Bleeding assessment in a large cohort of patients with Osteogenesis Imperfecta.

BACKGROUND: Osteogenesis Imperfecta (OI) is characterised by bone fragility. Among several features, easy bruising and multiple case reports on haemorrhagic events have been reported. This paper describes the diverse manifestations of bleeding and bruising in a large cohort of 328 OI patients. The aim of this study is to provide insight in the diverse aspects and therapeutic considerations of bleedings in OI. METHODS: This descriptive cohort study was conducted at the National Expert Center for adults with OI in the Netherlands. Bleeding was assessed by the validated self-bleeding assessment tool (Self-BAT) The tool was distributed among 328 adults with different clinically confirmed types of OI. RESULTS: 195 of 328 invited patients (completion rate 60%) with OI type 1 (n = 144), OI type 3 (n = 17) and OI type 4 (n = 34), aged between 18 and 82 years, completed the tool. Self-BAT scores were above the normal range in 42% of all patients. For males Self-BAT scores were increased in 37% with a mean score of 3.7, ranged between 0 and 18. For females the Self-BAT scores were increased in 44% with a mean of 5.4 and a range of 0-24. No statistical differences in OI subtypes were found. CONCLUSIONS: Bleeding tendency appears to be a relevant complication in OI patients as this study confirms the presumption of bleeding tendency. There are specific recommendations to clinicians who treat OI patients to consider an assessment of bleeding tendency and use potential interventions to reduce haemorrhagic complications and improve quality of life.

A Baseline Measurement of Quality of Life in 322 Adults With Osteogenesis Imperfecta.

Osteogenesis imperfecta (OI) is characterized by bone fragility and secondary features such as blue sclerae, dentinogenesis imperfecta, hearing loss, ligamentous laxity, and short stature. It was thought that health-related quality of life (QoL) in patients with OI mainly depends on the severity of the skeletal deformities. However, it has become clear that additional factors can affect the QoL in all patients with OI. In this study, we compare dimensions of QoL in adults with OI with a control population. The SF-36 questionnaire was distributed among 330 adult patients with different OI types. Results were compared with two control populations from the Netherlands. Age-matched comparisons were made with one of the two control populations. The results were summarized in eight domains: general and mental health, physical and social function, bodily pain, vitality, and physical and emotional role. General health and physical function in all types of OI are low compared with controls, except patients with OI type 4 aged 55+ years. Bodily pain in patients with OI appeared significantly worse than in the control population. There was no significant difference between OI types regarding pain and vitality. Vitality was only in the OI type 1 group significantly lower compared with controls. Patients with OI type 1 had a significantly reduced mental health. Social functioning appeared most effective in type 3 around 20 years of age. QoL in adult patients with OI should be an important outcome measure in every OI clinic, but the amount of baseline data on this subject is sparse. This baseline measurement study is the largest study to date investigating QoL in adult patients with OI. The mean scores indicate that people with OI generally have a significantly lower QoL than the control population. Further qualitative evaluation of QoL and its influences is important for future management. © 2020 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

Interaction between KDELR2 and HSP47 as a Key Determinant in Osteogenesis Imperfecta Caused by Bi-allelic Variants in KDELR2.

Osteogenesis imperfecta (OI) is characterized primarily by susceptibility to fractures with or without bone deformation. OI is genetically heterogeneous: over 20 genetic causes are recognized. We identified bi-allelic pathogenic KDELR2 variants as a cause of OI in four families. KDELR2 encodes KDEL endoplasmic reticulum protein retention receptor 2, which recycles ER-resident proteins with a KDEL-like peptide from the cis-Golgi to the ER through COPI retrograde transport. Analysis of patient primary fibroblasts showed intracellular decrease of HSP47 and FKBP65 along with reduced procollagen type I in culture media. Electron microscopy identified an abnormal quality of secreted collagen fibrils with increased amount of HSP47 bound to monomeric and multimeric collagen molecules. Mapping the identified KDELR2 variants onto the crystal structure of G. gallus KDELR2 indicated that these lead to an inactive receptor resulting in impaired KDELR2-mediated Golgi-ER transport. Therefore, in KDELR2-deficient individuals, OI most likely occurs because of the inability of HSP47 to bind KDELR2 and dissociate from collagen type I. Instead, HSP47 remains bound to collagen molecules extracellularly, disrupting fiber formation. This highlights the importance of intracellular recycling of ER-resident molecular chaperones for collagen type I and bone metabolism and a crucial role of HSP47 in the KDELR2-associated pathogenic mechanism leading to OI.

