Anti-RANKL Therapy Prevents Glucocorticoid-Induced Bone Loss and Promotes Muscle Function in a Mouse Model of Duchenne Muscular Dystrophy.

Bisphosphonates prevent bone loss in glucocorticoid (GC)-treated boys with Duchenne muscular dystrophy (DMD) and are recommended as standard of care. Targeting receptor activator of nuclear factor kappa-B ligand (RANKL) may have advantages in DMD by ameliorating dystrophic skeletal muscle function in addition to their bone anti-resorptive properties. However, the potential effects of anti-RANKL treatment upon discontinuation in GC-induced animal models of DMD are unknown and need further investigation prior to exploration in the clinical research setting. In the first study, the effects of anti-RANKL and deflazacort (DFZ) on dystrophic skeletal muscle function and bone microstructure were assessed in mdx mice treated with DFZ or anti-RANKL, or both for 8 weeks. Anti-RANKL and DFZ improved grip force performance of mdx mice but an additive effect was not noted. However, anti-RANKL but not DFZ improved ex vivo contractile properties of dystrophic muscles. This functional improvement was associated with a reduction in muscle damage and fibrosis, and inflammatory cell number. Anti-RANKL treatment, with or without DFZ, also improved trabecular bone structure of mdx mice. In a second study, intravenous zoledronate (Zol) administration (1 or 2 doses) following 2 months of discontinuation of anti-RANKL treatment was mostly required to record an improvement in bone microarchitecture and biomechanical properties in DFZ-treated mdx mice. In conclusion, the ability of anti-RANKL therapy to restore muscle function has profound implications for DMD patients as it offers the possibility of improving skeletal muscle function without the steroid-related skeletal side effects.

Skeletal disproportion in girls with Turner syndrome and longitudinal change with growth-promoting therapy.

OBJECTIVE: Short stature in Turner syndrome (TS) may be accompanied by skeletal disproportion. This retrospective study investigates growth and disproportion from early childhood to adult height. STUDY DESIGN: Data were collected from 59 girls prior to growth hormone (rhGH) treatment and in 30 girls followed up longitudinally. Standard deviation scores (SDS) for height (Ht), sitting height (SH) and sub-ischial leg length (LL) were compared and a disproportion score (SH SDS - LL SDS) calculated. RESULTS: In 59 girls, mean (SD) age 6.6 (2.1) years prior to rhGH treatment, LL SDS of -3.4 (1.1) was significantly lower than SH SDS of -1.2 (0.8) [p < .001]. In girls with Ht SDS < -2.0, disproportion score was > +2.0 in 27 (63%), cf eight (50%) with Ht SDS ≥ -2.0. For the longitudinal analysis, skeletal disproportion prior to rhGH was +2.4 (1.1) and +1.7 (1.0) on rhGH but prior to introduction of oestrogen [p < .001]. Disproportion at adult height was +1.1 (0.8), which was less marked than at the earlier time points [p < .001 for both comparisons]. Change in disproportion SDS over the first two years of rhGH predicted overall change in disproportion from baseline to adult height [R2 51.7%, p < .001]. CONCLUSION: TS is associated with skeletal disproportion, which is more severe in the shortest girls and present in only half of those with milder degrees of short stature. Growth-promoting therapy may improve disproportion during both the childhood and pubertal phases of growth. Change in disproportion status two years after starting rhGH helps predict disproportion at adult height.

Observer Agreement of Vertebral Fracture Grading Using Dual Energy Absorptiometry Vertebral Fracture Assessment in Duchenne Muscular Dystrophy.

