Prevalence of the 35delG mutation in the GJB2 gene in two samples of non-syndromic deaf subjects from Chile

Hearing loss is the most common inherited sensorial deficiency in humans; about 1 in 1000 children suffer from severe or profound hearing loss at birth. Mutations in the GJB2 gene are the most common cause of prelingual, non-syndromic autosomal recessive deafness in many populations; the c.35delG mutation is the most common in Caucasian populations. The frequency of the c.35delG mutation was estimated in two samples of deaf patients from Santiago, Chile. Unrelated non-syndromic sensorioneural deaf patients were examined: Group 1 consisted of 47 unrelated individuals with neurosensory deafness referred to the Chilean Cochlear Implant Program; Group 2 included 66 school children with prelingual deafness attending special education institutions for deaf people. Individuals with profound to moderate isolated neurosensory hearing loss with unknown etiology were included. The presence of the c.35delG mutation was evaluated by the allele-specific polymerase chain reaction method (PCR), and in some cases it was confirmed by direct DNA sequencing of the coding region of the GJB2 gene. Deaf relatives were present in 20.3% of the cases. We found 19.5% (22/113) patients with the c.35delG mutation, 6 of them homozygous; these rates are similar to frequencies found in other Latin American countries.

Causas de sorderas profundas en niños chilenos asistentes a escuelas especiales para sordos / Causes of severe deafness in Chilean children enrolled in special schools for the deaf

La relación entre la audición y el desarrollo del lenguaje ha sido ampliamente demostrada, se aprende a hablar imitando los sonidos oídos y dándole la interpretación que oralmente los padres enseñan. Por ello, todos los países se están esforzando por realizar un tamizado universal en neonatos. El Estado de Chile, en un primer esfuerzo por detectar tempranamente las sorderas, está aplicando un tamizado auditivo a neonatos de alto riesgo. No hay en Chile estudio sobre las causas de sorderas, por lo cual se decidió investigar sobre esta materia en un grupo de niños sordos que estudia en alguna de las 4 escuelas especiales de Santiago. Conociendo las causas de sorderas congénitas y las de instalación en la infancia temprana, posibilita su prevención en el control del embarazo y de niño sano. Objetivo: Establecer las causas de sorderas profundas, según los conocimientos de sus padres o tutor legal y ficha escolar, en niños y jóvenes estudiantes de escuelas especiales para sordos. Material y método: En este estudio observacional, el universo fueron todos los niños que asisten a 4 escuelas especiales para sordos en Santiago. La muestra estuvo constituida por 315 casos que representan al 92 por ciento del universo. Se revisaron las fichas escolares de estos niños y la información se contrastó y completó con una entrevista a los padres o tutores. Conclusiones: El 63 por ciento de los niños presentaba sordera congénita, entre ellos el 9 por ciento fue por infección materna. Del total de la población, el 41.5 por ciento presentó sordera congénita de causa desconocida; el 13 por ciento fue adquirida por meningitis y en el 5.8 por ciento de los casos por prematurez.

The relationship between hearing and language development has been widely demonstrated, as children learn to speak by imitating sounds and interpreting them as they are orally taught by their parents. Because of this, countries are trying to put more emphasis on universal screening of newborns. In Chile, the first efforts of early detection of deafness have been in screening high risk newborns. En Chile there are no studies on the causes of deafness, and for this reason the present study seeks to investigate this issue in a group of Deaf children in special schools in Santiago. Understanding the causes of congenital and early childhood deafness allows for better prevention during pregnancy and early childhood. Objective: Establish the causes of severe deafness, according to the knowledge of parents or legal guardians and school records, in young students in special schools for the Deaf. Materials and Methods: In this observational study, the universe consisted of all children that attend 4 special schools for the Deaf in Santiago. The sample consisted of 315 cases, which represent 92 percent of the universe. School records were examined and information was contrasted and completed with and interview with parents or guardians. Conclusions: 63 percent of children suffered from congenital deafness, 9 percent of those due to infection during pregnancy. In 41.5 percent of all cases the cause of deafness was unknown. 13 percent was due to meningitis, and 5.8 percent was due to prematurity.

Medición de presión pulmonar en hiperplasia adenoamigdalina / Pulmonary pressure measurement in adenotonsillar hyperplasia

Se realiza un estudio de medición de presión pulmonar en un grupo de 24 niños con hiperplasia adenoamigalina severa que presentan crisis de apnea obstructiva durante el sueño y se compara con un grupo de 10 niños sanos. Las edades de los niños fluctuan entre los 2 y 8 años. A todos se les efectuó un electrocardiograma (ECG) y un ecocardiograma Doppler (ECO-D) midiendo la presión media pulmonar (PMP), presión sistólica (PS) y la presión diastólica (PD). En todos los niños las mediciones de presión pulmonar y el ECG, estuvieron dentro de rangos normales no demostrando hipertensión pulmonar (HTP)

Técnica osteoplástica del seno frontal / Osteoplastic technic of the frontal senus

The authors present their experience in osteoplastic surgery wihout obliteration in frontal sinusitis (Macbeth type). They analyze 21 patients; 13 males and 8 female. Twelve patient had a piomucocele or mucocele and 9 had acute complicated sinusitis. The long term results showed minor cosmetic deformities in 2 cases and in other two pacients the disease recurred, one of then underwent a second surgery

Hipoacusia sensorioneural plana / Plane sensoneural hypoacusia

The authors intend to diagnose and make a prognosis in 97 patients surffering from sensoryneural hearing loss with a flat audiometric pattern. Combining this hearing loss with the hearing of the contralateral ear, seven different groups are abtained. The clinical records are searched for blood sedimentation rate, serologic tests for syphilis, eight nerve examination, ear X rays and when possible, fluctuations of hearing. When a vestibular lesion was found, this was mostly in the eat suffering from flat hearing loss. In most cases the hearing loss is either stable or gets worse. The most frequent diagnosis was endolinphatic hidrops