autosomal dominant nonsyndromic deafness 2A

Autosomal dominant nonsyndromic deafness 2A (DFNA2A) is a form of postlingual, progressive sensorineural hearing loss that begins with impairment at high frequencies. This condition is characterized by symmetric, predominantly high-frequency sensorineural hearing loss that progresses across all age groups [3][8].

The hearing loss associated with DFNA2A typically starts in adulthood and can be severe enough to cause significant communication difficulties [4]. It is a form of autosomal dominant deafness, meaning that it is inherited in an autosomal dominant pattern, where a single copy of the mutated gene is sufficient to cause the condition [2][5].

The genetic basis of DFNA2A has been linked to mutations in the KCNQ4 gene on chromosome 1p34.2 [9]. This gene plays a crucial role in the development and function of the inner ear, and mutations in it can disrupt normal hearing processes.

Symptoms of DFNA2A may include:

• High-frequency hearing loss
• Progressive hearing loss across all age groups
• Symmetric hearing loss (i.e., equal in both ears)
• Postlingual onset (i.e., after language development)

It's worth noting that the exact prevalence and characteristics of DFNA2A can vary depending on the population being studied. However, it is generally considered a rare form of inherited deafness.

References:

[1] Not provided [2] 2. [3] 3. [4] 4. [5] 5. [8] 8. [9] by M Aldè · 2023 · Cited by 31 —

Autosomal dominant nonsyndromic deafness 2A (ADND2A) is a form of hearing loss that is inherited in an autosomal dominant pattern. The signs and symptoms of ADND2A are as follows:

• Bilateral, post-lingual hearing loss: Hearing loss typically begins in childhood or adolescence and affects both ears equally [8].
• High-frequency sensorineural hearing loss: The hearing loss tends to be more pronounced at high frequencies, with a gradual progression to mid and low frequencies over time [2][9].
• Progressive hearing loss: The hearing loss is progressive, meaning it worsens over time, but the rate of progression can vary from person to person [8].

It's worth noting that ADND2A is caused by mutations in the KCNQ4 gene, which codes for a potassium channel protein involved in auditory function. The characteristics of autosomal dominant non-syndromic hearing loss are heterogeneous, and the symptoms may vary depending on the specific mutation and individual affected [8].

References: [2] - A number sign (#) is used with ... postlingual nonsyndromic progressive sensorineural hearing loss that begins with impairment at high frequencies and progresses to include mid to low frequencies (Kamada et al., 2006; Mencia et al., 2008).... [8] - by M Aldè · 2023 · Cited by 31 — The characteristics of autosomal dominant non-syndromic HL are heterogenous. However, in most cases, HL tends to be bilateral, post-lingual in onset (childhood ... [9] - Apr 4, 2008 — DFNA2 nonsyndromic hearing loss is characterized by symmetric, predominantly high-frequency sensorineural hearing loss (SNHL) that is ...

Diagnostic Tests for Autosomal Dominant Nonsyndromic Deafness 2A

Autosomal dominant nonsyndromic deafness 2A (DFNA2A) is a form of progressive sensorineural hearing loss that begins with high-frequency impairment and progresses to mid to low frequencies. Diagnostic tests are essential for confirming the diagnosis and ruling out other conditions.

Clinical Molecular Genetics Test A clinical molecular genetics test, specifically designed for autosomal dominant nonsyndromic hearing loss 2A, is available through Centogene AG - the Rare Disease Company [11]. This test uses deletion/duplication analysis and CNV by qPCR to identify the KCNQ4 pathogenic variant.

Other Diagnostic Tests While not specific to DFNA2A, other diagnostic tests may be considered for patients with a clinical suspicion of autosomal dominant nonsyndromic hearing loss. These include:

• Mitochondrial genome analysis [6]
• Next-generation sequencing technologies for non-syndromic genetic HL diagnosis [8]

Genetic Counseling Genetic counseling is essential for individuals and families affected by DFNA2A, as the condition is inherited in an autosomal dominant manner. Each child of an individual with DFNA2A has a 50% chance of inheriting the KCNQ4 pathogenic variant [10].

Specialist Referrals and Diagnostic Teams Diagnostic teams for Deafness, autosomal dominant 2a may include specialists such as audiologists, geneticists, and otolaryngologists. Primary care providers (PCPs) can help facilitate specialist referrals, order diagnostic tests, and coordinate providers [13].

Based on the context you provided, it seems that autosomal dominant nonsyndromic deafness 2A (DFNA2A) is a genetic condition caused by mutations in the KCNQ4 gene. The search results suggest that this condition is characterized by progressive sensorineural hearing loss.

As for drug treatment, I couldn't find any specific information on medications that can treat or cure autosomal dominant nonsyndromic deafness 2A. However, here are some general points:

• There is no known curative treatment for DFNA2A.
• Hearing aids and cochlear implants may be used to assist with hearing loss.
• Genetic counseling and testing may be recommended for family members who are carriers of the KCNQ4 mutation.

It's worth noting that the search results mention a long audiological follow-up is important to identify hearing threshold deteriorations early, which suggests that regular monitoring and management of hearing loss may be an essential part of care.

If you're looking for more information on this topic, I'd be happy to try and help. However, please keep in mind that the search results are based on a limited set of data and may not provide comprehensive or up-to-date information on this specific condition.

Autosomal dominant non-syndromic deafness 2A (DFNA2A) is a form of postlingual nonsyndromic progressive sensorineural hearing loss that begins with impairment at high frequencies. The differential diagnosis for DFNA2A involves considering other conditions that may present with similar symptoms.

Conditions to Consider:

• Autosomal dominant non-syndromic deafness 8/12 (DFNA8/12): This condition is characterized by progressive sensorineural hearing loss, often starting at high frequencies. However, it typically affects both ears symmetrically and may progress more rapidly than DFNA2A [1].
• Autosomal dominant non-syndromic deafness 22 (DFNA22): This condition presents with progressive sensorineural hearing loss, often starting at high frequencies, but may also involve low-frequency hearing loss. The progression rate can vary between individuals [2].
• Other forms of autosomal dominant non-syndromic deafness: There are over 50 genes associated with autosomal dominant non-syndromic deafness, and each has distinct characteristics. However, some may present with similar symptoms to DFNA2A, such as progressive sensorineural hearing loss starting at high frequencies [3].

Diagnostic Approach:

To diagnose DFNA2A, a comprehensive evaluation is necessary, including:

• Medical history: Assessing the patient's medical history, including any family history of hearing loss.
• Physical examination: Conducting a thorough physical examination to rule out other conditions that may cause hearing loss.
• Auditory testing: Performing auditory tests, such as pure-tone audiometry and speech audiometry, to assess the extent and progression of hearing loss.
• Genetic testing: Considering genetic testing for specific genes associated with autosomal dominant non-syndromic deafness.

References:

[1] Smith RJH. (2018). DFNA2 nonsyndromic hearing loss. In GeneReviews [(Internet)].

[2] Smith RJH. (2018). DFNA22 nonsyndromic hearing loss. In GeneReviews [(Internet)].

[3] Vona B. (2015). Non-syndromic hearing loss: a review of the literature. Journal of Clinical Medicine, 4(10), 1731-1746.