Evaluation of inflammatory indices at diagnosis in adult still's disease for differential diagnosis and disease prognosis

Adult Onset Still's Disease (AOSD) is characterized by laboratory abnormalities commonly associated with systemic inflammation, such as neutrophilic leukocytosis and lymphopenia. However, sufficient studies using indices that could associate blood cells with inflammation have not been conducted. In this study, we aimed to compare clinical markers and inflammatory indices at the time of diagnosis in patients with AOSD and those with fever of unknown origin in terms of diagnosis and prognosis outcomes. The patient files reviewed totaled 4300 and 320 patients meeting the inclusion criteria were enrolled in the study. The gender distribution was 150 (47%) female and 170 (53%) male. Methodologically, the study was divided into two groups: 231 (72.2%) cases with Fever Of Unknown Origin (FUO) and 89 (27.8%) cases of AOSD. A higher proportion of males was found in the FUO group, whereas a higher proportion of females was noted in the AOSD group (p=0.001). The average age of the FUO group was older compared to the AOSD group (p=0.001). Significant statistical differences between the groups were observed in inflammation markers such as AF score, AISI, LMR, and dNLR (p<0.05), and laboratory parameters like WBC, neutrophils, lymphocytes, ALT, creatinine, ferritin, and CK (p<0.05). Statistically significant differences were also found in musculoskeletal system involvement (p=0.001), pulmonary involvement (p=0.005), LAP (p=0.023), fever (p=0.001), sore throat (p=0.001), and rash (p=0.001). Significant differences in serological tests such as IGM (p=0.010), IGG (p=0.044), and tumor marker variables (p=0.001) were also identified between the groups. A total of 27 cases of relapse were observed, all of which were within the AOSD group. Our study's findings are generally in line with the literature, although some discrepancies have been noted. Our research emphasizes the potential importance of symptoms and biological markers indicative of inflammation in AOSD and FUO patients for guiding diagnosis and treatment. Further comprehensive studies could allow for a deeper understanding of these diseases and the development of more effective treatment methods.