Maternal blood C-reactive protein, white blood cell count, and temperature in preterm labor: a comparison with amniotic fluid white blood cell count

Assessment of predictive markers for placental inflammatory response in preterm births

Placental inflammatory response (PIR) is associated with adverse neonatal outcomes such as sepsis, cerebral palsy, low birth weight, preterm birth, and neonatal mortality. However, there is an urgent need for noninvasive and sensitive biomarkers for prediction of PIR. In this study, we evaluated the clinical usefulness of maternal serum inflammatory markers for prediction of PIR in women with impending preterm birth. We conducted a retrospective cohort study of 483 patients who delivered preterm neonates. Serum levels of leukocyte differential counts, C-reactive protein (CRP), and neutrophil to lymphocyte ratio (NLR) were compared between women with no placental inflammation and women with PIR. The mean neutrophil counts, CRP levels, and NLR in both the patients with histologic chorioamnionitis (HCA) alone and those with HCA with funisitis were significantly higher than those in women with no placental inflammation. Compared to leukocyte subset or CRP, NLR in women with funisitis was significantly higher than in women with HCA alone and showed higher predictive accuracy, along with 71.4% sensitivity, 77.9% specificity, 80.7% positive predictive value, and 67.8% negative predictive value for prediction of PIR. On Kaplan-Meier survival analysis, women with both an elevated level of CRP and a high NLR had a shorter admission-to-delivery interval compared to women with either an elevated level of CRP or a high NLR alone. NLR may be a predictive marker of PIR and could be used as a cost-effective parameter for identifying women at risk of PIR.

Diagnostic and prognostic value of presepsin in preterm deliveries

PROBLEM

To evaluate the association between serum presepsin (soluble CD14 antigen subtype, sCD14-ST) levels soon after the appearance of signs of preterm delivery and preterm delivery within 48 h, before the 34th and 37th gestational weeks and the possible additional value of concurrently evaluated ultrasound vaginal cervicometry with serum presepsin measurement.

METHODOLOGY

A total of 60 females were included. Serum presepsin was measured by a chemiluminescent immunoassay. Sonographic evaluation of cervical length in all females was conducted by transvaginal ultrasound.

RESULTS

Patients who delivered within 48 h after analysis showed significantly higher presepsin concentrations compared to females with later deliveries. Higher presepsin was proven also for deliveries before/after weeks 34 and 37. A combined finding of cervical length shortening below 18 mm and presepsin level increasing above 623.5 pg/mL could point to the significantly high risk of preterm delivery.

CONCLUSION

Elevated maternal serum concentration of sCD14-ST could be an independent and relevant risk factor for preterm delivery.

Rate of sonographic cervical shortening and biologic pathways of spontaneous preterm birth

OBJECTIVE

The objective of the study was to estimate the relationship between midtrimester cervical length (CL) and maternal serum markers of systemic inflammation, activation of the maternal-fetal hypothalamic-pituitary axis, and alterations in thrombosis-hemostasis.

STUDY DESIGN

This is a secondary analysis of a prospective cohort study designed to predict preterm birth in the general obstetric population. Women had serial CL ultrasounds and assessment of maternal serum corticotrophin-releasing hormone, C-reactive protein, and thrombin-antithrombin III complexes between 20 and 33 weeks' gestation and were followed up until delivery.

RESULTS

Shortening of CL was associated with the rate of rise in corticotrophin-releasing hormone (r(2) = 0.34, P = .014) and C-reactive protein (r(2) = 0.44, P = .001) for women with CL less than 25 mm but not for the cohort overall. There was no association of change in CL with change in thrombin-antithrombin III concentration.

CONCLUSION

Among women with a midtrimester sonographically short cervix, changes in serum markers suggest that a shortening CL may be associated with systemic inflammation and activation of the maternal-fetal hypothalamic-pituitary axis but not systemic thrombosis-hemostasis.

A novel molecular microbiologic technique for the rapid diagnosis of microbial invasion of the amniotic cavity and intra-amniotic infection in preterm labor with intact membranes

PROBLEM

The diagnosis of microbial invasion of the amniotic cavity (MIAC) has been traditionally performed using traditional cultivation techniques, which require growth of microorganisms in the laboratory. Shortcomings of culture methods include the time required (days) for identification of microorganisms, and that many microbes involved in the genesis of human diseases are difficult to culture. A novel technique combines broad-range real-time polymerase chain reaction with electrospray ionization time-of-flight mass spectrometry (PCR/ESI-MS) to identify and quantify genomic material from bacteria and viruses.

METHOD OF STUDY

AF samples obtained by transabdominal amniocentesis from 142 women with preterm labor and intact membranes (PTL) were analyzed using cultivation techniques (aerobic, anaerobic, and genital mycoplasmas) as well as PCR/ESI-MS. The prevalence and relative magnitude of intra-amniotic inflammation [AF interleukin 6 (IL-6) concentration ≥ 2.6 ng/mL], acute histologic chorioamnionitis, spontaneous preterm delivery, and perinatal mortality were examined.

RESULTS

(i) The prevalence of MIAC in patients with PTL was 7% using standard cultivation techniques and 12% using PCR/ESI-MS; (ii) seven of ten patients with positive AF culture also had positive PCR/ESI-MS [≥17 genome equivalents per PCR reaction well (GE/well)]; (iii) patients with positive PCR/ESI-MS (≥17 GE/well) and negative AF cultures had significantly higher rates of intra-amniotic inflammation and acute histologic chorioamnionitis, a shorter interval to delivery [median (interquartile range-IQR)], and offspring at higher risk of perinatal mortality, than women with both tests negative [90% (9/10) versus 32% (39/122) OR: 5.6; 95% CI: 1.4-22; (P < 0.001); 70% (7/10) versus 35% (39/112); (P = 0.04); 1 (IQR: <1-2) days versus 25 (IQR: 5-51) days; (P = 0.002), respectively]; (iv) there were no significant differences in these outcomes between patients with positive PCR/ESI-MS (≥17 GE/well) who had negative AF cultures and those with positive AF cultures; and (v) PCR/ESI-MS detected genomic material from viruses in two patients (1.4%).

CONCLUSION

(i) Rapid diagnosis of intra-amniotic infection is possible using PCR/ESI-MS; (ii) the combined use of biomarkers of inflammation and PCR/ESI-MS allows for the identification of specific bacteria and viruses in women with preterm labor and intra-amniotic infection; and (iii) this approach may allow for administration of timely and specific interventions to reduce morbidity attributed to infection-induced preterm birth.

An elevated maternal serum C-reactive protein in the context of intra-amniotic inflammation is an indicator that the development of amnionitis, an intense fetal and AF inflammatory response are likely in patients with preterm labor: clinical implications

OBJECTIVE

We propose that an elevated maternal serum C-reactive protein (CRP) concentration in the context of intra-amniotic inflammation (IAI) is a predictor for amnionitis development, known to be the most advanced stage of maternal inflammatory response during the progression of acute histologic chorioamnionitis in preterm gestations.

METHODS

Study population consisted of 53 singleton gestations with IAI, who underwent amniocentesis due to preterm labor and intact membranes (PTL) and delivered preterm-neonates (<34.5 weeks) within 5 days of amniocentesis. The frequency of amnionitis and the intensity of fetal and amniotic fluid (AF) inflammatory response were examined according to the presence or absence of an elevated maternal serum CRP (≥0.7 mg/dL) at the time of amniocentesis. IAI was defined as an elevated AF matrix metalloproteinase-8 (MMP-8) (≥23 ng/mL), and fetal inflammatory response syndrome (FIRS) defined as an elevated umbilical cord plasma CRP (≥200 ng/mL).

RESULTS

(1) Patients (73.6%, 39/53) with an elevated maternal serum CRP had a significantly higher rate of amnionitis (59.0% versus 7.1%; p < 0.005), but not funisitis (46.2% versus 28.6%; p > 0.05), and higher median AF MMP-8 and umbilical cord plasma CRP concentration at birth than patients (26.4%,14/53) without that (AF MMP-8 (ng/mL): 373.1 versus 138.6: p = 0.05; umbilical cord plasma CRP (ng/mL): 363.4 versus 15.5: p < 0.05); (2) Multiple logistic regression analysis demonstrated that an elevated maternal serum CRP was a better independent predictor of amnionitis (odds ratio (OR), 12.5: 95% confidence interval (CI), 1.1-141.0; p < 0.05) than FIRS (OR, 3.6: 95% CI, 0.6-20.2; p = 0.150) and any other AF tests.

CONCLUSIONS

An elevated maternal serum CRP concentration in the context of IAI is an indicator that the development of amnionitis, an intense fetal and AF inflammatory response are likely in patients with PTL.

Positive maternal C-reactive protein predicts neonatal sepsis

PURPOSE

To evaluate the diagnostic performance of maternal inflammatory marker: C-reactive protein (CRP) in predicting early onset neonatal sepsis (that occurring within 72 hours after birth).

MATERIALS AND METHODS

126 low birth weight newborns (gestation 32±3.2 wk, birth weight 1887±623 g) and their mothers were included. Neonates were divided into sepsis group (n=51) including both proven (positive blood culture) and suspected (negative blood culture but with more than 3 abnormal clinical signs), and controls (n=75). Mothers were subgrouped into CRP positive ≥1.22 mg/dL (n=48) and CRP negative <1.22 mg/dL (n=78) group, determined by Receiver Operating Characteristic curves, and odds ratio was calculated for neonatal sepsis according to maternal condition.

