease anastomotic failure in colorectal surgery.

BACKGROUND AND AIMS: Morbidity and Mortality meetings are an accepted tool for quality management in many hospitals. However, it is not proven whether these meetings increase quality. It was the aim of this study to investigate whether Morbidity and Mortality meetings as part of a PDCA cycle (Plan, Do, Check, Act) can improve the rate of anastomotic failure in colorectal surgery. MATERIALS AND METHODS: From January 1, 2004, to December 31, 2009, data for all anastomotic failures in patients operated on for colorectal diseases in the Department of Surgery (Klinikum Friedrichshafen, Germany) were prospectively collected. The events were discussed in Morbidity and Mortality meetings. On the basis of these discussions, a strategy to prevent anastomotic leaks and a new target were defined (i.e. 'Plan'). This strategy was implemented in the following period (i.e. 'Do') and results were prospectively analysed. A new strategy was established when the results differed from the target, and a new standard was defined when the target was achieved (i.e. 'Check, Act'). RESULTS: The year 2004 was set as the base year. In 2005 and 2006, new strategies were established. Comparing this period with the period of strategy conversion (2007-2009), we found a significant decrease in the anastomotic failure rate in colorectal surgery patients (5.7% vs 2.8%; p = 0.05), whereas the risk factors for anastomotic failure were unchanged or unfavourable. CONCLUSIONS: If Morbidity and Mortality meetings are integrated in a PDCA cycle, they can decrease anastomotic failure rates and improve quality of care in colorectal surgery. Therefore, the management tool 'PDCA cycle' should be considered also for medical issues.

Comparison of three clinical rating scales in Friedreich ataxia (FRDA).

To test the validity and reliability of the scale for the assessment and rating of ataxia (SARA) in Friedreich ataxia (FRDA). SARA is limited to eight items and can be performed rapidly. Ninety-six patients with a molecular genetic diagnosis of FRDA were rated using three different clinical scales, the FRDA Rating Scale (FARS), the International Cooperative Ataxia Rating Scale (ICARS), and SARA. Despite considerable discrepancies in scale size and subscale structure, SARA total scores were significantly correlated with ICARS (r = 0.953, P < 0.0001) and FARS (r = 0.938, P < 0.0001) total scores. SARA total scores also correlated with the activities of daily living (ADL, r = 0.929, P < 0.0001). Although originally developed for the use in dominantly inherited ataxias, which are primarily ataxias of the cerebellar type, SARA can also be used successfully to assess afferent ataxia, which is the predominant form in FRDA. Because SARA is characterized by high interrater reliability and practicability, SARA is applicable and well suited forclinical trials of FRDA.

Microstructural callosal abnormalities in normal-appearing brain of children with developmental delay detected with diffusion tensor imaging.

Callosal fibres play an important role in psychomotor and cognitive functions. The purpose of this study was to investigate possible microstructural abnormalities of the corpus callosum in children with developmental delay, who have normal conventional brain MR imaging results. Seventeen pediatric patients (aged 1-9 years) with developmental delay were studied. Quantitative T2 and fractional anisotropy (FA) values were measured at the genu and splenium of the corpus callosum (CC). Fibre tracking, volumetric determination, as well as fibre density calculations of the CC were also carried out. The results were compared with those of the age-matched healthy subjects. A general elevation of T2 relaxation times (105 ms in patients vs. 95 ms in controls) and reduction of the FA values (0.66 in patients vs. 0.74 in controls) at the genu of the CC were found in patients. Reductions of the fibre numbers (5,464 in patients vs. 8,886 in controls) and volumes (3,415 ml in patients vs. 5,235 ml in controls) of the CC were found only in patients older than 5 years. The study indicates that despite their inconspicuous findings in conventional MRI microstructural brain abnormalities are evident in these pediatric patients suffering from developmental delay.

Does proximal myotonic myopathy show anticipation?

Proximal myotonic myopathy (DM2, PROMM) has not been reported in patients younger than 18 years, and apparent lack of congenital and childhood forms is thought to be one of the distinctive clinical characteristics of this trait. We now describe a 2-year-old boy, the youngest member of a family with a history for myotonia in 2 generations. The patient's 35-year-old mother was diagnosed with DM2 of late juvenile onset. She developed aggravating myotonic symptoms during pregnancy. Remarkably few intrauterine child movements were noticed. After birth the child showed general muscular hypotonia with delayed statomotoric development (sitting and crawling at 13 months, first lifting into standing position at 18 months). Muscle reflexes were normal. In the CL3N58 region of ZNF9, DM2-typical unstable expanded CCTG arrays of about 14.5 kb (about 2,500 repeats) were detected both in the mother and the patient by Southern blotting. Expansion of the DM1-specific DMPK CTG repeat was excluded.

A semiological classification of status epilepticus.

The classification of status epilepticus (SE) has been a subject of discussion for many years, yet no satisfactory agreement has been reached. Due to their complexity, status episodes often defy classification according to the current international classification scheme. The semiological seizure classification (SSC) has been in use in several epilepsy centers for more than a decade, and has proven to be a valid approach to the classification of epileptic seizures. Based on the detailed analysis of more than 100 episodes of SE documented with video-EEG recordings, the authors now present a proposal for a semiological classification of status epilepticus (SCSE). The SCSE reflects the assumption implied by all modern definitions of SE that "there are as many types of status as there are types of seizures" and relies on the same principles as the SSC, focusing on the main clinical manifestations and the evolution of the status episode. The clinical manifestations of SE are subdivided into semiological components and classified along three axes: the type of brain function predominantly compromised by the seizure activity, the body part involved, and the evolution over time. Each axis contains several subcategories, so that many different levels of accuracy are possible. The SCSE, just like the SSC, is meant to be part of a comprehensive epilepsy classification which classifies as independent variables (epileptogenic zone, ictal semiology, etiology, related medical conditions) the main features of the patient's epilepsy, allowing for each variable maximum flexibility.

Functional organization of the brain with malformations of cortical development.

We examined the localization of cerebral functions in 28 patients with focal epilepsy and malformations of cortical development (MCDs). Polymicrogyria occurred in nine, hemimegalencephaly in four, heterotopia in eight, and focal cortical dysplasia (FCD) in nine cases. We used simple (sensomotor, visual) or complex (language, memory) functional magnetic resonance imaging (fMRI) paradigms. Two thirds of MCDs were activated by simple fMRI paradigms, whereas they less frequently showed activity during complex cognitive fMRI paradigms. During simple paradigms, all disturbances of cortical organization (polymicrogyria, schizencephaly, and mild-type FCD) showed activity, whereas other MCDs (disturbances of earlier steps of cortical development: hemimegalencephaly, Taylor-type FCD, and heterotopia) showed activity in only 44% (p < 0.01). The association between the pathophysiology and morphology of MCDs confirms the recently proposed classification system. Both focal neurological signs (p < 0.05) and focal electroencephalogram slowing (p < 0.05) independently correlated with MCD inactivity, confirming that fMRI showed neuronal functions of MCDs. Conclusively, fMRI visualizes the MCD functions and their relationship to the eloquent cortex, providing useful information before epilepsy surgery. Surgery of cortical organization disturbances should be cautiously performed because these malformations may participate to some degree in brain functions.