A recurrent single-amino acid deletion (p.Glu500del) in the head domain of ß-cardiac myosin in two unrelated boys presenting with polyhydramnios, congenital axial stiffness and skeletal myopathy.

BACKGROUND: Alterations in the MYH7 gene can cause cardiac and skeletal myopathies. MYH7-related skeletal myopathies are extremely rare, and the vast majority of causal variants in the MYH7 gene are predicted to alter the rod domain of the of ß-cardiac myosin molecule, resulting in distal muscle weakness as the predominant manifestation. Here we describe two unrelated patients harboring an in-frame deletion in the MYH7 gene that is predicted to result in deletion of a single amino acid (p.Glu500del) in the head domain of ß-cardiac myosin. Both patients display an unusual skeletal myopathy phenotype with congenital axial stiffness and muscular hypertonus, but no cardiac involvement. RESULTS: Clinical data, MRI results and histopathological data were collected retrospectively in two unrelated boys (9 and 3.5 years old). Exome sequencing uncovered the same 3-bp in-frame deletion in exon 15 (c.1498_1500delGAG) of the MYH7 gene of both patients, a mutation which deletes a highly conserved glutamate residue (p.Glu500del) in the relay loop of the head domain of the ß-cardiac myosin heavy chain. The mutation occurred de novo in one patient, whereas mosaicism was detected in blood of the father of the second patient. Both boys presented with an unusual phenotype of prenatal polyhydramnios, congenital axial stiffness and muscular hypertonus. In one patient the phenotype evolved into an axial/proximal skeletal myopathy without distal involvement or cardiomyopathy, whereas the other patient exhibited predominantly stiffness and respiratory involvement. We review and compare all patients described in the literature who possess a variant predicted to alter the p.Glu500 residue in the ß-cardiac myosin head domain, and we provide in-silico analyses of potential effects on polypeptide function. CONCLUSION: The data presented here expand the phenotypic spectrum of mutations in the MYH7 gene and have implications for future diagnostics and therapeutic approaches.

Adverse events associated with deep brain stimulation in patients with childhood-onset dystonia.

BACKGROUND: Data on pediatric DBS is still limited because of small numbers in single center series and lack of systematic multi-center trials. OBJECTIVES: We evaluate short- and long-term adverse events (AEs) of patients undergoing deep brain stimulation (DBS) during childhood and adolescence. METHODS: Data collected by the German registry on pediatric DBS (GEPESTIM) were analyzed according to reversible and irreversible AEs and time of occurrence with relation to DBS-surgery: Intraoperative, perioperative (<4 weeks), postoperative (4 weeks < 6 months) and long term AEs (>6 months). RESULTS: 72 patients with childhood-onset dystonia from 10 DBS-centers, who received 173 DBS electrodes and 141 implantable pulse generators (IPG), were included in the registry. Mean time of postoperative follow-up was 4.6 ±â€¯4 years. In total, 184 AEs were documented in 53 patients (73.6%). 52 DBS-related AEs in 26 patients (36.1%) required 45 subsequent surgical interventions 4.7 ±â€¯4.1 years (range 3 months-15 years) after initial implantation. The total risk of an AE requiring surgical intervention was 7.9% per electrode-year. Hardware-related AEs were the most common reason for surgery. There was a tendency of a higher rate of AEs in patients aged 7-9 years beyond 6 months after implantation. DISCUSSION: The intraoperative risk of AEs in pediatric patients with dystonia undergoing DBS is very low, whereas the rate of postoperative hardware-related AEs is a prominent feature with a higher occurrence compared to adults, especially on long-term follow-up. CONCLUSION: Factors leading to such AEs must be identified and patient management has to be focused on risk minimization strategies in order to improve DBS therapy and maximize outcome in pediatric patients.

Pompe disease in Austria: clinical, genetic and epidemiological aspects.