Routine screening of the spine for vertebral fracture is recommended in the recent international standards of care for boys with Duchenne muscular dystrophy (DMD). Recent international consensus endorses the use of dual energy absorptiometry vertebral fracture assessment for identification of vertebral fractures in children, which could be used instead of spine radiographs. This study aims to evaluate the inter-observer agreement for vertebral fracture classification in boys with DMD, and the impact on clinical management. Dual energy absorptiometry vertebral fracture assessment and morphometric analysis in 39 boys was performed by a reader with no prior experience (R1) and 2 readers with experience (R2 and R3). Inter-observer concordance of vertebral fracture grading comparing R1 with R2 and R3 was substantial (Kappa 0.66, 95% CI 0.56, 0.76). Concordance between R2 and R3 was almost perfect (Kappa 0.93, 95% CI 0.89, 0.97) which did not lead to differences in clinical management. Grading by R1 in comparison to R2 and R3 would have led to change in management of 5/39 boys (13%), according to recent standards of care guidance. Structured education programme on identification of vertebral fractures should be explored to ensure consistency of reporting of this important health outcome measure in DMD.

Skeletal disproportion in glucocorticoid-treated boys with Duchenne muscular dystrophy.

We aimed to compare body segment and bone lengths in glucocorticoid-treated boys with Duchenne muscular dystrophy (DMD) with healthy controls using dual-energy absorptiometry (DXA) images. Total height (Ht), sitting height (SH), leg length (LL) and bone lengths (femur, tibia) in boys with DMD and age-matched control boys were measured using DXA. Thirty boys with DMD (median age 10.0 years (6.1, 16.8)) were compared with 30 controls. SH in DMD was 3.3 cm lower (95% CI - 6.1, - 0.66; p = 0.016). LL in DMD was 7.3 cm lower (95% CI - 11.2, - 3.4; p < 0.0001). SH:LL of boys with DMD was higher by 0.08 (95% CI 0.04, 0.12; p < 0.0001). Femur length in DMD was 2.4 cm lower (95% CI - 4.6, - 0.12; p = 0.04), whereas tibial length in DMD was 4.8 cm lower (95% CI - 6.7, - 2.9; p < 0.0001). SH:LL was not associated with duration of glucocorticoid use (SH:LL ß = 0.003, 95% CI - 0.01 to 0.002, p = 0.72).Conclusion: Glucocorticoid-treated boys with DMD exhibit skeletal disproportion with relatively shorter leg length and more marked reduction of distal long bones. As glucocorticoid excess is not associated with such disproportion, our findings raise the possibility of an intrinsic disorder of growth in DMD. What is Known • Severe growth impairment and short stature are commonly observed in boys with Duchenne muscular dystrophy (DMD), especially those treated with long-term glucocorticoids (GC). • In other groups of children with chronic conditions and/or disorders of puberty, skeletal disproportion with lower spinal length has been reported. What is New • Growth impairment in GC-treated boys with DMD was associated with skeletal disproportion in relation to age, with lower limbs and distal long bones affected to a greater degree.

Persistence of Muscle-bone Deficits Following Anti-tumour Necrosis Factor Therapy in Adolescents With Crohn Disease.

OBJECTIVES: The aim of the study is to assess change in the muscle-bone unit in adolescents with Crohn disease (CD) on anti-tumour necrosis factor (anti-TNFα). METHODS: Prospective study following anti-TNFα in 19 adolescents with CD with a median age (range) of 15.1 years (11.2, 17.2). At baseline, 6 and 12 months, subjects had a biochemical assessment of insulin growth factor axis, bone turnover and muscle-bone health by dual energy absorptiometry (DXA), peripheral quantitative computed tomography (pQCT), and dynamic isometry. RESULTS: Significant clinical improvement in disease activity was observed by 2 weeks (P = 0.004 vs baseline) and maintained at 12 months (P = 0.038 vs baseline). Median bone specific alkaline phosphatase standard deviation score (SDS) increased from -1.7 (-3.6 to -1.0) to -1.2 (-3.6 to -0.5) by 6 weeks (P = 0.01). At baseline, DXA total body and lumbar spine bone mineral density (BMD) SDS was -0.9 (-2.3 to 0.5) and -1.1 (-2.9 to 0.4), respectively. At baseline, pQCT trabecular BMD SDS at 4% tibia and muscle cross-sectional area SDS at 66% radius was -1.6 (-3.2 to 1.1) and -2.4 (-4.3 to -0.3), respectively. At baseline, maximal isometric grip force (MIGF) of the non-dominant hand adjusted for height was -1.5 (-4.5 to 0.49). All these deficits in muscle-bone persisted at 6 and 12 months. CONCLUSIONS: Despite improvement in disease and osteoblast activity, bone and muscle deficits, as assessed by DXA, pQCT, and grip strength in adolescents with CD did not improve following twelve months of anti-TNFα.

