Practical Considerations for the Clinical Application of Bone Turnover Markers in Osteoporosis.

Bone turnover markers (BTMs) are released during the bone remodelling cycle and are measurable in blood or urine, reflecting bone remodelling rate. They have been useful in elucidating the pharmacodynamics and effectiveness of osteoporosis medication in clinical trials and are increasingly used in routine clinical management of osteoporosis, especially for monitoring therapy, in addition to their use in other metabolic bone disease such as Paget's disease of bone and osteomalacia. Serum ß isomerised C-terminal telopeptide of type I collagen and pro-collagen I N-terminal propeptide have been designated as reference BTMs for use in osteoporosis. In addition, bone-specific isoenzyme of alkaline phosphatase (B-ALP) secreted by osteoblasts and tartrate-resistant acid phosphatase 5b (TRACP-5b) secreted by osteoclasts are also found to be specific markers of bone formation and resorption, respectively. The concentrations of the latter enzymes in blood measured by immunoassay provide reliable measures of bone turnover even in the presence of renal failure. B-ALP is recommended for use in the assessment of renal bone disease of chronic kidney disease, and TRACP-5b shows promise as a marker of bone resorption in that condition. BTMs in blood do not suffer from biological variation to the same extent as the older BTMs that were measured in urine. Appropriate patient preparation and sample handling are important in obtaining accurate measures of BTMs for clinical use. Reference change values and treatment targets have been determined for the reference BTMs for their use in monitoring osteoporosis treatment. Further ongoing studies will enhance their clinical applications.

Transient Hyperphosphatasemia in a Child with Autism Spectrum Disorder.

INTRODUCTION: Autism spectrum disorder (ASD) is a neurodevelopmental disorder characterized by deficits in social communication and the presence of restricted interests and repetitive behaviors. Transient hyperphosphatasemia of infancy and early childhood (THI) is a benign laboratory disorder characterized by transiently extremely elevated activity of serum alkaline phosphatase (S-ALP). CASE REPORT: We present a 21-month-old girl with a right leg limp, most probably due to reactive arthritis after febrile viral infection, and deterioration of psychomotor development with concomitant transient elevation of S-ALP (61.74 µkat/L; normal 2.36-7.68 µkat/L). Normal values of serum creatinine, aspartate-aminotransferase, alanin-aminotransferase, calcium, phosphate, together with normal wrist X-ray ruled out rickets or other bone or hepatic cause of high S-ALP. The S-ALP gradually decreased within 3 months, thus fulfilling the THI criteria. Screening for inborn errors of metabolism was negative and meticulous neurologic, psychologic and psychiatric assessment pointed to the diagnosis of autism spectrum disorder (ASD). There was no causal relationship between THI and ASD, as high S-ALP was an accidental and transient finding within the routine laboratory assessment. However, when THI occurs in a child with an onset of a new disorder, or with a pre-existing bone or liver disease, it might seriously concern the physician. CONCLUSION: Children with THI should be spared from extensive evaluations and unnecessary blood draws.

A proposed Common Training Framework for Specialists in Laboratory Medicine under EU Directive 2013/55/EC (The Recognition of Professional Qualifications).

European Union (EU) Directive 2013/55/EC (The Recognition of Professional Qualifications) allows Member States to decide on a common set of minimum knowledge, skills and competences that are needed to pursue a given profession through a Common Training Framework. To be adopted the framework must combine the knowledge, skills and competences of at least one third of the Member States. Professionals who have gained their qualifications under a Common Training Framework will be able to have these recognised automatically within the Union. The backbone of the European Federation of Clinical Chemistry and Laboratory Medicine's (EFLM) proposed Common Training Framework for non-medical Specialists in Laboratory Medicine is outlined here. It is based on an Equivalence of Standards in education, training, qualifications, knowledge, skills, competences and the professional conduct associated with specialist practice. In proposing the recognition of specialist practice EFLM has identified 15 EU Member States able to meet Equivalence and in whom the profession and/or its training is regulated (an additional EU Commission requirement). The framework supports and contributes to the Directive's enabling goals for increasing professional mobility, safeguarding consumers and ensuring a more equitable distribution of skills and expertise across the Member States. It represents EFLM's position statement and provides a template for professional societies and/or competent authorities to engage with the EU Commission.

Algorithm for the Use of Biochemical Markers of Bone Turnover in the Diagnosis, Assessment and Follow-Up of Treatment for Osteoporosis.

