Background: Rheumatic diseases are one of the most common problems in modern societies. The majority of rheumatic diseases occur when the human immune system attacks its own tissues, including the joints. Therefore, the aim of this study was to investigate the effect of sex, age, and drugs on element levels in synovial fluids originating from patients with arthritis and rheumatic diseases.
Methods: This study was based on a flame atomic absorption (FAAS) and emission spectroscopic analysis (AES) of the concentration of selected essential elements, including both microelements (iron, zinc, copper, and manganese) and macro elements (calcium, magnesium, sodium, and potassium) and their interpretation by statistical methods.
Results: The concentrations of essential elements in synovial fluids showed the following order: Mn > Fe > Zn > Cu for microelements, and Na > Mg > Ca > K for macro elements. It was also revealed that in the case of arthritis (rheumatic disease) several elements, such as Fe, Zn, K, Mg, and Ca were accumulated in the synovial fluid. The linear correlation coefficients indicated statistically significant relationships among elements in the investigated samples, such as Fe and Zn, and Ca and Mg. A negative correlation was found between Zn and Na.
Conclusions: The chemical profiling of synovial fluids of patients with rheumatic diseases based on the identification of essential elements and applying principal component analysis (PCA), allowed us to identify that the levels of Fe, Zn, Ca, Mg, and K have the highest impact on the differentiation of synovial fluid samples. No significant differences in element levels by sex or age were observed. The drug effect was especially significant for Zn, Cu, Na, and K, where differences in these element levels were noticed.
Arthritis, Rheumatic disease, Synovial fluids, Micro- and macro elements