Long-term health outcomes of adults with McCune-Albright syndrome.

CONTEXT: McCune-Albright syndrome (MAS) is associated with numerous health problems. Comprehensive long-term health problems of adults with MAS are less well defined in the literature. OBJECTIVE: Our objective is to report comprehensive health outcomes of adults with MAS (>18 years). DESIGN: Retrospective case note review of 16 adults with MAS managed by one clinician. Results expressed as median (range). RESULTS: The study included 16 adults (seven males) with MAS. Median current age is 29 years (20, 46). Twelve of 16 had craniofacial fibrous dysplasia with five of 12 (42%) with progressive facial asymmetry. Growth hormone excess was observed in six of 16 (38%) and T3-toxicosis in five of 16 (31.3%). Six of the seven men (86%) had abnormalities on testicular ultrasound with one man exhibiting marked atrophy of germ and sertoli cells with reduction in spermatogenesis. Six of the 16 (38%) had cardiorespiratory complications including high output cardiac failure (n,3), hypertension (n,2) and one man with congestive cardiac failure and restrictive lung disease. Six of eight (66%) who had screening endoscopy for upper gastrointestinal polyps show increasing numbers of polyps, with benign histology to date. One woman with a previous history of early puberty presented with early aggressive breast carcinoma, which was positive for GNAS. Two patients had GNAS-positive muscle myomas. Platelet dysfunction with bleeding tendency responsive to platelet transfusion during surgery was seen in four. CONCLUSION: A range of complex health problems is encountered in adults with MAS. These have important implications for transition of patients with MAS and adult care. Long-term cancer risk is currently unknown but requires careful follow-up.

Turner syndrome--issues to consider for transition to adulthood.

BACKGROUND: Turner syndrome (TS) is associated with a spectrum of health problems across the age span, which requires particular attention during the transition period in these adolescents. AREAS OF AGREEMENT: The majority of girls with TS require oestrogen replacement from puberty onwards, which is important for adequate feminization, uterine development and maintenance of bone health. There is a lifetime increased risk from autoimmune conditions like hypothyroidism, coeliac disease, hearing loss and aortic dilatation with the potential to lead to aortic dissection. A systematic and holistic approach to provision of health care in TS is needed. AREAS OF CONTROVERSY: Several unanswered questions remain, including the choice of hormone replacement therapy in the young person with TS and in adulthood; the optimal mode of cardiovascular assessment; the best management and assessment prior to and during pregnancy. AREAS TIMELY FOR DEVELOPING RESEARCH: The optimal model of care and transition to adult services in TS requires attention. Further research is needed in relation to cardiovascular risk assessment, pregnancy management and hormone replacement therapy in TS.

The prevalence of turner syndrome in girls presenting with coarctation of the aorta.

OBJECTIVE: To determine the prevalence of Turner syndrome in girls presenting with coarctation of the aorta (CoA). STUDY DESIGN: A total of 132 girls with known structural CoA was identified. Those girls who had no previous karyotype analysis performed were asked to participate in a research study in which a banded karyotype with 50-cell count was performed. RESULTS: Of 132 girls with CoA, 55 (41.7%) had karyotype analysis within 6 months of cardiac diagnosis. Three girls underwent karyotyping later because of clinical concerns. Of the 74 girls with CoA who had not had a karyotype, 38 (51.4%) consented to the study. Results were available for 37 girls. All were 46,XX. Five patients with Turner syndrome were identified in the 95 girls with CoA who had karyotype analysis (4 from early karyotype and 1 diagnosed later), which translated into a minimum prevalence of 5.3% of Turner syndrome in this group of girls with CoA. In addition, one infant with a 20-cell 46,XX karyotype had features of Turner syndrome. CONCLUSION: Our study demonstrated for the first time in a large cohort that 5.3% of girls presenting with CoA are found to have Turner syndrome when karyotyping is performed. Given the spectrum of preventable and treatable health problems after the diagnosis of Turner syndrome, we believe that all girls with CoA should have a karyotype analysis, ideally with at least 50-cell count, at the time of diagnosis of CoA.