RESULTS

Maternal CRP was significantly higher in neonatal sepsis group than in control (3.55±2.69 vs. 0.48±0.31 mg/dL, p=0.0001). Maternal CRP (cutoff value >1.22 mg/dL) had sensitivity 71% and specificity 84% for predicting neonatal sepsis. Maternal CRP positive group had more neonatal sepsis than CRP negative group (71% vs. 29%, p<0.001). Odds ratio of neonatal sepsis in maternal CRP positive group versus CRP negative group was 10.68 (95% confidence interval: 4.313-26.428, p<0.001).

CONCLUSION

The risk of early onset neonatal sepsis significantly increased in the case of positive maternal CRP (≥1.22 mg/dL). In newborn of CRP positive mother, the clinician may be alerted to earlier evaluation for possible neonatal infection prior to development of sepsis.

Soluble ST2, a modulator of the inflammatory response, in preterm and term labor

OBJECTIVE

Intra-amniotic infection/inflammation (IAI) is causally linked with spontaneous preterm labor and delivery. The ST2L receptor and its soluble form (sST2) are capable of binding to interleukin (IL)-33, a member of the IL-1 superfamily. Members of this cytokine family have been implicated in the onset of spontaneous preterm labor in the context of infection. Soluble ST2 has anti-inflammatory properties, and plasma concentrations are elevated in systemic inflammation, such as sepsis, acute pyelonephritis in pregnancy and the fetal inflammatory response syndrome. The aims of this study were to examine: (1) whether amniotic fluid concentrations of sST2 change with IAI, preterm, and term parturition; and (2) if mRNA expression of ST2 in the chorioamniotic membranes changes with acute histologic chorioamnionitis in women who deliver preterm.

METHOD

A cross-sectional study was conducted to determine amniotic fluid concentrations of sST2 in: (1) women with preterm labor (PTL) who delivered at term (n=49); (2) women with PTL who delivered preterm without IAI (n=21); (3) women with PTL who delivered preterm with IAI (n=31); (4) term pregnancies not in labor (n=13); and (5) term pregnancies in labor (n=43). The amniotic fluid concentration of sST2 was determined by ELISA. The mRNA expression of ST2 in the chorioamniotic membranes of women who delivered preterm with (n=24), and without acute histologic chorioamnionitis (n=19) was determined by qRT-PCR.

RESULTS

(1) Patients with PTL who delivered preterm with IAI had a lower median amniotic fluid concentration of sST2 compared to those with PTL who delivered preterm without IAI [median 410 ng/mL, inter-quartile range (IQR) 152-699 ng/mL versus median 825 ng/mL, IQR 493-1216 ng/mL; p=0.0003] and those with PTL who delivered at term [median 410 ng/mL, IQR 152-699 ng/mL versus median 673 ng/mL, IQR 468-1045 ng/mL; p=0.0003]; (2) no significant differences in the median amniotic fluid concentration of sST2 were observed between patients with PTL who delivered at term and those who delivered preterm without IAI (p=0.4), and between women at term in labor and those at term not in labor (p=0.9); (3) the mean mRNA expression of ST2 was 4-fold lower in women who delivered preterm with acute histologic chorioamnionitis than in those without this lesion (p=0.008).

CONCLUSIONS

The median sST2 amniotic fluid concentration and mRNA expression of ST2 by chorioamniotic membranes is lower in PTL associated with IAI and acute histologic chorioamnionitis than in PTL without these conditions. Changes in the median amniotic fluid sST2 concentration are not observed in preterm and term parturition without IAI. Thus, amniotic fluid sST2 in the presence of IAI behaves differently when compared to sST2 in the plasma of individuals affected by fetal inflammatory response syndrome, acute pyelonephritis in pregnancy, and adult sepsis. Decreased concentrations of sST2 in IAI are likely to promote a pro-inflammatory response, which is important for parturition in the context of infection.

Prediction and clinical relevance of pathologic patterns of injury associated with chorioamnionitis

The aim of the present study was to evaluate both prediction and clinical relevance of different patterns of injury associated with chorioamnionitis. Pathologic examination of placentas and umbilical cords were performed in 45 pregnant women who had had diagnostic amniocentesis for suspected intraamniotic infection. A positive correlation was noted between leukocyte account in amniotic fluid and the level of maternal injury (r = 0.46, p = 0.04). The levels of amniotic fluid glucose were significantly reduced in cases of fetal infection (2 mg/dL (1-16 mg/dL)) vs. (20.50 mg/dL (11-29 mg/dL)) (p = 0.03).

Intra-amniotic infection/inflammation as a risk factor for subsequent ruptured membranes after clinically indicated amniocentesis in preterm labor

The aim of this study was to determine whether intra-amniotic infection/inflammation (IAI) was associated with subsequent ruptured membranes in women with preterm labor and intact membranes who had a clinically indicated amniocentesis. This retrospective cohort study included 237 consecutive women with preterm labor (20-34.6 weeks) who underwent amniocentesis. The clinical and laboratory parameters evaluated included demographic variables, gestational age, C-reactive protein (CRP) and amniotic fluid (AF) white blood cell, interleukin-6 (IL-6) and culture results. IAI was defined as a positive AF culture and/or an elevated AF IL-6 level (>2.6 ng/mL). The primary outcome was ruptured membranes in the absence of active labor occurring within 48 hours of amniocentesis. Preterm premature rupture of membranes subsequently developed in 10 (4.2%) women within 48 hr of amniocentesis. Multivariate analysis demonstrated that only IAI was independently associated with the ruptured membranes occurring within 48 hr of amniocentesis. In the predictive model based on variables assessed before amniocentesis, only CRP level was retained. IAI is an independent risk factor for subsequent ruptured membranes after clinically indicated amniocentesis in preterm labor. Prior to amniocentesis, measurement of serum CRP level can provide a risk assessment for the subsequent development of ruptured membranes after the procedure.

Which is more important for the intensity of intra-amniotic inflammation between total grade or involved anatomical region in preterm gestations with acute histologic chorioamnionitis?

Objective

There is no data on which is more important for the intensity of intra-amniotic inflammation (IAI) between total grade or involved anatomical region in acute histologic chorioamnionitis (acute-HCA) of preterm-gestations. The objective of current study is to examine this issue.

Methods

The intensity of IAI was measured by amniotic fluid (AF) white blood cell (WBC) count and matrix metalloproteinase-8 (MMP-8) concentration in 225 singleton preterm-gestations (<36 weeks) who had acute-HCA including chorio-decidua involvement and delivered within 5 days of amniocentesis. Acute-HCA was defined in the presence of acute inflammatory changes in each anatomical region (i.e., chorio-decidua, amnion or chorionic plate). Patients were divided into 6 groups according to total grade (i.e., 1-6) and the presence or absence of chorio-decidua restriction (i.e., chorio-decidua restriction vs. extension beyond chorio-decidua) of acute-HCA.

Results

There was no significant difference in a median AF WBC and MMP-8 between the two groups (group-1, cases with total grade 1 vs. group-2, cases with total grade 2) among cases with chorio-decidua restriction (each for P>0.05) and between the four groups (group-3, cases with total grade 2 vs. group-4, cases with total grade 3 vs. group-5, cases with total grade 4 vs. group-6, cases with total grade 5-6) among cases with extension beyond chorio-decidua (each for P>0.05). However, group-3 (cases with extension beyond chorio-decidua) had a significantly higher median AF WBC and MMP-8 than group-2 (cases with chorio-decidua restriction) among cases with total grade 2 (each for P<0.05).

Conclusion

Involved anatomical region is more important than total grade for the intensity of IAI in acute-HCA of preterm-gestations.

Fetal, amniotic and maternal inflammatory responses in early stage of ascending intrauterine infection, inflammation restricted to chorio-decidua, in preterm gestation

OBJECTIVE

No data exist on the frequency and intensity of the fetal, intraamniotic and maternal inflammation in preterm-gestations with inflammation restricted to chorio-decidua, early stage of ascending intrauterine infection. The objective of the study is to examine this issue.

STUDY DESIGN

The frequency and intensity of fetal (cord blood C-reactive protein [CRP] at birth >200 ng/ml), intraamniotic (amniotic fluid matrix metalloproteinase-8 [MMP-8] >23 ng/ml) and maternal (maternal serum CRP >0.7 ng/ml) inflammation were compared in 304 singleton preterm-gestations (<35.4 weeks) delivered within 5 days of amniocentesis. Placental pathology was divided into placenta without any inflammation, inflammation restricted to chorio-decidua and inflammation beyond chorio-decidua.

RESULTS

Intraamniotic inflammation, but not fetal or maternal inflammation, was significantly more frequent (43.2% versus 10.5%; p < 0.005) and intense (median amniotic fluid MMP-8; 7.5 ng/ml versus 1.3 ng/ml; p < 0.001) in inflammation restricted to chorio-decidua than in placenta without any inflammation. However, inflammation restriced to chorio-decidua was associated with a significantly lower rate and intensity of fetal, intraamniotic and maternal inflammation than inflammation beyond chorio-decidua (each for p < 0.05).