In this study, we performed a survey of infantile and late-onset Pompe disease (IOPD and LOPD) in Austria. Paediatric and neuromuscular centres were contacted to provide a set of anonymized clinical and genetic data of patients with IOPD and LOPD. The number of patients receiving enzyme replacement therapy (ERT) was obtained from the pharmaceutical company providing alglucosidase alfa. We found 25 patients in 24 families, 4 IOPD and 21 LOPD with a resulting prevalence of 1:350,914. The most frequent clinical manifestation in LOPD was a lower limb-girdle phenotype combined with axial weakness. Three patients were clinically pauci- or asymptomatic and were diagnosed because of persistent hyperCKemia. Diagnostic delay in LOPD was 7.4 ± 9.7 years. The most common mutation was c.-32-13T > G. All IOPD and 17 symptomatic LOPD patients are receiving ERT. Standardized follow-up was only available in six LOPD patients for the 6-min walk test (6minWT) and in ten for the forced vital capacity (FVC). Mean FVC did not decline (before ERT; 63.6 ± 39.7%; last evaluation during ERT: 61.9 ± 26.9%; P = 0.5) while there was a trend to decline in the mean distance covered by the 6minWT (before ERT: 373.5 ± 117.9 m; last evaluation during ERT: 308.5 ± 120.8 m; P = 0.077). The study shows a lower prevalence of Pompe disease in Austria than in other European countries and corroborates a limb-girdle phenotype with axial weakness as the most common clinical presentation, although asymptomatic hyperCKemia may be the first indication of LOPD.

Tumor-induced hypophosphatemic rickets in an adolescent boy--clinical presentation, diagnosis, and histological findings in growth plate and muscle tissue.

CONTEXT: The mechanism behind disabling muscle weakness in tumor-induced hypophosphatemic rickets is obscure. Histological investigation of growth plate tissue of patients with tumor-induced osteomalacia has so far not been reported. PATIENT: A mesenchymal tumor was detected in the left distal fibula by (68)Ga-DOTATOC in a 17-yr-old boy with adolescent onset of severe hypophosphatemic rickets. Disabling muscle weakness improved within days after surgery, and normal mobility was restored within months. METHODS AND RESULTS: The resected tissue included part of the growth plate allowing immunohistochemical investigation. Positive staining of FGF23 was found in the tumor cells and in hypertrophic chondrocytes, osteoblasts, and osteoclasts of the adjacent growth plate. This distribution matched that found in growth plate tissue of a healthy control. We found positive staining for the somatostatin receptor not only in the tumor but also within the growth plate and adjacent bony tissue in the patient and the healthy control. Muscle tissue provided evidence for a partial defect in respiratory chain complexes I-IV. Biochemical markers were nearly or completely restored to normal 12 months after surgery. CONCLUSIONS: Hypertrophic growth plate chondrocytes are a target or source of FGF23 in tumor-induced osteomalacia. Low serum phosphate, FGF23, or other factors produced by the tumor may interfere with mitochondrial function.

Isolated cytochrome c oxidase deficiency as a cause of MELAS.

BACKGROUND: MELAS (mitochondrial myopathy, encephalopathy, lactic acidosis and stroke-like episodes) is one of the more common mitochondrial encephalomyopathies. About 80% of MELAS cases are caused by transition 3243A-->G in the mitochondrial tRNA(Leu(UUR)) gene (MT-TL1). Other mutations in MT-TL1, other mitochondrial tRNA genes and mitochondrial-encoded subunits of respiratory complex I account for the remainder of cases. OBJECTIVE: To characterise the molecular basis of a MELAS case without a mutation in any recognised MELAS target gene. RESULTS AND METHODS: Deletion of a single nucleotide (7630delT) within MT-CO2, the gene of subunit II of cytochrome c oxidase (COX), was identified by mitochondrial DNA (mtDNA) sequencing. The deletion-induced frameshift results in a stop codon close to the 5' end of the reading frame. The lack of subunit II (COII) precludes the assembly of COX and leads to the degradation of unassembled subunits, even those not directly affected by the mutation. Despite mitochondrial proliferation and transcriptional upregulation of nuclear and mtDNA-encoded COX genes (including MT-CO2), a severe COX deficiency was found with all investigations of the muscle biopsy (histochemistry, biochemistry, immunoblotting). CONCLUSIONS: The 7630delT mutation in MT-CO2 leads to a lack of COII with subsequent misassembly and degradation of respiratory complex IV despite transcriptional upregulation of its subunits. The causal association of the resulting isolated COX deficiency with MELAS is at odds with current concepts of the biochemical deficits underlying this common mitochondrial disease, and indicates that the genetic and pathobiochemical heterogeneity of MELAS is greater than previously appreciated.