Pathological fractures in paediatric patients with inflammatory bowel disease.

UNLABELLED: Paediatric inflammatory bowel disease (IBD), especially Crohn's disease (CD), is commonly associated with poor skeletal health, related to the direct effects of chronic inflammation, prolonged use of glucocorticoid (GC), poor nutrition, delayed puberty and low muscle mass. Low bone mineral density is commonly reported, although the prevalence of long bone fractures may not be increased in these patients. Emerging evidence however suggests that there may be an increased risk of vertebral fractures (VFs) in this group. VFs presenting at diagnosis of paediatric CD, prior to any GC exposure, have been reported, highlighting the deleterious effect of inflammation on skeletal health. This paper reviews the published literature on pathophysiology of skeletal morbidity and fractures in paediatric IBD, illustrated with a new case report of multiple VFs in a prepubertal girl with CD, soon after diagnosis, who received minimal amounts of oral GC. Optimising control of disease, addressing vitamin D deficiency, encouraging physical activity and ensuring normal growth and pubertal progression are paramount to management of bone health in these patients. Despite the lack of evidence, there may be a place for bisphosphonate treatment, especially in the presence of symptomatic pathological fractures, but this requires close monitoring by clinicians with expertise in paediatric bone health. CONCLUSION: Chronic inflammation mediated by pro-inflammatory cytokines may have adverse effects on skeletal health in paediatric patients with IBD. The risk of vertebral fractures may be increased, even without exposure to glucocorticoid. Clinical monitoring of these patients requires careful attention to the various factors that impact on bone health.

Aortic dilatation and dissection in Turner syndrome: what we know, what we are unclear about and what we should do in clinical practice?

Aortic dilatation and aortic dissection are increasingly recognised in patients with Turner syndrome (TS). Risk factors for aortic dissection include aortic dilatation, bicuspid aortic valves, coarctation of aorta and pregnancy. The risk of death due to aortic dissection in pregnancy in TS is 2%, which is approximately 100 times higher than the general population, as maternal mortality is extremely low. Ongoing cardiovascular monitoring is recommended, although there remain several unanswered questions in relation to cardiovascular imaging especially the choice of modality for detection of vascular, valvular abnormalities and measurements of aortic dimensions. Due to the relative short stature of patients with TS, aortic dimensions need to be defined by aortic measurements adjusted for body surface area, known as aortic sized index (ASI). The relationship of ASI and other risk factors with aortic dissection is only beginning to be clarified. Clinical management and monitoring of such patients should be delivered by a group of clinicians familiar with the issues unique to TS patients in a multidisciplinary fashion. All clinicians including the non-specialists need to have a low threshold of suspecting aortic dissection in these adolescents and young adults. This up to date review, including a summary of all 122 published cases of TS patients with aortic dissection, aims to provide a summary of recent publications on characteristics of aortic dissection and aortic dilatation in TS to highlight gaps in knowledge and propose possible clinical monitoring pathway of cardiovascular health in children and adults with TS. Cardiovascular assessment and risk counselling is especially crucial during the period of transition of adolescents with TS, although life long monitoring by expert cognizant to the issues specific in TS is essential.

Frequency of Delayed Puberty in Boys with Contemporary Management of Duchenne Muscular Dystrophy.

