Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0026827 (hypotonia)
 5,860 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Cephalic neural crest cells contribute to the formation of the external and middle ears, the supporting cells of the statoacoustic ganglion, other cranial nerve components, and the face. The anlage of otic sensory structures receive inductive stimuli from adjacent rhombencephalic tissue. The complex series of interactions that guide organogenesis of the outer, middle, and inner ear structures may explain why neurologic dysfunction is likely to be associated with malformations of the ear. We reviewed the records of 100 patients with complex ear anomalies with or without hearing loss. Mean age was 4.2 years (range 1 day-27 years). Malformations, either bilateral (70) or unilateral (30), involved the external ear (94), middle ear (16), and/or inner ear (12). Eighty-five patients had neurologic dysfunction. Cranial nerve dysfunction was found in 56 patients and involved nerves VIII (39 auditory and/or vestibular), VII (22), II (11), VI (8), V (4), III (3), X (3), XII (1), and IX (1). Sixty-four patients had evidence of central nervous system dysfunction such as mental deficiency/developmental delay (44), non-paretic gait disorders (17), hypotonia (16), microcephaly (13), seizures (8), motor deficits (8), autistic features (7), and radiographically confirmed intracranial abnormalities (5). Eleven of 19 children with hypoactive vestibules had delayed motor development or poor balance. Seventy-four patients had anomalies in other organ systems: 56 craniofacial, 28 osseous, 19 cardiac, 16 genito-urinary, 14 ocular, 11 gastrointestinal, and 7 cutaneous. Sixty-one patients had syndromic conditions, 32 of them branchial arch syndromes. The level of cognitive competence was not related to severity of craniofacial, ear, or cranial nerve abnormality. Children with ear malformations deserve neurologic and pediatric evaluations in addition to an otologic work-up.
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PMID:Neurologic findings in children with ear malformations. 362 8

Increased intracranial pressure and ventricular and subarachnoidal dilatation are common manifestations in achondroplasia. They rarely lead to major neurologic and/or psychomotor deficits and neurosurgical intervention is seldom needed. The present study was undertaken to detect signs of minor cerebral dysfunction and discuss possibilities of their prevention. Thirty children with achondroplasia were compared to 3 control groups: their next-born sibs, 30 children with other forms of dwarfism, and 30 children with normal height. Early development was assessed by means of questionnaires. Cognitive skills were evaluated with the German version of the Cognitive Abilities Test and the Lorge-Thorndike Intelligence Test. Personality data were tested using standardized neuroticism, extraversion, and anxiety scales. Children with achondroplasia had more frequent histories of delayed motor development, retarded speech development, and lower school grades in language-related specialties. Psychometric testing disclosed total and subtest scores in the population-based normal range. In comparison with their sibs and matched controls children with achondroplasia had significantly lower total scores mainly caused by low scores in the subtest "verbal comprehension." We conclude that verbal comprehension is significantly impaired in children with achondroplasia. This partial deficiency is probably related to frequent middle ear infections and resulting conductive hearing loss. Hypotonia with delayed oropharyngeal muscle coordination and parental response to an altered, more infantile instinctive releasing pattern may be contributing factors.
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PMID:Cognitive skills in achondroplasia. 826 16

We report on a boy with a maternal uniparental disomy for chromosome 14 (UPD(14)). At 7 years of age he was referred to us by the paediatrician because of symptoms of Prader-Willi syndrome (PWS). He showed short stature, obesity, mild developmental delay, cryptorchidism, and some mild dysmorphic features. The history further indicated intrauterine growth retardation at the end of the pregnancy. His mother was 44 years of age at the time of his birth. After birth he showed hypotonia with poor sucking, for which gavage feeding was needed. Motor development was delayed. After 1 year he became obese despite a normal appetite. Recurrent middle ear infections, a high pain threshold, and a great skill with jigsaw puzzles were reported. There were no behavioural problems or sleep disturbance. Chromosomal analysis was normal (46,XY). DNA analysis for Prader-Willi syndrome showed no abnormalities. Two years later he was re-examined because we thought his features fitted the PWS-like phenotype associated with maternal UPD(14). At that time precocious puberty was evident. DNA analysis showed maternal heterodisomy for chromosome 14. In all the previously described 11 cases with maternal UPD(14), a Robertsonian translocation involving chromosome 14 was detected cytogenetically before DNA analysis. This is the first report of diagnosis of maternal UPD(14) based on clinical features. This finding underlines the importance of DNA analysis for maternal UPD(14) in patients with a similar PWS-like phenotype even without previous identification of a Robertsonian translocation involving chromosome 14.
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PMID:Maternal uniparental disomy for chromosome 14 in a boy with a normal karyotype. 1052 60

