Determinants of Low Bone Turnover in Type 2 Diabetes-the Role of PTH.

Determinants of low bone turnover in type 2 diabetes (T2DM) are poorly understood. To investigate the relationship between markers of bone turnover, glycaemic control, disease duration and calciotropic hormones in T2DM we assessed baseline biochemical data from the DiabOS Study, a prospective multicenter observational cohort study. In a cross-sectional study-design data from 110 postmenopausal women and men aged 50-75 years diagnosed with T2DM for at least 3 years and 92 non-diabetic controls were evaluated. Biochemical markers of bone formation (N-terminal propeptide of type I procollagen [PINP]), bone-specific alkaline phosphatase [BAP]) and resorption (C-terminal cross-linking telopeptide of type I collagen [CTX]), measures of calcium homeostasis (intact parathormone [iPTH], 25-Hydroxyvitamin D, calcium, magnesium) and glycaemic control were assessed. After adjustment for age, gender and body mass index (BMI), patients with T2DM had lower serum levels of PINP (p < 0.001), CTX (p < 0.001), iPTH (p = 0.03) and magnesium (p < 0.001) compared to controls. Serum calcium, creatinine, 25-Hydroxyvitamin D and sclerostin did not differ between both groups. In multivariate linear regression analyses only serum iPTH remained an independent determinant of bone turnover markers in T2DM (PINP: p = 0.02; CTX: p < 0.001 and BAP: p < 0.01), whereas glycated haemoglobin (HbA1c), disease duration, age and BMI were not associated with bone turnover. In conclusion low bone turnover in T2DM is associated with low iPTH. The underlying mechanism remains to be elucidated.

Fibroblast growth factor 21 predicts outcome in community-acquired pneumonia: secondary analysis of two randomised controlled trials.

Acute systemic inflammatory conditions are accompanied by profound alterations of metabolism. However, the role of fibroblast growth factor 21 (FGF21), a recently identified central regulator of metabolism, is largely unknown in community-acquired pneumonia (CAP). This study aims to characterise the pattern of FGF21 in pneumonia and associations with disease severity and outcome.This is a secondary analysis of two independent multicentre randomised controlled trials in patients presenting to the emergency department with CAP. Primary and secondary efficacy parameters included 30-day mortality, length of hospital stay, time to clinical stability and duration of antibiotic treatment.A total of 509 patients were included in the analysis. FGF21 levels at admission strongly correlated with disease severity, as measured by the Pneumonia Severity Index. Increased levels of FGF21 were associated with prolonged time to clinical stability, antibiotic treatment and hospitalisation. FGF21 levels at admission were significantly higher in nonsurvivors than in survivors, yielding a 1.61-fold increased adjusted odds ratio of 30-day mortality (95% CI 1.21-2.14; p=0.001). Moreover, FGF21 was found to identify patients for 30-day mortality with superior discriminative power compared with routine diagnostic markers.Moderate-to-severe CAP patients with higher levels of FGF21 were at increased risk for clinical instability, prolonged hospitalisation and 30-day all-cause mortality.

Metabolomics and Their Ability to Distinguish Thyroid Disorders: A Retrospective Pilot Study.

Early diagnosis of thyroid disorders is key to further treatment. We assessed the ability of a high-throughput proton NMR metabolomic profile to distinguish disease type amongst of Graves' disease (n=87), Hashimoto's thyroiditis (n=17), toxic goiter (n=11), and autoimmune thyroiditis [i. e., subacute thyroiditis (n=4), postpartum thyroiditis (n=1)]. This observational study was conducted investigating patients presenting with a thyroid disorder at a Swiss hospital endocrine referral center and an associated endocrine outpatient clinic. The main outcome was diagnosis of thyroid disorder based on classical parameters. Blood draws took place as close as possible to treatment initiation. We performed one-way ANOVA and partial least squares discriminant analysis (PLS-DA) as multivariate classification and feature ranking method. One-way ANOVA analysis yielded following significantly different metabolites, triglycerides in small VLDL, triglycerides in very small VLDL, and triglycerides in large LDL (FDR=0.04). There was no distinct separation of any of the 4 diagnoses by PLS-DA. We did not find a metabolomic biomarker combination capable of predicting diagnosis. Preanalytical issues might have influenced our results. We strongly suggest replicating our work in another cohort.

