Diagnosis Of Low Bone Mineral Density Research Articles

P013 Serum osteoprotegerin and RANKL in patients with Juvenile Idiopathic Arthritis and their correlation with bone mineral density

Abstract Background Juvenile idiopathic arthritis (JIA) is the most common chronic rheumatic arthropathy of childhood and is associated with low bone mass, and may hasten the onset of osteoporosis later in life1. Bone loss occurs because of an imbalance between osteoclasts-activating factors like receptor activator of nuclear factor-κB ligand (RANKL) and its inhibitor osteoprotegerin (OPG) 2. Dual energy X-ray absorptiometry (DXA) is the preferred method for measuring bone mineral density (BMD) in children and to identify and follow individuals at risk for fracture 3. The objective is the Evaluation of serum levels of osteoprotegerin and RANKL and their correlation with BMD in JIA patients. Methods Forty JIA patients (according to the revised classification criteria of ILAR) and 40 healthy children individually matched for age, sex and race were included in this study. Children excluded from the study were those with primary and secondary causes of osteoporosis (such as chronic illness). All patients were assessed clinically by: age, sex, body mass index, type of JIA, disease duration and disease activity (by Juvenile Arthritis Disease Activity Score; JADAS 10). The functional disability was assessed by the Childhood Health Assessment Questionnaire (CHAQ). Blood samples were collected from JIA patients and healthy controls to determine serum levels of OPG and RANKL by ELISA. DXA scans were done using GE Healthcare Lunar DPX, Madison, Wisconsin. Bone mineral density of the L1-L4 lumbar spine and total body less head (TBLH) was evaluated in g/cm2 and expressed as Z score for age, sex according to the reference data given for this equipment. Results The study included 40 patients (25 females) with a mean age of 11.14 years and median disease duration of 2.5 years. As regard JIA type, 45% of patients were oligoarticular, 32.5% were polyarticular, and 22.5% were systemic JIA. Median JADAS 10 was 13.95. Patients (especially polyarticular JIA) had significantly higher serum RANKL levels and lower serum OPG and OPG/RANKL ratio when compared with controls (with p-value <0.001, 0.032 and <0.001 respectively). A diagnosis of low BMD (BMD Z-score ≤ -2) was given in 25% of patients (15% polyarticular and 10% systemic) by DXA of lumbar spine, and 20% (10% polyarticular and 10% systemic) by DXA of TBLH. On the other hand, no patient was given a diagnosis of osteoporosis (BMD Z-score ≤ -2 and a significant fracture history). Low BMD at lumbar spine and TBLH was negatively correlated with serum RANKL while positively correlated with OPG/RANKL ratio. Moreover, low BMD at lumbar spine was positively correlated with serum OPG level Conclusion High RANKL and low OPG levels appear to be associated with low bone mass in JIA patients. Patients with JIA (especially polyarticular and systemic subtype) are at increased risk of low bone mineral mass. Disclosure of Interests None declared

Prevalence of low bone mineral density in Human Immunodeficiency Virus-infected patients and its correlation with other determinants

Background: The patients infected with human immunodeficiency virus (HIV) are potentially at risk of low bone mineral density (BMD). The present study was done to find out the prevalence of low BMD in HIV-infected patients and its correlation with other factors such as gender, body mass index (BMI), CD4 count, and highly active antiretroviral therapy (HAART). Methods: This was an observational cross-sectional study conducted in a tertiary care center for 1 year period. A total of 127 HIV-infected patients were evaluated for BMD by dual-energy X-ray absorptiometry (DEXA) scans at two sites lumbosacral spine and bilateral neck femur. Correlation with other factors was also studied. Results: The diagnosis of low BMD was established in 105 (82.67%) patients. Osteoporosis (44.1%) was more common than osteopenia (38.6%) at the lumbosacral spine. The mean T score of the DEXA lumbar spine and bilateral neck femur was observed to be ?2.113 and ?1.379, respectively. Males (88.73%) had low BMD than females (75%). Approximately 94.5% of subjects having BMI <18 had low BMD in contrast to 80.8% among subjects having BMI >18. After treatment, 47 patients had CD4 count <400 and 80 > 400. Forty-three patients out of 47 (91.5%) had low BMD and 62 out of 80 (77.5%) had low BMD. Conclusion: Low BMD is prevalent in HIV-infected subjects. Low BMI, persistently low CD4 count, tenofovir containing HAART regimen showed a positive correlation with low BMD. Hence, HIV infection should be considered as a risk factor for bone disease.

