Anne M M Oonk1, Merel S Ekker2, Patrick L M Huygen3, Henricus P M Kunst3, Hannie Kremer4, Jurgen J Schelhaas5, Ronald J E Pennings3. 1. Department of Otorhinolaryngology, Hearing & Genes, Radboud University Medical Centre, Nijmegen, the Netherlands Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Centre, Nijmegen, the Netherlands Anne.Oonk@Radboudumc.nl. 2. Department of Otorhinolaryngology, Hearing & Genes, Radboud University Medical Centre, Nijmegen, the Netherlands. 3. Department of Otorhinolaryngology, Hearing & Genes, Radboud University Medical Centre, Nijmegen, the Netherlands Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Centre, Nijmegen, the Netherlands. 4. Department of Otorhinolaryngology, Hearing & Genes, Radboud University Medical Centre, Nijmegen, the Netherlands Nijmegen Centre for Molecular Life Sciences, Radboud University Medical Centre, Nijmegen, the Netherlands. 5. Expertise Centre for Epileptology, Sleep Medicine and Neurocognition, Kempenhaege, Heeze, the Netherlands.
Abstract
OBJECTIVE: Mutations in the transient receptor potential vanilloid 4 gene (TRPV4) can induce a great diversity of neuropathies. Together with these neuropathies, hearing loss can occur. This study is focused on providing an audiometric phenotype description of a Dutch family with spinal muscular atrophy caused by a mutation in TRPV4. METHODS: A neurological examination was repeated and pure tone and speech audiometry were performed. RESULTS: A large variety in neurological symptoms as well as variation in audiometric characteristics was observed. The severity of hearing loss is mild to moderate and the audiogram configuration is highly variable. The hearing loss of these patients has a progressive nature in general. The frequencies that deteriorate significantly differ between family members. When compared to presbyacusis patients, speech recognition scores of patients with a TRPV4 mutation are not clearly different. CONCLUSION: The function of TRPV4 in the inner ear is still elusive but it is suggested that TRPV4 is required for maintenance of cochlear function in stress conditions, like acoustic injury. We can neither confirm nor reject this based on the results obtained in this family. Therefore, one might consider advising patients with a TRPV4 mutation to avoid exposure to environmental influences such as noise exposure.
OBJECTIVE: Mutations in the transient receptor potential vanilloid 4 gene (TRPV4) can induce a great diversity of neuropathies. Together with these neuropathies, hearing loss can occur. This study is focused on providing an audiometric phenotype description of a Dutch family with spinal muscular atrophy caused by a mutation in TRPV4. METHODS: A neurological examination was repeated and pure tone and speech audiometry were performed. RESULTS: A large variety in neurological symptoms as well as variation in audiometric characteristics was observed. The severity of hearing loss is mild to moderate and the audiogram configuration is highly variable. The hearing loss of these patients has a progressive nature in general. The frequencies that deteriorate significantly differ between family members. When compared to presbyacusis patients, speech recognition scores of patients with a TRPV4 mutation are not clearly different. CONCLUSION: The function of TRPV4 in the inner ear is still elusive but it is suggested that TRPV4 is required for maintenance of cochlear function in stress conditions, like acoustic injury. We can neither confirm nor reject this based on the results obtained in this family. Therefore, one might consider advising patients with a TRPV4 mutation to avoid exposure to environmental influences such as noise exposure.