Assessment of low vitamin D among Saudi Arabians. Did we overshoot the runway?

To compare the performance of 3 commonly used 25-hydroxyvitamin D [25-OHD] assays among a sample of the Saudi population. This cross-sectional study was carried out between January 2011 and December 2012 at King Fahd Hospital of the University, Al-Khobar, Saudi Arabia. After informed consent, blood samples for measurement of 25-OHD level was extracted from 200 adults. The vitamin D level of each individual were determined using chemiluminescence immunoassay [CLIA], radio-immuno assay [RIA], and liquid chromatography-tandem mass spectrometry [LC-MS/MS] assay. Assays were also compared through commonly used cut-points for classification of vitamin D deficiency. Bias between assays was evaluated using Bland-Altman plots. The average age of patients was 45.7 +/- 16.1 years. A significant difference between the assays was found. The mean 25-OHD levels were highest for the LC-MS/MS [21.65 ng/mL, 95% CI 19.74-23.56], intermediate for RIA [16.607 ng/mL, 95% CI 14.87-18.32], and lowest for CLIA method [13.864 ng/mL, 95% CI 12.109-15.618]. Using 30 ng/mL as a cutoff value, only 6% was found to have normal levels of 25-OHD using CLIA, 9% using RIA, and 22% using LC-MS/MS. Levels of 25-OHD and the prevalence of vitamin D deficiency are dependent on the assay used. The reported high prevalence of hypovitaminosis D among the Saudi population can be partially explained by the use of assays that underestimate vitamin D levels

Are We Missing Osteoporosis-Related Vertebral Fractures in Men?

STUDY DESIGN: Retrospective study. PURPOSE: To assess the prevalence of osteoporosis related spinal fractures among Saudi Arabian males. OVERVIEW OF LITERATURE: Vertebral fractures are the most common complication of osteoporosis and is the first sign in both sexes and only 25 to 30% of radiographically observed vertebral deformities are recognized. METHODS: We analyzed the chest radiographs of consecutive Saudi Arabian men > or = 50 years and who visited the emergency room of King Fahd University Hospital, Al Khobar, Saudi Arabia for a period of 12 months between November 1, 2007 and October 31, 2008. The site and type of fractures were classified as per the semi-quantitative technique. The other data retrieved from the medical records of patients included medications and clinical investigations for osteoporosis. RESULTS: Nine hundred seventy chest radiographs were performed during the study period and 876 radiographs could be analyzed. One hundred fifteen patients (13.1%) had 157 fractures. The mean age was 67.85 +/- 10.1 years. There was more than one fracture in 21 patients (18.2%). The majority of fractures (n = 102, 64.9%) were observed in thoracic spine. Seventy-one (45.2%) fractures were classified as mild, 54 (34.4%) were moderate and 32 (20.4%) were severe. For 26 (22.6%) patients, the report of the radiologist highlighted the fracture. CONCLUSIONS: Saudi Arabian males with osteoporosis continue to be missed despite the high prevalence osteoporosis leading to vertebral fractures. We believe it is important for physicians to identify vertebral fractures early and treat then appropriately before an extremity fracture occurs with high mortality.

Genetic Markers for Idiopathic Scoliosis in Arab Population: A Pilot Study

STUDY DESIGN: Cross-sectional screening. PURPOSE: This study was conducted to determine if there is any association of the three microsatellite markers on chromosome 19p 13.3 in unrelated Saudi Arabian girls who were suffering with adolescent idiopathic scoliosis (AIS) and their healthy siblings. OVERVIEW OF LITERATURE: The genetic influence on the development of familial scoliosis has been previously described, but the genetic influence on AIS still remains unknown. Three microsatellite markers (D19S216, D19S894, and DS1034) of chromosome 19p 13.3 were reported to be significantly associated with familial scoliosis. This cross-sectional screening was carried out in AIS patients and their siblings. METHODS: For eleven Saudi Arabian girls who were treated for AIS and their 11 siblings, we performed a linkage analysis using parametric and nonparametric methods and using GENEHUNTER ver. 2.1. Multipoint linkage analysis was used to specify an autosomal dominant trait with a gene frequency of 0.01 at the genotypic and the allelic levels. One sided Fisher's exact tests were used in the analysis of the contingency tables for the D19S216, D19S894 and DS1034 markers. RESULTS: The analysis between the patient group and the healthy siblings showed that at the genotypic level there was a significant association of the markers and scoliosis (D19S894 [p=0.036], D19S216 [p=0.004], and DS1034 [p=0.013]). Yet at the allelic level, there was no statistically significant association of the markers between the AIS patients and their siblings. CONCLUSIONS: Our pilot study shows that there is a genetic influence between the AIS patients and the siblings. We believe large scale genetic screening is warranted for the patients with AIS to identify beyond any doubt the influence of these markers.