Comparison of Five TSH-Receptor Antibody Assays in Graves' disease: results from an observational pilot study.

BACKGROUND: Early diagnosis and relapse prediction in Graves' disease influences treatment. We assessed the abilities of four TSH-receptor antibody tests [TRAb] and one cyclic adenosine monophosphate bioassay to predict relapse of Graves' disease. METHODS: Observational study investigating patients presenting with Graves' disease at a Swiss hospital endocrine referral center or an endocrine outpatient clinic. Main outcomes were diagnosis and relapse of Graves' disease after stop of anti-thyroid drugs. We used Cox regression to study associations of TRAb levels with relapse risk and calculated c-statistics [AUC] to assess discrimination. Blood draws took place as close as possible to treatment initiation. RESULTS: AUCs ranged from 0.90 (TSAb Biossay by RSR) to 0.97 (IMMULITE TSI by Siemens). Highest sensitivity (94.0%) was observed for IMMULITE TSI and RSR TRAb Fast, while the greatest specificity (97.9%) was found with the EliA anti-TSH-R (by Thermo Fisher). In Cox regression analysis comparing the highest versus the lower quartiles, the highest hazard ratio [HR] for relapse was found for BRAHMS TRAK (by Thermo Fisher) (2.98, 95% CI 1.13-7.84), IMMULITE TSI (2.40, 95% CI 0.91-6.35), EliA anti-TSH-R (2.05, 95% CI 0.82-5.10), RSR Fast TRAb (1.80, 95% CI 0.73-4.43), followed by RSR STIMULATION (1.18, 95% CI 0.46-2.99). Discrimination analyses showed respective AUCs of 0.68, 0.65, 0.64, 0.64, and 0.59. CONCLUSION: The assays tested had good diagnostic power and relapse risk prediction with few differences among the new assays. Due to the small sample size and retrospective design with possible selection bias, our data need prospective validation.

A cohort of 17 patients with kyphoscoliotic Ehlers-Danlos syndrome caused by biallelic mutations in FKBP14: expansion of the clinical and mutational spectrum and description of the natural history.

PurposeIn 2012 we reported in six individuals a clinical condition almost indistinguishable from PLOD1-kyphoscoliotic Ehlers-Danlos syndrome (PLOD1-kEDS), caused by biallelic mutations in FKBP14, and characterized by progressive kyphoscoliosis, myopathy, and hearing loss in addition to connective tissue abnormalities such as joint hypermobility and hyperelastic skin. FKBP14 is an ER-resident protein belonging to the family of FK506-binding peptidyl-prolyl cis-trans isomerases (PPIases); it catalyzes the folding of type III collagen and interacts with type III, type VI, and type X collagens. Only nine affected individuals have been reported to date.MethodsWe report on a cohort of 17 individuals with FKBP14-kEDS and the follow-up of three previously reported patients, and provide an extensive overview of the disorder and its natural history based on clinical, biochemical, and molecular genetics data.ResultsBased on the frequency of the clinical features of 23 patients from the present and previous cohorts, we define major and minor features of FKBP14-kEDS. We show that myopathy is confirmed by histology and muscle imaging only in some patients, and that hearing impairment is predominantly sensorineural and may not be present in all individuals.ConclusionOur data further support the extensive clinical overlap with PLOD1-kEDS and show that vascular complications are rare manifestations of FKBP14-kEDS.

Bone mineral density and its determinants in men with opioid dependence.

Data on the influence of opioid substitution therapy (OST) on skeletal health in men is limited. This cross-sectional study aimed to determine the prevalence of low bone mass in male drug users and to evaluate the relationship between endogenous testosterone and bone mass. We recruited 144 men on long-term opioid maintenance therapy followed in the Center of Addiction Medicine in Basel, Switzerland. Data on medical and drug history, fracture risk and history of falls were collected. Bone mineral density (BMD) was evaluated by densitometry and serum was collected for measurements of gonadal hormones and bone markers. 35 healthy age- and BMI-matched men served as the control group. The study participants received OST with methadone (69 %), morphine (25 %) or buprenorphine (6 %). Overall, 74.3 % of men had low bone mass, with comparable bone mass irrespective of OST type. In older men (≥40 years, n = 106), 29.2 % of individuals were osteoporotic (mean T-score -3.0 ± 0.4 SD) and 48.1 % were diagnosed with osteopenia (mean T-score -1.7 ± 0.4 SD). In younger men (n = 38), 65.8 % of men had low bone mass. In all age groups, BMD was significantly lower than in age-and BMI-matched controls. In multivariate analyses, serum free testosterone (fT) was significantly associated with low BMD at the lumbar spine (p = 0.02), but not at the hip. When analysed by quartiles of fT, lumbar spine BMD decreased progressively with decreasing testosterone levels. We conclude that low bone mass is highly prevalent in middle-aged men on long-term opioid dependency, a finding which may partly be determined by partial androgen deficiency.

