Hearing loss in osteogenesis imperfecta: characteristics and treatment considerations

Annual hearing screening in children with osteogenesis imperfecta: Results from the first five years in glasgow

BACKGROUND

Hearing loss is common in people with osteogenesis imperfecta (OI), although exactly how common is unknown. The prevalence of hearing loss in children with OI has been reported to be anything from 0 to 77 %. Brittle Bone Society guidelines suggest that, unless there are ear symptoms, children with OI should have their hearing tested every three years starting at age three. There is limited evidence to support this recommendation. We postulate that annual hearing screening would be easier to manage and would have a worthwhile pick-up rate.

METHODS

In March 2019 we began a programme of annual hearing screening for all children (ages 0-16) with OI. We collected data on age, genotype, otoscopy findings, tympanometry findings, audiometric test results and subsequent outcomes for the first five years of our programme (2019-2024).

RESULTS

Nineteen children with OI participated in the screening programme. Only one abnormality was found: a unilateral mild hearing impairment with a type B tympanogram, suggesting middle ear effusion. This was present in year 2 of the programme but resolved by year 3.

CONCLUSION

The screening programme has a low pickup rate (5 %) for new otological problems in the paediatric population. However, we believe that the low cost and small workload associated with the screening programme justifies continuing it until further conclusions can be drawn.

A Consolidated Understanding of the Contribution of Redox Dysregulation in the Development of Hearing Impairment

The etiology of hearing impairment is multifactorial, with contributions from both genetic and environmental factors. Although genetic studies have yielded valuable insights into the development and function of the auditory system, the contribution of gene products and their interaction with alternate environmental factors for the maintenance and development of auditory function requires further elaboration. In this review, we provide an overview of the current knowledge on the role of redox dysregulation as the converging factor between genetic and environmental factor-dependent development of hearing loss, with a focus on understanding the interaction of oxidative stress with the physical components of the peripheral auditory system in auditory disfunction. The potential involvement of molecular factors linked to auditory function in driving redox imbalance is an important promoter of the development of hearing loss over time.

Morphological variability in the inner ear of mice with osteogenesis imperfecta

Osteogenesis imperfecta (OI) is known to cause hearing loss in ~60% of the affected human population. While OI-related pathologies have been studied in the middle ear, the development of cochlear pathologies is less well understood. In this study, we examine OI-related pathologies of the cochlea in a mouse model of OI to (1) document variation between OI and unaffected mice, and (2) assess the intrusion of the otic capsule onto the cochlea by analyzing differences in duct volumes. Juvenile and adult OIM C57BL/6mice were compared to unaffected wildtype (WT) mice using three-dimensional models of the cochlea generated from high resolution micro-CT scans. Two-tailed Mann-Whitney U tests were then used to investigate duct volume differences both within and between the OI and WT samples. Areas of higher ossification were observed at the cochlear base in the OI sample. OI mice also had significant intraindividual differences in duct volume between right and left ears (4%-15%), an effect not observed in WT mice. WT and OI duct volumes showed a large degree of overlap, although the OIM volumes were more variable. Our findings indicate that OIM mice are likely to exhibit more asymmetry and variation in cochlear volume despite minor differences in sample cochlear volumes, possibly due to bony capsule intrusion. This suggests a potential mechanism of hearing loss, and a high potential for cochlear and otic capsule alteration in OIM mice.

Medical Care Use Among Patients with Monogenic Osteoporosis Due to Rare Variants in LRP5, PLS3, or WNT1

Pathogenic variants in the LRP5, PLS3, or WNT1 genes can significantly affect bone mineral density, causing monogenic osteoporosis. Much remains to be discovered about the phenotype and medical care needs of these patients. The purpose of this study was to examine the use of medical care among Dutch individuals identified between 2014 and 2021 with a pathogenic or suspicious rare variant in LRP5, PLS3, or WNT1. In addition, the aim was to compare their medical care utilization to both the overall Dutch population and the Dutch Osteogenesis Imperfecta (OI) population. The Amsterdam UMC Genome Database was used to match 92 patients with the Statistics Netherlands (CBS) cohort. Patients were categorized based on their harbored variants: LRP5, PLS3, or WNT1. Hospital admissions, outpatient visits, medication data, and diagnosis treatment combinations (DTCs) were compared between the variant groups and, when possible, to the total population and OI population. Compared to the total population, patients with an LRP5, PLS3, or WNT1 variant had 1.63 times more hospital admissions, 2.0 times more opened DTCs, and a greater proportion using medication. Compared to OI patients, they had 0.62 times fewer admissions. Dutch patients with an LRP5, PLS3, or WNT1 variant appear to require on average more medical care than the total population. As expected, they made higher use of care at the surgical and orthopedic departments. Additionally, they used more care at the audiological centers and the otorhinolaryngology (ENT) department, suggesting a higher risk of hearing-related problems.