The Smith-Magenis syndrome is a rare, complex multisystemic disorder featuring, mental retardation and multiple congenital anomalies caused by a heterozygous interstitial deletion of chromosome 17p11.2. The phenotype of Smith-Magenis syndrome is characterized by a distinct pattern of features including infantile hypotonia, generalized complacency and lethargy in infancy, minor skeletal (brachycephaly, brachydactyly) and craniofacial features, ocular abnormalities, middle ear and laryngeal abnormalities including hoarse voice, as well as marked early expressive speech and language delays, psychomotor and growth retardation, and a 24-hour sleep disturbance. A striking neurobehavioral pattern of stereotypies, hyperactivity, polyembolokoilamania, onychotillomania, maladaptive and self-injurious and aggressive behavior is observed with increasing age. The diagnosis of Smith-Magenis syndrome is based upon the clinical recognition of a constellation of physical, developmental, and behavioral features in combination with a sleep disorder characterized by inverted circadian rhythm of melatonin secretion. Many of the features of Smith-Magenis syndrome are subtle in infancy and early childhood, and become more recognizable with advancing age. Infants are described as looking "cherubic" with a Down syndrome-like appearance, whereas with age the facial appearance is that of relative prognathism. Early diagnosis requires awareness of the often subtle clinical and neurobehavioral phenotype of the infant period. Speech delay with or without hearing loss is common. Most children are diagnosed in mid-childhood when the features of the disorder are most recognizable and striking. While improvements in cytogenetic analysis help to bring cases to clinical recognition at an earlier age, this review seeks to increase clinical awareness about Smith-Magenis syndrome by presenting the salient features observed at different ages including descriptions of the neurologic and behavioral features. Detailed review of the circadian rhythm disturbance unique to Smith-Magenis syndrome is presented. Suggestions for management of the behavioral and sleep difficulties are discussed in the context of the authors' personal experience in the setting of an ongoing Smith-Magenis syndrome natural history study.
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PMID:Neurologic and developmental features of the Smith-Magenis syndrome (del 17p11.2). 1664 92

Systematic data regarding early neurodevelopmental functioning in Smith-Magenis syndrome are limited. Eleven children with Smith-Magenis syndrome less than 3 years of age (mean, 19 months; range, 5-34 months) received prospective multidisciplinary assessments using standardized measures. The total sample scored in the moderately to severely delayed range in cognitive functioning, expressive language, and motor skills and exhibited generalized hypotonia, oral-motor abnormalities, and middle ear dysfunction. Socialization skills were average, and significantly higher than daily living, communication, and motor abilities, which were below average. Mean behavior ratings were in the nonautistic range. According to exploratory analyses, the toddler subgroup scored significantly lower than the infant subgroup in cognition, expressive language, and adaptive behavior, suggesting that the toddlers were more delayed than the infants relative to their respective peers. Infants aged approximately 1 year or younger exhibited cognitive, language, and motor skills that ranged from average to delayed, but with age-appropriate social skills and minimal maladaptive behaviors. At ages 2 to 3 years, the toddlers consistently exhibited cognitive, expressive language, adaptive behavior, and motor delays and mildly to moderately autistic behaviors. Combining age groups in studies may mask developmental and behavioral differences. Increased knowledge of these early neurodevelopmental characteristics should facilitate diagnosis and appropriate intervention.
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PMID:Neurodevelopment of children under 3 years of age with Smith-Magenis syndrome. 1974 44