The relationship between CRP gene polymorphism (rs2794521, rs3091244), ASDAS-CRP and ASDAS-ESR in ankylosing spondylitis

Association of C-reactive protein polymorphisms with serum-CRP concentration and viral load among dengue-chikungunya mono/co-infected patients

India being endemic to Dengue (DENV) and chikungunya (CHIKV) infections faces high patient-mortality and morbidity with overlapping clinical features. C-reactive protein (CRP) acts as early defence system in response to these infections. This study investigated role of CRP single-nucleotide polymorphism (SNP) genotypes and protein levels towards DENV/CHIKV mono and co-infection among eastern Indian patients. 128 DENV-CHIKV co-infected, 206 DENV and 167 CHIKV mono-infected patients were subjected to genotyping of two CRP SNPs by PCR-RFLP along with 102 healthy individuals. CRP levels were determined by immunoturbidimetry. Statistical correlation of CRP genotypes with CRP concentration, DENV-CHIKV mono/co-infection and viral load was performed. Patients with rs3093059-CT and rs3091244-TT were more susceptible to DENV-CHIKV co-infection, whereas, rs3091244-CT might have imparted protection against CHIKV mono-infection. DENV-HVL was more prevalent within rs3093059-TT and rs3091244-CT co-infected patients, whereas, CHIKV-HVL among rs3091244-CC. Acute phase co-infected patients had significantly higher CRP level compared to mono-infections. Both mono and co-infected patients with aches/pain exhibited 2-3-fold higher CRP levels compared to those without. rs3093059-CT and rs3091244-CT co-infected patients had higher CRP concentration compared to rs3093059-TT and rs3091244-CC, respectively. Co-infected patients with WHO-defined warning signs had higher anti-dengue IgG/IgM ratio and serum CRP level compared to those without warning signs. Thus, patient's CRP genotype might play significant role in determining serum-CRP concentration, viral load and DENV-CHIKV mono/co-infection.

The serum C-reactive protein to prealbumin ratio and fibrinogen to prealbumin ratio are two relevant indicators for evaluating the disease activity of ankylosing spondylitis

The C-reactive protein to prealbumin ratio (CPR) and fibrinogen to prealbumin ratio (FPR) in serum are two emerging biomarkers. The purpose of this study is to explore the relationship between these two markers and Bath Ankylosing Spondylitis Disease Activity Index (BASDAI) and Ankylosing Spondylitis Disease Activity Scores (ASDAS). A total of 163 patients with AS and 120 healthy examinees were included in this study. The t-test and Mann-Whitney U ranking test were used to analyze the differences between groups. The spearman-test was used to analyze the correlation between erythrocyte sedimentation rate (ESR), c-reactive protein (CRP), fibrinogen (Fib), prealbumin (PAlb), CPR, FPR, and AS disease activity in the test group. We generated the receiver operating characteristic curves (ROC) of CPR and FPR and determined the discriminating ability by calculating the area under the curve (AUC). Compared with the healthy group, ESR ( p < 0.001), CRP ( p < 0.001), Fib ( p < 0.001), CPR ( p < 0.001), and FPR ( p < 0.001) of AS patients were significantly increased, while PAlb was significantly reduced. CPR and FPR were more correlated to ASDAS-CRP. CPR was positively correlated with CRP, ESR, BASDAI, and ASDAS-CRP in AS patients ( r = 0.959, p < 0.001, r = 0.717, p < 0.001, r = 0.704, p < 0.001, r = 0.763, p < 0.001). FPR was positively correlated with CRP, ESR BASDAI, and ASDAS-CRP in AS patients ( r = 0.779, p < 0.001, r = 0709, p < 0.001, r = 0.551, p < 0.001, r = 0.763, p < 0.001). ROC showed that the AUC levels of CPR and FPR were high (AUC = 0.952 and AUC = 0.893). CPR and FPR are two promising new biological indicators for assessing disease activity in AS patients.

Association between C-reactive protein gene variant and treatment efficacy of etanercept in ankylosing spondylitis patients receiving hip arthroplasty

BACKGROUND

C-reactive protein (CRP) level is one of the most widely used parameters to assess ankylosing spondylitis (AS), since CRP is associated with poor radiographic progression of AS patients. Recent studies have investigated the association between CRP gene variants and AS risk, but with conflicting findings.

MATERIAL AND METHODS

We enrolled 232 AS cases and 314 controls in this case-control study. Next, we assessed the association of CRP gene rs3091244 polymorphism with the efficacy of etanercept for AS. Genotyping was done using a custom-by-design 48-Plex SNP scanTM Kit.

RESULTS

CRP gene rs3091244 polymorphism was associated with an increased risk of AS in this Chinese population. Clinical indicators of AS patients including morning stiffness time, Bath AS function index (BASFI), Bath Ankylosing Spondylitis Disease Activity Index (BASDAI), Visual Analogue Scale (VAS), erythrocyte sedimentation rate (ESR), and CRP were significantly decreased after 12 weeks of etanercept treatment. Furthermore, AA genotype carriers showed higher values of VAS, BASDAI, BASFI, and CRP before etanercept treatment. AA genotype or A allele of rs3091244 polymorphism was associated with Ankylosing Spondylitis Assessment Study group response criteria 20 scores (ASAS20) and Assessment in SpondyloArthritis international Society 40 response (ASAS40) improvement. In addition, AA genotype carriers showed significantly higher CRP levels compared with genotype GG carriers (16.3 vs 8.8 mg/L).

CONCLUSION

CRP gene rs3091244 polymorphism is associated with an increased risk of AS. Additionally, rs3091244 polymorphism could serve as a biomarker for good response to etanercept treatment in AS.