Effects of Incretin-Based Therapies and SGLT2 Inhibitors on Skeletal Health.

Anti-diabetic drugs are widely used and are essential for adequate glycemic control in patients with type 2 diabetes. Recently, marketed anti-diabetic drugs include incretin-based therapies (GLP-1 receptor agonists and DPP-4 inhibitors) and sodium-glucose co-transporter 2 (SGLT2) inhibitors. In contrast to well-known detrimental effects of thiazolidinediones on bone metabolism and fracture risk, clinical data on the safety of incretin-based therapies is limited. Based on meta-analyses of trials investigating the glycemic-lowering effect of GLP-1 receptor agonists and DPP4 inhibitors, it seems that incretin-based therapies are not associated with an increase in fracture risk. Sodium-glucose co-transporter 2 inhibitors may alter calcium and phosphate homeostasis as a result of secondary hyperparathyroidism induced by increased phosphate reabsorption. Although these changes may suggest detrimental effects of SGLT-2 inhibitors on skeletal integrity, treatment-related direct effects on bone metabolism seem unlikely. Observed changes in BMD, however, seem to result from increased bone turnover in the early phase of drug-induced weight loss. Fracture risk, which is observed in older patients with impaired renal function and elevated cardiovascular disease risk treated with SGLT2 inhibitors, seems to be independent of direct effects on bone but more likely to be associated with falls and changes in hydration status secondary to osmotic diuresis.

Kyphoscoliotic type of Ehlers-Danlos Syndrome (EDS VIA) in six Egyptian patients presenting with a homogeneous clinical phenotype.

UNLABELLED: The kyphoscoliotic type of the Ehlers-Danlos syndrome (EDS VIA) is a rare recessively inherited connective tissue disorder characterized by bruisable, hyperextensible skin, generalized joint laxity, severe muscular hypotonia at birth and progressive congenital scoliosis or kyphosis. Deficiency of the enzyme lysyl hydroxylase 1 (LH1) due to mutations in PLOD1 results in underhydroxylation of collagen lysyl residues and, hence, in the abnormal formation of collagen cross-links. Here, we report on the clinical, biochemical, and molecular findings in six Egyptian patients from four unrelated families severely affected with EDS VIA. In addition to the frequently reported p.Glu326_Lys585dup, we identified two novel sequence variants p.Gln208* and p.Tyr675*, which lead either to loss of function of LH1 or to its deficiency. All affected children presented with similar clinical features of the disorder, and in addition, several dysmorphic craniofacial features, not yet described in EDS VIA. These were specific for the affected individuals of each family, but absent in their parents and their unaffected siblings. CONCLUSION: Our description of six patients presenting with a homogeneous clinical phenotype and dysmorphic craniofacial features will help pediatricians in the diagnosis of this rare disorder.

Biochemical markers for assessment of calcium economy and bone metabolism: application in clinical trials from pharmaceutical agents to nutritional products.

Nutrition plays an important role in osteoporosis prevention and treatment. Substantial progress in both laboratory analyses and clinical use of biochemical markers has modified the strategy of anti-osteoporotic drug development. The present review examines the use of biochemical markers in clinical research aimed at characterising the influence of foods or nutrients on bone metabolism. The two types of markers are: (i) specific hormonal factors related to bone; and (ii) bone turnover markers (BTM) that reflect bone cell metabolism. Of the former, vitamin D metabolites, parathyroid hormone, and insulin-like growth factor-I indicate responses to variations in the supply of bone-related nutrients, such as vitamin D, Ca, inorganic phosphate and protein. Thus modification in bone remodelling, the key process upon which both pharmaceutical agents and nutrients exert their anti-catabolic or anabolic actions, is revealed. Circulating BTM reflect either osteoclastic resorption or osteoblastic formation. Intervention with pharmacological agents showed that early changes in BTM predicted bone loss and subsequent osteoporotic fracture risk. New trials have documented the influence of nutrition on bone-tropic hormonal factors and BTM in adults, including situations of body-weight change, such as anorexia nervosa, and weight loss by obese subjects. In osteoporosis-prevention studies involving dietary manipulation, randomised cross-over trials are best suited to evaluate influences on bone metabolism, and insight into effects on bone metabolism may be gained within a relatively short time when biochemical markers are monitored.

