Serum amyloid A as indicating inflammation in Romatoid arthritis, Ankylosis spondylitis and Psoriatic arthritis

We aimed to show that serum amyolid A (SAA) can be used as an indicator of inflammation in rheumatoid Arthritis (RA) , ankylosing spondylitis (AS) and psoriatic Arthritis (PsA), and can be used to evaluate disease activity and treatment response. Our study was performed retrospectively on all patients with RA, AS, and PsA who had measured SAA levels between 2014-2019 followed by the Rheumatology Clinic of our hospital, including other predictive factors. Patient data were obtained from hospital automation and patient files. Age, gender, erythrocyte sedimentation rate (ESR), c-reactive protein (CRP), SAA level (0 months, 3 months and 6 months), RA severity (DAS 28), AS severity and treatment groups were evaluated. In our study, 59.9% patients were RA,36.8% were AS and 3.3% were PsA. The median age of patients with RA was significantly higher than the AS group (p <0.05). The median age of patients with PsA was similar to RA and AS (p> 0.05). The incidence of female patients in RA group was significantly higher than that of women in AS and PsA groups (p <0.05). The ESR median of the RA group was significantly higher than the patients with AS and PsA (p <0.05). ESR values of patients with AS and PsA were not different (p> 0.05). The median CRP was significantly higher in patients with RA than in the AS group (p <0.05). The median CRP level of the PsA group was similar to that of the RA and AS groups (p> 0.05). SAA levels of RA group at 0, 3 and 6 months; It was significantly higher than AS and PsA groups (p <0.05). There was no significant relationship between levels of SAA in AS and PsA groups at 0, 3 and 6 months (p> 0.05). SSA levels of the whole group decreased significantly over time (p <0.05). SAA reductions of the whole group between 0 and 3 months, between 3 and 6 months, and between 0 and 6 months were statistically significant (p <0.05). SAA levels of RA and AS groups were found to decrease significantly over time (p <0.05). SAA reductions of RA and AS groups between 0 and 3 months, between 3 and 6 months, and between 0 and 6 months were statistically significant (p <0.05). The change in SAA levels of the PsA group over time was not statistically significant (p> 0.05). SAA levels of biological and antirheumatic treatment groups decreased significantly over time (p <0.05). SAA reductions between 0 and 3 months, between 3 and 6 months, and between 0 and 6 months were statistically significant in the groups receiving biological and antirheumatic treatment (p <0.05). There was a positive correlation between ESR and CRP levels of serum amiolid levels at 0, 3 and 6 months (p <0.05). Patients with high RA severity were compared with patients with low RA severity. In the ROC curve, the area under the curve of the ESR was larger and superior to CRP and SAA. When the factors affecting RA severity were examined, it was found that ESR was effective alone, but superior to CRP and SAA0. Patients with high AS severity were found to have greater area of CRP under the curve, followed by SAA0 and ESR in the ROC curve compared to those with low AS severity. ESR, CRP and SAA parameters were not found to be effective on AS severity, and CRA was the most powerful factor, followed by SAA. In conclusion, ESR, CRP and SAA are the parameters that can be used in the diagnosis and follow-up of rheumatologic diseases. In addition, ESR was superior in patients with RA, while SAA was superior in AS. Key words: Rheumatoid Arthritis , ankylosing spondylitis, psoriatic Arthritis, serum amiloid A, erythrocyte sedimentation rate, c-reactive protein