CONCLUSION

Intraamniotic inflammation was more frequent and intense in patients with inflammation restricted to chorio-decidua than in those without placental inflammation. However, fetal and maternal inflammatory responses were similar between these two groups.

Soluble ST2 in the fetal inflammatory response syndrome: in vivo evidence of activation of the anti-inflammatory limb of the immune response

OBJECTIVE

Inflammation is a mechanism of host response to infection, which can be harmful when inappropriately modulated. Soluble ST2 (sST2) is a decoy receptor of interleukin (IL)-33, and this complex modulates the balance in the Th1/Th2 immune response. Moreover, sST2 inhibits the production of pro-inflammatory cytokines in cooperation with an anti-inflammatory cytokine, IL-10. The objectives of this study were to: (1) determine whether umbilical cord plasma sST2 concentration differs between preterm neonates with and without funisitis and between those with and without the fetal inflammatory response syndrome (FIRS); and (2) evaluate the relationship between sST2 and IL-10 among neonates with funisitis and/or FIRS.

METHODS

Umbilical cord plasma was collected from neonates delivered prematurely due to preterm labor or preterm prelabor rupture of membranes with (n = 36), and without funisitis (n = 30). FIRS (umbilical cord IL-6 concentration ≥ 17.5 pg/mL) was identified in 29 neonates. Plasma sST2 and IL-10 concentrations were determined by enzyme linked immune sorbent assay.

RESULTS

The median umbilical cord plasma sST2 concentration was 6.7-fold higher in neonates with FIRS than in those without FIRS (median 44.6 ng/mL, interquartile range (IQR) 13.8-80.3 ng/mL versus median 6.7 ng/mL, IQR 5.6-20.1 ng/mL; p < 0.0001). Similarly, the median umbilical cord plasma sST2 concentration was 2.7-fold higher in neonates with funisitis than in those without funisitis (median 19.1 ng/mL; IQR 7.1-75.0 ng/mL versus median 7.2 ng/mL; IQR 5.9-23.1 ng/mL; p = 0.008). There was a strong positive correlation between sST2 and IL-10 in neonates with funisitis and/or FIRS (Spearman's Rho = 0.7, p < 0.0001).

CONCLUSION

FIRS and funisitis are associated with an elevation of umbilical cord plasma concentrations of soluble ST2. This protein represents an important mediator of the immune response in neonates diagnosed with FIRS by promoting an anti-inflammatory effect in association with IL-10.

The frequency and clinical significance of intra-amniotic inflammation defined as an elevated amniotic fluid matrix metalloproteinase-8 in patients with preterm labor and low amniotic fluid white blood cell counts

Objective

To determine the frequency and clinical significance of intra-amniotic inflammation (IAI) defined as an elevated amniotic fluid (AF) matrix metalloproteinase-8 (MMP-8) concentration in patients with preterm labor and intact membranes (PTL) and low AF white blood cell (WBC) counts.

Methods

Adverse pregnancy outcomes were compared according to the presence or absence of IAI in 220 singleton gestations who underwent amniocentesis due to PTL (gestational age<35.7 weeks) and had low AF WBC counts (<19 cells/mm³). Adverse pregnancy outcomes included preterm birth within 5 days of amniocentesis, acute histologic chorioamnionitis (acute-HCA) and positive AF culture. IAI was defined as an elevated AF MMP-8 concentration (≥23 ng/mL).

Results

IAI was present in 19% of study population. Adverse pregnancy outcomes were significantly more frequent in patients with IAI than in those without IAI (preterm birth within 5 days of amniocentesis, 88% vs. 41%; acute-HCA, 47% vs. 11%; positive AF culture, 10% vs. 2%; each for P<0.05). Patients with IAI had a significantly shorter median amniocentesis-to-delivery interval than those without IAI (7.8 hours [0.01-3,307.3 hours] vs. 310.3 hours [0.01-2,973.8 hours]; P<0.001 from survival analysis). Multiple logistic regression analysis demonstrated that only an IAI (odds ratio, 3.3; 95% confidence interval, 1.5-7.3; P<0.005) retained a statistical significance in the prediction of acute-HCA after other confounding variables were adjusted.

Conclusion

Approximately one-fifth of patients with PTL and low AF WBC counts have an evidence of IAI and are at risk for impending preterm delivery and acute-HCA when AF MMP-8 concentration is used.

A fetal and an intra-amniotic inflammatory response is more severe in preterm labor than in preterm PROM in the context of funisitis: unexpected observation in human gestations

Objective

Although intra-amniotic(IA) infection is present in both preterm labor and intact membranes(PTL) and preterm premature rupture of membranes(preterm-PROM), it is more common in preterm-PROM than in PTL. Microorganisms and their products in the amniotic-cavity can elicit an inflammatory-response in fetus as well as in amniotic-cavity in the progression of acute histologic chorioamnionitis(acute-HCA). A fundamental question is whether a fetal and an IA inflammatory-response is more severe in preterm-PROM than in PTL, in the same-context of acute-HCA with or without fetal-involvement. The purpose of current-study was to answer this-question.

Study-Design

Study population consisted of 213 singleton preterm-gestations(<34 weeks) delivered within 4 days of amniocentesis due to PTL(120 cases) or preterm-PROM(93 cases). The intensity of fetal and IA inflammatory-responses was compared between PTL and preterm-PROM, according to placental inflammatory conditions:1)placenta without inflammatory-lesion;2)acute-HCA without funisitis;3)acute-HCA with funisitis. IA inflammatory response was assessed by amniotic-fluid(AF) matrix metalloproteinase-8(MMP-8), and fetal inflammatory response(FIR) by umbilical-cord plasma(UCP) C-reactive protein(CRP) at birth.

Results

1) Patients with preterm-PROM had higher rates of IA infection, acute-HCA, and acute-HCA with funisitis than those with PTL did(p<.01 for each);2) there were no significant differences in the intensity of fetal and IA inflammatory-responses and the rate of cervical dilatation≥3 cm or 4 cm between patients with PTL and those with preterm-PROM in the context of both placenta without inflammatory-lesion and acute-HCA without funisitis(p>.05 for each);3) however, acute-HCA with funisitis was associated with a significantly higher median AF MMP-8 and UCP CRP concentration and higher rate of cervical dilatation≥3 cm or 4 cm in PTL than in preterm-PROM(AF MMP-8, 675 ng/mlvs.417 ng/ml; UCP CRP, 969 ng/mlvs.397 ng/ml;each for p<.05), despite less common IA infection in PTL than in preterm-PROM(29%vs.57%;p<.05).

Conclusions

A fetal and an IA inflammatory-response is more severe in PTL than in preterm-PROM in the context of funisitis, despite less common IA infection. This unexpected observation may indicate the fundamental difference in the pathogenesis between PTL and preterm-PROM.

Increased number of cerebellar granule cells and astrocytes in the internal granule layer in sheep following prenatal intra-amniotic injection of lipopolysaccharide

Chorioamnionitis is an important problem in perinatology today, leading to brain injury and neurological handicaps. However, there are almost no data available regarding chorioamnionitis and a specific damage of the cerebellum. Therefore, this study aimed at determining if chorioamnionitis causes cerebellar morphological alterations. Chorioamnionitis was induced in sheep by the intra-amniotic injection of lipopolysaccharide (LPS) at a gestational age (GA) of 110 days. At a GA of 140 days, we assessed the mean total and layer-specific volume and the mean total granule cell (GCs) and Purkinje cell (PC) number in the cerebelli of LPS-exposed and control animals using high-precision design-based stereology. Astrogliosis was assessed in the gray and white matter (WM) using a glial fibrillary acidic protein staining combined with gray value image analysis. The present study showed an unchanged volume of the total cerebellum as well as the molecular layer, outer and inner granular cell layers (OGL and IGL, respectively), and WM. Interestingly, compared with controls, the LPS-exposed brains showed a statistically significant increase (+20.4%) in the mean total number of GCs, whereas the number of PCs did not show any difference between the two groups. In addition, LPS-exposed animals showed signs of astrogliosis specifically affecting the IGL. Intra-amniotic injection of LPS causes morphological changes in the cerebellum of fetal sheep still detectable at full-term birth. In this study, changes were restricted to the inner granule layer. These cerebellar changes might correspond to some of the motor or non-motor deficits seen in neonates from compromised pregnancies.

The frequency and clinical significance of intra-amniotic inflammation in women with preterm uterine contractility but without cervical change: do the diagnostic criteria for preterm labor need to be changed?

OBJECTIVE

The objective of this study was to determine the frequency and clinical significance of intra-amniotic inflammation in patients with preterm increased uterine contractility with intact membranes but without cervical change.

METHODS

Amniocentesis was performed in 132 patients with regular uterine contractions and intact membranes without cervical change. Amniotic fluid was cultured for bacteria and mycoplasmas and assayed for matrix metalloproteinase-8 (MMP-8). Intra-amniotic inflammation was defined as an elevated amniotic fluid MMP-8 concentration (>23 ng/mL).

RESULTS

(1) Intra-amniotic inflammation was present in 12.1% (16/132); (2) Culture-proven intra-amniotic infection was diagnosed in 3% (4/132) of patients without demonstrable cervical change on admission or during the period of observation; and (3) Patients with intra-amniotic inflammation had significantly higher rates of preterm delivery and adverse outcomes, and shorter amniocentesis-to-delivery intervals than those without intra-amniotic inflammation (P < 0.05 for each). Adverse outcomes included chorioamnionitis, funisitis, and neonatal death.