INTRODUCTION: Increased biochemical bone turnover markers (BTMs) measured in serum are associated with bone loss, increased fracture risk and poor treatment adherence, but their role in clinical practice is presently unclear. The aim of this consensus group report is to provide guidance to clinicians on how to use BTMs in patient evaluation in postmenopausal osteoporosis, in fracture risk prediction and in the monitoring of treatment efficacy and adherence to osteoporosis medication. METHODS: A working group with clinical scientists and osteoporosis specialists was invited by the Scientific Advisory Board of European Society on Clinical and Economic Aspects of Osteoporosis, Osteoarthritis and Musculoskeletal Diseases (ESCEO). RESULTS: Serum bone formation marker PINP and resorption marker ßCTX-I are the preferred markers for evaluating bone turnover in the clinical setting due to their specificity to bone, performance in clinical studies, wide use and relatively low analytical variability. BTMs cannot be used to diagnose osteoporosis because of low sensitivity and specificity, but can be of value in patient evaluation where high values may indicate the need to investigate some causes of secondary osteoporosis. Assessing serum levels of ßCTX-I and PINP can improve fracture prediction slightly, with a gradient of risk of about 1.2 per SD increase in the bone marker in addition to clinical risk factors and bone mineral density. For an individual patient, BTMs are not useful in projecting bone loss or treatment efficacy, but it is recommended that serum PINP and ßCTX-I be used to monitor adherence to oral bisphosphonate treatment. Suppression of the BTMs greater than the least significant change or to levels in the lower half of the reference interval in young and healthy premenopausal women is closely related to treatment adherence. CONCLUSION: In conclusion, the currently available evidence indicates that the principal clinical utility of BTMs is for monitoring oral bisphosphonate therapy.

Calcemia and Inflammatory Markers in Early-Onset Neonatal Infection.

INTRODUCTION: Ionised hypocalcemia (S-Ca2+) has been repeatedly observed in neonates with sepsis. Our aim was to evaluate total calcemia (S-Ca) and its relationship to laboratory markers of infection. METHODS: We retrospectively evaluated total calcemia (S-Ca) and its relationship to laboratory markers of sepsis/infection (serum levels of C-reactive protein - S-CRP and procalcitonin - S-PCT) in 29 full-term neonates with early-onset neonatal infection hospitalized at our neonatology ward between 2012 and 2016. The control group consisted of 705 neonates without infection. RESULTS: In neonates with early-onset infection , the S-Ca on day 1, 2 and 3 was significantly lower (p < 0.0001; p < 0.0001; p = 0.05 versus controls) same as the pooled S-Ca (p < 0.0001 versus controls). There was a weak negative correlation between pooled S-Ca and S-PCT, or pooled S-Ca and S-CRP (r = -0.22, p = 0.06; r = -0.19, p = 0.09). CONCLUSION: S-Ca was decreased in neonates with early-onset infection and did show a slight tendency to inverse correlation with S-CRP and S-PCT. Pediatricians must be aware of the fact that a drop in total S-Ca should alert their attention to the risk of neonatal infection, and, likewise, that the children with neonatal infection are at a higher risk of hypocalcemia with all its consequences.

Three cases of transient neonatal pseudohypoparathyroidism.

Neonatal hypocalcemia is defined as serum calcium (S-Ca) < 2.0 mmol/l in full-term newborns and <1.75 mmol/l in preterm newborns. Neonatal hypocalcemia is either early onset (<3 days of age) or late onset (>3 days of age). Newborns with hypocalcemia are often asymptomatic but may present with hypotonia, apnea, poor feeding, jitteriness, seizures, and cardiac failure. Signs of hypocalcemia rarely occur unless S-Ca drops below 1.75 mmol/l. Neonatal hypocalcemia can be a result of hypoparathyroidism (transient or primary), increased serum calcitonin, sepsis, asphyxia, hepatopathy, hypomagnesemia, high phosphate load, transient hypoparathyroidism, and, rarely, transient neonatal pseudohypoparathyroidism [transient resistance to biological actions of parathyroid hormone (PTH)]. We present the case of three boys (two with gestational age 39 weeks, one 36 weeks; none of them with either asphyxia or sepsis) with mild hypotonia, where S-Ca in the range of 1.67-1.9 mmol/l was detected within the first 3 days of life, together with hyperphosphatemia [serum phosphate (P) 2.5-2.6 mmol/l], normomagnesemia [serum magnesium (S-Mg) 0.77-0.88 mmol/l], normal alkaline phosphatase (ALP) activity (2.8-4.5 µkat/l), and high serum PTH (40-51 pg/ml; normal = 5-28). In spite of the gradual increase of S-Ca, the elevated serum PTH persisted beyond days 3, 4, and 6 in all three boys, together with normal or low-to-normal S-Ca, high or normal-to-high serum P, and no increases in serum ALP. The mothers S-Ca, P, Mg, ALP, and PTH levels were within normal reference ranges. With regard to laboratory results, the diagnosis of transient neonatal pseudohypoparathyroidism (due to immaturity of PTH-receptors) is highly probable in these three neonates.