Sexualhormone und Knochen.

Bone is a dynamic tissue that undergoes renewal and repair throughout life through the process of bone remodelling. Skeletal homeostasis is achieved through coupled and balanced bone resorption and bone formation. Several local and systemic factors regulate these processes, including sex hormones. Estrogenes and androgens influence growth, maturation and maintenance of bone mass. Sex homones act on bone through multiple mechansims. Sex hormones influence synthesis and secretion of many growth factors and cytokines, and play therefore a central role in the regulation of bone metabolism. The local and systemic regulation of bone metabolism occurs through fine tuned processes, which are influences by sex hormones and the aging process. This is evidenced by the fact that hypogonadims in both sexes is associated with bone loss an estrogen deficiency at the menopause is an important pathophysiological factor in the developement of postmenopausal osteoporosis. Treatment with aromatese inhibitors for breast cancer and antiandrogen treatment for prostate cancer are associated with an increased fracture risk and warrant increased diagnostic and treatment awareness.

Dairy in adulthood: from foods to nutrient interactions on bone and skeletal muscle health.

The risk of fragility fractures exponentially increases with aging. Reduced mass and strength of both bone in osteoporosis and skeletal muscle in sarcopenia play a key role in the age-related incidence of fragility fractures. Undernutrition is often observed in the elderly, particularly in those subjects experiencing osteoporotic fractures, more likely as a cause than a consequence. Calcium (Ca), inorganic phosphate (Pi), vitamin D, and protein are nutrients that impact bone and skeletal muscle integrity. Deficiency in the supply of these nutrients increases with aging. Dairy foods are rich in Ca, Pi, and proteins and in many countries are fortified with vitamin D. Dairy foods are important souces of these nutrients and go a long way to meeting the recommendations, which increase with aging. This review emphaszes the interactions between these 4 nutrients, which, along with physical activity, act through cellular and physiological pathways favoring the maintenance of both bone and skeletal muscle structure and function.

[Laboratory investigation of endocrine function - interpretation of results and pitfalls]. / Endokrinologische Laboruntersuchungen - wo liegen die Probleme?

Endocrine disorders are common in internal medicine. Diagnosis of endocrine diseases are usually based on patient history, clinical assessment and laboratory investigations. Thereby, biochemical analyses are used to confirm clinical diagnosis, to assess the need for treatment and to monitor disease progression, in particular to ascertain treatment efficacy. This article will focus on frequently used laboratory investigations for endocrine diseases such as diabetes, thyroid dysfunction, male hypogonadism and adrenal insufficiency. In particular, pre-analytical and analytical variability of biochemical measures as well as its significance in clinical practice will be discussed.

[Osteoporosis: evaluation, diagnosis and monitoring]. / Diagnose und Verlaufskontrolle der Osteoporose.

A paradigm change is taking place in the diagnosis of osteoporosis - away from the overemphasis on bone mineral density (BMD) as the sole gauge of need for diagnosis and treatment towards a comprehensive risk assessment of all the components of increased bone fragility. The main risk factors, and thereby reasons for further diagnostics, are previous non-traumatic vertebral and non-vertebral fractures, long-term glucocorticoid therapy, low body weight, increased risk of fall, and disorders associated with an increased fracture risk. The indication for osteoporosis therapy is based on the individual fracture risk and should not be based purely on a single BMD value. Monitoring the effectiveness of osteoporosis treatment presents a challenge in everyday clinical practice. As an alternative to fracture incidence, surrogate markers (BMD, biochemical markers of bone turnover) can be used to assess effectiveness of treatment in the individual patient. Correct employment and interpretation of surrogate markers in osteoporosis therapy requires knowledge of pre-analytical and analytical factors which co-determine the measurement methods. The purpose of this overview is to examine the possibilities of clinical investigation, BMD measurement and determination of bone turnover markers for the evaluation of therapeutic response.