[Psychosocial adjustment, relationship and self-concept in siblings of children with idiopathic epilepsy syndromes]. / Geschwister epilepsiekranker Kinder: Welche Auswirkungen haben idiopathische Epilepsien im Kindesalter auf die psychosoziale Anpassung, die Geschwisterbeziehung und das Selbstkonzept der Geschwister?

BACKGROUND: Psychosocial adjustment, relationship and self-concept in siblings of children with idiopathic epilepsy was compared with healthy controls. PATIENTS: 173 persons--68 siblings, 62 mothers and 43 fathers--from the study group (children with idiopathic epilepsy) and matched controls were investigated. METHODS: Child Behaviour Checklist (CBCL), Self-Description-Questionnaire I and II (SDQ) and Sibling Relationship Questionnaire (SRQ) were used. RESULTS: There were more somatic complaints of the siblings reported by the mothers of the study group. They also noted more nurturance of the sibling than mothers of healthy children did. The data of the fathers showed more dominance of the sibling. Siblings of children with epilepsy showed more prosocial action towards their classmates. In families with a new diagnosed epilepsy the fathers noticed more problems in school und somatic complaints of the siblings. The number of seizures, which were seen by the sibling, not the absolute number of seizures, had an influence on the behavior of the siblings; these siblings had more social problems than siblings, who had never seen a seizure. CONCLUSIONS: We suggest a close cooperation with the families and constant inclusion in the treatment as claimed by recent systemic family medicine. Resource-orientated and salutogenetic aspects should be given a greater focus in modern work with families and especially siblings.

[Family dynamics and chronic illness: children with diabetes in the context of their families]. / Familiendynamik bei chronischer Krankheit: Das diabeteskranke Kind im Kontext Familie.

The present study is based on the assumption of an interaction between family functioning and chronic illness. Using a systemic approach, the intra-familial situation of families with a diabetes-affected child is examined. 44 families were evaluated using a family diagnostic instrument ("Familienbögen") and compared with 31 control families with a healthy child. Furthermore, the study looked at the influence of the level of family functioning on glycemic control, as measured by HbA1c values, and vice versa. Families with a child affected by diabetes showed significantly more dysfunctional domains and higher discrepancies of the ratings in the family diagnostic instrument (p < 0.05). Unexpectedly, no significant interaction between family functioning and glycemic control was found. Poor glycemic control therefore did not have any negative effects on the family dynamics, in fact, the opposite was often the case. Also, the relationship between siblings was judged more positively when one of the siblings was chronically ill (p < 0.05). The results show that despite the fact that diabetes in children may lead to an increase in impairment of intra-familial dynamics, it may, at the same time, offer opportunities for an improvement of family relationships. However, if physiological parameters deteriorate in the child (poor glycemic control), family problems seem to become less important. Success in the treatment of diabetes patients should therefore not only be measured by the quality of glycemic control, but also by considering psychological factors and aspects of family dynamics.

[Hyperekplexia -- a treatable neuropediatric disease]. / Hyperekplexie -- eine behandelbare neuropädiatrische Erkrankung.

Hyperekplexia (OMIM 138491) is primarily an autosomal dominant disease characterized by exaggerated startle reflex and neonatal hypertonia. If untreated it can be associated with sudden infant death from apnea or aspiration pneumonia and serious injuries. Different mutations of the alpha1-subunit of inhbitory glyzine receptor (GLRA1) could be found. Clonazepame, a gammaaminobutyric acid (GABA) receptor agonist is the therapy of choice. An early diagnose will lead to appropriate treatment and genetic counseling.

Recruitment of bone-marrow-derived cells by skeletal and cardiac muscle in adult dystrophic mdx mice.

