Maternal serum cytokines concentrations during normal pregnancy and labor

OBJECTIVES: The purpose of our study was to determine maternal serum concentrations of IL-8, IL-6, IFN-gamma during normal pregnancy and labor. MATERIALS AND METHODS: Maternal serum IL-8, IL-6 and IFN-gamma levels were measured by means of ELISA technique in 41 healthy pregnant women in 22-42 week gestation and 15 healthy women in labor at term. All newborns and afterbirths had no signs of infection. RESULTS: IL-8 values for pregnant women ranged from 1.98 to 35.2 pg/ml with the median value 10.24 pg/ml, and the 95th percentile 24.5 pg/ml. IL-8 values for women in labor at term ranged from 3.96 to 54.8 pg/ml with the median 10.4 pg/ml. No statistically significant changes in serum IL-8 concentration were observed during pregnancy or in labor. Serum IL-6 concentrations in pregnant women ranged from 0 to 21.7 pg/ml with the median value 0 pg/ml, and the 95th percentile 15.5 pg/ml. Serum IL-6 concentrations in women in labor at term were significantly higher (p < 0.05): ranged from 0 to 39.2 pg/ml with the median 10.1 pg/ml and 95-th percentile 33.5 pg/ml. Maternal serum IFN-gamma concentrations in pregnant women ranged from 0 to 9.8 pg/ml with the median value 3.9 pg/ml, the 95th percentile 9.2 pg/ml and didn't differ during labor at term: range from 0 to 14.5 pg/ml, median 1.9 pg/ml. CONCLUSIONS: Our data revealed that maternal serum IL-8 concentrations didn't changed during the course of pregnancy and in labor. Women in labor had significantly elevated serum IL-6 concentrations compared to those in pregnancy. We didn't observed such changes in serum IFN-gamma levels.     

Amniotic fluid glucose and cytokines values in the early diagnosis of amniotic infection in patients with preterm labor and intact membranes

Objective: Our goal was to compare sensitivity, specificity, and predictive values of glucose and cytokines [interleukin-1 (IL-1), interleukin-6 (IL-6), interleukin-8 (IL-8), and tumor necrosis factor (TNF)] in amniotic fluid (AF) to detect an AF-positive culture.

Methods: Amniocentesis was performed on 113 patients with preterm labour (PTL) and intact membranes. Fluid was cultured for aerobic and anaerobic bacteria, and for mycoplasmas. AF analysis included cytokines and glucose determinations.

Results: The prevalence of positive AF cultures was 11.5% (13/113). Anaerobic bacteria were isolated in 9 patients (69.2%). The glucose < 16 mg/dl and cytokines values; IL-1 >640 pg/ml, IL-6 >55,000 pg/ml, IL-8 >1,000 pg/ml, TNF >672 pg/ml, were significantly correlated (P< 0.01) with AF culture result. Glucose had a sensitivity of 69.2% and a specifity of 96% for the prediction of positive AF culture. The sensitivity and specifity of the cytokines ranged from 61.5–53.4% and 79.8–8.99%, respectively.

Conclusions: In the diagnosis of the AF-positive culture, glucose > 16 mg/dl is more sensitive than cytokines.     

Relationships Among Cytokines (IL-1, TNF,and IL-8) and Histologic Markers of Acute Ascending Intrauterine Infection

Amniotic fluid levels of interleukin-1β (IL-1β), tumor necrosis factor-α (TNF-α), and interleukin-8 (IL-8) were determined in 13 pregnancies presenting with preterm spontaneous membrane rupture in which there were no clinical indications of intraamniotic infection. These levels were compared to the placental histology. All 8 cases in which elevated cytokine levels were identified also had histologic evidence of both maternal and fetal acute inflammation in choriodecidua and chorionic plate, and umbilical and chorionic vessels, respectively. Cytokine concentrations correlated with the severity of maternal inflammation, but not the severity of fetal inflammation as assessed histologically. Elevated levels of both IL-1β and TNF-α were not uniformly observed in amniotic fluid; all cases with either elevated IL-1β of TNF-α had elevated levels of IL-8. Microbial studies of the 8 patients with histologic acute inflammation showed 5 with positive amniotic fluid cultures and/or gram stains. One had positive gram stain only for gram positive cocci, and the 4 remaining grew mixed vaginal flora (2), Fusobacterium spp. (1), and E. coli (1). One aspect of the functional immaturity of the fetal polymorphonuclear leukocyte may be related to impaired response to IL-8. In addition, the presence of IL-8 may be a clinical indicator of intraamniotic infection.     

