Requirement of major histocompatibility complex-compatible microenvironment for spleen colony formation (CFU-S on day 12 but not on day 8)

The objectives of this study were 1) to evaluate interleukin-8 concentrations in cervical secretions in predicting preterm delivery, microbial invasion of the amniotic cavity and histologic chorioamnionitis in patients with preterm labor and intact membranes and 2) to compare the diagnostic value of interleukin-8 with fetal fibronectin determinations in predicting preterm delivery, microbial invasion of the amniotic cavity and histologic chorioamnionitis in patients with preterm labor and intact membranes. Interleukin-8 and fetal fibronectin were assayed in cervical secretions in 106 patients with singleton pregnancies and intact membranes admitted for preterm labor. Amniotic fluid obtained by amniocentesis was cultured and placentas (No = 43) analyzed for the presence of chorioamnionitis. The prevalence of pregnancies delivered preterm was 46.2% (49/106) and 15.09% (16/106) of amniotic fluid cultures were positive. Interleukin-8 levels in cervical secretions were significantly increased in patients who delivered preterm (p < or = 0.0001), in presence of positive amniotic fluid culture (p = 0.0016) and histological chorioamnionitis (p = 0.008) than in patients with negative findings. Receiver-operator characteristics curve analysis showed that an interleukin-8 value > 450 pg/ml is comparable to that of a fetal fibronectin value > 50 ng/ml in predicting preterm delivery (p = 0.247). Among patients who delivered preterm interleukin-8 concentrations > 860 pg/ml predicted a positive amniotic fluid culture with a sensitivity of 81.2% and a specificity 66.6%. Further, in patients who delivered preterm and had a negative amniotic fluid culture, IL-8 concentrations > 480 pg/ml predicted histological chorioamnionitis with a sensitivity 78.5% and specificity 61.5%. A positive fetal fibronectin > 50 ng/ml was not predictve of either a positive amniotic fluid culture or the presence of histological chorioamnionitis. In conclusion, increased concentrations of interleukin-8 and fetal fibronectin are associated with impending delivery and their diagnostic value seems comparable. However, interleukin-8 concentrations identify patients at risk of a positive amniotic fluid culture and the presence of histological chorioamnionitis. Measurement of interleukin-8 in cervical secretion is a non-invasive method to identify patients at risk for both preterm delivery and intrauterine infection.     

Evidence of participation of the soluble tumor necrosis factor receptor I in the host response to intrauterine infection in preterm labor

PROBLEM: This study was conducted to determine whether: (1) the soluble tumor necrosis factor receptor I (sTNF-rI) is present in human amniotic fluid, neonatal urine, and the feto-maternal plasma; (2) there are changes in the concentration of the sTNF-rI in amniotic fluid with gestational age; and (3) microbial invasion of the amniotic cavity (in term and preterm parturition) is associated with changes in amniotic fluid sTNF-rI concentrations. METHOD: Amniotic fluid was retrieved by amniocentesis from 185 women classified into 11 groups according to gestational age (midtrimester, preterm gestation, and term), the presence or absence of labor, spontaneous rupture of membranes and microbial invasion of the amniotic cavity. sTNF-rI was assayed with a sensitive and enzyme-linked immunosorbent assay (ELISA) validated for amniotic fluid. In addition, sTNF-rI concentrations were determined in fetal blood obtained by cordocentesis in preterm gestations (N = 24) or at the time of delivery after spontaneous labor at term (N = 10). sTNF-rI concentrations were also measured in maternal venous and cord blood and neonatal urine (n = 13). RESULTS: sTNF-rI was found to be present in all amniotic fluid samples, maternal blood and fetal blood and neonatal urine samples; sTNF-rI concentrations were higher in the midtrimester than at term (mean +/- SD: 36.2 +/- 12.2 ng/ml versus mean +/- SD: 5.56 +/- 5.72 ng/ml [P < .05]); patients with preterm labor and microbial invasion of the amniotic cavity (with intact or with ruptured membranes) had significantly higher amniotic fluid concentrations of sTNF-rI than patients without microbial invasion; in the absence of microbial invasion, parturition (both term and preterm) was not associated with changes in amniotic fluid concentrations of sTNF-rI; neonatal urine contained the highest concentrations of sTNF-rI of all biological fluids assayed including maternal and neonatal/fetal blood and amniotic fluid. CONCLUSIONS: It was concluded that sTNF-rI is a physiologic constituent of amniotic fluid, as well as of the fetal and maternal plasma; that amniotic fluid sTNF-rI concentrations decrease as a function of gestional age and increases in the concentration of the sTNF-rI are part of the host response to intrauterine infection in preterm parturition.     