It is commonly accepted, that regenerative capacity of striated muscle is confined to skeletal muscle by activation of satellite cells that normally reside quiescent between the plasmalemma and the basement membrane of muscle fibers. Muscular dystrophies are characterized by repetitive cycles of de- and regeneration of skeletal muscle fibers and by the frequent involvement of the cardiac muscle. Since during the longstanding course of muscular dystrophies there is a permanent demand of myogenic progenitors we hypothesized that this may necessitate a recruitment of additional myogenic precursors from an undifferentiated, permanently renewed cell pool, such as bone marrow (BM) cells. To this end normal and dystrophic (mdx) female mice received bone marrow transplantation (BMT) from normal congenic male donor mice. After 70 days, histological sections of skeletal and cardiac muscle from BMT mice were probed for the donor-derived Y chromosomes. In normal BMT recipients, no Y chromosome-containing myonuclei were detected, either in skeletal or in cardiac muscle. However, in all samples from dystrophic mdx skeletal muscles Y chromosome-specific signals were detected within muscle fiber nuclei, which additionally were found to express the myoregulatory proteins myogenin and myf-5. Moreover, in the hearts of BMT-mdx mice single cardiomyocytes with donor derived nuclei were identified, indicating, that even cardiac muscle cells are able to regenerate by recruitment of circulating BM-derived progenitors. Our findings suggest that further characterization and identification of the BM cells capable of undergoing myogenic differentiation may have an outstanding impact on therapeutic strategies for diseases of skeletal and cardiac muscle.

Kinking and stenosis of the carotid artery associated with homolateral ischaemic brain infarction in a patient treated with cyclosporin A.

UNLABELLED: We present a 3-year-old patient with stenotic kinking of the left internal carotid artery (ICA) who developed an ischaemic infarction of the left brain hemisphere followed by severe neurological sequelae after a prolonged generalized seizure. At time of the seizure the boy was in biological remission of a nephrotic syndrome and received prednisolone and cyclosporin A (CsA) treatment. The haemodynamic consequences of inborn kinking of the ICA is discussed controversely in the literature. The presented case shows that stenotic kinking of the ICA may significantly impair the blood flow towards the homolateral hemisphere and therefore may result in an ischaemic infarction. The influence of CsA on seizure activity is discussed. CONCLUSION: This case provides clinical and radiological evidence supporting an association between stenotic kinking of the carotid artery and homolateral hemispheric brain infarction.

Auditory evoked potentials in young patients with Down syndrome. Event-related potentials (P3) and histaminergic system.

Subjects with Down syndrome exhibit various types of cognitive impairment. Besides abnormalities in a number of neurotransmitter systems (e.g. cholinergic), histaminergic deficits have recently been identified. Brainstem auditory evoked potentials (BAEPs) and auditory event-related potentials (ERPs), were recorded from 10 children (aged 11-20 years) with Down syndrome and from 10 age- and sex-matched healthy control subjects. In Down subjects, BAEPs revealed shortened latencies for peaks III and V with shortened interpeak latencies I-III and I-V. ERPs showed a delay of components N1, P2, N2 and P3. In addition, subjects with Down syndrome failed to show P3 amplitude reduction during repeated stimulation. To evaluate the cognitive effects of histaminergic dysfunction, ERPs were recorded from 12 healthy adults (aged 20-28 years) before and after antihistaminergic intervention (pheniramine) compared to placebo. Whereas components N1, P2, N2 remained unchanged after H1-receptor antagonism, P3 latency increased and P3 amplitude showed no habituation in response to repeated stimulation. The results suggest that the characteristic neurofunctional abnormalities present in children with Down syndrome must be the consequence of a combination of structural and neurochemical aberrations. The second finding was that antihistaminergic treatment affects information processing tested by ERPs similar to that seen with anticholinergic treatment.

Brainstem auditory evoked potentials and visually evoked potentials in young patients with IDDM.

