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15 recordsLinked to original sources

PubMed2026

Congenital core myopathy linked to SOX5: Expanding the phenotypical spectrum of Lamb-Shaffer syndrome.

Haploinsufficiency of SOX5 causes Lamb-Shaffer syndrome, a rare condition with developmental delay, impaired language and intellectual disability and optic nerve abnormalities. Muscle involvement is poorly characterized. We report a 20-year-old woman with neonatal hypotonia, delayed motor milestones, proximal weakness and learning difficulties. Serum creatine kinase was normal. Electroneuromyography revealed a mild myogenic pattern. Muscle biopsy revealed myopathic changes, with cores and protein aggregates. Whole genome sequencing disclosed a heterozygous pathogenic variant in the SOX5 gene. This case expands the phenotypic spectrum of Lamb-Shaffer syndrome, confirming primary muscle involvement with core myopathy.

Female↗

PubMed2026

Clinical Variability and Genotype-Driven Outcomes in CHRND-Related Congenital Myasthenic Syndrome.

BACKGROUND: Congenital myasthenic syndromes (CMS) caused by pathogenic variants in CHRND, encoding the δ-subunit of the nicotinic acetylcholine receptor (AChR), are rare, and data on genotype-phenotype correlations and long-term outcomes are limited. METHODS: We performed a retrospective, multicenter study of nine patients with genetically confirmed CHRND-related CMS from specialized neuromuscular centers. Clinical, electrophysiological, genetic, and therapeutic data were systematically collected. All diagnoses were established by exome sequencing during routine clinical work-up. RESULTS: Eight patients were compound heterozygous and one was homozygous for pathogenic CHRND variants, including nonsense, missense, splice-site variants, and one microdeletion. Disease onset ranged from the neonatal period (n = 7) to adolescence (n = 2). Three patients were followed longitudinally for 22-43 years. Ocular involvement, particularly ptosis and ophthalmoparesis, was present in all patients. Generalized fatigable weakness was common, whereas bulbar and respiratory involvement occurred in a subset and reflected overall disease severity. Genotypes including a null allele or a homozygous missense variant tended to be associated with more severe phenotypes, while compound heterozygous missense variants were linked to a broader and generally milder spectrum, sometimes limited to ocular symptoms. Long-term outcomes ranged from minimal symptoms under therapy to severe motor impairment with respiratory insufficiency, highlighting substantial interindividual variability. CONCLUSIONS: This study expands the phenotypic and genotypic spectrum of CHRND-related CMS and underscores the critical role of genotype in determining disease severity. Comprehensive genetic testing, longitudinal phenotyping, and genotype-informed management are essential for optimal diagnosis and care in this rare disorder.

Humans↗

PubMed1979

Neonatal respiratory insufficiency due to centronuclear myopathy.

Two neonates showing generalized hypotonia, weakness of limbs, trunk, and oral musculature died because of muscular respiratory distress. The diagnosis of centronuclear (or myotubular) myopathy was established by histological and histochemical techniques. The genetic situation and routine laboratory data including electromyography were compared with similar cases in the literature; findings were inconclusive with respect to this diagnosis. These results indicate the need for a muscle biopsy and the use of histochemical stainings and/or electronmicroscopical investigation for a proper diagnosis in hypotonic newborns under respiratory distress after exclusion of etiologies other than neuromuscular diseases. Still the diagnosis of centronuclear myopathy in a neonate does not allow a precise prognosis. Increased awareness of this disorder and adequate diagnostic workup is needed in order to extend our understanding and to clarify the prognosis.

Humans↗

PubMed1979

Low urinary estriol during pregnancy caused by isolated fetal ACTH-deficiency.

In a 34-year-old pregnant woman, serum HPL and urinary HCG were normal, but urinary estriol was repeatedly low. A normal boy was delivered after 38 week gestation. During the neonatal period, he had hypoglycemia, muscular hypotonia and transient hyperbilirubinemia. The ACTH-test was normal, but the THS-response to metyrapone was low. Serum ACTH did not respond to insulin and metyrapone. Growth hormone, TSH and gonadotropin responses to stimuli were normal. Treatment with hydrocortisone resulted in disappearance of the symptoms. It is concluded that fetal ACTH-deficiency is one of the specific endocrine causes of low maternal estriol.