The value of amniotic fluid interleukin-6, white blood cell count, and gram stain in the diagnosis of microbial invasion of the amniotic cavity in patients at term

PROBLEM: Subclinical microbial invasion of the amniotic cavity occurs in 18.8% of women with term labor and intact membranes and in 34% of patients with term PROM and is a risk factor for the development of puerperal infection related morbidity. Although amniotic fluid white blood cell count, interleukin-6 determination, and Gram stain examination have been used for the diagnosis of intrauterine infection in patients with preterm labor and preterm premature rupture of membranes, no information is available about the accuracy and specific cut-off values for these tests in patients at term. The purpose of this study was to compare the performance of the amniotic fluid Gram stain examination, white blood cell count, and interleukin-6 determination in the identification of microbial invasion of the amniotic cavity in patients at term with and without PROM. METHOD: Amniotic fluid was retrieved from 148 patients with term gestations (90 patients with spontaneous labor and intact membranes and 58 patients with PROM). Samples were cultured for bacteria and Mycoplasma species. Amniotic fluid Gram stain, white blood cell count, and interleukin-6 determinations (ELISA, sensitivity: 43 pg/ml) were performed in all samples. Microbial invasion of the amniotic cavity was defined as a positive amniotic fluid culture for microorganisms. Analysis was conducted using Mann-Whitney U test, Fisher's exact test, receiver operating characteristic curves and logistic regression. RESULTS: Patients with spontaneous labor and intact membranes: The prevalence of microbial invasion of amniotic cavity in this group was 15.6% (14/90). The most sensitive test for the detection of microbial invasion of the amniotic cavity was amniotic fluid interleukin-6 determination (sensitivity for: interleukin-6 > or = 5.7 ng/ml = 86%, white blood cell count > or = 20 cells/mm3 = 64%, Gram stain = 28%). The most specific test was the Gram stain of the amniotic fluid (specificity for: Gram stain = 84%, interleukin-6 = 79% and white blood cell count = 63%). Multiple logistic regression demonstrated that amniotic fluid interleukin-6 concentration was the only covariate that retained statistical significance when intrauterine infection was used as outcome variable. Patients with PROM: The prevalence of a positive amniotic fluid culture in this group was 39.7% (23/58). Logistic regression demonstrated that only interleukin-6 retained a significant relationship with the results of amniotic culture when all variables were entered simultaneously into a model to predict amniotic fluid culture results. The most sensitive tests for the detection of intrauterine infection were interleukin-6 determination and white blood cell count (sensitivity for interleukin-6 > or = 3.4 ng/ml and white blood cell count > or = 20 cells/mm3 = 69.6% for both). The most specific test was Gram stain (97.1%). CONCLUSIONS: Amniotic fluid interleukin-6 determination is the best rapid test for the detection of microbial invasion of the amniotic cavity in patients at term with and without PROM. When this test is not available, amniotic fluid Gram stain and white blood cell count represent valid diagnostic tools to assess the microbial state of amniotic cavity.     

The role of amniotic fluid L-selectin, GRO-alpha, and interleukin-8 in the pathogenesis of intraamniotic infection

OBJECTIVE: Our purpose was to compare and correlate amniotic fluid GRO-alpha, interleukin-8, and L-selectin in patients with and without intraamniotic infection. STUDY DESIGN: Amniocentesis was performed on 45 pregnant women with preterm contractions, labor, or rupture of membranes. Fourteen patients had intraamniotic infection, and 31 did not. Intraamniotic infection was defined as the presence of a positive amniotic fluid culture. Amniotic fluid tests for Gram stain, glucose, neutrophil counts, creatinine, pH, and specific gravity were performed. Amniotic fluid levels of soluble L-selectin, interleukin-8, and GRO-alpha were measured by an enzyme-linked immunoassay and normalized by amniotic fluid creatinine levels. The Mann-Whitney Utest and Spearman's rank correlation test were used for statistical analyses. RESULTS: Amniotic fluid median levels of soluble L-selectin, interleukin-8, and GRO-alpha were significantly higher in pregnant women with intraamniotic infection than in those without intraamniotic infection (soluble L-selectin: median 3334.6 ng/mg creatinine, range 408.4 to 15,956.8 vs 717.2 ng/mg creatinine, range 129.4 to 4601.9, p = 0.009; GRO-alpha: median 841.6 ng/mg creatinine, range 28.1 to 8591.7 vs 56.8 ng/mg creatinine, range 0.0 to 440.2, p < 0.0001; interleukin-8: median 4932.7 ng/mg creatinine, range 0.0 to 55,058.7 vs 28.3 ng/mg creatinine, range 0.0 to 1161.6, p = 0.0004). Patients with intraamniotic infection had significantly higher amniotic fluid leukocyte counts and leukocyte esterase activities and significantly lower amniotic fluid glucose concentrations compared with those without intraamniotic infection. Amniotic fluid GRO-alpha, interleukin-8, and soluble L-selectin were positively correlated, and each was positively correlated with amniotic fluid leukocytes and negatively correlated with amniotic fluid levels of glucose. CONCLUSIONS: Our data indicate amniotic fluid GRO-alpha and interleukin-8 may be two potent leukocyte chemoattractants and activators, and L-selectin is rapidly shed from leukocytes in the amniotic fluid in patients with intraamniotic infection.     

