Significantly increased concentration of soluble urokinase-type plasminogen activator receptor in the blood of patients with pelvic inflammatory disease

Background: To determine expression levels of urokinase-type plasminogen activator (uPA), soluble urokinase-type plasminogen activator receptor (suPAR), plasminogen activator inhibitor-1 (PAI-1) in plasma and to identify gene polymorphisms specific to patients with pelvic inflammatory disease (PID) and healthy controls. Methods: Enzyme-linked immunosorbent assay and polymerase chain reaction-restriction fragment length polymorphism were used to measure plasma levels and polymorphisms in uPA, suPAR, and PAI-1 among seventy healthy controls and 64 PID patients before and after they received routine treatment protocols. Results: The levels of plasma uPA (ng/ml) and soluble suPAR (pg/ml) were significantly increased in PID patients (uPA: 0.57 ± 0.03; suPAR: 1372.04 ± 68.20) when compared to that in normal controls (uPA: 0.55 ± 0.06, p = 0.002; suPAR: 1192.46 ± 51.98, p = 0.04); moreover, suPAR decreased significantly after treatment when compared to levels noted in the same patients (1220.06 ± 58.14; p = 0.003) after they received treatment. The increased expression of suPAR was significantly correlated with WBC counts (r = 0.382, p = 0.002, n = 64) in blood as well as the plasma levels of CRP (r = 0.441, p. <0.0001, n = 64) and uPA (r = 0.426, p. <0.0001, n = 64) of PID patients prior to receiving treatment. Conclusions: Increased plasma suPAR could be a biological marker for the diagnosis of PID and may reflect a new focus in targeted therapy for pelvic inflammatory disease.