Bone Microarchitecture and Strength in Long-Standing Type 1 Diabetes.

Type 1 diabetes (T1DM) is associated with an increased fracture risk, specifically at nonvertebral sites. The influence of glycemic control and microvascular disease on skeletal health in long-standing T1DM remains largely unknown. We aimed to assess areal (aBMD) and volumetric bone mineral density (vBMD), bone microarchitecture, bone turnover, and estimated bone strength in patients with long-standing T1DM, defined as disease duration ≥25 years. We recruited 59 patients with T1DM (disease duration 37.7 ± 9.0 years; age 59.9 ± 9.9 years.; body mass index [BMI] 25.5 ± 3.7 kg/m2 ; 5-year median glycated hemoglobin [HbA1c] 7.1% [IQR 6.82-7.40]) and 77 nondiabetic controls. Dual-energy X-ray absorptiometry (DXA), high-resolution peripheral quantitative computed tomography (HRpQCT) at the ultradistal radius and tibia, and biochemical markers of bone turnover were assessed. Group comparisons were performed after adjustment for age, gender, and BMI. Patients with T1DM had lower aBMD at the hip (p < 0.001), distal radius (p = 0.01), lumbar spine (p = 0.04), and femoral neck (p = 0.05) as compared to controls. Cross-linked C-telopeptide (CTX), a marker of bone resorption, was significantly lower in T1DM (p = 0.005). At the distal radius there were no significant differences in vBMD and bone microarchitecture between both groups. In contrast, patients with T1DM had lower cortical thickness (estimate [95% confidence interval]: -0.14 [-0.24, -0.05], p < 0.01) and lower cortical vBMD (-28.66 [-54.38, -2.93], p = 0.03) at the ultradistal tibia. Bone strength and bone stiffness at the tibia, determined by homogenized finite element modeling, were significantly reduced in T1DM compared to controls. Both the altered cortical microarchitecture and decreased bone strength and stiffness were dependent on the presence of diabetic peripheral neuropathy. In addition to a reduced aBMD and decreased bone resorption, long-standing, well-controlled T1DM is associated with a cortical bone deficit at the ultradistal tibia with reduced bone strength and stiffness. Diabetic neuropathy was found to be a determinant of cortical bone structure and bone strength at the tibia, potentially contributing to the increased nonvertebral fracture risk. © 2022 The Authors. Journal of Bone and Mineral Research published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research (ASBMR).

Spondylocheiro dysplastic form of the Ehlers-Danlos syndrome--an autosomal-recessive entity caused by mutations in the zinc transporter gene SLC39A13.

We present clinical, radiological, biochemical, and genetic findings on six patients from two consanguineous families that show EDS-like features and radiological findings of a mild skeletal dysplasia. The EDS-like findings comprise hyperelastic, thin, and bruisable skin, hypermobility of the small joints with a tendency to contractures, protuberant eyes with bluish sclerae, hands with finely wrinkled palms, atrophy of the thenar muscles, and tapering fingers. The skeletal dysplasia comprises platyspondyly with moderate short stature, osteopenia, and widened metaphyses. Patients have an increased ratio of total urinary pyridinolines, lysyl pyridinoline/hydroxylysyl pyridinoline (LP/HP), of approximately 1 as opposed to approximately 6 in EDS VI or approximately 0.2 in controls. Lysyl and prolyl residues of collagens were underhydroxylated despite normal lysyl hydroxylase and prolyl 4-hydroxylase activities; underhydroxylation was a generalized process as shown by mass spectrometry of the alpha1(I)- and alpha2(I)-chain-derived peptides of collagen type I and involved at least collagen types I and II. A genome-wide SNP scan and sequence analyses identified in all patients a homozygous c.483_491 del9 SLC39A13 mutation that encodes for a membrane-bound zinc transporter SLC39A13. We hypothesize that an increased Zn(2+) content inside the endoplasmic reticulum competes with Fe(2+), a cofactor that is necessary for hydroxylation of lysyl and prolyl residues, and thus explains the biochemical findings. These data suggest an entity that we have designated "spondylocheiro dysplastic form of EDS (SCD-EDS)" to indicate a generalized skeletal dysplasia involving mainly the spine (spondylo) and striking clinical abnormalities of the hands (cheiro) in addition to the EDS-like features.

