Enfoque clínico del recién nacido y lactante hipotónico / Neonatal hypotonia

El síndrome del niño hipotónico es una entidad bien reconocida por pediatras y neonatólogos. Se refiere a un niño con hipotonía generalizada presente desde el nacimiento o infancia precoz. Es el signo de disfunción neurológica más frecuente en el recién nacido y lactante, resultado de injurias agudas o crónicas a cualquier nivel del sistema nervioso, desde la corteza cerebral al músculo. Por la multiplicidad de causas y condiciones que subyacen a la hipotonía es imprescindible un enfoque ordenado y sistemático en la evaluación del niño hipotónico.

Floppy infant syndrome is a well recognized entity for pediatricians and neonatologists. It refers to a child with decreased muscle tone present at birth or in early infancy. It is the commonest sign of neurological dysfunction in newborns and infants, which can result from acute or chronic injuries at any level of the nervous system from cerebral cortex to muscle. Because of the multiple causes and conditions underlying hypotonia, asystematic assessment is essential in the approach to the floppy infant.

Congenital Myotonic Dystrophy with Asymptomatic Mother.

Myotonic dystrophy is an autosomal dominant neuromuscular disorder characterised by extreme pleiotropism and variability in disease expression. A congenital form is rare and is observed in infants born to symptomatic mothers with multisystem involvement. We report a case of a neonate with congenital myotonic dystrophy born to an asymptomatic mother.

Diagnostic Approach in Floppy Infants / 대한소아신경학회지

Floppy infant syndrome is a disease in which infants present with generalized hypotonia at birth or early infancy. There are many possible etiologies, which make a specific diagnosis difficult. The expanding knowledge of genetic disorders has made noninvasive genetic testing available for specific diagnoses. Therefore, it is very important for clinicians to use a systematic approach for the investigation of such children. In this chapter, I review the many possible etiologies of the floppy infant syndrome, and a systematic approach for the evaluation of this disorder will be proposed.

Diagnostic classification and clinical aspects of floppy infants in the neonatal and pediatric intensive care units / 소아과

PURPOSE: The purpose of this study is to make a diagnostic classification and discuss a diagnostic strategy of floppy infants by investigating clinical, neurological, electrophysiological, and genetic analysis of infants admitted to intensive care units with the complaint of hypotonia. METHODS: A retrospective study was performed from Jan. 1993 to Dec. 2005 in neonatal and pediatric intensive care units of Seoul National University Children's Hospital. Clinical features and all tests related to hypotonia were investigated. RESULTS: There were 21 cases of floppy infants admitted to intensive care units. Final diagnosis was classified as centra (7 cases[33.3 percent]), peripheral (11 cases [52.4 percent]), and unspecified (3 cases [14.3 percent]). Among the central group, three patients were diagnosed as hypoxic ischemic encephalopathy, two patients as Prader-Willi syndrome, one patient as chromosomal disorder, and one patient as transient hypotonia. Among the peripheral group, four patients were diagnosed as myotubular myopathy, three patients as SMA type 1, two patients as congenital myotonic dystrophy, one patient as congenital muscular dystrophy, and one as unspecified motor-neuron disease. Motor power was above grade 3 on average, and deep tendon reflex was brisk in the central group. Among investigations, electromyography showed 66 percent sensitivity in the peripheral group, and muscle biopsy was all diagnostic in the peripheral group. Brain image was diagnostic in the central group, and Prader-Willi FISH or karyotyping was helpful in diagnosis in central group. Morbidity and mortality was more severe in the peripheral group CONCLUSION: Classification of diagnosis by clinical characteristics in this study, and application of investigations step by step, may provide an effective diagnostic strategy.