Significant elevation of plasma matrix metalloproteinase-9 level and its ratio to matrix metalloproteinase-2 in patients with pelvic inflammatory disease

ObjectiveTo detect the expression of plasma matrix metalloproteinase-2 (MMP-2) and MMP-9, and MMP-9:MMP-2 ratio in patients with pelvic inflammatory disease (PID).DesignA consecutive study with approximate 1:2 case-to-control ratio.SettingUniversity hospital.Patient(s)Forty-seven patients with PID and 80 healthy women.Intervention(s)Collected blood specimens of patients with PID before and after treatment.Main Outcome Measure(s)ELISA and gelatin zymography were used to measure the expression of plasma MMP-2 and MMP-9.Result(s)The level of plasma MMP-9 or MMP-9:MMP-2 ratio was elevated in patients with PID compared with healthy controls and decreased significantly after treatment. The activity of MMP-9, but not MMP-2, tended to be higher in 47 patients with PID before the treatment compared with that after the treatment. Pretreatment plasma MMP-9 or MMP-9:MMP-2 ratio was significantly correlated with white blood cell (WBC) and neutrophil counts. As prediction markers for PID, the sensitivities of MMP-9 and MMP-9:MMP-2 ratio were 76.6% and 76.6%, whereas the negative predictive values were 82.5% and 83.3%.Conclusion(s)Level of plasma MMP-9 and MMP-9:MMP-2 ratio may act as prediction markers for PID. In patients with PID, 80% have a plasma MMP-9 level higher than 115 ng/mL or a MMP-9:MMP-2 ratio higher than 2.15.