A rapid matrix metalloproteinase-8 bedside test for the detection of intraamniotic inflammation in women with preterm premature rupture of membranes

Abstract

Objective: To examine whether the MMP-8 PTD Check (SK Pharma Co, Ltd, Kyunggi-do, Korea), a rapid bedside test that can be performed in 15 minutes, is of value in the identification of intraamniotic infection and/or inflammation and in the assessment of the likelihood of adverse pregnancy outcome in patients with preterm premature rupture of membranes (PPROM).

Study design: Amniotic fluid was retrieved by transabdominal amniocentesis in 141 women with PPROM (<35 weeks' gestation). Fluid was cultured for aerobic and anaerobic bacteria and genital mycoplasmas; the remaining amniotic fluid was stored. The stored amniotic fluid was analyzed for interleukin-6 and MMP-8 PTD Check test. Intraamniotic infection/inflammation was defined as a positive amniotic fluid culture and/or elevated amniotic fluid interleukin-6 concentration (>2.6 ng/mL). Nonparametric and survival analysis were used.

Results: The prevalence of intraamniotic infection/inflammation was 43% (60/141 women) and that of proven amniotic fluid infection was 18% (25/141 women). Patients with a positive MMP-8 PTD Check test result had a significantly higher rate of intraamniotic infection/inflammation (77% [54/70 women] vs 9% [6/71 women]; P < .001); proven amniotic fluid infection (33% [23/70 women] vs 3% [2/71 women]; P < .001), and adverse outcome than those with a negative MMP-8 PTD Check test result. Adverse outcome included shorter interval to delivery and higher rate of preterm delivery, histologic chorioamnionitis, funisitis, low Apgar scores, and significant neonatal morbidity. A positive MMP-8 PTD Check test result had a sensitivity of 90%, a specificity of 80%, a positive predictive value of 77%, and a negative predictive value of 92% in the identification of intraamniotic infection/inflammation, and was an independent predictor of interval to delivery (hazards ratio, 3.7; 95% CI, 2.4-5.9) and significant neonatal morbidity (odds ratio, 3.1; 95% CI, 1.2-7.9).

Conclusion: The MMP-8 PTD Check test is a rapid, simple, and sensitive bedside test to detect intraamniotic infection/inflammation and to predict adverse outcome that includes short latency, chorioamnionitis, and significant neonatal morbidity in patients with PPROM. The results of this study bring the rapid detection of intraamniotic infection/inflammation to the bedside in clinical obstetrics.