[Primary hyperparathyroidism]. / Primärer Hyperparathyreoidismus.

Primary hyperparathyroidism is frequently an incidental finding in asymptomatic patients. Often the diagnosis of primary hyperparathyroidism is made in evaluation for osteoporosis, rarely in the context of hypercalcemic crisis, myopathy, kidney stones, nephrocalcinosis, and osteitis fibrosa. The most frequent cause for primary hyperparathyroidism is benign parathyroid adenoma, reminders have hyperplasia. Primary hyperparathyroidism is defined as hypercalcemia with inappropriately high parathyroid hormone levels. Surgery is the definitive treatment for patients with symptomatic primary hyperparathyroidism and asymptomatic patients, who meet one of the following criteria: serum calcium>0.25 mmol/L (1.0 mg/dl) above the accepted normal reference range, renal failure (GFR<60 ml/min) and presence of osteoporosis (T-score<-2.5 or fracture). Parathyroidectomy should be performed by an experienced surgeon. As an alternative in inoperable patients or preoperatively in severe hypercalcemia cinacalcet successfully reduces calcium levels. In asymptomatic patients not meeting the above mentioned criteria serum calcium and creatinin levels should be measured once a year and DXA every two years, since 30% of the patients with asymptomatic primary hyperparathyroidism are progressive.

Free Thyroxine Levels are Associated with Cold Induced Thermogenesis in Healthy Euthyroid Individuals.

Thyroid hormone (TH) is an important regulator of mammalian metabolism and facilitates cold induced thermogenesis (CIT) in brown adipose tissue (BAT). Profound hypothyroidism or hyperthyroidism lead to alterations in BAT function and CIT. In euthyroid humans the inter-individual variation of thyroid hormones is relatively large. Therefore, we investigated whether levels of free thyroxine (T4) or free triiodothyronine (T3) are positively associated with CIT in euthyroid individuals. We performed an observational study in 79 healthy, euthyroid volunteers (mean age 25.6 years, mean BMI 23.0 kg · m-2). Resting energy expenditure (REE) was measured by indirect calorimetry during warm conditions (EEwarm) and after a mild cold stimulus of two hours (EEcold). CIT was calculated as the difference between EEcold and EEwarm. BAT activity was assessed by 18F-FDG-PET after a mild cold stimulus in a subset of 26 participants. EEcold and CIT were significantly related to levels of free T4 (R2 = 0.11, p=0.0025 and R2 = 0.13, p=0.0011, respectively) but not to free T3 and TSH. Cold induced BAT activity was also associated with levels of free T4 (R2 = 0.21, p=0.018). CIT was approximately fourfold higher in participants in the highest tertile of free T4 as compared to the lowest tertile. Additionally, free T4 was weakly, albeit significantly associated with outdoor temperature seven days prior to the respective study visit (R2 = 0.06, p=0.037). These finding suggests that variations in thyroid hormone levels within the euthyroid range are related to the capability to adapt to cool temperatures and affect energy balance.

Impact of bisphosphonate wash-out prior to teriparatide therapy in clinical practice.

Concurrent use of bisphosphonate therapy reduces the anabolic effect of teriparatide. Consequently, in clinical practice bisphosphonates are discontinued and teriparatide therapy held for a few months to allow bone turnover to increase. We aimed to evaluate the effect of prior bisphosphonate exposure and the effect of bisphosphonate wash-out on the treatment response to teriparatide. Thirty-nine patients with primary osteoporosis (mean age 63.6 +/- 14.0 years), including 26 patients previously treated with oral bisphosphonates (median duration 53 months) and 13 bisphosphonate-naïve patients were started on teriparatide (20 mug daily) and followed prospectively over 12 months. The primary study outcome was change in bone formation markers (PINP, bone ALP, osteocalcin). Secondary outcomes included changes in bone resorption (betaCTX) and 12-month changes in BMD. Markers of bone formation increased early during teriparatide therapy and were followed by an increase in betaCTX (p < 0.001). The magnitude of the increase in bone markers was comparable in both patient groups irrespective of prior bisphosphonate exposure; similarly, increases in BMD after 12 months were not significantly different between bisphosphonate-pretreated and bisphosphonate-naïve patients (lumbar spine 7.1 vs. 8.9%, p = 0.58; total hip 4.1 vs. 1.1%, p = 0.48). The response of teriparatide was not related to the duration of bisphosphonate wash-out (median duration 4.2 months). This study confirms that beneficial effects of teriparatide on intermediate bone endpoints can be translated into clinical practice with less constringent methodological circumstances than in RCTs. Furthermore, as bisphosphonate wash-out does not appear to influence the treatment effect, teriparatide therapy can be started immediately after ceasing bisphosphonate therapy and wash-out.

