Background: Inflammatory changes in rheumatological diseases encompass alterations in shape, number, and size of peripheral blood cells. Complete blood cell parameters may be used as an index of inflammation and disease activity.
Aim of the work: Assess the hematological parameters in rheumatoid arthritis (RA) and identify their relationship with disease activity. Methods: 141 patients with rheumatoid arthritis and 100 healthy controls were included in this study. Full medical history, general and musculoskeletal examination, assessment of disease activity using the DAS 28 score, markers of inflammation, rheumatoid factor (RF) titer, anti-cyclic citrullinated peptide (anti-CCP) titer and complete blood picture were done. Results: RA patients had lower RBCs, Hb, MPV, PWD and Hb/RDW% ratio and higher RDW% than controls. Active RA patients had higher WBCs, neutrophils, and NLR. WBCs and neutrophils were positively correlated with DAS score and CRP titre. NLR ratio correlated positively with the DAS score, CRP and Anti CCP titres. Active RA had higher RDW% and lower HCT, Hb, Hb/PLT, RDW%/PLT, Hb/RDW% ratios. RDW% was positively correlated with DAS score, ESR, CRP, RF and Anti CCP titres. The RDW% differentiated active and inactive RA with best cut-off value >12. Active patients had higher platelets and PLR, which were positively correlated with DAS score . Conclusion: Changes in haematological parameters are significantly associated with disease activity in RA patients and they correlate positively with inflammatory markers. RDW%, platelets count and PLR are the most affected hematologic parameters in relation to DAS score and parameters of disease activity.