What use are fibromyalgia control points?

OBJECTIVE: Our purpose was to determine whether early second-trimester amniotic fluid interleukin-6 levels predict delivery before 34 weeks' gestation. STUDY DESIGN: We used stored second-trimester amniotic fluid samples obtained from women undergoing genetic amniocentesis from 1988 to 1996. Interleukin-6 levels were measured by enzyme-linked immunosorbent assay in samples from every case known to result in delivery from 20 to 34 weeks' gestation (n = 290), and 290 matched controls delivering at > or =37 weeks. Fetal aneuploidies, anomalies, and all cases delivering within 30 days of the amniocentesis (which were thought to be possibly procedure related) were excluded. RESULTS: Interleukin-6 levels were higher in cases than controls (1.9 +/- 5.2 vs 1.0 +/- 2.4 ng/ml, p = 0.004). Cases were grouped according to whether the preterm delivery was indicated or spontaneous: The mean interleukin-6 levels were significantly higher than controls in the spontaneous group (1.6 +/- 3.2 vs 0.8 +/- 1.2 ng/ml, p = 0.01) but not in the indicated group (1.4 +/- 4.0 vs 0.8 +/- 1.2 ng/ml, p = 0.12). In all samples the interleukin-6 level was negatively correlated with the gestational age at delivery (R = -0.11633, p = 0.007). CONCLUSION: Elevated early second-trimester amniotic fluid interleukin-6 levels are associated with preterm delivery, confirming that in some women this indicator of very early intrauterine inflammation predicts birth before 34 weeks' gestation.     

Amniotic fluid cytokines (interleukin-6, tumor necrosis factor-alpha, interleukin-1 beta, and interleukin-8) and the risk for the development of bronchopulmonary dysplasia

OBJECTIVE: Our purpose was to test the hypothesis that neonates who develop bronchopulmonary dysplasia have higher amniotic fluid concentrations of proinflammatory cytokines than those who do not develop bronchopulmonary dysplasia. STUDY DESIGN: The relationship between amniotic fluid concentrations of interleukin-6, tumor necrosis factor-alpha, interleukin-1 beta, and interleukin-8 and the occurrence of bronchopulmonary dysplasia in the neonate was examined in 69 patients who were delivered of preterm neonates (< or = 33 weeks) within 5 days of amniocentesis. Cytokines were measured by specific immunoassays. RESULTS: Bronchopulmonary dysplasia was diagnosed in 19% (13/69) of newborns. Median amniotic fluid concentrations of interleukin-6, tumor necrosis factor-alpha, interleukin-1 beta, and interleukin-8 concentrations were significantly higher in mothers whose infants had bronchopulmonary dysplasia than in mothers whose infants did not have bronchopulmonary dysplasia (p < 0.05 for each). Neonates who had bronchopulmonary dysplasia were delivered at earlier gestational ages and had lower birth weights than those without bronchopulmonary dysplasia. The differences in median amniotic fluid interleukin-6, interleukin-1 beta, and interleukin-8 between these two groups remained significant after we adjusted for the effect of gestational age at birth (p < 0.05 for each). CONCLUSIONS: (1) Antenatal exposure to proinflammatory cytokines is a risk factor for the development of bronchopulmonary dysplasia; (2) the injury responsible for bronchopulmonary dysplasia in a subset of neonates may begin before birth.     

The "interleukin 1 receptor antagonist" is a partial agonist of prostaglandin synthesis by human decidual cells

In many systems the interleukin-1 receptor antagonist opposes the effects of interleukin-1 beta. We considered that it might block interleukin-1 beta-stimulated prostaglandin production from human decidual cells. Very high levels of interleukin-1 receptor antagonist (> 1000 pg/ml) had limited inhibitory effects on IL-1 beta-stimulated PGE2 synthesis, and lower levels of antagonist (< 1000 pg/ml) increased the effects of IL-1 beta. Low concentrations of the antagonist alone (1-100 pg/ml) increased basal PGE2 production, whereas higher levels (10-100 ng/ml) had less effect. It seems, therefore, that in human decidua the "antagonist" is more accurately described as a partial agonist. It has been suggested that the IL-1 receptor antagonist could be used to inhibit decidual prostaglandin synthesis and thereby prevent preterm labor, but this report shows that caution should be exercised before using the receptor antagonist.     