Adrenocorticotropic Hormone↗

PubMed2026

A New Case of Lethal Congenital Contracture Syndrome Type 3 With Hyperinsulinism and Optic Atrophy.

Lethal congenital contracture syndrome 3 (LCCS3, MIM #611369) is a rare autosomal recessive neuromuscular disorder caused by biallelic loss-of-function (LOF) variants in PIP5K1C, reported in only two families to date. It typically presents with severe fetal akinesia, arthrogryposis multiplex congenita, and perinatal lethality due to respiratory insufficiency case. Herein, we report a new case with survival beyond birth. Prenatal findings included clubfeet with preserved amniotic fluid volume and fetal movements. The infant was delivered by cesarean section at 37 + 7 weeks following breech presentation and developed respiratory distress requiring 14 days of ventilatory support. Physical examination revealed bilateral talipes equinovarus, flexion contractures of the knees, restricted hip mobility, clenched hands with flexion contractures of the third and fourth fingers, and hyperextension of the second and fifth fingers. Neurologically, he had encephalopathy, profound hypotonia with a frog posture, and abnormal neonatal reflexes with a discontinuous background pattern on cerebral function monitoring. Additional observed features were bilateral optic atrophy and hyperinsulinemic hypoglycemia responsive to Diazoxide. Trio genome sequencing identified a homozygous pathogenic splice-site variant in PIP5K1C (c.1127+1G>A, NM_012398.3). The infant died at 6 months from multisystemic failure. Further studies are warranted to elucidate the pathomechanisms underlying the PIP5K1C defect and its phenotypic consequences.

LCCS3↗

PubMed1978

[The myocardiopathies of glycogenosis].

Thirty-three patients with glycogen abnormalities and myocardial disease were studied. 27 of them has type II glycogen disorders (Pompe's disease, with an intralysozymal deficit of acid maltase) and 6 with type III glycogen disorders Forbes disease, with a deficit in amylo-1-6-glucosidase). The picture of a type II abnormality in the infant is very standard: early onset, often neonatally; the association with asystole and muscular hypotonia and a characteristics clinical picture; invariable cardiomegaly and typical ECG findings (short PR interval, high voltage complexes). Death occurs before one year of age, treatment has limited effect, and attention is centred on the early discovery of heterozygotes and of diagnosis antenatally. The possibility of an obstructive type (4 out of 24) and a type with endocardial fibroelastosis (3 out of 24) must be emphasised. In the late onset myopathic form of type II disorder (3 cases), involvement of the myocardium is always found, but is of secondary importance in determining the clinical picture and natural history. The same can be said of type III disorders in which, despite the infrequency of asystole or significant cardiomegaly, a hypertrophic cardiomyopathy which may be obstructive can lead to sudden death in infancy (2 cases out of 6).

Angiocardiography↗

PubMed1977

Neonatal ophthalmoplegia with microfibers: a reversible myopathy?

An infant born with marked hypotonia showed prompt regression of skeletal muscle weakness, but by 7 weeks of age had total external ophthalmoplegia. Biopsy of the gluteus muscle at 14 days showed marked variation in fiber size with a large proportion of very small fibers (less than 3 mu). By 10 months of age, biopsy of the vastus was virtually normal. The inferior oblique muscle was replaced by fibrous tissue containing a few remaining degenerating fibers. The child was normal at 2 years of age except for mild facial weakness and ophthalmoplegia. This syndrome may be the result of a reversible intrauterine process.

Child, Preschool↗

PubMed1979

Neonatal hypothyroidism detected by the Northwest Regional Screening Program.