Labor and infection. II. Bacterial endotoxin in amniotic fluid and its relationship to the onset of preterm labor

We have previously reported the detection of endotoxin in the amniotic fluid of patients with gram-negative intraamniotic infection. Endotoxin or lipopolysaccharide is a potent biologic product capable of inducing prostaglandin release from several cell types and, therefore, may be involved in the onset of human parturition in the presence of intraamniotic infection. This article describes a technique for the quantification of endotoxin in amniotic fluid. The method uses a computer-assisted quantification of the turbidimetric reaction between the Limulus amebocyte lysate and endotoxin. Serial dilutions of Escherichia coli endotoxin in culture-negative amniotic fluid were prepared, and the samples were run in the assay. Amniotic fluid was found to enhance the reaction, and a dilution of 1:20 was required for this biologic fluid to behave similarly to pyrogen-free water. The sensitivity of this kinetic turbidimetric technique in the detection of endotoxin in amniotic fluid was 40 pg/ml. This method was applied to the quantification of endotoxin concentration in amniotic fluid in 26 patients with intraamniotic infection and premature rupture of membranes. Patients in active labor had higher concentrations of endotoxin (median = 47,514 pg/ml) than nonlaboring patients (median = 635 pg/ml) (p less than 0.025). Therefore, women with preterm labor had a higher median concentration of endotoxin in amniotic fluid than patients who were not in labor.     

Amniotic fluid interleukin-18 at mid-trimester genetic amniocentesis: relationship to intraamniotic microbial invasion and preterm delivery

Objective  To determine the value of amniotic fluid interleukin-18 (AF IL-18) in the diagnosis of microbial invasion of the amniotic cavity and prediction of preterm delivery (PTD).
Design  Analysis of the results of AF collected prospectively following genetic amniocentesis between February 2006 and September 2007.
Setting  A tertiary referral centre for fetal medicine.
Methods  Following amniocentesis, a sample of amniotic fluid was transferred to the laboratory for aerobic and anaerobic bacterial cultures, Ureaplasma urealyticum culture and IL-18 assays. All women who delivered preterm (<37 weeks of gestation) formed the study group. The control group consisted of the two subsequent women who also underwent amniocentesis during the same time period and delivered a normal neonate at term, matched for maternal age, parity and indication for amniocentesis.
Main outcome measures  The relationship between AF IL-18 levels and the risk of both microbial invasion of the amniotic cavity and PTD.
Results  Forty-eight women who delivered preterm (<37 weeks) were matched with 96 controls. The preterm delivery group had significantly higher concentrations of IL-18 (median = 609 pg/ml, interquartile range: 445.7–782.7) compared to controls (median = 322.1 pg/ml, interquartile range: 277.7–414.4), ( P  < 0.001). IL-18 level was also significantly higher ( P  < 0.001) in cases with positive amniotic fluid cultures (median = 697.7, interquartile range: 609.0–847.2) compared to those with negative ones (median = 330.9 pg/ml, interquartile range: 235.2–440.8).
Conclusions  Elevated mid-trimester concentrations of AF IL-18 can identify women at risk for intraamniotic infection and spontaneous PTD.     

Amniotic fluid prostaglandin F2 increases even in sterile amniotic fluid and is an independent predictor of impending delivery in preterm premature rupture of membranes

Objective.?To determine whether amniotic fluid (AF) concentration of prostaglandins (PGs) increases in patients with intra-amniotic inflammation and/or proven AF infection in preterm PROM, and can predict impending delivery.