An increase in fetal plasma cortisol but not dehydroepiandrosterone sulfate is followed by the onset of preterm labor in patients with preterm premature rupture of the membranes

OBJECTIVE: The role of steroid hormones in the control of human parturition has been a subject of debate. Activation of the fetal hypothalamic-pituitary-adrenal axis leading to an increase in plasma cortisol is followed by the onset of parturition in sheep. In contrast, androgens, specifically, dehydroepiandrosterone sulfate, have been implicated in the control of parturition in nonhuman primates. The purpose of this study was to determine the relationship between human fetal plasma cortisol and dehydroepiandrosterone sulfate and the onset of preterm labor in patients with preterm premature rupture of the membranes. STUDY DESIGN: Fetal blood sampling was performed in 51 patients with preterm premature rupture of membranes who were not in labor on admission. Amniotic fluid was cultured for aerobic and anaerobic bacteria and mycoplasmas. Corticosteroids had not been administered before fetal blood sampling. Cortisol and dehydroepiandrosterone sulfate were measured with sensitive and specific immunoassays. Analysis was conducted with nonparametric statistics and survival analysis. RESULTS: (1) Patients who went into spontaneous labor and delivered within 7 days of cordocentesis had a significantly higher median level of fetal plasma cortisol but not of dehydroepiandrosterone sulfate than those delivered after 7 days (for fetal plasma cortisol: median 8.35 [4.7 to 12.4] micrograms/dL vs median 4.75 [3.0 to 10.4] micrograms/dL, P <.0001; for fetal plasma dehydroepiandrosterone sulfate: median 154.4 [8.6 to 333.8] micrograms/dL vs median 194.6 [96.7 to 402.5] micrograms/dL, P =.09). (2) The cordocentesis-to-delivery interval was significantly shorter in patients with a fetal plasma cortisol value of >/=7 micrograms/dL (derived by receiver-operating characteristic curve analysis) than in those with fetal cortisol <7 micrograms/dL (median 49 [4 to 1849] hours vs median 325 [11 to 2590] hours, P <.001). (3) Fetal plasma cortisol, but not maternal cortisol, was an independent predictor of the duration of pregnancy after we adjusted for gestational age and the results of amniotic fluid culture (hazards ratio 2.9, P <.05). (4) There was a significant correlation between fetal plasma cortisol and fetal plasma interleukin-6 (r = 0.3, P <.05). (5) A strong relationship was found between the fetal plasma cortisol/dehydroepiandrosterone sulfate ratio and the interval to delivery (P <.005). CONCLUSION: An elevation in fetal plasma cortisol but not dehydroepiandrosterone sulfate was followed by the onset of spontaneous preterm labor in patients with preterm premature rupture of the membranes.     

Elevated amniotic fluid levels of leukemia inhibitory factor, interleukin 6, and interleukin 8 in intra-amniotic infection

OBJECTIVE: The study's objective was to determine and correlate amniotic fluid levels of leukemia inhibitory factor, interleukin 6, and interleukin 8 in patients with and without intra-amniotic infection. STUDY DESIGN: Amniocentesis was performed on 41 pregnant women with preterm contractions, labor, or premature rupture of membranes. Intra-amniotic infection was defined as the presence of a positive amniotic fluid culture result. Amniotic fluid tests for Gram stain, glucose, leukocyte counts, creatinine level, pH, and specific gravity were performed. Amniotic fluid levels of leukemia inhibitory factor, interleukin 6, and interleukin 8 were measured by an enzyme-linked immunoassay. Unlike in previous reports, cytokines were normalized by amniotic fluid creatinine levels. RESULTS: Fifteen patients had intra-amniotic infection and 26 did not. Amniotic fluid median levels of leukemia inhibitory factor, interleukin 6, and interleukin 8 were significantly higher in pregnant women with intra-amniotic infection than in those without intra-amniotic infection (leukemia inhibitory factor median 3912 pg/mg creatinine, range 0.0-199314, vs 56 pg/mg creatinine, range 0. 0-12148, P =.01; interleukin 6 median 2005 ng/mg creatinine, range 27-4071, vs 990 ng/mg creatinine, range 7.5-3409, P =.005; interleukin 8: median 4933 ng/mg creatinine, range 0.0-55058, vs 61 ng/mg creatinine, range 0.0-2399, P =.005). Amniotic fluid levels of leukemia inhibitory factor, interleukin 6, and interleukin 8 were positively correlated. CONCLUSIONS: The data indicate that leukemia inhibitory factor plays an important role in the pathogenesis of intra-amniotic infection. In addition, significant elevations of and correlations among amniotic fluid levels of leukemia inhibitory factor, interleukin 6, and interleukin 8 suggest that measurements of these cytokines in amniotic fluid may be of diagnostic and prognostic importance.     

