Objectives: Although hearing loss is a well-known symptom of mitochondria-related disorders, it is not clear how often it is a congenital and cochlear impairment. The Newborn Hearing Screening Program (NHSP) enables to distinguish congenital cochlear deafness from an acquired hearing deficit. The initial aim of the study was to research the frequency of the congenital cochlear hearing loss among patients with various gene defects resulting in mitochondrial disorders. The research process brought on an additional gain: basing on our preliminary study group of 80 patients, in 12 patients altogether we identified two defected genes responsible for mitochondrial disorders, whose carriers did not pass the NHSP. Finally, these patients were diagnosed with the congenital cochlear deafness.

Material And Methods: The results of the NHSP in the patients with mitochondrial disorders diagnosed in our tertiary reference center were analyzed. Only the cases with confirmed mutations were qualified for the study group. The NHSP database included 80 patients with mutations in 31 different genes: 25 nuclear-encoded and 6 mtDNA-encoded. We searched the literature for the presence of a congenital hearing impairment (CHI) in mitochondrial disorders caused by changes in 278 already known genes.

Results: For 68 patients from the study group the NHSP test indicated a proper cochlear function and thus suggested normal hearing. For 12 mitochondrial patients, the NHSP test indicated the requirement for the further audiological diagnosis, and finally CHI was confirmed in 8 of them. This latter subset included patients with pathogenic variants in RRM2B and SERAC1, known as "deafness-causing genes". Contrary to our initial expectations, the patients carrying mutations in other "deafness-causing genes": MPV17, POLG, COX10, as well as other mitochondria-related genes, all reported in literature, did not indicate any CHI following the NHSP test.

Conclusion: Our study indicates that the cochlear CHI is a phenotypic feature of the RRM2B and SERAC1 related defects. The diagnosis of the CHI following the NHSP allows to early distinguish those defects from other mitochondria-related disorders in which the NHSP test result is correct. Wider studies are needed to assess the significance of this observation.

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.ijporl.2019.03.015DOI Listing

Publication Analysis

Top Keywords

congenital cochlear
20
mitochondrial disorders
16
rrm2b serac1
12
study group
12
nhsp test
12
patients
11
nhsp
9
cochlear deafness
8
gene defects
8
mitochondrial patients
8

Similar Publications

The Canadian Association of Radiologists (CAR) Central Nervous System Expert Panel is made up of physicians from the disciplines of radiology, emergency medicine, neurosurgery, and neurology, a patient advisor, and an epidemiologist/guideline methodologist. After developing a list of 24 clinical/diagnostic scenarios, a rapid scoping review was undertaken to identify systematically produced referral guidelines that provide recommendations for one or more of these clinical/diagnostic scenarios. Recommendations from 55 guidelines and contextualization criteria in the Grading of Recommendations, Assessment, Development, and Evaluations (GRADE) for guidelines framework were used to develop 51 recommendation statements across the 24 scenarios.

View Article and Find Full Text PDF

Mutations in the human genes encoding the endothelin ligand-receptor pair and cause Waardenburg-Shah syndrome (WS4), which includes congenital hearing impairment. The current explanation for auditory dysfunction is defective migration of neural crest-derived melanocytes to the inner ear. We explored the role of endothelin signaling in auditory development in mice using neural crest-specific and placode-specific mutation plus related genetic resources.

View Article and Find Full Text PDF

Introduction: Despite improved hearing, children who receive cochlear implants (CIs) at a later age encounter difficulties in adapting to society, exposing them to psychological and social risks. This study contributes to the conceptualisation of preventive interventions in schools to address potential issues so that these children can play a more active role in society.

Methods: A total of 52 children (aged 3-12 years) who received CIs at 30 months of age were assessed using the Asahide-Shiki Social Adaptive skills test, which evaluates children's social skills on four domains: (A) language, (B) everyday life, (C) social life, (D) communication.

View Article and Find Full Text PDF

Newborn screening for common genetic variants associated with permanent hearing loss: Implementation in Ontario and a review of the first 3 years.

Genet Med

January 2025

Newborn Screening Ontario, Children's Hospital of Eastern Ontario, Ottawa, ON, Canada; Children's Hospital of Eastern Ontario Research Institute, University of Ottawa, Ottawa. Electronic address:

Purpose: Universal newborn hearing screening (UNHS) programs using audiometric techniques alone are limited in ability to detect non-congenital childhood permanent hearing loss (PHL). In 2019, Ontario launched universal newborn screening (NBS) for PHL risk factors: congenital cytomegalovirus (cCMV) and 22 common variants in GJB2 and SLC26A4. Here we describe our experience with genetic risk factor screening.

View Article and Find Full Text PDF

Genotypes and clinical phenotypes of pediatric patients with NOG variants: Middle ear surgical outcomes from a Tertiary Center in South Korea.

Int J Pediatr Otorhinolaryngol

January 2025

Department of Otorhinolaryngology-Head and Neck Surgery, College of Medicine, Seoul National University Hospital, Seoul, Republic of Korea; Sensory Organ Research Institute, Seoul National University, Medical Research Center, Seoul, Republic of Korea. Electronic address:

Objective: Although NOG variants are linked to congenital stapes fixation and conductive hearing loss (CHL), little is known about middle ear surgery outcomes and the characteristics of accompanying inner ear anomalies. We explored auditory phenotypes in patients with NOG variants, with a focus on the outcomes of middle ear surgery.

Methods: This study included 11 patients from five unrelated Korean families harboring NOG variants.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!