CONCLUSION

Intra-amniotic inflammation was present in 12% of patients with regular uterine contractions without cervical change, while culture-proven intra-amniotic infection was present in 3%. The presence of intra-amniotic inflammation was a significant risk factor for adverse neonatal outcomes. These observations question whether cervical changes should be required for the diagnosis of preterm labor, because patients without modifications in cervical status on admission or during a period of observation are at risk for adverse pregnancy outcomes.

Relationship between maternal serum C-reactive protein, funisitis and early-onset neonatal sepsis

The aim of this study was to determine whether maternal serum C-reactive protein (CRP) is of value in predicting funisitis and early-onset neonatal sepsis (EONS) in women with preterm labor or preterm premature rupture of membranes (PROM). This retrospective cohort study included 306 consecutive women with preterm labor or preterm PROM who delivered preterm singleton neonates (23-35 weeks gestation) within 72 hr of CRP measurement. The CRP level was measured with a highly sensitive immunoassay. The sensitivity, specificity, positive predictive value, and negative predictive value of an elevated serum CRP level (≥ 8 mg/L) were 74.1%, 67.5%, 32.8%, and 92.4% for funisitis, and 67.7%, 63.3%, 17.2%, and 94.6% for EONS, respectively. Logistic regression analysis demonstrated that elevated levels of serum CRP were significantly associated with funisitis and EONS, even after adjusting gestational age. The maternal serum CRP level obtained up to 72 hr before delivery is an independent predictor of funisitis and EONS in women with preterm labor or preterm PROM. A low serum CRP level (< 8 mg/L) has good negative predictive value in excluding funisitis and EONS, and may therefore be used as a non-invasive adjunct to clinical judgment to identify low-risk patients.

[The role of infection in preterm birth]

Intrauterine infection could be responsible for 25% up to 40% of preterm births. This relationship was initially demonstrated using animal models, inducing their abortion by injecting bacteria or endotoxins. In human research, examination of amniocentesis fluid showed the anteriority of infection over labor induction, and the existence of a subclinical latency phase between these two phenomena. The ascending route is preponderant, and four stages can be distinguished: cervical and vaginal infection, chorio-decidual infection, intra-amniotic infection, fetal infection. The intrauterine infection is very frequent in case of early preterm birth (<30 WG). It is associated with an increase of neurological and pulmonary morbidity. Most commonly found bacterial species are mycoplasma species, but also Escherichia coli, Gardnerella vaginalis and streptococcus B. Several markers of the infection have been studied: a maternal leukocytosis>15,000/mm(3) or a C-Reactive Protein (CRP)>20mg/l, an increase of fibronectin and/or IL-6 cervical, a short cervical length especially before 32 WG, a leukocytosis of the amniotic fluid, and/or high interleukin concentrations. The main marker used for the newborn is the CRP, but other markers can also be used for an early diagnosis of an infection, especially interleukin 6.

Predictive value of intra-amniotic and serum markers for inflammatory lesions of preterm placenta

OBJECTIVE

To compare the relative predictive values of amniotic fluid (AF) matrix metalloproteinase-9 (MMP-9), interleukin-6 (IL-6), and serum C-reactive protein (CRP) for histologic chorioamnionitis and intra-amniotic infection in women with preterm labor or preterm premature rupture of membranes (PROM).

STUDY DESIGN

This retrospective cohort study included 99 consecutive women with preterm labor or preterm PROM (21-35 weeks' gestation) who delivered within 72 h of transabdominal amniocentesis. The AF was cultured for aerobic and anaerobic bacteria and for genital mycoplasmas and was assayed for MMP-9 and IL-6 levels. Maternal serum CRP was measured immediately after amniocentesis. The placentas were examined histologically.

MAIN OUTCOME MEASURES

histologic chorioamnionitis and intra-amniotic infection.

RESULTS

The prevalence of histologic chorioamnionitis and a positive AF culture was 44% (44/99) and 28% (28/99), respectively. In predicting intra-amniotic infection, AF MMP-9 had a significantly higher area under the curve (AUC: 0.94 [95% CI, 0.87-0.98]) than AF IL-6 (0.87 [95% CI, 0.78-0.84]; P < 0.05) and serum CRP (0.76 [95% CI, 0.66-0.84]; P < 0.001) and a higher sensitivity and specificity than serum CRP (P < 0.01, respectively). However, in predicting histologic chorioamnionitis, there were no significant differences in AUCs among the three tests (AF MMP-9: 0.78 [95% CI, 0.68-0.85]; AF IL-6: 0.76 [95% CI, 0.66-0.84]; serum CRP: 0.76 [95% CI, 0.66-0.84]). In a sub-analysis of 71 women without intra-amniotic infection, histologic chorioamnionitis was associated with an elevated serum CRP level (P < 0.05), but not with the level of AF IL-6 or MMP-9 (P = 0.232 and P = 0.402, respectively).

CONCLUSIONS

The AF MMP-9 has a better overall diagnostic performance than the AF IL-6 and maternal serum CRP in predicting intra-amniotic infection. However, the serum CRP level obtained up to 72 h before delivery appears to be an important marker for early identification of histologic chorioamnionitis in women without intra-amniotic infection.

Maternal plasma lipopolysaccharide binding protein (LBP) concentrations in pregnancy complicated by preterm premature rupture of membranes

OBJECTIVES

To compare maternal plasma LBP concentrations in pregnancies complicated by preterm premature rupture of membranes (pPROM), and PROM at term, with their levels in uncomplicated pregnancy, and to determine whether LBP concentrations are of value in the diagnosis of subclinical intra-amniotic infection (IAI) in the prediction of the length of the pPROM-to-delivery interval, and in the prediction of neonatal congenital infection.

STUDY DESIGN

Thirty-one patients with pPROM, 35 with PROM at term, 33 healthy women at preterm gestation and 35 healthy women at term were included. In the pPROM group, analysis of maternal plasma LBP concentrations with reference to leukocytosis, C-reactive protein, vaginal fluid culture, neonatal infection and pPROM-to-delivery interval was carried out.

RESULTS

LBP concentrations in the four studied groups were comparable. Although in 58.1% of pPROM cases at least one laboratory parameter of infection was observed, the only difference concerned the subgroup with CRP above 10mg/L, in which LBP concentrations were higher. Comparison of LBP concentrations in patients delivered within 24 and 72h of pPROM and after these times showed no differences, or between patients who gave birth to newborns with and without congenital infection. The predictive values of these measurements were poor.

CONCLUSION

The predictive value of maternal LBP determinations in the diagnostics of pPROM cases suspected of IAI is unsatisfactory. LBP measurements performed shortly after pPROM, are not of value either in the prediction of newborn's infection, or in the prognosis of latency period duration.

Non-invasive prediction of intra-amniotic inflammation in women with preterm labor

OBJECTIVE

To develop a model based on non-invasive variables to predict the probability of intra-amniotic inflammation in women with preterm labor and intact membranes.

METHODS

Transvaginal ultrasonography and digital examination for the assessment of cervical length and cervical dilatation were performed, and maternal blood was collected for the determination of C-reactive protein and white blood cell (WBC) count immediately after amniocentesis in 153 consecutive women with preterm labor. Amniotic fluid obtained by amniocentesis was cultured for aerobic and anaerobic bacteria and mycoplasmas, and the WBC was determined. Intra-amniotic inflammation was defined as an elevated amniotic fluid interleukin-6 concentration (> 2.6 ng/mL). Receiver-operating characteristics (ROC) curves and logistic regression analysis were used for statistical analysis.

RESULTS

The prevalence of a positive amniotic fluid culture was 7.2% (11/153) and the prevalence of intra-amniotic inflammation was 19.6% (30/153). The final logistic regression model was based on non-invasive clinical variables, including gestational age at assessment, cervical length and maternal blood WBC count, which were the best predictors of intra-amniotic inflammation. The model was shown to have an adequate goodness of fit (P = 0.754), and the area under the ROC curve was 0.724, indicating reasonably good discrimination.

CONCLUSION

In women with preterm labor and intact membranes, the risk for intra-amniotic inflammation can be predicted non-invasively with a risk score based on gestational age, cervical length and maternal blood WBC count.

Maternal serum and vaginal fluid C-reactive protein levels do not predict early-onset neonatal infection in preterm premature rupture of membranes

OBJECTIVE

The aim of this study was to evaluate the usefulness of maternal serum and vaginal fluid C-reactive protein (CRP) determinations in the prediction of neonatal congenital infection.

STUDY DESIGN

Fifty women between 24 and 36 weeks gestation, complicated by preterm premature rupture of membranes (pPROM), were divided into two groups according to the presence (n=14) or absence (n=36) of early-onset newborns' infection.

RESULT

Maternal serum and vaginal fluid CRP concentrations were comparable between both groups. Serum CRP levels ≥10 and ≥15 mg l(-1) predicted neonatal infection with a sensitivity of 47 and 47%, specificity of 63 and 76%, positive predictive value (PPV) of 38 and 47%, and negative predictive value (NPV) of 72 and 76%, respectively. The cutoff value of vaginal CRP ≥2.4 mg l(-1) predicted infection with a sensitivity of 71%, specificity of 47%, PPV of 34%, and NPV of 81%. Receiver-operating characteristic curve analysis revealed that the predictive performance of CRP was poor.