Methods.?AF PGF2a concentrations were determined by ELISA in 140 singleton pregnancies with preterm premature rupture of membranes (PROM) (≤35 weeks). AF was cultured for aerobic and anaerobic bacteria, and genital mycoplasmas. Intra-amniotic inflammation was defined as an elevated AF matrix metalloproteinase-8 concentration (>23 ng/ml).

Results.?(1) Patients with intra-amniotic inflammation and a negative AF culture had a significantly higher median AF PGF2a than those without intra-amniotic inflammation and with a negative culture (p < 0.001); (2) However, there was no difference in the median AF PGF2a between patients with intra-amniotic inflammation with a negative culture and those with culture-proven AF infection (p > 0.1); (3) Patients with an elevated AF PGF2a had a significantly shorter interval-to-delivery than those with a low AF PGF2a (≤170 pg/mL) (p < 0.001); (4) An elevated AF PGF2a (≤170 pg/mL) concentration was a significant predictor of the duration of pregnancy after adjusting for gestational age and AF inflammation/infection (p < 0.005).

Conclusions.?AF PGF2a (≥170 pg/mL) concentration increased in patients with intra-amniotic inflammation regardless of AF culture results. Moreover, an elevated AF PGF2a concentration was an independent predictor of impending delivery in preterm PROM.     

Amniotic fluid interleukin-6 and tumor necrosis factor-α at mid-trimester genetic amniocentesis: Relationship to intra-amniotic microbial invasion and preterm delivery

Objective

To determine the value of amniotic fluid interleukin-6 (AF IL-6) and tumor necrosis factor-α (AF TNF-α) in the diagnosis of microbial invasion of the amniotic cavity and in the prediction of preterm delivery (PTD).

Study design

Following amniocentesis, a sample of amniotic fluid was sent for aerobic and anaerobic bacterial cultures along with Ureaplasma urealyticum culture and it was also assessed for IL-6 and TNF-α.

Results

Forty-eight women who delivered preterm (<37 weeks) were matched with 96 controls. The AF IL-6 and TNF-α concentrations of women with spontaneous PTD were significantly higher than those who delivered at term (IL-6: 176.3 pg/ml [130.6–208.6] vs. 52.3 pg/ml [37.2–92.3]; TNF-α: 8.8 pg/ml [7.2–10.7] vs. 5.5 pg/ml [5.0–6.3]). AF IL-6 and TNF-α concentrations of >99.3 pg/ml and of >6.6 pg/ml respectively, had a sensitivity of 89.6% and 81.3% and a specificity of 80.3% and 79.2% for the prediction of spontaneous PTD. Moreover, AF IL-6 and TNF-α concentrations of >99.3 pg/ml and of 6.3 pg/ml respectively, had a sensitivity of 91.9% and 78.4% and a specificity of 73.8% and 70.1% for the prediction of a positive AF culture.

Conclusions

Elevated mid-trimester concentrations of AF IL-6, or/and of TNF-α can identify women at risk for intra-amniotic infection and for spontaneous PTD.     

滴虫性阴道炎阴道局部细胞因子IL-2、IL-8、IL-13的变化

目的:检测滴虫性阴道炎(trichomanasvaginitis,TV)患者阴道局部细胞因子白介素-2(interleukine-2,IL-2)、白介素-8(interleukine-8,IL-8)及白介素-13(interleukine-13,IL-13)的变化,探讨它们在疾病及机体免疫防御机制中的作用。方法:选取生育年龄女性滴虫性阴道炎患者40例(TV组)为研究组,同期选取健康体检无阴道炎症的健康育龄女性66例为对照组,用ELISA法检测这2组人群中阴道局部IL-2、IL-8、IL-13及免疫球蛋白E(immunoglobinE,IgE)的水平。结果:(1)与健康对照组阴道局部IL-2(7.24pg/ml)、IL-8(1796.99pg/ml)、IL-13(22.54pg/ml)水平相比,滴虫性阴道炎患者阴道局部的IL-2为8.80pg/ml,有升高趋势(P=0.11);IL-8为7119.00pg/ml,IL-13为36.43pg/ml,均显著升高(P(0.001,P(0.001);(2)滴虫性阴道炎患者阴道局部IL-2/IL-13显著下降(P(0.001);(3)与健康对照组IgE水平(0.89IU/ml)相比,滴虫性阴道炎组(1.05IU/ml)显著升高(P=0.008)。结论:(1)滴虫性阴道炎时阴道局部IL-2有升高趋势,IL-13及IgE升高,提示阴道局部细胞免疫及体液免疫在抗滴虫感染中均起作用;(2)滴虫性阴道炎时阴道局部IL-8升高提示阴道局部粘膜的先天免疫应答在抗滴虫感染中起重要作用;(3)IL-2/IL-13下降提示可能出现了Th1/Th2细胞的免疫功能失衡。     