Possible beneficial effect of bisphosphonates in osteonecrosis of the knee.

UNLABELLED: Osteonecrosis (ON) in the knee occurs as a localized inflammatory disease in relation to spontaneous or non-traumatic ON. Conservative treatment possibilities are limited, and prognosis appears to be poor; in most cases, ON results in knee arthroplasty. Bisphosphonates are suggested to prevent bone resorption and collapse of necrotic bone. In this observational, prospective study we investigated the effect of bisphosphonate treatment in patients with spontaneous or arthroscopy-induced ON of the knee. Twenty-eight patients with osteonecrotic lesions and bone marrow oedema in the knee were included. In 22 patients (80%), ON was identified after arthroscopic surgery of the knee; six patients were diagnosed with spontaneous ON. Patients were initially given pamidronate 120 mg i.v. divided in 3-4 perfusions over 2 weeks, followed by oral bisphosphonate treatment with alendronate 70 mg weekly for 4-6 months. Bisphosphonate treatment resulted in a rapid pain relief, VAS decreasing from 8.2 ± 1.2 at baseline to 5.02 ± 0.6 after 4-6 weeks (p < 0.001). After 6 months, the VAS decreased by 80% (p < 0.001). At the 6-month follow-up, symptoms had resolved completely in 15 patients out of 28; in 6 patients, minimal symptoms (VAS 1-2) remained. In two patients, treatment effect was unsatisfactory, and surgical intervention was needed (arthroplasty). Bone marrow oedema on MRI resolved completely in 18 patients out of 28 with substantial reduction in the remaining. Furthermore, osteonecrotic area resolved completely or demarcation with sclerotic changes of the necrotic area could be observed. Bisphosphonate treatment in patients with osteonecrosis of the knee was associated with a rapid improvement in pain score and radiological consolidation of the area of osteonecrosis. Further randomized, controlled trials are warranted to confirm the potential beneficial role of bisphosphonates in the treatment of osteonecrosis of the knee. LEVEL OF EVIDENCE: observational study, level IV.

The Connective Tissue Disorder Associated with Recessive Variants in the SLC39A13 Zinc Transporter Gene (Spondylo-Dysplastic Ehlers-Danlos Syndrome Type 3): Insights from Four Novel Patients and Follow-Up on Two Original Cases.

Recessive loss-of-function variants in SLC39A13, a putative zinc transporter gene, were first associated with a connective tissue disorder that is now called "Ehlers-Danlos syndrome, spondylodysplastic form type 3" (SCD-EDS, OMIM 612350) in 2008. Nine individuals have been described. We describe here four additional affected individuals from three consanguineous families and the follow up of two of the original cases. In our series, cardinal findings included thin and finely wrinkled skin of the hands and feet, characteristic facial features with downslanting palpebral fissures, mild hypertelorism, prominent eyes with a paucity of periorbital fat, blueish sclerae, microdontia, or oligodontia, and-in contrast to most types of Ehlers-Danlos syndrome-significant short stature of childhood onset. Mild radiographic changes were observed, among which platyspondyly is a useful diagnostic feature. Two of our patients developed severe keratoconus, and two suffered from cerebrovascular accidents in their twenties, suggesting that there may be a vascular component to this condition. All patients tested had a significantly reduced ratio of the two collagen-derived crosslink derivates, pyridinoline-to-deoxypyridinoline, in urine, suggesting that this simple test is diagnostically useful. Additionally, analysis of the facial features of affected individuals by DeepGestalt technology confirmed their specificity and may be sufficient to suggest the diagnosis directly. Given that the clinical presentation in childhood consists mainly of short stature and characteristic facial features, the differential diagnosis is not necessarily that of a connective tissue disorder and therefore, we propose that SLC39A13 is included in gene panels designed to address dysmorphism and short stature. This approach may result in more efficient diagnosis.