CONCLUSION

Maternal serum and vaginal fluid CRP determinations after pPROM are of poor predictive value in neonatal early-onset infection prediction.

Maternal serum interleukin-6, C-reactive protein, and matrix metalloproteinase-9 concentrations as risk factors for preterm birth <32 weeks and adverse neonatal outcomes

Elevated concentrations of interleukin-6 (IL-6), C-reactive protein (CRP), and matrix metalloproteinase-9 (MMP-9) in fetal and neonatal compartments have been associated with an increased risk for preterm birth (PTB) and/or neonatal morbidity. The purpose of this study was to determine if the maternal serum concentration of IL-6, CRP, and MMP-9 in women at risk for PTB, who are not in labor and have intact membranes, are associated with an increased risk for PTB <32 weeks and/or neonatal morbidity. Maternal serum samples collected from 475 patients enrolled in a multicenter randomized controlled trial of single versus weekly corticosteroids for women at increased risk for preterm delivery were assayed. Serum was collected at randomization (24 to 32 weeks' gestation). Maternal serum concentrations of IL-6, CRP, and MMP-9 were subsequently determined using enzyme-linked immunoassays. Multivariate logistic regression analysis was performed to explore the relationship between maternal serum concentrations of IL-6, CRP, and MMP-9 and PTB <32 weeks, respiratory distress syndrome (RDS), chronic lung disease (CLD), intraventricular hemorrhage (IVH), necrotizing enterocolitis (NEC), and any sepsis. Maternal serum concentrations of IL-6 and CRP, but not MMP-9, above the 90th percentile at the time of randomization were associated with PTB <32 weeks. In contrast, there was no significant relationship between RDS and NEC and the maternal serum concentration of IL-6, CRP, or MMP-9 (univariate analysis). The development of CLD was associated with a high (above 90th percentile) IL-6 and CRP in maternal serum, even after adjustment for gestational age (GA) at randomization and treatment group. However, when GA at delivery was added to the model, this finding was nonsignificant. Neonatal sepsis was more frequent in neonates born to mothers with a high maternal serum concentration of CRP (>90th percentile). However, there was no significant association after adjustment for GA at randomization and treatment group. Logistic regression analysis for each analyte indicated that high maternal serum concentrations of IL-6 and CRP, but not MMP-9, were associated with an increased risk of IVH (odds ratio [OR] 4.60, 95% confidence interval [CI] 1.86 to 10.68; OR 4.07, 95% CI 1.63 to 9.50) after adjusting for GA at randomization and treatment group. Most babies (25/30) had grade I IVH. When GA at delivery was included, elevated IL-6 remained significantly associated with IVH (OR 2.77, 95% CI 1.02 to 7.09). An elevated maternal serum concentration of IL-6 and CRP are risk factors for PTB <32 weeks and subsequent development of neonatal IVH. An elevated maternal serum IL-6 appears to confer additional risk for IVH even after adjusting for GA at delivery.

Isobaric labeling and tandem mass spectrometry: a novel approach for profiling and quantifying proteins differentially expressed in amniotic fluid in preterm labor with and without intra-amniotic infection/inflammation

OBJECTIVE

Examination of the amniotic fluid (AF) proteome has been previously attempted to identify useful biomarkers in predicting the outcome of preterm labor (PTL). Isobaric Tag for Relative and Absolute Quantitation (iTRAQ) labeling allows direct ratiometric comparison of relative abundance of identified protein species among multiplexed samples. The purpose of this study was to apply, for the first time, the combination of iTRAQ and tandem mass spectrometry to identify proteins differentially regulated in AF samples of women with spontaneous PTL and intact membranes with and without intra-amniotic infection/inflammation (IAI).

METHODS

A cross-sectional study was designed and included AF samples from patients with spontaneous PTL and intact membranes in the following groups: (1) patients without IAI who delivered at term (n = 26); (2) patients who delivered preterm without IAI (n = 25); and (3) patients with IAI (n = 24). Proteomic profiling of AF samples was performed using a workflow involving tryptic digestion, iTRAQ labeling and multiplexing, strong cation exchange fractionation, and liquid chromatography tandem mass spectrometry. Twenty-five separate 4-plex samples were prepared and analyzed.

RESULTS

Collectively, 123,011 MS(2) spectra were analyzed, and over 25,000 peptides were analyzed by database search (X!Tandem and Mascot), resulting in the identification of 309 unique high-confidence proteins. Analysis of differentially present iTRAQ reporter peaks revealed many proteins that have been previously reported to be associated with preterm delivery with IAI. Importantly, many novel proteins were found to be up-regulated in the AF of patients with PTL and IAI including leukocyte elastase precursor, Thymosin-like 3, and 14-3-3 protein isoforms. Moreover, we observed differential expression of proteins in AF of patients who delivered preterm in the absence of IAI in comparison with those with PTL who delivered at term including Mimecan precursor, latent-transforming growth factor beta-binding protein isoform 1L precursor, and Resistin. These findings have been confirmed for Resistin in an independent cohort of samples using ELISA. Gene ontology enrichment analysis was employed to reveal families of proteins participating in distinct biological processes. We identified enrichment for host defense, anti-apoptosis, metabolism/catabolism and cell and protein mobility, localization and targeting.

CONCLUSIONS

(1) Proteomics with iTRAQ labeling is a profiling tool capable of revealing differential expression of proteins in AF; (2) We discovered 82 proteins differentially expressed in three clinical subgroups of premature labor, 67 which were heretofore unknown. Of particular importance is the identification of proteins differentially expressed in AF from women who delivered preterm in the absence of IAI. This is the first report of the positive identification of biomarkers in this subgroup of patients.

The frequency and clinical significance of intra-uterine infection and inflammation in patients with placenta previa and preterm labor and intact membranes

OBJECTIVE

Histologic placental and/or intra-amniotic inflammation is frequently documented during ascending intra-uterine infections in patients with preterm labor and intact membranes. Placenta previa can be a clinical situation that shows the successive schema of histologic placental and intra-amniotic inflammation during the process of ascending intra-uterine infections. However, a paucity of information exists about the frequency and clinical significance of intra-uterine infections and inflammation in patients with placenta previa and preterm labor and intact membranes. The purpose of this study was to examine this issue.

STUDY DESIGN

Amniocentesis was performed on 42 patients with placenta previa and preterm labor and intact membranes (gestational age <37 weeks). Amniotic fluid (AF) was cultured for aerobic and anaerobic bacteria and genital mycoplasmas, and AF white blood cell (WBC) count and matrix metalloproteinase-8 (MMP-8) concentrations were determined. The diagnosis of intra-amniotic inflammation was made in patients with an elevated AF MMP-8 (> or =23 ng/ml). Non-parametric statistics were used for analysis.

RESULTS

1) Intra-amniotic inflammation was present in 16.7% (7/42), proven AF infection in 4.9% (2/41), and histologic chorioamnionitis in 19.0% (8/42) of patients with placenta previa and preterm labor; 2) Patients with intra-amniotic inflammation had significantly higher rates of a positive AF culture, histologic chorioamnionitis, funisitis, and a shorter interval-to-delivery than those without intra-amniotic inflammation (p<0.05 for each); 3) Among patients with histologic chorioamnionitis, inflammation of the choriodecidua, which was exposed to the cervical canal, existed in all cases (8/8), but inflammation of the chorionic plate existed in 63% of patients (5/8); 4) Patients with inflammation of the chorionic plate had significantly higher median AF MMP-8 concentrations and WBC counts, and higher rates of intra-amniotic inflammation than those in whom inflammation was restricted to choriodecidua (p<0.05 for each).

CONCLUSIONS

Placental inflammation was present in 19.0% and intra-amniotic inflammation was present in 16.7% of patients with placenta previa and preterm labor and intact membranes. The intra-amniotic inflammatory response was stronger when inflammation was present in the chorionic plate and choriodecidua, than when it was restricted to the choriodecidua only, which was exposed to the cervical canal in placenta previa.

Transvaginal ultrasonographic measurement of cervical length in predicting intra-amniotic infection and impending preterm delivery in preterm labor: a comparison with amniotic fluid white blood cell count

AIMS

To determine whether sonographic measurement of cervical length predicts intra-amniotic infection and impending preterm delivery (within 7 days of amniocentesis) in women with preterm labor and intact membranes, and to compare the predictability with that of amniotic fluid (AF) white blood cell (WBC) count.

METHODS

Transvaginal ultrasonographic assessment of cervical length was performed immediately after amniocentesis in 67 consecutive women with preterm labor. AF obtained by amniocentesis was cultured for aerobic and anaerobic bacteria and for Mycoplasmas, and WBC count was determined.

RESULTS

Patients with a positive AF culture had a significantly shorter median cervical length, higher median AF WBC count, and lower median gestational age at delivery than did those with a negative AF culture. Multivariate analysis indicated that only the AF WBC count bears a significant relationship with the presence of intra-amniotic infection, whereas only cervical length correlates with impending preterm delivery.

CONCLUSIONS

Transvaginal sonographic measurements of cervical length are a valuable method for predicting intra-amniotic infection as well as impending preterm delivery in women with preterm labor. However, in comparison with AF WBC, cervical length is less predictive for intra-amniotic infection, whereas cervical length demonstrates better predictability of impending preterm delivery.