Maternal serum cytokines in labor, pregnancy and chorioamnionitis

The purpose of our study was to compare maternal serum levels of interleukin-6, interleukin-8, tumor necrosis factor-alpha and interferon-gamma in gravidities, during spontaneous term and preterm labor and their relation to histologic chorioamnionitis. METHODS: We investigated 61 women: 10 in preterm labor, 36 in term labor and 15 healthy pregnant nonlabouring controls. Venous bloods for cytokines determinations were obtained during the first stage of labor and during routine screening tests. Titers of cytokines were measured by means of ELISA technique. All births after preterm deliveries were examined to establish histologic chorioamnionitis. RESULTS: Serum levels of IL-6 and IL-8 were significantly elevated both in term (mean: IL-6: 17.5 +/- 58 pg/ml; IL-8: 148 +/- 215 pg/ml) and preterm labor (IL-6: 23 +/- 44 pg/ml; IL-8: 332 +/- 389 pg/ml) when compared to nonlabouring gravidities (IL-6: 5 +/- 7 pg/ml; IL-8: 14 +/- 11 pg/ml). IL-6 and IL-8 titers were statistically similar in term and preterm labors and in patients with and without histologic chorioamnionitis. TNF-alpha and IFN-gamma were not statistically analyzed because only a few patients had detectable serum levels of these cytokines. CONCLUSION: Serum levels of IL-6 and IL-8 in both: term and preterm labor are elevated in comparison to nonlabouring gravidities. The elevated levels of these cytokines are not connected with coexisting chorioamnionitis.     

Maternal serum cytokine levels in pregnancies complicated by PROM

OBJECTIVE: The aim of the study was to evaluate the maternal serum cytokines levels in pregnancies complicated by premature rupture of membranes (PROM). MATERIALS AND METHODS: Maternal serum of IL-1 beta, IL-4, IL-6, IL-8 and TNF-alfa levels were assessed in patients with PROM between 24-34 weeks of pregnancy (n = 45). Control group consisted of healthy pregnant women (n = 41) at 24-34 weeks of gestation. Serum cytokines concentrations were measured by commercial available enzyme-linked immunosorbent assays. C-reactive protein level and WBC were estimated in both groups. RESULTS: Compared to healthy pregnant, the group of patients with PROM had significantly higher serum levels of IL-1 beta (0.76 pg/ml vs 0.41 pg/ml, p = 0.022), TNF-alfa (1332.46 pg/ml vs 58.01 pg/ml, p < 0.00001) and IL-8 (15.79 pg/ml vs 0 pg/ml, p < 0.00001). CRP concentration and WBC were also significantly higher in serum of pregnant women with PROM then in healthy ones (CRP: 10 mg/l vs 0 mg/l, p = 0.043; WBC: 13,188 +/- 3625/mm3 vs 9132 +/- 1913/mm3, p < 0.00001). No significant differences in IL-6 and IL-4 levels were found between groups. CONCLUSION: Differences in serum maternal levels of cytokines between patients with premature ruptures of membranes and healthy pregnant women suggest that reasons and/or consequences of PROM results in changes in immunological system.     

