Thermal Analysis in the Diagnostics of Inflammatory and Septic Conditions

Background/Objectives: Differentiating between inflammatory and septic purulent processes in the human body remains difficult today. A number of research techniques have emerged recently, and calorimetric investigations have shown promise in the study of malignancies and inflammatory and septic diseases. The purpose of our review article is to present and summarize the potential applications of calorimetric measurements in the study of human inflammatory and septic disorders. Methods: For calorimetric measurements, a small volume of liquid (blood plasma, synovial fluid) or tissue sample is sufficient. The thermal data and denaturation curve obtained during the calorimetric procedure performed by a differential scanning calorimeter (DSC) show the structural changes in the proteins of the examined sample. The thermograms and the calculated thermal values (∆Hcal, calorimetric enthalpy, Tm melting or denaturation temperature) can demonstrate the unique variation and characteristics of the studied pathologies. These calorimetric procedures have recently been referred to as thermal liquid biopsy (TLB). Results: With the help of proliferation thermograms provided by isothermal calorimetric measurements (IMCs), it is also possible to detect bacteria present in low concentrations in different samples. Based on the literature and on our workgroup’s data, calorimetric analyses have been successfully applied in the differential diagnosis of numerous human inflammatory diseases (psoriasis, systemic lupus erythematosus, synovitis) and septic conditions (septic arthritis, periprosthetic joint infection, fracture related joint infection). Conclusions: Considering the advantages of the technique, calorimetric analyses could serve as a complementary method in the clinical diagnostics of septic conditions in the future.