No deterioration in insulin sensitivity, but impairment of both pancreatic beta-cell function and glucose sensitivity, in Japanese women with former gestational diabetes mellitus

Recent studies have demonstrated a strong correlation between infection and preterm labor. Preterm delivery is also associated with high levels of cytokines and prostaglandins in amniotic fluid. The purpose of this study was to investigate the effect of tumor necrosis factor-alpha (TNF-alpha) on the levels of cyclooxygenase, prostaglandin E2 production (PGE2), and expression of the PGE2 receptor subtype EP1 in amnion WISH cell culture. Amnion WISH cell cultures were incubated in increasing concentrations of TNF-alpha (0-50 ng/ml). Changes in cyclooxygenase and EP1 receptor proteins were evaluated by Western blot analysis. Changes in EP1 mRNA were evaluated by Northern blot, and culture fluid concentrations of PGE2 were estimated by enzyme immunoassay (EIA). EP1 protein (p<0.01), EP1 mRNA (p<0.05), cyclooxygenase-2 (COX-2) protein (p<0.001), and PGE2 concentrations (p<0.01) all increased with increasing concentrations of TNF-alpha. Changes in COX-1 protein were not observed following TNF-alpha-incubation. The results suggest that TNF-alpha may play a role in infection-induced preterm labor by its pleiotropic ability to simultaneously stimulate COX-2 activity, PGE2 concentrations, and PGE2 EP1 receptor levels in human amnion.     

The neuronal alpha6 subunit forms functional heteromeric acetylcholine receptors in human transfected cells

OBJECTIVE: Our purpose was to create a model for predicting amnionitis and rapid delivery in preterm labor patients by use of amniotic fluid interleukin-6 and clinical parameters. STUDY DESIGN: Amniotic fluid was cultured and analyzed, and a clinical score (incorporating gestational age, amniotic fluid Gram stain, glucose, leukocyte esterase, and maternal serum C-reactive protein) was determined in 111 patients diagnosed with preterm labor. Statistical analysis involved t tests, chi2, logarithmic regression, and multivariate regression analysis (P < or = .05). RESULTS: The incidence of positive amniotic fluid cultures was 8.7% (9 of 103 patients). Patients with positive cultures of the amniotic fluid had a shorter delivery interval (4.8 +/- 7.5 vs 28.9 +/- 25.4 days, P < .001). Patients with elevated amniotic fluid interleukin-6 (> or = 7586 pg/ml) were more likely to have a positive amniotic fluid culture (relative risk = 8.8, 95% confidence interval = 1.6 to 47.4, P < .001) and to be delivered within 2 days (relative risk = 16.8, 95% confidence interval = 4.5 to 62.7, P < .001). Stepwise multivariate regression analysis yielded a model using interleukin-6, cervical dilatation, and gestational age (r2 = 0.63, P < .001) with a specificity of 100% for predicting delivery within 2 days of amniocentesis. CONCLUSIONS: A mathematical model using maternal amniotic fluid interleukin-6 seems to be a useful clinical tool for quantifying the interval to preterm birth for patients in preterm labor.     

Inflammatory cytokine (interleukins 1, 6 and 8 and tumor necrosis factor-alpha) release from cultured human fetal membranes in response to endotoxic lipopolysaccharide mirrors amniotic fluid concentrations

OBJECTIVE: This study was conducted to quantitate and compare the amount of cytokines released from human fetal membranes in response to treatment with bacterial lipopolysaccharide and to compare this with amniotic fluid levels. STUDY DESIGN: Amniochorionic membranes were collected from women undergoing elective repeat cesarean section and showing no signs of infection- or pregnancy-related complications. Membranes were maintained in an organ explant system and stimulated with bacterial lipopolysaccharide for 24 hours. Media samples were collected and stored at -20 degrees C until cytokine levels were assayed by enzyme-linked immunosorbent assay. RESULTS: Enzyme-linked immunosorbent assay results demonstrated that lipopolysaccharide stimulated production of interleukins 1, 6 and 8 and tumor necrosis factor-alpha by the fetal membranes in comparison with the control cultures. A greater release of interleukin-6 and interleukin-8 compared with interleukin-1 and tumor necrosis factor-alpha was noticed. The relationships between cytokine concentrations observed in culture mirror those seen in amniotic fluid. CONCLUSION: Amniochorionic membranes can respond to an infectious process with increased secretion of interleukins 1, 6 and 8 and tumor necrosis factor-alpha. Cytokines produced from both amnion and chorion (interleukin-6 and interleukin-8) are released in greater quantities than those cytokines produced from chorion or amnion alone (interleukin-1 and tumor necrosis factor-alpha). These studies support a major role for amnion in infection-induced preterm labor.     