Amniotic-fluid Lactoferrin: A Marker for Subclinical Intraamniotic Infection Prior to 32 Weeks Gestation

Objective: Lactoferrin is a glycoprotein released from the secondary granules of activated neutrophils in the setting of infection. The purpose of this study was to determine if amniotic-fluid (AF) lactoferrin levels are elevated in preterm labor (PTL) patients with subclinical intraamniotic infection (IAI).Methods: AF samples were obtained from 186 pregnant patients with the following characteristics: group 1 - term, no labor; group 2 - preterm, no labor; group 3 - PTL with IAI; group 4 - PTL without IAI. Lactoferrin levels were measured with an enzyme-linked immunosorbent assay (ELISA).Results: AF lactoferrin levels were elevated in normal gestation after 31 weeks (P < 0.0001). Lactoferrin levels were also higher in infected PTL patients compared with noninfected PTL patients at gestations 2.5 mug/ml is highly suggestive of infection in PTL patients at <32 weeks, with an overall sensitivity of 82% and a specificity of 83%, when infection is defined as a positive AF culture or positive placental histology.Conclusions: AF lactoferrin levels increase after 31 weeks in normal gestations, but lactoferrin levels >2.5 mug/ml in PTL patients before this gestational age are highly suggestive of IAI. AF lactoferrin levels may be a useful clinical tool for selecting those PTL patients who might benefit from antimicrobial therapy, closer observation, or early delivery.     

The relationship between the levels of proinflammatory cytokines, and AFI value in pregnancies complicated by premature rupture of membranes

OBJECTIVE: The aim of the study was to test the relationship between maternal serum proinflammatory cytokines level and AFI (amniotic fluid index) in pregnancies complicated by premature rupture of membranes (PROM). MATERIALS AND METHODS: The maternal serum levels of IL-6, IL-1 beta and TNF-alfa were assessed in patients with PROM between 24-34 weeks of gestation (n = 45) by means of commercially available ELISA assays. The patients were divided in two groups according to AFI values: < 50 (n = 25) mm and < or = 50 mm (n = 20). Cytokine concentrations were compared between groups. RESULTS: The median concentrations of proinflammatory cytokines in maternal serum were: IL-6--5.74 pg/ml (range 3.24-3111 pg/ml), IL-1 beta--0.76 pg/ml (range 0.001-3.16 pg/ml), TNF-alfa--1332.46 pg/ml (range 2.13-1969.68 pg/ml). Compared to patients with AFI values > or = 50 mm, the group of patients with AFI < 50 mm had significantly higher concentration of IL-6 (6.61 pg/ml vs. 4.66 pg/ml; p = 0.002). No significant differences in IL-1 beta and TNF-alfa levels have been found between groups. The significant correlation have been observed between maternal serum level of IL-6 and AFI values (R = -0.47, p = 0.003), but not of IL-1 beta and TNF-alfa. CONCLUSION: The assessment of AFI values in pregnancies complicated by premature rupture of membranes seems to be the valuable method of early diagnosis in cases of intrauterine infection.     

IL-1beta, IL-6 and IL-8 levels in gyneco-obstetric infections

OBJECTIVE: During pregnancy cytokines and inflammatory mediators stimulate the expression of prostaglandin, the levels of which determine the onset of labor. The aim of this work was to study interleukin IL-1beta, IL-6 and IL-8 levels in the vaginal discharge, serum and urine of pregnant women with genitourinary infection before and after specific treatment. One hundred and fifty-one patients were studied during the second or third trimester of their pregnancy. METHODS: The selected patients were: healthy or control group (n = 52), those with bacterial vaginosis (n = 47), those with vaginitis (n = 37), those with asymptomatic urinary infection (n = 15) and post-treatment. The level of cytokines was assayed by ELISA test. The Mann-Whitney U-test was used for statistical analysis. RESULTS: The IL-1beta levels in vaginal discharge were: control 103.5 +/- 24.2 pg/ml, bacterial vaginosis 1030 +/- 59.5, vaginitis 749.14 +/- 66.7l ( p < 0.0001), post-treatment 101.4 +/- 28.7. IL-6 values were similar in both control and infected groups, and there were no patients with chorioamnionitis. In vaginal discharge IL-6: control 14.2 +/- 3.9 pg/ml, bacterial vaginosis 13.2 +/- 3.8, vaginitis 13 +/- 4.2. IL-8 levels were: control 1643 +/- 130.3 pg/ml, bacterial vaginosis 2612.7 +/- 257.7, vaginitis 3437 +/- 460 (p < 0.0001), post-treatment 1693 +/- 126.6. In urine the results were: control 40.2 +/- 17 pg/ml, asymptomatic urinary infection 1200.7 +/- 375 (p < 0.0001). In patients with therapeutic success both IL-1beta and IL-8 returned to normal levels. CONCLUSIONS: Genitourinary infections induce a significant increase in IL-1beta and IL-8 levels in vaginal secretions, and IL-8 in urine as well. Both cytokines could be useful as evolutive markers of infection.     