Background: Delayed puberty is thought to be common in boys with Duchenne muscular dystrophy (DMD) treated with long term oral glucocorticoid. This study aims to report the frequency of delayed puberty in DMD from examination by a paediatric endocrinologist alongside detailed endocrine investigations. Methods: All boys with DMD aged at least 14 years in January 2022 known to the paediatric neuromuscular service (2016-2022) were included in this study. Delayed puberty was defined based on testicular volume and genital staging in comparison to published puberty nomogram. Results: Twenty-four out of 37 boys (65%) had evidence of delayed puberty, 23/24 (96%) of those with delayed puberty were on glucocorticoid therapy all of whom were on daily glucocorticoid. On the other hand, 7/13 (54%) of those with normal timing of puberty were on glucocorticoid; 2/7 (29%) were on the intermittent regimen. Of those who were on daily glucocorticoid therapy at the time of assessment of puberty, 23/28 (82%) had evidence of delayed puberty. In boys with delayed puberty, endocrine investigations showed low luteinizing hormone (LH) with undetectable testosterone levels, a pre-pubertal response with lutenizing hormone releasing hormone test and sub-optimal testosterone levels with prolonged human chorionic gonadotropin stimulation. Conclusion: The frequency of delayed puberty in boys with DMD was 65%. Eighty-two percent of adolescent boys with DMD on daily glucocorticoid had evidence of delayed puberty. Biochemical investigations point to functional central hypogonadism in these adolescents. Our data supports the routine monitoring of puberty in boys with DMD.

Severity of acute phase reaction in children receiving the first dose of zoledronic acid and the impact of the underlying condition: a cross-sectional study.

INTRODUCTION: Zoledronic acid (ZA), used for treatment of children with osteoporosis, can cause acute phase reaction (APR) following the first infusion. Many institutions have a policy to admit and monitor all children for their first ZA infusion. OBJECTIVE: To determine if the APR with the first ZA dose warrants hospital-level care and evaluate if its severity correlates with the underlying condition. DESIGN: Retrospective cross-sectional analysis. SETTINGS: Two tertiary centres across the UK that run paediatric metabolic bone disease services. PATIENTS: Children who received first ZA infusion as inpatients at these centres. INTERVENTIONS: Nil. MAIN OUTCOME MEASURES: The Paediatric Early Warning Score (PEWS) and length of hospital stay to assess the severity of APR. RESULTS: 107 patients were included. Peak PEWS≤3 was found in 85% of children. 83% required admission for <24 hours. The various patient populations (osteogenesis imperfecta (OI), immobility-induced osteoporosis, idiopathic juvenile osteoporosis, systemic inflammatory disorders and steroid-induced osteoporosis, Duchenne muscular dystrophy (DMD)) did not differ significantly in the mean peak PEWS and the length of hospital stay. However, when compared directly, the group with DMD and that with systemic inflammatory disorders and steroid-induced osteoporosis differed significantly in the mean peak PEWS (p=0.011) and the length of hospital stay (p=0.048), respectively, as compared with the OI group. CONCLUSION: Most patients had a mild APR not requiring overnight hospital admission, after their first ZA dose. However, certain groups seem to suffer more severe APR and may warrant consideration of inpatient monitoring with the first infusion.

Rapidly evolving hypopituitarism in a boy with multiple autoimmune disorders.

A 10-year-old boy with acute onset cranial diabetes insipidus and multiple autoimmune disorders had evolving panhypopituitarism, thought to be due to autoimmune hypophysitis. Over 18 months, a dramatic clinical course with progressive hypopituitarism and development of type 1 diabetes mellitus was evident. Serial brain imaging showed changes suggestive of germinoma.

The prevalence of hypertension in paediatric Turner syndrome: a systematic review and meta-analysis.

Cardiovascular related deaths account for over 40% of the excess mortality in Turner syndrome (TS). Hypertension, a modifiable risk factor for both aortic dilatation and dissection, is more commonly encountered in TS during childhood and adolescence. Treatment of hypertension is currently recommended beyond the age of 16 years in TS to help reduce the risk of aortic dissection. This study aims to determine the prevalence of hypertension in paediatric patients with TS and explore the associated methodologies of blood pressure evaluation reported in these studies. Three online databases were searched (Medline, Embase and Web of Science) for literature which reported a prevalence, or allowed calculation of prevalence, of hypertension in patients with TS who were 18 years of age or younger. Seventeen studies which met the primary eligibility criteria, with a total of 1948 patients, were included. The estimated pooled prevalence of hypertension in children and adolescents with TS was 16% (95% CI: 8.9-24.6%). There was significant heterogeneity detected between the studies. The prevalence of hypertension in those studies which assessed 24-h Ambulatory Blood Pressure Monitoring (ABPM) was 21.1% (95% CI: 15.2-27.6%) compared those which used another method of blood pressure measurement which was 13.5% (95% CI: 5.2-24.4%). Given the impact of hypertension with long-term health outcomes and the reversibility of these same outcomes by addressing abnormal blood pressure, prompt and early diagnosis of hypertension in young girls with TS should be prioritised. We recommend the use of 24-h ABPM in screening for hypertension in the paediatric TS population.