The Northwest Regional Screening Program to detect congenital hypothyroidism in infants born in Oregon, Montana, Alaska, and Idaho (combined birthrate of 69,000/ yr) was added to our ongoing screening program in 1975. The program utilizes dried blood filter paper specimens collected routinely in the first few days of life in all four states and again at about 6 weeks of age in Oregon only. The screening test consist of an initial thyroxine (T4) measurement; a thyroid-stimulating hormore (TSH) determination is performed on those specimens with T4 concentrations in the lowest 3% group. Serum samples obtained by venipuncture are requested for confirmation of the diagnosis. In the first two years of the program, 25 infants with primary hypothyroidism were detected amont 110,667 infants screened, a frequency of 1:4,430. Fourteen cases of thyroxine-binding globulin deficiency were also detected, a frequency of 1:7,900. Using the T4 followed by TSH testing approach, the frequency of request for repeat specimens was 0.4% in Oregon and 0.05% in the other states. The cost per specimen was $1.96. The majority of infants lacked clinical signs or symptoms of hypothyroidism; only one infant was clinically suspected of having hypothyroidism prior to detection. The most common neonatal symptoms were constipation, lethargy, and prolonged jaundice, while the most common physical signs were hypotonia, umbilical hernia, and large fontanels. Thyroid scans showed the most common etiology to be thyroid aplasia, followed by an ectopic gland, hypoplasia, and goiter. Serum T4 concentrations were lowest in those infants with aplasia, intermediate in infants with an ectopic gland or hypoplasia, and normal in the infant with the goiter. Neonatal hypothyroidism varies in degree and has several different causes; the capacity to secrete thyroid hormone, the duration before hypothyroidism becomes clinically manifest, and possibly the eventual prognosis for intellectual function depend on the nature of the underlying cause. While the mean age at treatment was 59 days, the goal of diagnosing congenital hypothyroidism and treating affected infants by 1 month of age seems realistic.

Congenital Hypothyroidism↗

PubMed2026

Brainstem Disconnection Syndrome in a Patient With Respiratory Failure and Failed Weaning From Oxygen: A Case Report.

BACKGROUND: Brainstem disconnection syndrome (BDS) is an exceedingly rare congenital malformation of the hindbrain characterized by disconnection of the brainstem, often presenting with severe neurological deficits and early neonatal mortality. Whereas previous cases have documented isolated neurological anomalies, this report delineates a distinctive presentation of BDS associated with a specific constellation of multisystem vascular and extracerebral skeletal malformations. CASE PRESENTATION: A 4-month-old female infant, born from a discordant twin pregnancy, exhibited persistent neonatal respiratory failure, failure to wean from oxygen therapy, global tonic-clonic seizures, and severe hypotonia. Magnetic resonance imaging (MRI) and magnetic resonance angiography (MRA) of the brain demonstrated a complete absence of the pons, a slender tissue cord connecting the midbrain and medulla oblongata, extensive cerebellar hypoplasia, and nonopacification or aplasia of the basilar and distal vertebral arteries. Whole exome sequencing did not reveal any standard inherited neurodevelopmental mutations; however, genomic analysis identified carrier status for a biologically plausible frameshift variant in TMEM67, a gene heavily implicated in ciliary hindbrain morphogenesis. The implementation of targeted supportive care allowed the patient to survive beyond the typical early neonatal period, with the patient remaining alive at a 12-month follow-up. CONCLUSION: This case broadens the known phenotypic and radiological range of BDS by reporting new multilevel skeletal and vascular co-occurring conditions. The notable phenotypic differences seen in this twin pregnancy support the theory of early embryonic vascular disruption. Additionally, the detection of the TMEM67 variant indicates that ciliary gene mutations could be important genetic factors or modifiers in BDS.

MRI neonate↗

PubMed1979

Neonatal signs as predictors of cerebral palsy.

Signs of neonatal neurologic dysfunction, recorded in approximately 40,000 infants, were evaluated prospectively for their ability to predict later motor handicap. Tenfold to 33-fold increases in risk of cerebral palsy (CP) were observed in surviving children with any one of the following characteristics: birth weight less than 2,000 gm, head circumference more than 3 SD above or below the mean, five minute Apgar score of 3 or less, diminished activity or diminished cry lasting for more than one day, thermal instability, need for gavage feeding, hypotonia or hypertonia, single or multiple apneic episodes, or hematocrit less than 40%. Of worse portent, with relative risks exceeding 50, were neonatal seizures or Apgar scores of 3 or less at ten minutes or later. These characteristics were also markers of considerable risk of early death. For 0.5% of surviving infants, an overall impression of abnormality of brain function during the nursery period was recorded by the attending physician; there was a 99-fold increase in CP among these children.