Increased IL-6 and IL-8 levels in cervicovaginal secretions of patients with cervical cancer.

OBJECTIVE: Conflicting data exist on IL-6 production by human papillomavirus (HPV) immortalized cell lines and several cervical carcinoma cell lines. However, no information has been reported on the levels of cytokines in cervicovaginal washings in relation to cervical neoplasia. The aim of this study was to investigate whether local production of IL-6 could be found and whether the level of this cytokine was related to the severity of cervical neoplasia. IL-8 was measured to obtain additional information on an inflammatory cytokine with possible epithelial origin. METHODS: Cervicovaginal washings and sera were obtained from 35 patients with invasive cervical cancer, 62 patients with cervical intraepithelial neoplasia (CIN), and 25 control subjects. IL-6 and IL-8 levels were determined by ELISA. HPV DNA in cervical smears was detected by a HPV-16-specific PCR method and additionally by CPI/IIG PCR. Histological analysis of the inflammatory infiltrate was performed on hematoxylin-eosin-stained tissue sections. RESULTS: In the patients with cervical cancer, those with CIN, and the controls, the median IL-6 concentration in cervicovaginal washings was 171 pg/ml (interquartile range: 54-780), 22 pg/ml (<2-73), and < 2 pg/ml (<2-<2), respectively. For IL-8, the levels were 2756 pg/ml (1651-7107), 489 pg/ml (248-1158), and 631 pg/ml (346-897), respectively. In most subjects the local levels were much higher than in serum. Local IL-6 and IL-8 levels were significantly higher in patients with cervical carcinoma compared with CIN patients and controls. Likewise, local IL-6 levels were increased in patients with CIN compared with controls. No relation was found between cytokine levels and CIN grade or between cytokine levels and the inflammatory infiltrate scored by histological analysis. CONCLUSIONS: There is local production of IL-6 and IL-8 in cervicovaginal secretions, and the production of IL-6 was related to the severity of cervical neoplasia.     

Evaluation of rapid diagnostic tests in the detection of microbial invasion of the amniotic cavity.

OBJECTIVE: We sought to determine and compare the value of several rapid diagnostic tests in the detection of intraamniotic infection. STUDY DESIGN: Gram stain, intraamniotic glucose level determination, leukocyte esterase assay, and the Limulus amebocyte lysate assay were performed on 144 amniotic fluid specimens retrieved by transabdominal amniocentesis in 136 patients with preterm premature rupture of the membranes or preterm labor. Diagnostic indices for a positive amniotic fluid culture and the development of clinical infection were calculated for each rapid test. Receiver-operator characteristic curves were generated to help select the optimal glucose level and combination of tests to detect intraamniotic infection. RESULTS: The greatest sensitivity for predicting either a positive culture or subsequent clinical infection in preterm labor patients and in predicting clinical infection in patients with preterm premature rupture of the membranes was demonstrated by a low glucose level. The Gram stain provided the greatest positive predictive value in patients with preterm labor. Combining the Gram stain and measurement of intraamniotic glucose levels did not improve sensitivity above glucose alone or positive predictive value above Gram stain alone. CONCLUSION: Leukocyte esterase determination and Limulus amebocyte lysate assay are insensitive indicators of intraamniotic infection. Selection of Gram stain or glucose level measurement alone or in combination as an appropriate screen for intraamniotic infection will depend on the clinicians' false-positive rate threshold.     