The involvement of human amnion in histologic chorioamnionitis is an indicator that a fetal and an intra-amniotic inflammatory response is more likely and severe: clinical implications

OBJECTIVE

Amnionitis (inflammation of the amnion) is the final stage of extra-placental chorioamniotic inflammation. We propose that patients with "amnionitis", rather than "chorionitis" have a more advanced form of intra-uterine inflammation/infection and, thus, would have a more intense fetal and intra-amniotic inflammatory response than those without "amnionitis".

STUDY DESIGN

The relationship between the presence of amnionitis, and a fetal and an intra-amniotic inflammatory response was examined in 290 singleton preterm births (<or=36 weeks) with histologic chorioamnionitis. The fetal inflammatory response was determined by plasma C-reactive protein (CRP) concentrations in umbilical cord and the presence of funisitis. The intra-amniotic inflammatory response was assessed by matrix metalloproteinase-8 (MMP-8) concentration and white blood cell (WBC) count in 156 amniotic fluid (AF) samples obtained within 5 days of birth. AF was cultured for aerobic and anaerobic bacteria and genital mycoplasmas. The CRP concentration was measured with a highly sensitive immunoassay.

RESULTS

(1) Amnionitis was present in 43.1% of cases with histologic chorioamnionitis. (2) Patients with amnionitis had a significantly higher rate of funisitis and positive AF culture and a higher median umbilical cord plasma CRP, AF MMP-8 level and AF WBC count than those without amnionitis (p<0.001 for each). (3) Among cases with amnionitis, the presence or absence of funisitis was not associated with significant differences in the median cord plasma CRP, AF MMP-8 level and AF WBC count. (4) However, the presence of amnionitis in cases with funisitis was associated with a higher median umbilical cord plasma CRP, AF MMP-8 level and AF WBC count than the absence of amnionitis in those with funisitis (p<0.05 for each). (5) Multiple logistic regression analysis demonstrated that amnionitis was a better independent predictor of proven or suspected early-onset neonatal sepsis (odds ratio 3.8, 95% confidence interval (CI) 1.1-13.2, p<0.05) than funisitis (odds ratio 1.8, 95% CI 0.5-6.1, not significant) after correction for the contribution of other potential confounding variables.

CONCLUSION

The involvement of the amnion in the inflammatory process of the extraplacental membranes is associated with a more intense fetal and intra-amniotic inflammatory response than chorionitis alone. This observation has clinical implications because it allows staging of the severity of the inflammatory process and assessment of the likelihood of fetal involvement.

Host factors in amniotic fluid and breast milk that contribute to gut maturation

The gut represents a complex organ system with regional differences, which reflect selective digestive and absorptive functions that change constantly in response to bodily requirements and the outside milieu. As a barrier to the external environment, gut epithelium must be renewed rapidly and repeatedly. Growth and renewal of gut epithelial cells is dependent on controlled cell stimulation and proliferation by a number of signaling processes and agents, including gut peptides-both endogenous and exogenous sources. This cascade of events begins during fetal development; with the ingestion of amniotic fluid, this process is enhanced and continued during infancy and early childhood through the ingestion of human milk. Events influenced by amniotic fluid during fetal development and those influenced by human milk that unfold after birth and early childhood to render the gut mature are presented.

Prediction of preterm birth in symptomatic women using decision tree modeling for biomarkers

OBJECTIVE

The objective of the study was to use recursive partitioning (RP) to identify gestational age-specific and threshold values for infectious and endocrine biomarkers of imminent delivery.

STUDY DESIGN

RP was developed using a previously collected data set and then applied to a prospectively collected cohort of women in threatened preterm labor. Predictors of preterm birth were considered, including white blood cell count (WBC), corticotrophin-releasing hormone (CRH), cortisol, and maternal age.

RESULTS

At 22-27 weeks' gestation, WBC of greater than 12,000/mL was the most accurate predictor of delivery within 48 hours; at 28-31 weeks' gestation, CRH of greater than 684 pg/mL was the most accurate predictor; and at 32-26 weeks' gestation, CRH and maternal age were the most important variables.

CONCLUSIONS

These results indicate that maternal WBC greater than 12,000/mL prior to 28 weeks' gestation and CRH beyond 28 weeks are the most accurate biomarkers in predicting preterm birth within 48 hours. RP assists in establishing clinically relevant and gestational age-specific threshold levels for these variables.

The cost of urogynaecological treatments: Which are more cost-effective?

AIMS

To determine the cost-effectiveness of four urogynaecological treatments.

MATERIALS

Two prospective trials were performed in which 205 women with urinary incontinence underwent urogynaecological treatments. The cost incurred and the improvement in quality of life (QOL) as a result of treatment was calculated as cost/quality-adjusted life year (QALY) and then ranked in order of cost-effectiveness.

RESULTS

The Nurse Continence Advisor (NCA) group (N = 73) and the Urogynaecologist (UG) group (N = 72) both had significant improvements in leaks per week and incontinence score. QOL improvement was also similar (1.5% vs 1.2%). The economic data found a similar improvement in pad usage costs ($A2.90 vs $A3.52). The clinician costs were significantly lower for the NCA group ($A60.00 vs $A105.00) (P < 0.0001). The cost per QALY was significantly lower for the NCA group ($A28,009 vs $A35,312) (P = 0.03). Both groups had significant improvements in pad testing and leaks per week. The cure/improvement rates were also similar at three months (100% vs 89%). There was no significant difference in the improvement in QOL between the laparoscopic colposuspension (LC) and open colposuspension (OC) groups (2.09% vs 1.54%). The economic data found a similar improvement in pad usage costs ($A11.74 vs $A16.17). The theatre costs were significantly higher for the LC group ($A403.45 vs $A266.94) (P < 0.0001), however the overall costs were significantly lower ($A4,668 vs $A6,124) (P < 0.0001). The cost/QALY was lower for the LC group ($A63,980 vs $A134,069), however this did not reach significance.

CONCLUSIONS

Overall, on comparison of the cost/QALY's, conservative treatment of urinary incontinence by a NCA was the most cost-effective.

Functional anatomy of the female pelvic floor

The anatomic structures in the female that prevent incontinence and genital organ prolapse on increases in abdominal pressure during daily activities include sphincteric and supportive systems. In the urethra, the action of the vesical neck and urethral sphincteric mechanisms maintains urethral closure pressure above bladder pressure. Decreases in the number of striated muscle fibers of the sphincter occur with age and parity. A supportive hammock under the urethra and vesical neck provides a firm backstop against which the urethra is compressed during increases in abdominal pressure to maintain urethral closure pressures above the rapidly increasing bladder pressure. This supporting layer consists of the anterior vaginal wall and the connective tissue that attaches it to the pelvic bones through the pubovaginal portion of the levator ani muscle, and the uterosacral and cardinal ligaments comprising the tendinous arch of the pelvic fascia. At rest the levator ani maintains closure of the urogenital hiatus. They are additionally recruited to maintain hiatal closure in the face of inertial loads related to visceral accelerations as well as abdominal pressurization in daily activities involving recruitment of the abdominal wall musculature and diaphragm. Vaginal birth is associated with an increased risk of levator ani defects, as well as genital organ prolapse and urinary incontinence. Computer models indicate that vaginal birth places the levator ani under tissue stretch ratios of up to 3.3 and the pudendal nerve under strains of up to 33%, respectively. Research is needed to better identify the pathomechanics of these conditions.

A prospective observational trial of pelvic floor muscle training for female stress urinary incontinence

OBJECTIVE

To assess the impact of pelvic floor muscle training (PFMT) on bladder neck mobility in a prospective observational study, and to correlate any observed changes with objective, standardized outcome measures of the severity of stress urinary incontinence (SUI).

PATIENTS AND METHODS

Women with the symptom of SUI were recruited prospectively over a 3-year period from a tertiary referral urogynaecology clinic in a teaching hospital. A group of 97 treatment-naive women complaining of SUI and confirmed as having urodynamic SUI on video-urodynamic assessment agreed to participate. Bladder neck mobility on perineal ultrasonography was assessed immediately before and on completing a 14-week programme of 'PFM rehabilitation'. Treatment outcome was assessed using a standardized pad-test and a condition-specific, validated quality-of-life questionnaire (King's Health Questionnaire). Changes in functional anatomy were quantified using transperineal ultrasonography to measure the bladder neck position at rest, maximum PFM contraction and maximum Valsalva manoeuvre. Bladder neck rotational mobility from rest to maximum incursion and maximum excursion was calculated.

RESULTS

Treatment with an intensive package of PFMT and behavioural modification resulted in significant elevation of the bladder neck position at all three measured positions. Displacement of the bladder neck on Valsalva (rotational excursion) was reduced after treatment, suggesting increased levator 'stiffness'. These changes in functional anatomy were associated with a statistically and clinically significant reduction in urine loss and improvement in condition-specific quality of life.

CONCLUSION

The present results show that PFMT is an effective treatment for SUI and provide an important new insight into how dynamic pelvic floor anatomy can be modified by this widely used intervention.

Periodontitis and plasma C-reactive protein during pregnancy

BACKGROUND

Periodontitis has been associated with increased risk of adverse pregnancy outcomes and elevated C-reactive protein (CRP) concentrations in non-pregnant adults. We examined the relationship between periodontitis and CRP among women who provided dental radiographs and had blood collected during early pregnancy, excluding smokers and diabetic patients.