Fatigue in adults with Osteogenesis Imperfecta.

BACKGROUND: Osteogenesis Imperfecta (OI) is characterized by bone fragility, and features such as blue sclerae, dentinogenesis imperfecta, hearing loss, ligamentous laxity and short stature can be present. It has long been assumed that the functional ability and quality of life of patients with OI depends primarily on the severity of skeletal deformities. However, fatigue is often mentioned in clinic by patients with all types of OI as an important modifier of their quality of life and does not always seem to be related to their functional ability. The aim of this study is to investigate whether adults with Osteogenesis Imperfecta are significantly more fatigued than the normal population. METHODS: The Fatigue Severity Scale (FSS) was distributed by mobile phone application among 151 adult patients with different OI types. Results of the FSS in the OI group were compared with two control populations from America (n = 20) and the Netherlands (n = 113). RESULTS: Ninety-nine patients (OI type 1 (n = 72), OI type 3 (n = 13), OI type 4 (n = 14) completed the FSS questionnaire. The mean FSS score of this cohort was 4.4 and significantly higher than the control populations (2.3/2.9). 65% of our cohort reported at least moderate fatigue compared with 2 control populations from America and the Netherlands. CONCLUSION: Fatigue in patients with OI is a frequently encountered problem in our expert clinic but research into this topic is sparse. This pilot study is the largest study to date investigating fatigue in patients with OI and results have been compared with two control groups. The mean FSS score of 4.4 in the OI group indicates that people with OI are generally significantly more fatigued than the control population. Further evaluation of fatigue and its influencers in a larger group of OI patients is important for future management.

The evolution of hand function during remodelling in nonreduced angulated paediatric forearm fractures: a prospective cohort study.

Forearm fractures are very common orthopaedic injuries in children. Most of these fractures are forgiving due to the unique and excellent remodelling capacity of the juvenile skeleton. However, significant evidence stating the limits of acceptable angulations and taking functional outcome into consideration is scarce. The aim of this study is, therefore, to get a first impression of the remodelling capacity in nonreduced paediatric forearm fractures based on radiological and functional outcome. Children aged 0-14 years with a traumatic angular deformation of the radius or both the radius and ulna, treated conservatively without reduction, were included in this prospective cohort study. Radiographs were taken and functional outcome was assessed at five fixed follow-up appointments throughout a period of one year. Outcome measurements comprised radiographic angular alignment, grip strength and wrist mobility. A total of 26 children (aged 3-13 years) with a traumatic angulation of the forearm were included. Mean dorsal angulation at the time of presentation amounted to 12° (5-18) and diminished after one year to a mean angulation of 4° (0-13). Grip strength, pronation and supination were significantly diminished compared to the unaffected hand up to 6 months after injury. After one year, no significant differences in function between the affected and the unaffected arm were found. Nonreduced angulated paediatric forearm fractures have the potential to remodel in time and have good radiographic and functional outcome one year after trauma, where pronation and grip strength take the longest to recover.

Bleeding and bruising in Osteogenesis Imperfecta: International Society on Thrombosis and Haemostasis bleeding assessment tool and haemostasis laboratory assessment in 22 individuals.

Osteogenesis imperfecta (OI) is characterized by susceptibility to bone fractures. Other symptoms, such as easy bruising and bleeding complications during surgery necessitating transfusions, have also been reported. The aim of the cross-sectional pilot study was to assess the bleeding and bruising tendency in OI patients and to screen for possible underlying haematological disorders. Bleeding tendency was investigated using the International Society on Thrombosis and Haemostasis bleeding assessment tool (ISTH-BAT) in 22 adult OI patients. Laboratory testing was performed to investigate for bleeding disorders or abnormal coagulation. Four patients [OI type 1(n = 3), OI type 4(n = 1)] had a bleeding score (BS) fitting with a bleeding tendency, but without test results pointing to a coagulopathy. Two patients [OI type 1(n = 1), OI type 3 (n = 1)] without a bleeding tendency according to the BS had increased fibrinolysis. This is the second largest study to date addressing bleeding tendency in OI and the first study to use ISTH-BAT and elaborate laboratory testing for coagulopathies. Four patients had an increased bleeding tendency. However, laboratory testing demonstrated no bleeding disorder or abnormal coagulation. Increased fibrinolysis was demonstrated in two patients without bleeding tendency on BS. Vascular fragility as a cause of bleeding tendency in OI has been suggested earlier. Further research on bleeding tendency in OI is important.