Effects of selenium and tellurium on the activity of selenoenzymes glutathione peroxidase and type I iodothyronine deiodinase, trace element thyroid level, and thyroid hormone status in rats.

Tellurium (Te) and selenium (Se) belong chemically to the VIa group of elements. Se represents an essential element closely related to thyroid function. Te has growing application in industrial processes. Little is known about the Te biological activity, particularly with respect to potential chemical interactions with Se-containing components in the organism. In this study, female Wistar rats (body weight: 115-120 g) received sodium selenite pentahydrate (10 mg/L) or sodium tellurite (9.4 mg/L) in drinking water for 6 wk. Additional groups of rats received their combination with zinc sulfate heptahydrate (515 mg/L). The stimulation of 5'-DI-I activity due to selenite (to 158%, p<0.01) or tellurite treatment (to 197%, p<0.01) was seen; however, no effect on glutathione peroxidase was demonstrated in this experiment. An elevation of T4, T3, and rT3 serum levels was measured in the Se+Te-treated group; T4 and rT3 levels were elevated in the Te+Zn-treated group. Te accumulates in the thyroid gland and influences the zinc thyroid level. Te treatment alone and in combination with Se or Zn decreased the iodine thyroid concentration to 65-70% of the control value. Further studies are needed to clarify the nature and effects of these events.

Effect of L-carnitine supplementation on secondary hyperparathyroidism and bone metabolism in hemodialyzed patients.

The aim of our work was to test the influence of L-carnitine supplementation on secondary hyperparathyroidism and bone metabolism in hemodialyzed patients in a randomized study. Eighty-three chronically hemodialyzed patients were observed; 44 were supplemented with L-carnitine (15 mg/kg intravenously after each hemodialysis for 6 months), while 39 took placebo. Levels of free carnitine (CAR), calcium (Ca), inorganic phosphate (P), Ca x P product, parathormone (PTH), bone-specific alkaline phosphatase (b-ALP), osteocalcin (OC), and osteoprotegerin (OPG) were monitored. In comparison with pretreatment values, changes of some selected parameters occurred in the supplemented patients after 6 months (data are expressed as medians; NS, nonsignificant change): PTH, 186.0 vs. 135.5 ng/L (NS); b-ALP, 13.9 vs. 13.2 microg/L (P < 0.05); OC, 78.3 vs. 68.8 microg/L (NS); OPG, 144.0 vs. 182.0 ng/L (P < 0.05). In the controls, there were the following changes: PTH, 148.0 vs. 207.0 ng/L (NS); b-ALP, 15.2 vs. 13.2 microg/L (P < 0.05); OC, 62.7 vs. 79.8 microg/L (P < 0.05); OPG, 140.0 vs. 164.0 ng/L (NS). A significant correlation was found between CAR and OPG changes (r = 0.51, P < 0.001) in the supplemented patients. The supplementation led to a significant increase of serum OPG concentration. Nevertheless, we observed only nonsignificant tendencies to correction of secondary hyperparathyroidism and reduction of bone turnover in hemodialyzed patients supplemented with L-carnitine in contrast to controls. At this point, the use of L-carnitine does not seem to be justified.

Hypothyroidism in coronary heart disease and its relation to selected risk factors.

INTRODUCTION: Hypothyroidism (HT) has been found a predictor of cardiovascular diseases. We aimed to ascertain the prevalence of HT in patients with manifest coronary heart disease (CHD), and to establish its association with conventional risk factors. METHODS: 410 patients, 6-24 months after hospitalization for acute coronary syndrome, and/or revascularization, were included into the cross-sectional study. RESULTS: The prevalence of thyroid dysfunction was found in males and females as follows: overt HT, ie, thyroid stimulating hormone (TSH) > 3.65 mIU/L and free thyroxine (fT4) < 9 pmol/L and/or L-thyroxine substitution, in 2.6% and 8.4%, respectively; subclinical HT (TSH > 3.65, fT4 9-23 and no substitution) in 4.3% and 15.0%, respectively. Higher prevalence of HT was found in females with hypercholesterolemia, and in males and females with concomitant positive thyroid peroxidase antibodies. Hypothyroid subjects had higher total homocysteine in both genders and von Willebrand factor in males only. Hypothyroid females had higher total and LDL cholesterol, and were more often treated for diabetes. CONCLUSIONS: HT was found highly prevalent in patient with clinical coronary heart disease, mainly in females, and was associated with several cardiovascular risk factors.

Effect of alendronate therapy in children with osteogenesis imperfecta.