High interleukin-16 concentrations in the early second trimester amniotic fluid: an independent predictive marker for preterm birth

Objective: Infection is believed to be one of frequent and important causes of preterm labor. We attempted to evaluate whether the level of inflammatory markers, e.g. interleukin-16 (IL-16), interleukin-18 (IL-18), and ferritin, in amniotic fluid at early second trimester can predict preterm birth. Methods: Amniotic fluid (AF) samples were collected from 350 pregnant women who had trans-abdominal amniocentesis for genetic indications at 16 to 20 weeks of gestation. AF levels of IL-16, IL-18 and ferritin levels were measured by immunoassay and were correlated with pregnancy outcomes. Results: Among the 350 pregnant women, 58 (16.6%) had preterm birth (<37 weeks gestation). AF levels of IL-16, IL-18, and ferritin were significantly higher in pregnant women with subsequent preterm birth. Multivariate analyses showed that a quartile higher of AF IL-16 level was significantly associated with preterm birth (OR: 3.09, 95% CI 1.52–6.27, p = 0.002). A receiver operating characteristic analysis revealed that an IL-16 cutoff value of 105 pg/ml was a reliable predictor of preterm birth (sensitivity, 90.2%; specificity, 52.7%; negative predictive value, 84.3%). Conclusion: It is feasible to predict preterm birth by measuring the AF levels of IL-16 especially for the pregnant women requiring genetic amniocentesis during early second trimester.     

Prematurity,Subclinical Intraamniotic Infection,and Fetal Biophysical Parameters: Is There a Correlation?

Objective: This prospective study was undertaken to examine the effects of subclinical intraamniotic infection on fetal behavioral patterns.Methods: Amniotic fluid was obtained from four groups of patients (n = 99): group 1, patients with preterm premature rupture of the fetal membranes (PPROM) without infection; group 2, patients with PPROM and infection; group 3, patients with preterm labor (PTL) and without infection; and group 4, patients with PTL and infection. Fetal biophysical profiles were obtained on admission to the labor suite. Amniotic fluid was analyzed for the presence of microorganisms and endotoxin to confirm intraamniotic infection; cytokines interleukin (IL)-1beta, IL-6, and IL-8 were also assayed.Results: We found no association between low scores for biophysical parameters and subclinical infection in patients with PPROM or PTL.Conclusions: We could not demonstrate that upon a patient's admission to the labor hall absent fetal breathing and absent fetal movement, as well as reactivity, correlate with subclinical intraamniotic infection. Elevated cytokines, i.e. IL-1beta, IL-6, and IL-8 were associated with subclinical chorioamnionitis.     

Elevated amniotic fluid ferritin levels are associated with inflammation-related pregnancy loss following mid-trimester amniocentesis

Objective: Occult infection accounts for up to 12% of pregnancy losses following genetic amniocentesis. Elevated serum and cervical fluid levels of ferritin, an acute-phase reactant, have been associated with spontaneous preterm delivery. We determined the association between amniotic fluid (AF) ferritin levels and post-amniocentesis pregnancy loss. Methods: We performed a case-control study involving 66 women with a non-anomalous fetus who had a spontaneous pregnancy loss within 30 days following genetic amniocentesis and 66 term controls matched for maternal age, gestational age, time of test and indication for amniocentesis. Amniotic fluid ferritin and interleukin-6 (IL-6) levels were measured using commercially available kits. Results: Mean (± SD) AF ferritin levels were similar between the cases (19.3 ± 21.4 ng/ml) and the controls (19.8 ± 22.7 ng/ml) (p = 0.9). Mean (± SD) AF IL-6 levels were significantly higher in the women with post-amniocentesis pregnancy loss (4.0 ± 13.1 ng/ml) than in controls (0.5 ± 0.7 ng/ml) (p = 0.04). A significant proportion (12.1%, 8/66) of the women with postamniocentesis pregnancy loss had elevated amniotic fluid IL-6 levels (> 3 SD, 2.5 ng/ml) indicating inflammation, as compared to none in the control group (p = 0.01). In this subgroup of women with pregnancy loss and elevated IL-6 levels, AF ferritin levels were significantly elevated (52.0 ± 45.5 ng/ml) compared to the level in women who had a term delivery (19.8 ± 22.7 ng/ml) (p = 0.002), and were strongly correlated with IL-6 levels among the cases (r = 0.67, p < 0.001). Conclusion: The strong correlation of AF ferritin with IL-6 levels, along with the high ferritin values in cases with high AF IL-6, indicates that ferritin is a marker of inflammation in asymptomatic women destined to have an early pregnancy loss.     