The Physiology and Mechanisms of Growth.

na.

Emergency and perioperative management of adrenal insufficiency in children and young people: British Society for Paediatric Endocrinology and Diabetes consensus guidance.

Adrenal insufficiency (AI) is characterised by lack of cortisol production from the adrenal glands. This can be a primary adrenal disorder or secondary to adrenocorticotropic hormone deficiency or suppression from exogenous glucocorticoids. Symptoms of AI in children may initially be non-specific and include growth faltering, lethargy, poor feeding, weight loss, abdominal pain, vomiting and lingering illnesses. AI is treated with replacement doses of hydrocortisone. At times of physiological stress such as illness, trauma or surgery, there is an increased requirement for exogenous glucocorticoids, which if untreated can lead to an adrenal crisis and death. There are no unified guidelines for those <18 years old in the UK, leading to substantial variation in the management of AI. This paper sets out guidance for intercurrent illness, medical, dental and surgical procedures to allow timely and appropriate recognition and treatment of AI and adrenal crisis for children and young people.

Objective and subjective measures of sleep in men with Muscular Dystrophy.

PURPOSE: Despite poor sleep quality being recognised in Duchenne Muscular Dystrophy, reports from milder forms of Muscular Dystrophy (MD), and accompanied associations with quality of life (QoL), pain and fatigue, remain limited however. METHODS: Adult males (n = 15 Beckers MD (BMD), n = 12 Limb-Girdle MD (LGMD), n = 12 Fascioscapulohumeral (FSHD), n = 14 non-MD (CTRL)) completed assessments of body composition (Bio-electrical impedance), sleep (7-day 24-hour tri-axial accelerometer, Pittsburgh Sleep Quality Index (PSQI) and Insomnia Severity Index, QoL (SF36-v2), pain (Visual analogue scale), fatigue (Modified Fatigue Index Scale) and functional assessments (Brookes and Vignos). RESULTS: FSHD and BMD reported worse sleep than CTRL on the PSQI. FSHD scored worse than CTRL on the Insomnia Severity Index (P<0.05). 25-63% and 50-81% of adults with MD reported poor sleep quality using the Insomnia Severity Index and PSQI, respectively. Accelerometery identified no difference in sleep quality between groups. Associations were identified between sleep measures (PSQI global and insomnia severity) with mental or physical QoL in LGMD, BMD and FSHD. Multiple regression identified associations between sleep impairment and fatigue severity (all MDs), body composition (BMD & LGMD), upper and lower limb function (LGMD, FSHD) and age (FSHD). CONCLUSIONS: 25-81% of men with MD, depending on classification, experience sleep impairment, using self-report sleep measures. Whilst BMD and FSHD showed worse sleep outcomes than CTRL, no group difference was observed between LGMD and CTRL, however all groups showed associations with sleep impairment and higher levels of fatigue. These findings, and associations with measures of health and wellbeing, highlight an area for further research which could impact QoL in adults with MD.

The effect of COVID-19 on the presentation of thyroid disease in children.