OBJECTIVE: To evaluate the effect of orally administered alendronate in children with osteogenesis imperfecta. METHODS: Thirty children (16 girls and 14 boys; mean age at baseline 10.7 +/- 6.0 years; range 4-16 years) with osteogenesis imperfecta type I (n = 22), III (n = 2), or IV (n = 6) were treated with alendronate (5 mg/day in patients aged 4-10 years and 10 mg/day in children >10 years of age) for 3 years. RESULTS: After 1 year of alendronate therapy we observed a significant increase in areal and volumetric bone mineral density Z-scores (from -2.03 +/- 1.51 to -1.04 +/- 1.20, and from -1.91 +/- 1.38 to -1.33 +/- 1.30, respectively, P < 0.001), together with a significant drop in fracture rate (from 3.77 +/- 1.57 to 0.13 +/- 0.57, P < 0.000001), relief of chronic pain (from 3.83 +/- 1.44 days of pain/week to 0.73 +/- 0.77, P < 0.000001) and improvement in ambulation/mobility (P < 0.00002). After additional 2 years of therapy there were no further significant changes in these parameters, however the improvement was still remarkable in comparison to the pretreatment values (P < 0.003, P < 0.004, P < 0.000001, P < 0.000001 and P < 0.00001, respectively). A significant drop in markers of bone turnover (urinary deoxypyridinoline and serum osteocalcin) occurred after 3 years of therapy (P < 0.003 and 0.004, respectively). No adverse reactions were observed throughout the treatment. CONCLUSIONS: Alendronate has positively influenced quality of life in paediatric patients with osteogenesis imperfecta. Bisphosphonate therapy should be used only in the context of a well-defined protocol.

Fibrate treatment and prevalence risk of mild hyperhomocysteinaemia in clinical coronary heart disease patients.

BACKGROUND: Several prospective studies reported that fibrates might increase blood total homocysteine (tHcy). In this study we aimed to establish whether the reported fibrate treatment was associated with an increased risk of mild hyperhomocysteinaemia in patients with clinical coronary heart disease, and to establish whether confounding variables may influence this effect. DESIGN: A retrospective, case-control analysis. METHODS: A total of 410 patients, 301 males and 109 females, mean age 59.2 were examined in a Czech sample from the EUROASPIRE II survey. In addition to examinations and measurements, defined by the protocol, we estimated serum total homocysteine (tHcy), folate, B12 vitamin and methylenetetrahydrofolate reductase (MTHFR) genotypes. RESULTS: We found significantly higher tHcy concentrations in patients with reported treatment with fibrate (16.6 +.- 0.66 micromol/l) compared with no lipid-lowering treatment (13.5 +/- 0.64 micromol/l, P<0.001) or to statin (12.4 +/- 0.39 micromol/l, P<0.001). Concentrations of tHcy > or =15 mmol/l (i.e. mild hyperhomocysteinaemia) as a dependent variable were positively associated with age (OR 1.18, P<0.0003), serum vitamin B12 (OR 0.87, P<0.003), serum creatinine (OR 1.35, P<0.0001 and treatment with fibrates (OR 1.30, P<0.0001), using multiple regression. Using unifactorial or multifactorial analyses, association between fibrate and tHcy is independent from conventional confounders such as age, gender, smoking, folate or B12 concentration, serum creatinine and MTHFR genotypes, however interference of low folate or B12 and fibrate treatment resulted in concentrations of tHcy more than 20 micromol/l. CONCLUSIONS: Fibrate treatment was associated with a significant increase in prevalence of the risk of mild hyperhomocysteinaemia in coronary patients, independently from conventional confounders.

Fenofibrate-induced hyperhomocysteinemia may be prevented by folate co-administration.

OBJECTIVES: Several prospective studies reported that fibrates might increase blood total homocysteine (tHcy) concentrations. Because of this adverse effect, elevated tHcy could potentially compromise the cardiovascular benefit resulting from lipid-lowering by fibrates. In our study we aimed to find out whether the folate co-administration would modify the fibrate-induced elevation of tHcy. METHODS: Twenty-four volunteers (m 17, f 7; mean age 54.9 years) with total cholesterol > or =6 mmol/L and triglycerides less than 5 mmol/L, with normal blood pressure, normal blood glucose and without any pharmacotherapy and/or clinical vascular or metabolic disease, were included in an open, randomised, prospective, crossover study. We measured lipids, tHcy, folate, vitamin B12 and renal function markers after diet, after a 6-month administration of 200 mg of fenofibrate (3 months in monotherapy followed by 3 months in combination with 10 mg of folate) and further on after an identical period of fluvastatin administration (3 months of 40 mg followed by 3 months of 80 mg). RESULTS: Fenofibrate in monotherapy, beside the expected lipid-lowering effect, increased tHcy from 10.0 to 14.2 microM/L ( p<0.001). Co-administration of folate decreased tHcy to 10.6 microM/L. In contrast, fluvastatin did not significantly influence the tHcy concentrations. CONCLUSION: Co-administration of folate to fenofibrate therapy has the potential to reverse the fibrate-induced elevation of tHcy.