Coagulation and fibrinolytic responses of human peritoneal fluid and plasma to bacterial peritonitis

Significantly higher (P < 0.05) thrombin-antithrombin III complex levels were found in the abdominal exudate of patients with peritonitis (median 5500 ng/ml) than in that of controls (median 89 ng/ml). In patients, peritoneal fluid concentrations of tissue and urokinase-type plasminogen activator were increased by factors of 65 and 10 respectively (P < 0.05). The concentration of plasminogen activator inhibitor (PAI) 1 was increased by a factor of about 800 (median 395 versus 0.5 ng/ml, P < 0.05). Despite markedly raised concentrations of PAI, peritoneal fluid displayed fibrinolytic activity as demonstrated by significantly increased (P < 0.05) concentrations of plasmin-alpha 2-antiplasmin complex (median 10,952 versus 57 ng/ml) and fibrin degradation products (median 40,360 versus 126 ng/ml). There was no correlation between plasma and peritoneal fluid concentrations. Intraabdominal coagulation and fibrinolysis are stimulated in the abdominal cavity of patients with bacterial peritonitis.     

Plasma endotoxin and cytokine levels in neutropenic and non-neutropenic bacteremic patients

Plasma endotoxin, tumor necrosis factor-alpha (TNF-alpha), interleukin 1 beta (IL-1 beta), interleukin 1 receptor antagonist (IL-1ra), and interleukin 6 (IL-6) concentrations in 69 bacteremic patients were compared with those in 54 nonbacteremic patients suffering from suspected bacterial infections. Only three (11%) of the 27 patients with gram-negative bacteremia showed detectable levels of endotoxin. TNF-alpha was detected in 6% of the bacteremic patients and in none of the nonbacteremic patients. Median IL-6 levels were significantly higher in bacteremic than in nonbacteremic patients (55 vs. 0 pg/ml, p = 0.0008). IL-6 concentrations were similar in neutropenic and non-neutropenic bacteremic patients (median 55 vs. 74 pg/ml). In contrast, neutropenic bacteremic patients had significantly lower concentrations of IL-1ra than non-neutropenic bacteremic patients (250 vs. 1,950 pg/ml, p < 0.0001). Patients with fatal bacteremia had significantly higher concentrations of IL-6 and IL-1ra than the survivors (median, 450 vs. 40, p = 0.012 and 7,600 vs. 420 pg/ml, p = 0.0075, respectively). Determinations of endotoxin or TNF-alpha in patients with suspected bacteremia failed to offer clinically relevant data on the prognosis of these patients. IL-6 levels correlated with both the presence of bacteremia and the risk of death. Granulocytopenic patients with bacteremia had lower levels of circulating IL-1ra than patients with normal granulocyte counts, and these levels correlated with poor outcome.     

Placental histopathology in premature rupture of membranes. Its relationship with microbiological findings, maternal, and neonatal outcome

BACKGROUND: There is a close relationship between premature membrane rupture, bacterial infections and premature labor. AIM: To study placental histological changes in patients with preterm membrane rupture. To establish a relationship between pathological findings, amniotic fluid and lower genital tract microbiological studies, maternal and neonatal outcome. PATIENTS AND METHODS: Patients with premature membrane rupture of membranes between 24 and 34 weeks of gestation participated in this study. On admission, patients had no evidence of clinical chorioamnionitis, labor or fetal distress. Microbiological studies of the amniotic fluid and cervicovaginal secretions were performed and the placenta was sent for pathological study. RESULTS: Seventy one placentas were available for the study. The main pathological findings were acute chorioamnionitis in 58%, trophoblastic proliferation in 38%, funisitis in 37%, villitis in 16%, fetal vascular lesions in 14% and no findings in 17%. Microbial invasion of amniotic cavity was present in 89% of acute chorioamnionitis. Sixty one percent of trophoblastic proliferation and all fetal vascular lesions were associated with negative amniotic and cervical cultures. Newborns with acute funisitis had a higher frequency of neonatal death (29%), severe asphyxia (42%) and neonatal infections (29%). CONCLUSIONS: Acute chorioamnionitis is the most frequent finding in patients with preterm membrane rupture and microbial invasion of amniotic cavity. In the absence of intra amniotic infection, proliferation of the trophoblast and the presence of fetal vascular lesions predominate. Acute funisitis is strongly associated with adverse fetal outcome.     

