Relation between homocysteine, folate, vitamin B12 and MTHFR C677T polymorphism and bone turnover markers in postmenopausal women

To investigate the association between total Homocysteine [tHcy] levels with bone turnover markers and lumbar spine BMD, and to study the influences of MTHFR genotypes and B-vitamins on tHcy and BMD in a group of Egyptian postmenopausal women. 66 Egyptian postmenopausal women were subjected to clinical assessment and lumbar spine BMD measurement. Venous blood samples were collected to measure the levels of plasma tHcy, plasma folate, vitamin B12, osteocalcin, serum cross-linking telopeptide of type I collagen [S-CTX] and the MTHFR C677T genotyping. According to the T-score, the participants were divided into three groups: normal [N], osteopenic [OPN] and osteoporotic [OPR]. tHcy levels were statistically significantly higher, and serum folate levels statistically significantly lower in the OPR group compared to the other two groups. Nonsignificant differences between the three groups regarding vitamin B12 levels and percentage of the 3 MTHFR genotypes were found. Osteocalcin and the S-CTX levels were statistically significantly higher in the OPR group than the other two groups. BMD was statistically significantly positively correlated with folate and negatively correlated with tHcy, Osteocalcin and S-CTX, while was nonsignificantly correlated with vitamin B12 levels. tHcy was statistically significantly negatively correlated with folate and positively correlated with Osteocalcin and S-CTX, while was nonsignificantly correlated with vitamin B12. The MTHFR genotype groups were not associated with the BMD, tHcy, folate or vitamin B12 levels. In postmenopausal women, tHcy and folate could be related to lumbar spine BMD while vitamin B12 and the MTHFR genotypes seem not to have relation to BMD

Diagnostic and clinical value of anti-citrullinated cyclic peptide antibodies in rheumatoid arthritis

Antibodies directed to citrulline-containing proteins have been shown to be specific for rheumatoid arthritis [RA]. They may be related to disease activity and extent of joint damage. To investigate the value of anti-citrullinated cyclic peptide antibodies [anti-CCP] in diagnosis and clinical evaluation of RA patients compared with rheumatoid factor [RF] isotypes [IgG-, IgA- and IgM-RF. In a cross-sectional study, anti-CCP and RF isotypes were assayed by ELISA in 44 RA patients, 25 patients with arthritis other than RA and 15 healthy controls. RA disease activity was assessed as mild [18 patients], moderate [15 patients] or severe [11 patients] using DAS 28 score. Bone involvement in RA was classified radiologically [recent radiographs for hands and wrists] into 3 categories: no bone involvement [16 patients], juxta-articular osteoporosis [13 patients] or joint erosions [15 patients]. According to disease duration, those with duration less than one year were grouped as early RA [17 patients] and those with duration more than one year as established RA [27 patients]. Sensitivity of anti-CCP was 72.7%; non significantly different [p>0.05] from those of IgM-RF [63.6%] or cumulative RF isotypes [75%] and significantly higher [p<0.05] than IgA- [47.7%] and IgG-RF [36.4%]. Specificity of anti-CCP was 100%; significantly higher [p<0.05] than those of IgA- [92.5%], IgG- [87.5%], IgM-RF [80%] and cumulative RF isotypes [70%]. Positive predictive value of anti-CCP was 100%; significantly higher [p<0.05] than those of IgA- [87.5%], IgM-[77.8%], IgG-RF [76.2%] and cumulative RF isotypes [73.3%]. Negative predictive value of anti-CCP was 76.9%; non significantly different [p>0.05] from those of cumulative RF isotypes [71.8%] or IgM-RF [66.7%] and significantly higher [p<0.05] than those of IgA- [61.7%] and IgG-RF [55.6%]. Anti-CCP positivity in RA patients with bone erosions was 100%; significantly higher [p<0.05] than those of cumulative RF istypes [93.3%], IgM- [86.7%], IgA- [86.7%] and IgG-RF [46.7%]. Anti-CCP positivity in patients with severe disease activity was 90.9%; non significantly higher [p>0.05] than cumulative RF isotypes [81.8%] and significantly higher [p<0.05] than those of IgA- [72.7%], IgM- [54.5%] and IgG-RF [27.3%]. Anti-CCP and RF isotypes positivity in early RA were non significantly different from those in established RA. Of special diagnostic value was the detection of positive anti-CCP in 72.2% [8/11] of RA patients in whom all RF isotypes were negative. This was especially signified in RA patients with bone erosions, severe disease activity or established. Anti-CCP proved to be a powerful diagnostic tool in RA especially in RF negative patients. It can be potentially useful as prognostic index for bone involvement and disease activity