Adults with osteogenesis imperfecta: Clinical characteristics of 151 patients with a focus on bisphosphonate use and bone density measurements.

An expert center for adults with Osteogenesis Imperfecta (OI) has been founded at the Isala Hospital in Zwolle, the Netherlands to achieve optimal care for adults with OI. Clinical data such as patient history, Dual Energy X-ray Absorptiometry measurements and laboratory findings are collected with patient consent. This study provides an overview of clinical characteristics of the patients who visited the clinic during its first 5 years, a total of 151 patients. In this study, we focus on bisphosphonate use and bone density measurements at time of presentation at the expert center. As such, insight into the natural history of OI in adults will be increased. Analysing the data of a large group of adults with this rare disorder within a national expert center will allow detailed exploration of the course of OI over time.

10-m Shuttle Ride Test in Youth With Osteogenesis Imperfecta Who Use Wheelchairs: Feasibility, Reproducibility, and Physiological Responses.

BACKGROUND: Physical fitness levels in youth with osteogenesis imperfecta (OI) who use wheelchairs are unknown. The 10-m Shuttle Ride Test (SRiT) has recently been introduced as a field test to determine cardiorespiratory fitness in children with cerebral palsy who self-propel a wheelchair. OBJECTIVE: The purpose of this study was to investigate the feasibility and reproducibility of the SRiT, as well as the physiological responses to the SRiT, in youth with moderate-to-severe OI between 8 and 25 years of age who self-propel a wheelchair at least for long distances. DESIGN: A test-retest design was used. METHODS: Thirteen patients with OI (8 boys, 5 girls; mean±SD values for age=15.5±6.4 years) using a manual wheelchair performed 2 SRiTs within 2 weeks. Adverse events, reached stage, peak heart rate (HRpeak), peak respiratory exchange ratio (RERpeak), peak oxygen uptake (V̇o2peak), and peak minute ventilation (V̇epeak) were the main outcome parameters. RESULTS AND DISCUSSION: All participants performed a maximal effort at both SRiTs (mean±SD values for HRpeak of 195±9 beats per minute [bpm], RERpeak of 1.32±0.16, V̇o2peak of 25.4±5.6 mL·kg(-1)·min(-1), and V̇epeak of 47.9±18.6 L·min(-1)), without adverse events. The intraclass correlation coefficient of the reached stage showed excellent reliability (.95). Limits of agreement (LoA) analysis revealed acceptable LoA for reached stage (mean bias=-0.58, range=-2.50 to +1.35). There was a low correlation between reached stage and V̇o2peak (r=.61 and r=.45 for the first and second SRiTs, respectively). LIMITATIONS: The influence of wheelchair properties and individually adjusted wheelchair designs was not examined. CONCLUSIONS: The SRiT appears to be a feasible, safe, and reproducible maximal field test in youth with OI using wheelchairs at least for long distances. This field test might be useful to provide an indication of physical fitness and to assess the efficacy of interventions on physical fitness in these patients.

PLS3 mutations in X-linked osteoporosis with fractures.

Plastin 3 (PLS3), a protein involved in the formation of filamentous actin (F-actin) bundles, appears to be important in human bone health, on the basis of pathogenic variants in PLS3 in five families with X-linked osteoporosis and osteoporotic fractures that we report here. The bone-regulatory properties of PLS3 were supported by in vivo analyses in zebrafish. Furthermore, in an additional five families (described in less detail) referred for diagnosis or ruling out of osteogenesis imperfecta type I, a rare variant (rs140121121) in PLS3 was found. This variant was also associated with a risk of fracture among elderly heterozygous women that was two times as high as that among noncarriers, which indicates that genetic variation in PLS3 is a novel etiologic factor involved in common, multi-factorial osteoporosis.