Prevalence and characteristics of inflammatory rheumatic diseases in patients with thalassemia.

Reports of inflammatory rheumatic diseases (IRD) in thalassemia are limited. This study aimed to determine the prevalence and clinical characteristics of IRD in patients with thalassemia disease. Consecutive adult patients with thalassemia disease, confirmed by hemoglobin typing, attending the Hematology Clinic between June 2019 and May 2021 were invited to join this study. All of them had their history taken and a physical examination for IRD. Those with IRD had their medical records reviewed. Sixty-three patients (transfusion-dependent in 50) were included in this study. There was α-, β-, and co-inheritance of α- and β-thalassemia in 22.22%, 73.02%, and 4.76% of the patients, respectively, with β-thalassemia/Hb E disease in 53.97%. Twenty-three patients had IRD (rheumatoid arthritis in 9, gout in 6, systemic lupus erythematosus in 3, spondyloarthropathy in 2, and one patient each with dermatomyositis, overlap syndrome, and unclassified polyarthralgia). Clinical manifestations and laboratory findings were similar to IRD patients in general. In 40 patients without IRD, direct and indirect Coombs tests and antinuclear antibody (ANA) were positive in 51.72%, 27.59%, and 10.26%, respectively. When comparing among these 40 patients, between those with non-transfusion-dependent thalassemia (n = 10) and those with transfusion-dependent thalassemia (n = 30), the latter had non-significantly more positive direct Coombs (60.87% vs. 16.67%), indirect Coombs (30.43% vs. 16.67%), and ANA tests (13.33% vs. 0%). The prevalence of IRD in patients with thalassemia disease was rather high. Positive direct Coombs test and ANA were common in transfusion-dependent patients.