Apgar Score↗

PubMed1977

Carbamyl-phosphate-synthetase deficiency with neonatal onset of symptoms.

The clinical course and biochemical findings in a case of carbamyl-phosphate-synthetase deficiency are described. The patient, a boy, presented 48 h after birth with rapidly developing hypotonia and hypothermia. Pulmonary haemorrhage, melaena and haematemesis ensued and despite ventilatory assistance and peritoneal dialysis the patient died on the fifth day. A virtual absence of carbamyl phosphate synthetase I (N-acetylglutamate dependent) was proved by analysis of tissue samples removed post mortem. Other urea cycle enzymes were normal.

Amino Acids↗

PubMed2026

35 Individuals With HUWE1-Related Neurodevelopmental Disorder and Suggested Clinical Evaluations.

HUWE1 (HECT, UBA, and WWE Domain Containing E3 Ubiquitin Protein Ligase1, OMIM 300697), located at Xp11.22, encodes a ubiquitin ligase that is highly conserved across species. Genetic variants in HUWE1 described in multiple independent studies cause X-linked intellectual disability, including in the patients identified by Juberg, Marsidi, and Brooks. This report describes 35 additional cases of individuals with variants in HUWE1 and suggested guidelines for clinical management. Our study includes several female cases, which have not been widely reported previously. Our findings confirm earlier reported clinical features including developmental delay, autism, hypotonia, short stature, and dysmorphic facial features as well as additional multisystemic findings. Intrauterine growth restriction (IUGR) and feeding difficulties were common in the neonatal period. It is notable that nearly all females had de novo variants, and males had de novo or inherited variants from clinically unaffected carrier mothers. Three genetic hotspots were identified in evolutionarily conserved regions of HUWE1 that have clinical impact. This report provides additional characterization of the spectrum of HUWE1-related neurodevelopmental disorder (HNDD).

Humans↗

PubMed1978

Neonatal hyperammonaemia with complete absence of liver carbamyl phosphate synthetase activity.

Two newborn infants, male (A) and female (B), with lethal hyperammonaemia are described in the same family. In both, symptoms started on the second day of life. Lethargy and hypotonia were the most prominent initial findings and were followed by convulsions and coma. In both, blood ammonia levels rose to 570 mumol/u (795 microgram/100 ml) a few hours before death, which occurred on the third and fourth day of life respectively. Assay of liver urea cycle enzymes in baby B showed a complete absence of mitochondrial carbamyl phosphate synthetase activity.

Amino Acid Metabolism, Inborn Errors↗

PubMedDate not supplied

Differential diagnosis of infant botulism.

Clinical investigations of infants hospitalized with botulism demonstrate a remarkable uniformity of complaints and physical findings. Constipation precedes a course of progressive weakness and cranial nerve dysfunction. Examination reveals hypotonia, hyporeflexia, and a variable pattern of involvement of the motor cranial nerves. Initial laboratory investigations should include electrodiagnostic tests, because findings of an incremental response to rapid, repetitive nerve stimulation and of brief, small-amplitude motor units on electromyography are virtually pathognomonic of botulism in the infant. Differential diagnosis includes disorders that may produce generalized depression of the central nervous system, such as septicemia, meningitis, metabolic disturbances, and intoxications. Specific involvement of the neuromuscular system includes acute polyneuropathies, diseases of the anterior horn cell, congenital myopathies or muscular dystrophy, and neonatal myasthenia gravis. Recent studies have expanded the clinical spectrum of infant botulism to include some cases of sudden infant death syndrome and otherwise nonspecific constipation.

Action Potentials↗

PubMed1979

[A practicable method of polygraphic investigations in preterm and fullterm neonates (author's transl)].

Polygraphic recording techniques (simultaneous recording of several physiological variables) have been used earlier in investigations of normal newborn and preterm infants. The clinical value of prolonged polygraphic recordings in highrisk neonates is well-known. The main-purpose of this paper is to demonstrate a clinically practicable method of polygraphic recording technique, needing no more than two hours recording-time and its interpretation by means of visual analysis.

Brain Damage, Chronic↗