METHODS

From Project Viva, an ongoing cohort study, we measured plasma CRP in 35 subjects with periodontitis (i.e., at least one site with > or =3 mm of alveolar bone loss) and a random sample of 66 periodontally healthy subjects matched on age and race/ethnicity. We performed linear regression analysis with log-transformed CRP levels as the outcome.

RESULTS

The mean (+/- SE) CRP level was 65% higher (95% confidence interval: -2%, 180%; P = 0.06) in women with periodontitis (2.46 +/- 0.52 mg/l) than in controls (1.49 +/- 0.22 mg/l), adjusting for factors related to CRP levels, including age, race/ethnicity, pre-pregnancy body mass index, alcohol intake, education, income, and gestational age at blood collection.

CONCLUSIONS

These findings suggest that periodontitis may increase CRP levels in pregnancy. CRP could potentially mediate the association of periodontitis with adverse pregnancy outcomes.

Physiotherapy for female stress urinary incontinence: a multicentre observational study

BACKGROUND

No previous data are available on the effectiveness of physiotherapy management of urinary stress incontinence with relevance to the Australian health system.

AIMS

To evaluate Australian ambulatory physiotherapy management of stress urinary incontinence.

METHODS

Observational multicentre clinical study of physiotherapy management of female stress urinary incontinence between February 1999 and October 2000, with 1-year follow-up. Outcome measures were a stress test and a 7-day diary of incontinent episodes (pretreatment and at every visit) and a condition-specific quality of life (QoL) questionnaire (pre- and post-treatment). Subjects were followed-up 1 year after treatment by questionnaire with a 7-day diary, QoL questionnaire, and assessment of subjective outcome, subjective cure, satisfaction and need for surgery.

RESULTS

Of the 274 consenting subjects, 208 completed an episode of physiotherapy care consisting of a median (IQ range) of five (four to six) visits. At the end of the episode, 84% were cured and 9% improved on stress testing, whilst 53% were cured and 25% improved according to the 7-day diary. Mean volume of urine loss on stress testing reduced from 2.4 (2.5) mL to 0.1(0.4) mL after treatment. There was a significant improvement in all QoL domains. Median (interquartile range) incontinent episodes per week were reduced from five (three to 11) to zero (zero to two) (P < 0.05) after treatment and to one (zero to four) at 1 year (P < 0.05). At 1 year, approximately 80% of respondents had positive outcomes on all outcome measures.

CONCLUSIONS

Physiotherapy management in Australian clinical settings is an effective treatment option for women with stress urinary incontinence.

A short cervix in women with preterm labor and intact membranes: a risk factor for microbial invasion of the amniotic cavity

OBJECTIVE

The purpose of this study was to determine whether there was a relationship between sonographic cervical length and the presence of culture-proven microbial invasion of the amniotic cavity in women with preterm labor and intact membranes.

STUDY DESIGN

Ultrasonography and amniocentesis were performed in 401 patients admitted with preterm labor (22-35 weeks) and cervical dilatation of < or = 3 cm, as assessed by digital examination. Cervical length was determined by transvaginal ultrasound at admission. Outcome variables were the presence of microbial invasion of the amniotic cavity (defined as a positive amniotic fluid culture) and the occurrence of preterm delivery before 35 weeks. Contingency tables, chi2 test, receiver-operator characteristic (ROC) curves, and logistic regression were used for statistical analysis.

RESULTS

The prevalence of microbial invasion of the amniotic cavity was 7% (28/401). Spontaneous preterm delivery (< or = 35 weeks) occurred in 21.4% (82/384) of patients. ROC curve analysis showed a significant relationship between the frequency of microbial invasion of the amniotic cavity and the length of the uterine cervix (area under the curve: 0.77; P < .005). Patients with a cervical length < 15 mm had a higher rate of a positive amniotic fluid culture than patients with a cervical length > or = 15 mm (26.3% [15/57] vs. 3.8% [13/344], respectively; P < .05). Moreover, patients with a short cervix (defined as < 15 mm) were more likely to deliver spontaneously before 35 weeks, 32 weeks, within 7 days, and within 48 hours of admission ( P < .05 for all comparisons). Forty percent of patients (161/401) had a cervical length > or = 30 mm. These patients had a very low risk of microbial invasion of the amniotic cavity (1.9% [3/161]), spontaneous delivery < or = 35 weeks (4.5% [7/154]), < or = 32 weeks (2.6% [2/76]), within 7 days (1.9% [3/154]), and within 48 hours (0% [0/154]) of admission.

CONCLUSION

Endovaginal ultrasonographic examination of the uterine cervix in women with preterm labor identifies patients at increased risk for intrauterine infection.

Animal models of preterm birth

Preterm birth continues to pose a significant clinical dilemma and contributes to both acute and long-term neonatal morbidity. Despite efforts, the incidence of preterm birth has not decreased, partly because of our lack of understanding of the mechanisms that trigger parturition. Animal models are essential research tools for investigating the pathways that promote preterm parturition and for testing therapeutic interventions. Growing evidence correlates infection or inflammation with preterm birth. Consequently, many investigators have created animal models that reflect these findings. Current models of preterm parturition include diverse species, varying means of inducing an inflammatory or infectious state, and different routes of administration. Although each of these models can advance our knowledge, it is important to understand their advantages, disadvantages and unique characteristics. An understanding of such models will hopefully promote continued research that will ultimately lead to a decrease in preterm birth and an improvement in neonatal outcome.

Proinflammatory cytokines and other indications of inflammation in cervico-vaginal secretions and preterm delivery

OBJECTIVES

To compare the usefulness of evaluating cervico-vaginal concentrations of proinflammatory cytokines (interleukin [IL]-1alpha, IL-1beta, IL-6 and IL-8) and procalcitonin (PCT), as well as serum levels of C-reactive protein (CRP), leucocytosis and band form granulocytes in the prediction of preterm delivery (PTD).

METHODS

A total of 65 pregnant women experiencing preterm labor (PTL) were enrolled in the study. Concentrations of the studied markers in women who delivered prematurely and in women who, after treatment, delivered at term were compared. Receiver operator characteristic (ROC) curve analysis was used for all study parameters.

RESULTS

Cervico-vaginal IL-6 and procalcitonin as well as serum CRP concentrations were higher in women who delivered prematurely than in those who delivered near term. A cervico-vaginal IL-6 level greater than 660 pg/ml was the best predictive value of preterm delivery (sensitivity, 50%; specificity 90%; positive predictive value [PPV], 85%; NPV, 62%; likelihood ratio, 5.17). Moreover, the area under the ROC curve of 0.75 for cervico-vaginal IL-6 was greater than for other markers.

CONCLUSION

Although cervico-vaginal concentrations of procalcitonin and serum concentration of CRP are higher in women who deliver prematurely, only cervico-vaginal concentration of IL-6 is a good predictor of preterm delivery.

The effect of betamethasone administration to pregnant women on maternal serum indicators of infection

OBJECTIVE

To study the effect of betamethasone therapy on maternal white blood cell count, C-reactive protein and erythrocyte sedimentation rate in women at high risk for preterm delivery.

STUDY DESIGN

We included women at gestational age of 24 to 34 weeks who were treated by betamethasone for enhancement of fetal lung maturity, because of imminent preterm labor with intact membranes. Blood tests for white blood cell and differential count, C-reactive protein and erythrocyte sedimentation rate were drawn before betamethasone injection, 2 hours after, and then every 24 hours for three days.

RESULTS

105 women were included. The mean white blood cell count increased by 33% on day one, and returned to baseline level three days after the first injection of betamethasone. A significant rise in neutrophil count, and drop in lymphocyte count was noted as early as two hours after the first injection and lasted for two days. Mean C-reactive protein and erythrocyte sedimentation rate levels were not changed significantly by betamethasone treatment.

CONCLUSIONS

Antenatal betamethasone therapy causes a transient increase in maternal leukocyte count but has no effect on serum C-reactive protein and erythrocyte sedimentation rate. This information is relevant for preterm pregnant women who are at high risk for chorioamnionitis.

The effects of anesthetic techniques on acute phase response at delivery (anesthesia and acute phase response)

OBJECTIVES

To investigate the effects of anesthetic techniques and delivery types on stress response during uncomplicated delivery.

DESIGN AND METHODS

Forty pregnant women at term were divided into four groups. Group-I, cesarean section with general anesthesia; Group-II, section with spinal anesthesia; Group-III, section with epidural anesthesia; and Group-IV, vaginal delivery with epidural analgesia. C-reactive protein and albumin were measured on hospital admission, immediately after delivery and 24 h later.

RESULTS

Albumin and CRP levels decreased significantly in Group-II and Group-III, just after delivery. CRP increased significantly in all groups at the 24(th) hour of delivery. The effect of hemodilution on CRP and Albumin, due to volume loading, during spinal and epidural anesthesia disappeared after 24 h.

CONCLUSION

We found no influence of anesthetic techniques on acute phase response except hemodilution effect. In the view of delivery types, vaginal delivery caused less stress response than section.

