G. Rizzo et al., THE DIAGNOSTIC-VALUE OF INTERLEUKIN-8 AND FETAL FIBRONECTIN CONCENTRATIONS IN CERVICAL SECRETIONS IN PATIENTS WITH PRETERM LABOR AND INTACTMEMBRANES, Journal of perinatal medicine, 25(6), 1997, pp. 461-468
The objectives of this study were 1) to evaluate interleukin-8 concent
rations in cervical secretions in predicting preterm delivery, microbi
al invasion of the amniotic cavity and histologic chorioamnionitis in
patients with preterm labor and intact membranes and 2) to compare the
diagnostic value of interleukin-8 with fetal fibronectin determinatio
ns in predicting preterm delivery, microbial invasion of the amniotic
cavity and histologic chorioamnionitis in patients with preterm labor
and intact membranes. Interleukin-8 and fetal fibronectin were assayed
in cervical secretions in 106 patients with singleton pregnancies and
intact membranes admitted for preterm labor. Amniotic fluid obtained
by amniocentesis was cultured and placentas (No = 43) analyzed for the
presence of chorioamnionitis. The prevalence of pregnancies delivered
preterm was 46.2% (49/106) and 15.09% (16/106) of amniotic fluid cult
ures were positive. Interleukin-8 levels in cervical secretions were s
ignificantly increased in patients who delivered preterm (p less than
or equal to 0.0001), in presence of positive amniotic fluid culture (p
= 0.0016) and histological chorioamnionitis (p = 0.008) than in patie
nts with negative findings. Receiver-operator characteristics curve an
alysis showed that an interleukin-8 value > 450 pg/ml is comparable to
that of a fetal fibronectin value > 50 ng/ml in predicting preterm de
livery (p = 0.247). Among patients who delivered preterm interleukin-8
concentrations > 860 pg/ml predicted a positive amniotic fluid cultur
e with a sensitivity of 81.2% and a specificity 66.6%. Further, in pat
ients who delivered preterm and had a negative amniotic fluid culture,
IL-8 concentrations > 480 pg/ml predicted histological chorioamnionit
is with a sensitivity 78.5% and specificity 61.5%. A positive fetal fi
bronectin > 50 ng/ml was not predictive of either a positive amniotic
fluid culture or the presence of histological chorioamnionitis. In con
clusion, increased concentrations of interleukin-8 and fetal fibronect
in are associated with impending delivery and their diagnostic value s
eems comparable. However, interleukin-8 concentrations identify patien
ts at risk of a positive amniotic fluid culture and the presence of hi
stological chorioamnionitis. Measurement of interleukin-8 in cervical
secretion is a non-invasive method to identify patients at risk for bo
th preterm delivery and intrauterine infection.