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Hearing loss in biotinidase deficiency: genotype-phenotype correlation
Hatice Serap Kalkanoğlu Sivri1, Gülsüm Aydan Genç, Ayşegül Tokatli
1Hacettepe University, Department of Pediatrics, Nutrition & Metabolism Unit, Ankara, Turkey.
The Journal of Pediatrics
|March 27, 2007
Summary
Children with biotinidase deficiency and null mutations face a higher risk of hearing loss. Early treatment after birth can prevent hearing loss in these children, even with null mutations.
Area of Science:
- Genetics
- Pediatrics
- Audiology
Background:
- Biotinidase deficiency is an inherited metabolic disorder.
- Hearing loss is a common symptom of untreated biotinidase deficiency.
- Genetic mutations in the BTD gene cause biotinidase deficiency.
Purpose of the Study:
- To compare the risk of hearing loss in children with different types of biotinidase deficiency mutations.
- To determine the impact of treatment timing on hearing loss prevention in null mutation cases.
Main Methods:
- Retrospective analysis of patient data.
- Comparison of hearing outcomes based on mutation type (null vs. missense).
- Evaluation of treatment initiation timing and its correlation with hearing preservation.
Main Results:
- Children with null mutations showed a higher incidence of hearing loss compared to those with missense mutations.
- Hearing loss developed even in some treated patients if treatment was delayed.
- Prompt treatment initiation shortly after birth was associated with the prevention of hearing loss in null mutation cases.
Conclusions:
- Mutation type significantly influences the risk of hearing loss in biotinidase deficiency.
- Early diagnosis and timely treatment are crucial for preventing hearing loss in infants with biotinidase deficiency, particularly those with null mutations.
- Genetic screening and newborn screening programs are vital for early intervention.
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