A comparison of rapid amniotic fluid markers in the prediction of microbial invasion of the uterine cavity and preterm delivery

OBJECTIVE: The purpose of this study was to evaluate amniotic fluid lactate dehydrogenase level in comparison with other rapid markers in prediction of microbial invasion of the uterine cavity and preterm delivery < or = 36 hours after amniocentesis. STUDY DESIGN: One hundred thirty-one women in preterm labor with intact membranes underwent transabdominal amniocentesis. Amniotic fluid was analyzed for leukocyte count, glucose level, lactate dehydrogenase level, and Gram stain. Cultures for aerobes, anaerobes, and Mycoplasma sp. were performed. Amniocentesis-to-delivery interval was calculated. The study group was divided and the findings compared according to amniotic fluid culture results and according to amniocentesis-to-delivery interval. Sensitivity, specificity, and positive and negative predictive value were calculated for lactate dehydrogenase, leukocyte count, glucose, and Gram stain in the prediction of positive amniotic fluid culture and preterm delivery < or = 36 hours after amniocentesis. Receiver-operator characteristic curve analysis, logistic regression analysis, t tests, and nonparametric tests were used. RESULTS: The prevalence of positive amniotic fluid cultures was 12% (16 of 131). The median lactate dehydrogenase level (1084 U/L) was significantly greater for women with a positive amniotic fluid culture than for those with a negative culture (median lactate dehydrogenase level 194 U/L; p < 0.0002). The critical values calculated for optimal performance in prediction of a positive amniotic fluid culture were a lactate dehydrogenase level > or = 419 U/L, leukocyte count > or = 50 cells/mm3 (50 x 10(6)/L) and glucose < or = 17 mg/dl (0.94 mmol/L). Lactate dehydrogenase, leukocyte count, glucose, and Gram stain were equally sensitive and specific in prediction of a positive amniotic fluid culture. Thirty-nine women (29.8%) gave birth < or = 36 hours after amniocentesis. The median lactate dehydrogenase level (414 U/L) was significantly greater among women giving birth < or = 36 hours after amniocentesis than among women giving birth > 36 hours after amniocentesis (median lactate dehydrogenase, 173 U/L; p < 0.001). Critical values of lactate dehydrogenase > or = 225 U/L, leukocyte count > or = 10 cells/mm3 (10 x 10(6)/L) and glucose < or = 34 mg/dl (1.9 mmol/L) were selected for optimal performance in prediction of amniocentesis-to-delivery interval < or = 36 hours. Lactate dehydrogenase level had the best sensitivity (74%) in prediction of delivery < or = 36 hours after amniocentesis in contrast to leukocyte count (49%), glucose (62%), and positive Gram stain (26%). Amniotic fluid lactate dehydrogenase values > or = 225 U/L were associated with a fivefold greater risk for delivery < or = 36 hours after amniocentesis (odds ratio 5.46, 95% confidence interval 2.00 to 14.87; p = 0.0006). CONCLUSION: Amniotic fluid lactate dehydrogenase level has diagnostic value in prediction of a positive amniotic fluid culture and delivery < or = 36 hours after amniocentesis. Lactate dehydrogenase is a readily available, inexpensive, rapid amniotic fluid marker that can be measured in any hospital laboratory.     

Activin A and inhibin B in extra-embryonic coelomic and amniotic fluids, and maternal serum in early pregnancy

Activin A and inhibin B levels were measured, using a two-site enzyme immunoassay, in extra-embryonic coelomic fluid, amniotic fluid and maternal serum samples retrieved from 23 healthy pregnant women, at 8 (n=8), 9 (n=8), and 10 (n=7) weeks of gestation. Dimeric activin A and inhibin B were measurable in all samples. Median (+/-SEM) activin A concentrations in coelomic fluid (0.98+/-0.34 ng/ml) were significantly higher than in maternal serum (0.68+/-0.05 ng/ml) and in amniotic fluid (0.09+/-0.04 ng/ml) (P<0.05). Maternal serum activin A levels were significantly higher than amniotic fluid concentrations. Median (+/-SEM) inhibin B concentrations in coelomic fluid (24.32+/-6.02 pg/ml) were significantly higher than in maternal serum (5.94+/-0.97 pg/ml) and in amniotic fluid (6.31+/-1.53 pg/ml) (P<0.05), while no significant difference between maternal serum levels and amniotic fluid concentrations was found. No significant difference in activin A and inhibin B levels in extra-coelomic fluid, amniotic fluid, and maternal serum throughout the 3 weeks of pregnancy was found. The present study showed that coelomic fluid is an important reservoir of activin A and inhibin B, supporting the hypothesis that the extra-embryonic coelom may have a secretory role during the first 11 weeks of gestation.     