OBJECTIVE: To investigate whether young IDDM patients develop central nervous dysfunction and to establish a possible relationship with various disease parameters. RESEARCH DESIGN AND METHODS: Thirty-two patients, aged 13.5 +/- 2 years, with disease duration of 6 +/- 2.6 years and age of onset of 7.7 +/- 3.2 years (group 1), and 21 patients with short-term disease, age 9.7 +/- 3.5 years, duration of disease < 2 years and age of onset of 9.4 +/- 3.3 years (group 2) were compared with age- and sex-matched control subjects. Exclusion criteria were clinical signs of neuropathy, retinopathy, nephropathy, or hearing impairment. Neurophysiological studies included auditory and visually evoked potentials (EPs). RESULTS: Patients in group 1 revealed increased P100 latencies of visually EPs (103.4 +/- 4.5 vs. 96.8 +/- 3.7 ms) and interpeak latencies I-V of auditory EPs (4.16 +/- 0.10 vs. 3.99 +/- 0.09 ms) and had abnormal latencies (values outside 2.5 SD) in 37%. However, short-term patients (group 2) had results within normal limits compared with control subjects. In group 1, longer disease duration and younger age at onset correlated with an increase of P100 latency (P < 0.001) and IPL I-V (P < 0.001). Patients with a history of severe hypoglycemic episodes had increased latencies compared with patients without hypoglycemia (P < 0.05). Furthermore, metabolic control during the last 2 years was related to P100 latencies (P < 0.05). CONCLUSIONS: EPs noninvasively detect subclinical central nervous system involvement in children and adolescents with IDDM. Most important risk factors are duration of disease and frequency of severe hypoglycemia.

[Function and structure of families with chronically ill children]. / Funktion und Struktur von Familien mit chronisch kranken Kindern.

In modern medicine especially the sick child often points out the limits of the psychosocial potentialities. This project investigates the function, structure, coping mechanisms, power and weakness of families with chronically ill children. We investigated 28 children from the nephrological ward and 55 patients from the cardiological department and also their families with the FAM III and compared the obtained T-scores with the results of the control-group (76 families, t-test, analysis of variance). Families with patients after renal transplantation (NTX) pointed out significant worse T-scores than the group with patients on CAPD or with preterminal renal insufficiency and CG (p < 0.05). Within the cardiological groups the differences were not statistically significant, on the other hand the group with patients before heart-operation and the group with patients after palliative heart-operation had better T-scores than the CT (p < 0.05). These results demonstrate that families with children suffering from a chronic renal or heart disease mobilize substantial resources to cope with these problems. By contrast the results of the families with patients after NTX or successful heart surgery are significant worse than the control-group and the other investigated patients groups. Our results come to the conclusion that especially after successful NTX or heart-surgery a psychosocial care of these families is necessary.

Prognosis of childhood epilepsy in newly referred patients.

The aim of this study was to investigate the prognosis of childhood epilepsy and to analyze prognostic factors in addition to remission rate in a follow-up of newly referred patients. Two hundred eighty-one patients were followed for a mean period of 5.3 years. Overall, 253 patients (90%) achieved 1-year remission. The beginning of a 1-year seizure-free period was achieved in 77.9% by 1 year, in 84% by 2 years and in 88.6% by 3 years after onset of treatment. Early onset of seizures, symptomatic etiology, and neurologic handicap predicted a worse prognosis. In 44 of 253 children with complete suppression of seizures for 1 year, relapses occurred within the follow-up period. In one child with a relapse, remission could not be achieved in the 2nd year thereafter. In conclusion, our study shows a good prognosis for most children with epilepsy, especially in patients with idiopathic epilepsy and late onset of seizures and without neurologic dysfunction. Moreover, our data strongly suggest that the long-term pattern of seizure control is largely established during the first 2 years of treatment.

Hematologic manifestations and impaired liver synthetic function during valproate monotherapy.

In a prospective study 50 children with new onset epilepsy were investigated. Routine screening for complete blood count, serum protein, albumin, gamma-glutamyltransferase (gamma-GT), aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase, and coagulation studies before, 3, 6 and 9 weeks after commencement of antiepileptic therapy with valproate were carried out. Serum B12 and folate levels were also determined in 29 patients. The aim of the study was to evaluate the effect of VPA on these laboratory findings. We found a significant reduction of red blood count and platelet count, whereas MCV showed a significant upward trend. Vitamin B12 levels were elevated after starting VPA therapy. We found no elevations of liver enzymes, but a significant transient reduction of ALT after 3 and 6 weeks and significantly reduced serum protein and albumin after 3, 6 and 9 weeks. Coagulation studies revealed a significant downward trend in serum fibrinogen and upward trend in thrombin time. The other parameters showed no significant changes after onset of VPA treatment. We think that reduced red blood cell and platelet counts, and elevated MCV indicate a direct toxic effect on a hematopoietic precursor or stem cell in patients treated with VPA. Furthermore, reduced protein, albumin and fibrinogen indicate an impaired liver synthetic function in asymptomatic children treated with VPA monotherapy.