Effect of T12 Mislabeling as L1 on the Diagnosis of Low BMD at Lumbar Spine

Mislabeling of T12 vertebra as L1 has been shown to reduce L1-L4 bone mineral density (BMD). However, the effect of such mislabeling on the L1-L4 BMD and prevalence of osteoporosis and/or osteopenia in a clinical setting is not known. The study aimed to the effect of mislabelling of T12 as L1 on the L1-L4 BMD and diagnosis of osteoporosis and/or osteopenia. It is a retrospective study done at a tertiary health care center in South India. Database of dual X-ray absorptiometry machine at our center was reviewed and BMD data of men aged more than 50 years and postmenopausal women who underwent BMD during the last 3.5 years were included in the analysis. A total of 570 subjects had undergone BMD testing at the lumbar spine of whom images of the T12 and lower part of the T11 were available for 293 subjects. Six of these with ≤1 eligible vertebra for the calculation of L1-L4 BMD were further excluded from the analysis. The BMD data of the remaining 287 subjects were noted. Later T12 was labeled as L1 and a new set of BMD data was obtained. Using the WHO classification, BMD status was classified as normal BMD, osteopenia, and osteoporosis for both the analyses. L1-L4 BMD (0.916 ± 0.163 vs 0.937 ± 0.170, p < 0.0001) and T-scores of L1-L4 (-2.23 ± 1.37 vs -2.06 ± 1.43, p < 0.0001) with mislabeling were significantly lower than those measured with correct labeling. BMD status was misclassified by T12 mislabelling as L1 in a total of 30 (10.4%) individuals. Inter-rater agreement between the 2 scenarios for the diagnosis of osteoporosis, osteopenia, and normal BMD was substantial (weighted Kappa: 0.87 [95%CI: 0.83-0.91]). To conclude, mislabeling of T12 as L1 significantly reduces L1-L4 BMD. However, the diagnosis of BMD status by mislabeling has a substantial agreement with that obtained with correct labeling.

Osteonecrosis of the Femoral Head in an 8-Year Old Boy: Appraisal of Evolution by DXA.

Assessment of skeletal status and bone mineral density (BMD) in the pediatric population requires knowledge of the child’s overall health, clinical history of chronic illness and/or risk factors for osteoporosis, and atraumatic fractures. Dual-energy X-ray absorptiometry (DXA) is the gold standard for the assessment of bone health, in children and adolescents. The interpreting physician needs to acknowledge that diagnosis of low BMD in growing subjects should include in addition to densitometric measurements, the synchronous assessment of the DXA-generated image for collateral findings that may cause erroneous evaluation of bone mass and improper management.

Bone Mineral Density in Moroccan Patients with Juvenile Idiopathic Arthritis

Aim: The aim of this study was to evaluate the bone mineral density (BMD) in Moroccan patients with juvenile idiopathic arthritis and its correlates with disease parameters and vitamin D status. Methods: Forty patients with juvenile idiopathic arthritis (JIA) were included in a cross-sectional study. The diagnosis of JIA was made according to the criteria of the International League of Association of Rheumatology (ILAR). Information on disease activity, quality of life, sex, age, age at diagnosis, duration of medication use and bone fractures were collected by use of a standardized questionnaire. Patients underwent anthropometric assessment, puberty staging and BMD assessment by dual energy X-ray absorptiometry of the lumbar spine, and total body. Bone mineral density (in g/cm2) was expressed in Z-scores, the number of standard deviation above or below the mean value of an age- and sex-matched reference population. In children, low BMD was defined as a Z-score less than -2 and osteoporosis was defined as a Z-score less than-2 with a fracture history. The daily intake of calcium was determined by the translated version in Moroccan Arabic language of Fardellone questionnaire. Laboratory evaluations included serum calcium, phosphate, alkaline phosphatase, 25-hydroxyvitamin D were assessed. Results: Forty children with JIA were included (22 male, 18 female); the mean of age of the patients was 11 ± 4.23 years. The median of disease duration was 2 years [1-5]. Eighteen (45%) patients had polyarticular JIA and 60% used corticosteroids.Twenty patients (50%) were given a diagnosis of low BMD and no patient was given a diagnosis of osteoporosis. Bone mineral density Z score in lumbar spine showed a statistically significant correlation with cumulative dose of corticosteroids (β=-0.40, p=0.05) and systemic subtype of JIA (β=-1.07, p=0.01) and the BMD in total body showed a statistically significant correlation with weight (β=0.40, p=0.009) and height (β=0.37, p=0.01). However, there was no significant association in our study between the BMD and disease duration, daily intake of calcium, and 25-hydroxyvitamin D. Conclusion: This study suggests that osteopenia was a frequent complication