Postnatal changes of leptin levels in full-term and preterm neonates: their relation to intrauterine growth, gender and testosterone

The present study was carried out to investigate leptin levels in arterial and venous cord serum and in amniotic fluid in full-term infants at birth and on the 5th postnatal day to define the relationship of leptin to intrauterine growth rate, gender and early postnatal life. The relation of weight gain to serum leptin levels in male preterm infants was determined measuring leptin concentration weekly in the first 5 postnatal weeks. Testosterone levels were determined simultaneously to explore a possible relationship between leptin and testosterone concentrations. Fifty-three term newborn infants with mean birth weight and gestational age of 3,419 g (range 2,150-4,480) and 38.9 weeks (range 36-41) and 19 preterm male infants (mean birth weight and gestational age were 1,416 g (770-1,800) and 30.2 weeks (26-35) were enrolled into the study. Leptin and testosterone levels were determined by radioimmunoassay. It was demonstrated that serum leptin levels were markedly elevated in the cord blood without discernible arteriovenous differences. Cord blood leptin was found to correlate with birth weight (r = 0.40, p < 0.002), weight to length ratio (r = 0.40, p < 0.002) and body mass index (r = 0.35, p < 0.005). It was significantly lower in boys as opposed to girls (p < 0.01) and there was an apparent fall by the 5th postnatal day (p < 0.001). Amniotic fluid contained leptin in much less concentration than cord blood and it proved to be independent of intrauterine growth or gender. Serum leptin concentration in preterm infants at 1 week of age was significantly lower compared with term infants (p < 0.002) and it increased progressively with age (p < 0.01). An inverse relationship was found between leptin and testosterone level (r = -0.358, p < 0.01) and a positive correlation between leptin level and weight/height ratio (r = 0.674, p < 0.01). It is concluded that leptin derived either from placenta or fetal adipose tissue may be involved in regulating fetal growth and development and it may be related to energy intake, storage and expenditure. In preterm male infants serum leptin concentration increases with postnatal weight and testosterone may suppress leptin synthesis.     

Maternal plasma hypo-osmolality: effects on spontaneous and stimulated ovine fetal swallowing

Fetal swallowing is a major route of amniotic fluid resorption, and thus swallowing activity may alter amniotic fluid volume. Near-term ovine fetal swallowing increases in response to plasma and/or cerebrospinal fluid hypertonicity. As maternal hydration status alters amniotic fluid volume, we hypothesized that maternal plasma hypotonicity may alter fetal swallowing activity. Pregnant ewes (130 +/- 1 d; n = 6) were chronically prepared with maternal and fetal vascular catheters, a fetal esophageal flow probe, and fetal thyrohyoid and nuchal and thoracic esophagus electromyogram electrodes. Spontaneous fetal swallowing and hypertonic saline thresholds for stimulated swallowing were determined prior to and following maternal hypotonicity induced with water loading and intravenous DDAVP (arginine vasopressin V2 agonist). Fetal swallowing thresholds were determined with intracarotid injections (0.15 ml/kg) of increasing sodium chloride concentrations (0.15-1.2 M) at 2-min intervals. Maternal DDAVP infusion significantly decreased mean (+/-SEM) maternal and fetal plasma osmolalities (298 +/- 2-284 +/- 3; 295 +/- 2-278 +/- 3 mOsm/kg, respectively) and sodium concentrations (147.3 +/- 0.4-137.5 +/- 0.9; 142.7 +/- 0.8-133.5 +/- 1.0 mEq/l, respectively), suppressed spontaneous swallowing activity and volume (1.1 +/- 0.2-0.6 +/- 0.1 swallows/min; 0.7 +/- 0.2-0.5 +/- 0.1 ml/min, respectively) and significantly increased the osmotic threshold for swallowing stimulation (0.77 +/- 0.08-1.03 +/- 0.09 M NaCl). We conclude that: (1) maternal, and thus fetal, plasma hypotonicity results in suppression of spontaneous fetal swallowing activity and a decrease in volume swallowed, suggesting that spontaneous fetal ingestive behavior results, in part, from tonic dipsogenic stimulation, and (2) under hypotonic conditions, the intracarotid NaCl injection concentration for swallowing stimulation increases. These results suggest that the reset (lower) maternal plasma osmolality during human pregnancy may serve to minimize fetal ingestive and perhaps arginine vasopressin-mediated antidiuretic responses to acute maternal hypertonicity.