[Features and results of surgical rehabilitation of hearing loss in osteogenesis imperfecta]

Osteogenesis imperfecta (OI) is a form of congenital osteoporosis. Depending on the type of OI, patients experience various types of hearing loss. Depending on the type and degree of hearing loss, various methods of hearing rehabilitation are used in this category of patients.

OBJECTIVE

To evaluate the features and results of surgical rehabilitation of hearing loss in patients with osteogenesis imperfecta.

MATERIAL AND METHODS

During the period from 2009 to 2022, 2221 primary stapedoplasty was performed in the department, of which 23 (1.04%) in 21 patients were performed in patients with OI. There were 14 women and 7 men. According to TPA, bilateral hearing loss was detected in 19 patients and unilateral in 2. Conductive hearing loss was observed in 9 cases and mixed - in 14. The average thresholds for bone conduction (BC) were 22.7±8.04 dB, and the bone-air interval (ABG) - 36.1±5.3 dB. According to CT of the temporal bones, all patients showed a bilateral and symmetrical decrease in the density of the auditory ossicles, and in 7 patients there were extensive areas of non-uniform decrease in the density of the bone labyrinth up to +500 - +1000 HU.21 patients underwent 23 operations: in 21 cases stapedoplasty with laser assistance and in 2 cases ossiculoplasty.

RESULTS

BC thresholds 6 months after surgery averaged 24.6±8.2 dB, and ABG - 12.1±2.9 dB. Closing of ABG ≤10 dB at spoken frequencies was detected in 30.5%, ABG ≤20 dB - in 95%. After 12 months or more after the operation, no change in the audiological parameters was noted.

CONCLUSIONS

Stapes surgery for conductive and mixed hearing loss in OI patients is functionally effective. The best results are achieved after therapy with bisphosphonates with preparations of sodium fluoride, calcium and vitamin D, performing the operation when the density of demineralization zones reaches 1000 HU and using laser assistance. Taking into account the demineralization of the bone structures of the temporal bone, it is recommended to use autocartilaginous stirrup prostheses to restore sound conduction or to cover the attachment area of other prostheses with autologous tissues to prevent necrosis of the long stalk of the incus and stabilize long-term functional results.

Treatments for hearing loss in osteogenesis imperfecta: a systematic review and meta-analysis on their efficacy

About 70% of people with osteogenesis imperfecta (OI) experience hearing loss. There is no cure for OI, and therapies to ameliorate hearing loss rely on conventional treatments for auditory impairments in the general population. The success rate of these treatments in the OI population with poor collagenous tissues is still unclear. Here, we conduct a systematic review and meta-analysis on the efficacy of treatments addressing hearing loss in OI. This study conforms to the reporting standards of the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA). Data sources include published articles in Medline via PubMed, Web of Science, Scopus, and Embase, from their inception to November 2020. Studies included individuals with OI undergoing a hearing loss treatment, having pre- and postoperative objective assessment of hearing function at a specified follow-up length. Our search identified 1144 articles, of which 67 were reviewed at full-text screening. A random-effects meta-analysis was conducted on the selected articles (n = 12) of people with OI that underwent stapes surgery. Success was assessed as the proportion of ears with a postoperative Air-Bone Gap (ABG) ≤ 10 dB. A systematic review was conducted on the remaining articles (n = 13) reporting on other treatments. No meta-analysis was conducted on the latter due to the low number of articles on the topic and the nature of single case studies. The meta-analysis shows that stapes surgeries have a low success rate of 59.08 (95% CI 45.87 to 71.66) in the OI population. The systematic review revealed that cochlear implants, bone-anchored hearing aids, and other implantable hearing aids proved to be feasible, although challenging, in the OI population, with only 2 unsuccessful cases among the 16 reviewed single cases. This analysis of published data on OI shows poor clinical outcomes for the procedures addressing hearing loss. Further studies on hearing loss treatments for OI people are needed. Notably, the mechanisms of hearing loss in OI need to be determined to develop successful and possibly non-invasive treatment strategies.