Microbial invasion and cytokine response in amniotic fluid in a Swedish population of women in preterm labor

BACKGROUND

Previous studies indicate an association between intra-amniotic microbial invasion and/or inflammation and spontaneous preterm birth, but there is a limited amount of data available from Europe. The aim of this study was to investigate the occurrence of intra-amniotic microorganisms and cytokines (interleukin-6 and interleukin-8) in a Swedish population of women in preterm labor and their correlation with preterm birth.

METHODS

Amniotic fluid was retrieved transabdominally from 61 patients in preterm labor before 34 weeks of gestation. Polymerase chain reaction analyses for Ureaplasma urealyticum and Mycoplasma hominis and culture for aerobic and anaerobic bacteria were performed. Interleukin-6 and interleukin-8 were analyzed with enzyme-linked immunosorbent assay.

RESULTS

Microorganisms in amniotic fluid were detected in 10 patients (16%). Patients with detected bacteria in the amniotic fluid had significantly higher levels of interleukin-6 and interleukin-8. There was also an association between interleukin-6/-8, the amniocentesis-delivery interval (<or= 7 days) and preterm birth (<34 weeks). An amniotic fluid concentration of interleukin-6 >or= 1.5 ng/mL or interleukin-8 >or= 1.3 ng/mL was associated with an increased risk of delivery within 7 days (interleukin-6: relative risk 7.3; 95% confidence interval: 2.8-19; sensitivity 83%, specificity 87%; interleukin-8: relative risk 14, 95% confidence interval: 3.6-55, sensitivity 91%, specificity 87%).

CONCLUSIONS

The occurrence of intra-amniotic microbial invasion and inflammation in this population of Swedish women in preterm labor was similar to data reported from populations with a higher incidence of preterm delivery. Amniotic interleukin-6 and interleukin-8 correlated with the presence of microorganisms and with preterm birth.

Evidence of participation of soluble CD14 in the host response to microbial invasion of the amniotic cavity and intra-amniotic inflammation in term and preterm gestations

OBJECTIVE

Endotoxin has been implicated in the mechanism responsible for the setting of infection in preterm labor. To exert its biological effects, endotoxin binds to a circulating protein known as lipopolysaccharide binding protein (LBP) and presents endotoxin monomers to CD14, which may be a membrane-bound receptor or a soluble molecule. The endotoxin-LBP-CD14 complex interacts with Toll-like receptor 4 and other regulatory proteins leading to cellular activation and an inflammatory response. The purpose of this study was to determine whether microbial invasion of the amniotic cavity (MIAC)/intra-amniotic inflammation (both preterm and term) and parturition at term are associated with changes in the amniotic fluid and umbilical plasma soluble concentrations of CD14 (sCD14).

STUDY DESIGN

Amniotic fluid was retrieved by amniocentesis from 88 patients in the following groups: group 1, preterm labor with intact membranes with MIAC/intra-amniotic inflammation (n = 18) and without these conditions (n = 26); group 2, term gestations not in labor without MIAC/intra-amniotic inflammation (n = 11), in labor without MIAC/intra-amniotic inflammation (n = 12) and in labor with MIAC/intra-amniotic inflammation (n = 13); and group 3, patients who underwent genetic amniocentesis at mid-trimester (n = 8). A sample of cord blood was obtained after delivery in all patients except those in group 3. sCD14 was assayed with a sensitive and specific immunoassay. Non-parametric statistics were used for analysis. A p value of < 0.05 was considered significant.

RESULTS

sCD14 was detectable in 97% (85/88) of the amniotic fluid samples. Amniotic fluid sCD14 concentrations were lower in patients at term than in the mid-trimester of pregnancy (mid-trimester: median 482 ng/ml, range 258-838 ng/ml vs. term no labor: median 7 ng/ml, range 2-274 ng/ml, p = 0.01). Among patients with preterm labor with intact membranes, the median amniotic fluid sCD14 level of patients with MIAC/intra-amniotic inflammation was higher than in patients without these conditions (median 1568 ng/ml, range 98-5887 ng/ml vs. median 645 ng/ml, range 0-3961 ng/ml, respectively; p = 0.01). Among women at term in labor, those with MIAC/intra-amniotic inflammation had a higher median amniotic fluid sCD14 concentration than those without these conditions (median 85 ng/ml, range 2-1113 ng/ml vs. median 17 ng/ml, range 0-186 ng/ml; p = 0.01). MIAC/intra-amniotic inflammation in women with preterm labor with intact membranes was associated with a higher median umbilical venous plasma sCD14 concentration (median 744 ng/ml, range 0-3620 ng/ml vs. median 0 ng/ml, range 0-2060 ng/ml; p = 0.04). sCD14 was undetectable in plasma from umbilical cords of all neonates born to women at term. An increase in amniotic fluid concentration of sCD14 was observed in cases of intrauterine infection, not only by gram-negative bacteria, but also gram-positive bacteria and Ureaplasma spp.

CONCLUSION

sCD14 is a physiological constituent of amniotic fluid, and its concentrations at term are lower than in the mid-trimester. Intrauterine infection/inflammation is associated with a higher median amniotic fluid sCD14 concentration in both preterm and term parturition. Neonates born from mothers with preterm labor with intact membranes and MIAC/intra-amniotic inflammation had a higher median concentration of sCD14 in umbilical cord plasma than those without these conditions. sCD14 concentrations are increased in the amniotic fluid and umbilical cord blood even in the absence of a microbiologically proven gram-negative infection. CD14 appears to participate in the host response to intrauterine infection even in cases involving genital mycoplasmas.

Intrauterine infection and prematurity

Intrauterine infection is a major cause of premature labor with and without intact membranes. Intrauterine infection is present in approximately 25% of all preterm births and the earlier the gestational age at delivery, the higher the frequency of intra-amniotic infection. Microorganisms may also gain access to the fetus before delivery. A fetal inflammatory response syndrome elicited in response to microbial products is associated with the impending onset of preterm labor and also with multi-systemic organ involvement in the human fetus and a higher rate of perinatal morbidity. The most common microorganisms involved in intrauterine infections are Ureaplasma urealyticum, Fusobacterium species and Mycoplasma hominis. The role of Chlamydia trachomatis and viruses in preterm labor remain to be determined. Use of molecular microbiology techniques to diagnose intrauterine infection may uncover the role of fastidious microorganisms that have not yet been discovered. Antibiotic administration to patients with asymptomatic bacteriuria is associated with a significant reduction in the rate of preterm birth. However, such benefit has not been demonstrated for patients with bacterial vaginosis, or women who carry Streptococcus agalactia, Ureaplasma urealyticum or Trichomonas vaginalis. Antibiotic administration to patients with preterm premature rupture of membranes is associated with prolongation of pregnancy and a reduction in the rate of clinical chorioamnionitis and neonatal sepsis. The benefit has not been demonstrated in patients with preterm labor and intact membranes. Major efforts are required to determine why some women develop an ascending intrauterine infection and others do not and also what interventions may reduce the deleterious effect of systemic fetal inflammation.

C-reactive protein: a serological marker for preterm delivery?

BACKGROUND

We studied the association between the C-reactive protein level in the maternal serum early in the second trimester with that in preterm delivery.

METHODS

The present study is a prospective nested case-control study including 84 singleton, preterm deliveries (cases) and 400 singleton, term deliveries (controls), based at the Odense University Hospital, Denmark. These cases were identified from a cohort of 2846 women, monitored from their first prenatal care visit until their delivery. All the participants were examined at enrollment (median 16.3 weeks of gestation). Conventional statistical methods were used for analyses.

RESULTS

We found statistically significant differences in the C-reactive protein levels measured in early pregnancy between the women delivering preterm and those delivering at term. Different statistically significant odds ratios of between 1.7 and 2.0 were calculated, depending on the C-reactive protein level's cut-off value, and ranged from 5.6 mg/l (75th percentile) to 16.4 mg/l (95th percentile). The highest level was achieved at the 85th percentile (7.6 mg/l); odds ratio 2.0 (95%CI, 1.2-3.5).

CONCLUSION

A high C-reactive protein level at the beginning of a pregnancy is associated with a nearly twofold increased risk of preterm delivery; however, the clinical value at this point is still limited.

Bacterially induced preterm labor in the mouse does not require maternal interleukin-1 signaling

OBJECTIVE

We tested the hypothesis that intrauterine bacterial inoculation induces labor via expression of the inflammatory cytokine interleukin-1 (IL-1) in a murine model.

STUDY DESIGN

Pregnant mice on day 14.5 of a 19-20 day gestation were inoculated with killed Escherichia coli or sterile media into either (a) the right uterine horn, (b) the right uterine horn following its surgical isolation from the contralateral horn and cervix, or (c) the kidney. Cytokine levels in gestational tissues and maternal serum were determined by use of enzyme-linked immunosorbent assay (ELISA). In a separate experiment, bacterially induced preterm delivery was compared between mice lacking a functional IL-1 receptor and wild-type control litter mates.

RESULTS

Killed E coli induced delivery within 48 hours with similar dose-response curves regardless of inoculation site (intact uterine horn, isolated uterine horn, or kidney). Bacterial inoculation of an isolated right horn caused dramatic increases in local expression of IL-1 and IL-6. However, delivery occurred from the uninjected horn without corresponding upregulation of cytokines, with the exception of a modest rise within fetal membranes. Mice lacking a functional IL-1 receptor were no different from wild-type mice in their susceptibility to bacterially induced delivery.

CONCLUSION

Bacterially induced labor in the murine model does not require IL-1 signaling.