RESUMO
Objective To analyze the clinical and imaging characteristics of congenital sensorineural hearing loss (CSNHL)children combined with white matter (WM)lesions in order to provide evidence for clinical practice. Methods With referral to the Department of Pediatrics,Peking University First Hospital from November 201 1 to De-cember 201 5,documents of 78 patients of CSNHL combined with WMlesions were collected and analyzed for the clini-cal and imaging characteristics.Results Bilateral severe -profound hearing loss existed in all 78 cases,48.1 %(25 /52 cases)of the patients exhibited gross motor development delay,98.1 %(51 /52 cases)of them had normal cognition development.One hundred percent (61 /61 cases)of patients had abnormal language development.Infection occurring during pregnancy existed in 21 .2%(1 1 /52 cases)of the patients,the premature and smaller for the gestational age in-fants accounted for 28.9% (1 5 /52 cases).The bilateral multiple WMlesions from the brain MRI were in dot to flake sizes with sharp boundary,the intensity of T1 -weighted imaging decreased,T2 -weighted imaging and fluid attenuated inversion recovery increased.Eighty -two point one percent (64 /78 cases)of the patients were found to have the periventricular and subcortical WM involvement.The most frequently affected periventricular region was the posterior horn (91 .9%,68 /74 cases),followed by the anterior horn and temporal horn,and the least with the body involvement. The former three had a combined lesion tendency (55.4% -68.9%).There was an extensive involvement in the sub-cortical WMof parietal,frontal,temporal and occipital lobes respectively(73.5% -88.2%).Subcortical WM involve-ment of multiple lobes was common (accounted for 67.6% -77.9%).The enlargement of bilateral ventricles existed in 37.2%(29 /78 cases)of the patients and cystic changes in the subcortical WM of anterior temporal lobe could be found in 9.0% (7 /78 cases)patients.Calcification in 2 CT cases was reported.Corpus callosum and basal ganglia of all cases were normal.For cases with MRI scans more than once,WMlesions of 96.0%(24 /25 cases)patients became silent or self -restored.Conclusions The clinical presentations of CSNHL combined with WM lesions are mild,not paralleled with their multiple foci.It is considered as demyelination or a delay of myelination.Due to its benign course, it is probably not the contraindication for the cochlear implantation.
RESUMO
If not detected and treated early, congenital sensorineural hearing loss generates impairment in linguistic, intellectual and social development of individuals. Most congenital hearing deficits are genetic. The most common causes are mutations in GJB2 and GJB6 genes, both located on chromosome 13, encoding junction proteins that allow the transduction of sound in the inner ear. Objetive: To evaluate the presence of mutations in GJB2 and GJB6 genes in a population of children diagnosed with deafness in Complejo Hospitalario Sótero del Río since implementation of the universal newborn hearing screening program. Patients and Methods: 8 patients with congenital nonsyndromic sensorineural deafness were evaluated. Genomic DNA was extracted from oral mucosa swabs. PCR was performed to identify the 35 del G mutation in GJB2, followed by sequencing of this gene, and PCR for 2 GJB6 deletions. Results: Two patients were heterozygous for 35 del G mutation in GJB2, being their other alleles normal. Another 2 patients were heterozygous for V27I polymorphism, one of them also accompanied by p.A148A (c.444C > A) variant. A patient was found with a previously undescribed mutation (c.4360 C>T) in GJB2's intron 1, being the second allele normal. No mutations were identified in GJB6. Conclusions: In this population of children, mutations in the GJB2 gene were an identifiable cause of congenital sensorineural.
La hipoacusia neurosensorial congénita es una patología frecuente que si no es detectada y tratada oportunamente genera alteraciones en el desarrollo del niño. Desde el año 2005 se lleva a cabo en el Complejo Hospitalario Dr. Sótero del Río un programa de screening auditivo universal para la detección precoz de esta patología. La mayor parte de los déficits auditivos congénitos son genéticos. La etiología más común son las mutaciones en los genes GJB2 y GJB6, que codifican para proteínas "gap junction" que permiten la traducción del sonido en el oído interno. Objetivo: Evaluar la presencia de mutaciones de los genes GJB2 y GJB6 en una población de niños diagnosticados con hipoacusia congénita en el Complejo Hospitalario Dr. Sótero del Río a través del programa de screening auditivo universal. Pacientes y Método: Se evaluaron 8 pacientes con hipoacusia congénita neurosensorial no sindrómica. Se extrajo ADN genómico de hisopado de mucosa bucal y se realizó PCR para identificar la mutación 35 del G en GJB2, seguida de secuenciación de este gen, y PCR para 2 deleciones del gen GJB6. Resultados: Dos pacientes fueron heterocigotos para la mutación 35 del G en GJB2, siendo sus otros alelos normales. Dos fueron heterocigotos para el polimorfismo V27I; uno acompañado por la variante p.A148A (c.444 C > A). Se encontró además un paciente con una mutación no descrita anteriormente (c.4360 C>T) en el intrón 1 de GJB2, siendo su segundo alelo normal. No se identificaron mutaciones en GJB6. Conclusiones: En este grupo de niños estudiados se encontró mutaciones en el gen GJB2, causantes de sordera neurosensorial congénita.