Prevention of Hypomineralization In Auditory Ossicles of Vitamin D Receptor (Vdr) Deficient Mice

Intact mineralization of the auditory ossicles - the smallest bones in the body - is essential for sound transmission in the middle ear, while ossicular hypomineralization is associated with conductive hearing loss. Here, we performed a high-resolution analysis of the ossicles in vitamin D receptor deficient mice (Vdr^-/- ), which are characterized by hypocalcemia and skeletal mineralization defects, and investigated whether local hypomineralization can be prevented by feeding a calcium-rich rescue diet (Vdr^{-/- res} ). In Vdr^-/- mice fed a regular diet (Vdr^{-/- reg} ), quantitative backscattered electron imaging (qBEI) revealed an increased void volume (porosity, p<0.0001) along with lower mean calcium content (CaMean, p=0.0008) and higher heterogeneity of mineralization (CaWidth, p=0.003) compared to WT mice. Furthermore, a higher osteoid volume per bone volume (OV/BV; p=0.0002) and a higher osteocyte lacunar area (Lc.Ar; p=0.01) were found in histomorphometric analysis in Vdr^{-/- reg} mice. In Vdr^{-/- res} mice, full rescue of OV/BV and Lc.Ar (both p>0.05 vs. WT) and partial rescue of porosity and CaWidth (p=0.02 and p=0.04 vs. WT) were observed. Compared with Hyp mice, a model of X-linked hypophosphatemic rickets, Vdr^{-/- reg} mice showed a lower osteoid volume in the ossicles (p=0.0002), but similar values in the lumbar spine. These results are consistent with later postnatal impairment of mineral homeostasis in Vdr^-/- mice than in Hyp mice, underscoring the importance of intact mineral homeostasis for ossicle mineralization during development. In conclusion, we revealed a distinct phenotype of hypomineralization in the auditory ossicles of Vdr^-/- mice that can be partially prevented by a rescue diet. Since a positive effect of a calcium-rich diet on ossicular mineralization was demonstrated, our results open new treatment strategies for conductive hearing loss. Future studies should investigate the impact of improved ossicular mineralization on hearing function.

Oral health-related quality of life in children with osteogenesis imperfecta

Purpose

Osteogenesis imperfecta (OI) results from mutations in the genes involved in the modification or biosynthesis of collagen. This study aimed to assess the oral health-related quality of life (OHRQoL) in children with OI.

Methodology

Participants were recruited from a highly specialised OI centre for children. The Child Oral-Health Impact Profile—Short Form (COHIP-SF) was used, adding demographic and qualitative questions. Children aged 8–16 years participated between January and October 2019. Statistical analysis was carried out. A higher COHIP-SF score indicates better OHRQoL (maximum score, 76).

Results

One hundred and six (106) children participated (44 female, mean age 11.93 years). COHIP-SF median score was 59. Children reporting mild OI (n = 55) had higher median scores (62) compared to severe OI (n = 7) with median scores of 55 (P = 0.087). When comparing mixed (< 12 years, n = 46) and permanent dentition (≥ 12, n = 60), no significant difference in OHRQoL was seen (P = 0.977). There was no significant difference between severities for each COHIP-SF domain. Limited data on the presence of dentinogenesis imperfecta did not impact overall score (P = 0.109), but was significant in the oral-health domain (P = 0.033).

Qualitative

Common themes were the need for braces, discolouration, pain and function.

Conclusion

This study confirmed that children with OI have dental concerns in areas including oral health, functional well-being and socio-emotional well-being. This was related to severity of OI.

[The experience in surgical treatment of hearing loss in Van der Hoeve patients]

Despite the rare incidence of Van der Hoeve syndrome in the population, the problem of treating patients with this type of disease is important for modern science and practical medicine. One of the most difficult tasks in treatment is to improve the quality of hearing. The world scientific community lacks a unified coordinated approach to the methods of auditory rehabilitation of patients with Van der Hoeve syndrome. In recent years, there have been tendencies in the scientific literature to increase the frequency of non-surgical approach due to the low incidence of satisfactory results of surgical treatment. In this regard, we present our experience of complex treatment of patients with Van der Hove syndrome, based on the use of modern surgical technologies and conservative pathogenetically substantiated treatment.