Elevated concentrations of interleukin-6 in intra-amniotic infection with Ureaplasma urealyticum in asymptomatic women during genetic amniocentesis.

BACKGROUND: Intra-amniotic infection is an important cause of preterm delivery and interleukin-6 (IL-6) determination was recently applied for identification of microbial invasion of the amniotic cavity. Our aim was to determine the levels of IL-6 in culture-positive amniotic fluids at genetic amniocentesis and to evaluate their significance in relation to pregnancy outcome. METHODS: Seven culture-positive and 23 culture-negative amniotic fluids, obtained at 17-19 weeks of gestation, were analyzed for IL-6 levels by an immunoassay (ELISA). Pregnancy outcomes of all 30 women were obtained from the medical charts. RESULTS: The mean level of IL-6 in the culture-negative amniotic fluids was 78+/-206 pg/ml. Among the seven culture-positive, high levels of IL-6 were found only in three amniotic fluids that were culture-positive for Ureaplasma urealyticum (1834, 1342 and 2832 pg/ml). Low levels of IL-6, ranging from zero to 60 pg/ml, were found in four AFs that were culture-positive for Staphylococcus epidermidis (n=3) and Bacillus Gram-positive (n= 1). Adverse pregnancy outcome occurred in the three women who had intra-amniotic infection with U. urealyticum accompanied by high levels of IL-6 (two fetal loss and one preterm delivery at 28 weeks of gestation). The four women with culture-positive but IL-6 negative amniotic fluids, had normal pregnancy outcome and term delivery. Two of the 23 women with culture-negative had preterm delivery, one with high (1000 pg/ml) and one with low (80 pg/ml) levels of IL-6. CONCLUSION: High levels of IL-6 are suggestive of a genuine intra-amniotic infection with urea-plasmas resulting in adverse pregnancy outcome, while culture-positive amniotic fluids with normal IL-6 levels, may suggest a state of contamination.     

Maternal serum interleukin-6 and its association with clinicopathological infectious morbidity in preterm premature rupture of membranes: a prospective cohort study

Objective: To analyze the association of maternal serum interleukin-6 (IL-6) with fetomaternal outcome in preterm premature rupture of membranes (PPROM). Methods: Serial serum IL-6 levels were measured in 45 women with PPROM at gestation 24–34 weeks. The women were followed till pueperium and fetomaternal outcome as well as the histopathology of the placenta and the umblical cord was studied. The data were analyzed using t test and χ² test. Results: IL-6 levels ≥ 8 pg/ml were significantly associated with puerperal sepsis and neonatal sepsis. Histological chorioamnionitis and funisitis were demonstrated in 48.8% and 13.3% women respectively and significantly correlated with elevated serum IL-6 levels and fetomaternal infection. A cut-off value of IL-6 of 8 pg/ml was found to correctly diagnose 19 out of 23 patients with infectious morbidity and showed the best sensitivity (82.6%) and specificity (86.3%) as compared to the total leucocycte count (TLC) and C-reactive protein (CRP) in diagnosing infection in PPROM. Conclusion: Maternal serum IL-6 can be used as a biomarker to predict preclinical asymptomatic infection in PPROM with good sensitivity and specificity.