Rheumatologic Perspectives on Sarcoidosis: Predicting Sarcoidosis-Associated Arthritis Through Comprehensive Clinical and Laboratory Assessment.

The primary aim of our study was to evaluate the demographic, clinical, and laboratory characteristics of sarcoidosis patients with musculoskeletal symptoms; investigate the relationship between arthritis development and various laboratory parameters (such as vitamin D, liver enzymes, and ACE levels); and compare the sarcoidosis-associated arthritis cases with those without. We also explored the factors influencing arthritis development and the role of biopsy in diagnosing sarcoidosis within rheumatology practice. This retrospective study analyzed 147 sarcoidosis patients from 2000 to 2024, categorized by the presence ( = 45) or absence ( = 102) of arthritis. Demographic, clinical, and laboratory data, including biopsy results, were collected and compared. The mean age was 56.02 ± 11.21 years, with a mean disease duration of 134.33 ± 56.98 months. Females constituted 86.4% of the cohort. All of the patients presented musculoskeletal involvement. Pulmonary involvement was present in 93.7% of cases, and extrapulmonary involvement included the skin (21.20%), the eyes (14.30%), and peripheral lymphadenopathy (10.6%). Methotrexate was the most common treatment after corticosteroids. In the arthritis group, diabetes mellitus was more frequent ( = 0.024), the GGT levels were higher ( = 0.044), and the 25-hydroxyvitamin D levels ( = 0.002) and the DLCO Adj ( = 0.039) were lower. Multivariable regression showed diabetes mellitus ( = 0.028, OR: 4.805, 95% CI: 1.025-22.518) and low 25-hydroxyvitamin D levels ( = 0.034, OR: 0.914, 95% CI: 0.841-0.993) as factors influencing arthritis development. The other parameters showed no significant differences. This study identified significant clinical, demographic, and laboratory differences between sarcoidosis patients with and without arthritis. The patients with sarcoidosis-associated arthritis exhibited a higher frequency of diabetes mellitus, lower levels of 25-hydroxyvitamin D, and elevated GGT levels. Additionally, the lower DLCO values in the patients with arthritis indicate a more severe impact on pulmonary function, underscoring the importance of comprehensive pulmonary evaluation in this subgroup.