The Anesthetic Management of a Parturient With Osteogenesis Imperfecta Type I Undergoing Cesarean Delivery

Osteogenesis imperfecta (OI) is a rare disorder of bone fragility caused by mutations in the COL1A1/2 genes, which encode type I procollagen. It commonly manifests with bone fractures, joint dislocations, and easy bruising. OI patients presenting for surgery may pose multiple challenges to the anesthesiologist such as management of a potentially difficult airway and heightened positional fracture risks. We present a case detailing the spinal anesthetic management of a 28-year-old woman with type I OI requiring cesarean delivery for a 32-week intrauterine pregnancy with fetal cardiac anomalies.

Inter- and Intrafamilial Phenotypic Variability in Individuals with Collagen-Related Osteogenesis Imperfecta

Osteogenesis imperfecta (OI) is a rare genetic disorder also known as a “brittle bone disease.” Around 90% of patients with OI harbor loss‐of‐function or dominant negative pathogenic variants in the COL1A1 and COL1A2 genes, which code for collagen type I α1 and α2 chains. Collagen‐related forms of the disorder are classified as Sillence OI types I–IV. OI phenotype expression ranges from mild to lethal. The current study aims to evaluate associations between interfamilial and intrafamilial phenotypic variability and genotype characteristics of patients with collagen‐related OI. The study was based on a systematic review of collagen‐related OI cases from the University of Tartu OI database (n = 137 individuals from 81 families) and the Dalgleish database (n = 479 individuals). Interfamilial variability analysis has shown that 17.74% of all studied OI‐related variants were associated with the same phenotype. The remaining 82.26% of pathogenic variants were associated with variable phenotypes. Additionally, higher interfamilial variability correlated with the COL1A1 gene (P value = 0.001) and dominant‐negative variants (P value = 0.0007). Within intrafamilial variability, 32.81% families had increasing or decreasing OI phenotype severity across generations. Higher intrafamilial variability of phenotypes correlated with the collagen I dominant negative variants (P value = 0.0246). The current study shows that, in line with other phenotype modification factors, OI interfamilial and intrafamilial diversity potential is associated with the genotype characteristics of the OI‐causing pathogenic variants. The results of the current study may advance knowledge of OI phenotype modification as well as assist family planning and the evaluation of disease progression in subsequent generations.

Genotype-phenotype relationship in a large cohort of osteogenesis imperfecta patients with COL1A1 mutations revealed by a new scoring system

BACKGROUND

Osteogenesis imperfecta (OI), a heritable bone fragility disorder, is mainly caused by mutations in COL1A1 gene encoding α1 chain of type I collagen. This study aimed to investigate the COL1A1 mutation spectrum and quantitatively assess the genotype-phenotype relationship in a large cohort of Chinese patients with OI.

METHODS

A total of 161 patients who were diagnosed as OI in Department of Endocrinology of Peking Union Medical College Hospital from January 2010 to December 2017 were included in the study. The COL1A1 mutation spectrum was identified by next generation sequencing and confirmed by Sanger sequencing. A new clinical scoring system was developed to quantitatively assess the clinical severity of OI and the genotype-phenotype relationship was analyzed. The independent sample t-test, analysis of variance, Mann-Whitney U-test, Chi-squared test, Pearson correlation, and multiple linear regression were applied for statistical analyses.

RESULTS

Among 161 patients with OI, 32.9% missense mutations, 16.8% non-sense mutations, 24.2% splice-site mutations, 24.8% frameshift mutations, and 1.2% whole-gene deletions were identified, of which 38 variations were novel. These mutations led to 53 patients carrying qualitative defects and 67 patients carrying quantitative defects in type I collagen. Compared to patients with quantitative mutations, patients with qualitative mutations had lower alkaline phosphatase level (296 [132, 346] U/L vs. 218 [136, 284] U/L, P = 0.009) and higher clinical score (12.2 ± 5.3 vs. 7.4 ± 2.4, P < 0.001), denoting more severe phenotypes including shorter stature, lower bone mineral density, higher fracture frequency, more bone deformity, vertebral compressive fractures, limited movement, and dentinogenesis imperfecta (DI). Patients would not present with DI if the glycine substitutions happened before the 79th amino acid in triple helix of α1 chains.