Introduction: Although studies suggest a potential link between COVID-19 and thyroid dysfunction in adults, there are insufficient data to confirm that association in children, and whether there is any effect on presentation to healthcare services. Aims: To identify whether presentations of thyroid dysfunction in children to a tertiary paediatric hospital changed as a result of the COVID-19 pandemic. Methods: A retrospective case note review was conducted of all children with abnormal thyroid function tests between 1st January 2016 and 31st December 2021 at a tertiary paediatric endocrine centre in the United Kingdom. Results: Overall, 244 children whose first presentation was within the timeframe of interest were included in this study, with a median age (range) of 11.5 (6.1, 16.8) years. Of these, 43 (18%) were hyperthyroid and 201 (82%) were hypothyroid. The greatest number of thyroid presentations occurred in 2021 (n=60, 25% of total over time period) and the fewest in 2020 (n=10, 4% of total over time period). Prior to this, the median (range) number of presentations per year was 34 (28, 39). There were no statistically significant differences in biochemistry, antibody status or other clinical characteristics between those who presented with hyperthyroidism prior to the pandemic or after. In those with hypothyroidism, baseline biochemistry was similar between the 2 groups, but the presence of other autoimmune conditions was greater pre-pandemic (17.2% vs 15.0%, p=0.03). In addition, patients were more likely to have transient thyroid dysfunction, which did not require treatment post-pandemic (70.0% vs 49.6%, p=0.0086). Conclusions: Although overall rates of presentation with thyroid dysfunction have not altered since the first wave of the COVID-19 pandemic, presentations with transient thyroid dysfunction, not requiring ongoing treatment have increased. Further research regarding the relationship between COVID-19 and thyroid function in children and young people, is needed.

3T-MRI-based age, sex and site-specific markers of musculoskeletal health in healthy children and young adults.

Objective: The aim of this study is to investigate the role of 3T-MRI in assessing musculoskeletal health in children and young people. Design: Bone, muscle and bone marrow imaging was performed in 161 healthy participants with a median age of 15.0 years (range, 8.0, 30.0). Methods: Detailed assessment of bone microarchitecture (constructive interference in the steady state (CISS) sequence, voxel size 0.2 × 0.2 × 0.4 mm3), bone geometry (T1-weighted turbo spin echo (TSE) sequence, voxel size 0.4 × 0.4 × 2 mm3) and bone marrow (1H-MRS, point resolved spectroscopy sequence (PRESS) (single voxel size 20 × 20 × 20 mm3) size and muscle adiposity (Dixon, voxel size 1.1 × 1.1 × 2 mm3). Results: There was an inverse association of apparent bone volume/total volume (appBV/TV) with age (r = -0.5, P < 0.0005). Cortical area, endosteal and periosteal circumferences and muscle cross-sectional area showed a positive association to age (r > 0.49, P < 0.0001). In those over 17 years of age, these parameters were also higher in males than females (P < 0.05). This sex difference was also evident for appBV/TV and bone marrow adiposity (BMA) in the older participants (P < 0.05). AppBV/TV showed a negative correlation with BMA (r = -0.22, P = 0.01) which also showed an association with muscle adiposity (r = 0.24, P = 0.04). Cortical geometric parameters were highly correlated with muscle area (r > 0.57, P < 0.01). Conclusions: In addition to providing deep insight into the normal relationships between bone, fat and muscle in young people, these novel data emphasize the role of MRI as a non-invasive method for performing a comprehensive and integrated assessment of musculoskeletal health in the growing skeleton.

Multivariate analyses of factors that affect neonatal screening thyroid stimulating hormone.

AIMS: All screening programmes in the UK use a primary thyroid stimulating hormone (TSH) screen for congenital hypothyroidism. Recent attention has been paid to aspects of screening, such as the relation between blood spot TSH levels and birth weight or gestational age. The aim of our study was to determine the factors affecting screening neonatal TSH levels. METHODS: We conducted a retrospective analysis of blood spot screening TSH levels of all infants screened at a single regional screening laboratory. RESULTS: There were 6498 infants screened during a 12-week period. Screening TSH level showed negative correlation with gestational age and birth weight. Multiple linear regression analysis revealed low birth weight as the only independent factor affecting screening TSH level. CONCLUSIONS: Low birth weight infants appear to be at risk of thyroidal dysfunction. Our study showed that there were clinically significant but weak correlation between higher screening TSH levels and low birth weight. The clinical importance of these findings requires larger prospective studies to further elucidate the relevance of these factors affecting TSH screening levels.