CONCLUSIONS

This presented distinctive COL1A1 mutation spectrum in a large cohort of Chinese patients with OI. This new quantitative analysis of genotype-phenotype correlation would be helpful to predict the prognosis of OI and genetic counseling.

Incorporating the patient perspective in the study of rare bone disease: insights from the osteogenesis imperfecta community

There is limited research which examines health concerns of individuals with osteogenesis imperfecta (OI). Discussion groups with leaders of the adult OI community identified a broad range of medical priorities beyond fractures and brittle bones. Our work underscores the need to include patient-reported outcomes in rare bone disease research.

INTRODUCTION

Osteogenesis imperfecta (OI) is a rare genetic disorder affecting collagen protein leading to brittle bones and a number of other medical complications. To date, there is limited research which examines the life-long process of aging with this rare disease, much less the perspective of individuals with OI.

METHODS

In order to explore and prioritize health concerns that adults with OI feel have been inadequately addressed in health care and research, investigators held discussions with leaders from the global adult OI community. The meetings were held in August 2017 at the 13th International Conference on OI in Oslo, Norway as part of the preconference seminar "Patient Participation in OI Research". Investigators were part of the Brittle Bone Disease Consortium (BBDC), a multicenter research program devoted to the study of OI, and their focus was on patient-reported outcomes (PRO).

RESULTS

Participants noted that while fractures and brittle bones are the most common feature of OI, a number of body systems are under-studied in this disorder. They particularly emphasized breathing, hearing, and the effects of aging as primary concerns that researchers and physicians may not fully understand or address. Other areas included pain, gastrointestinal problems, mental health, nutrition, menopause/pregnancy, and basilar invagination. Participants also emphasized that they must be informed of study results. They underscored that outcome measures incorporated into future drug trials must look beyond fractures and consider the whole patient.

CONCLUSIONS

This work will help guide the incorporation of PROs into the next phase of the BBDC Natural History Study of OI and underscores the importance of including PROs in the study of rare diseases.

Temporal Bone Imaging Features in Osteogenesis Imperfecta

We present the case of a 33-year old woman with osteogenesis imperfecta (OI) with progressive hearing loss and persisting vertigo. On CT-scan, symmetric extensive lucency in the pericochlear bony otic capsule and promontorium was demonstrated. The MRI-scan demonstrated symmetric areas of increased signal intensity on the T2-images with moderate contrast enhancement in the same regions. These findings correlate histologically by undermineralized thickened bone, the hallmark of OI. Hearing loss is an important clinical feature in patients with OI. The value of temporal bone imaging lies in additional confirmation of the diagnosis, determining the extent disease and excluding concomitant pathology.

Endocrine Glands and Hearing: Auditory Manifestations of Various Endocrine and Metabolic Conditions

The aetiology of hearing loss in humans is multifactorial. Besides genetic, environmental and infectious causes, several endocrine and metabolic abnormalities are associated with varying degrees of hearing impairment. The pattern of hearing loss may be conductive, sensori-neural or mixed. The neurophysiology of hearing as well as the anatomical structure of the auditory system may be influenced by changes in the hormonal and metabolic milieu. Optimal management of these conditions requires the integrated efforts of the otolaryngologist and the endocrinologist. The presence of hearing loss especially in the young age group should prompt the clinician to explore the possibility of an associated endocrine or metabolic disorder for timely referral and early initiation of treatment.

Phenotypic variability of osteogenesis imperfecta type V caused by an IFITM5 mutation

In a large cohort of osteogenesis imperfecta type V (OI type V) patients (17 individuals from 12 families), we identified the same mutation in the 5' untranslated region (5'UTR) of the interferon-induced transmembrane protein 5 (IFITM5) gene by whole exome and Sanger sequencing (IFITM5 c.-14C > T) and provide a detailed description of their phenotype. This mutation leads to the creation of a novel start codon adding five residues to IFITM5 and was recently reported in several other OI type V families. The variability of the phenotype was quite large even within families. Whereas some patients presented with the typical calcification of the forearm interosseous membrane, radial head dislocation and hyperplastic callus (HPC) formation following fractures, others had only some of the typical OI type V findings. Thirteen had calcification of interosseous membranes, 14 had radial head dislocations, 10 had HPC, 9 had long bone bowing, 11 could ambulate without assistance, and 1 had mild unilateral mixed hearing loss. The bone mineral density varied greatly, even within families. Our study thus highlights the phenotypic variability of OI type V caused by the IFITM5 mutation.