Maternal genital colonization with Ureaplasma urealyticum promotes preterm delivery: association of the respiratory colonization of premature infants with chronic lung disease and increased mortality

[Clinical characteristics of Ureaplasma urealyticum infection and colonization in extremely preterm infants]

OBJECTIVES

To investigate the clinical characteristics of Ureaplasma urealyticum (UU) infection and colonization in extremely preterm infants and its impact on the incidence of bronchopulmonary dysplasia (BPD).

METHODS

A retrospective analysis was conducted on 258 extremely preterm infants who were admitted to the Department of Neonatology, Shenzhen Maternity and Child Healthcare Hospital, from September 2018 to September 2022. According to the results of UU nucleic acid testing and the evaluation criteria for UU infection and colonization, the subjects were divided into three groups: UU-negative group (155 infants), UU infection group (70 infants), and UU colonization group (33 infants). The three groups were compared in terms of general information and primary and secondary clinical outcomes.

RESULTS

Compared with the UU-negative group, the UU infection group had significant increases in the incidence rate of BPD, total oxygen supply time, and the length of hospital stay (P<0.05), while there were no significant differences in the incidence rates of BPD and moderate/severe BPD between the UU colonization group and the UU-negative group (P>0.05).

CONCLUSIONS

The impact of UU on the incidence of BPD in extremely preterm infants is associated with the pathogenic state of UU (i.e., infection or colonization), and there are significant increases in the incidence rate of BPD, total oxygen supply time, and the length of hospital stay in extremely preterm infants with UU infection. UU colonization is not associated with the incidence of BPD and moderate/severe BPD in extremely preterm infants.

Azithromycin for Eradication of Ureaplasma and Prevention of Bronchopulmonary Dysplasia in Preterm Neonates in the Neonatal Intensive Care Unit

Azithromycin has been explored as a treatment option for eradication of Ureaplasma and prevention of bronchopulmonary dysplasia (BPD) in preterm neonates. However, there is debate about the need for eradication of Ureaplasma and whether azithromycin is safe and efficacious for this indication. This literature review provides an overview of the evidence for use of azithromycin for eradication of Ureaplasma and prevention of BPD, including dosing and duration of azithromycin used in these studies. The literature search included articles published in the English language in Medline and PubMed from 1946 to January 2022. Relevant citations within identified articles were also reviewed. A total of 9 studies representing 388 neonates were included. The percentage of neonates that tested positive for Ureaplasma in these studies ranged from 18.6% to 57.1%. Azithromycin was initiated at <3 days of life in 8 studies (88.9%). Dosing was variable and ranged from 5 to 20 mg/kg/dose administered once daily, and the duration of treatment ranged from 1 to 35 days. Most studies used intravenous azithromycin. Overall, azithromycin was more efficacious than placebo at Ureaplasma eradication; however, most of these studies did not find a difference in the incidence of BPD between patients receiving azithromycin versus placebo. No adverse effects, specifically pyloric stenosis or QT interval prolongation, were noted in these studies.

Adverse pregnancy and birth outcomes associated with Mycoplasma hominis, Ureaplasma urealyticum and Ureaplasma parvum: a systematic review and meta-analysis

OBJECTIVES

Mycoplasma hominis, Ureaplasma urealyticum and Ureaplasma parvum (genital mycoplasmas) commonly colonise the urogenital tract in pregnant women. This systematic review aims to investigate their role in adverse pregnancy and birth outcomes, alone or in combination with bacterial vaginosis (BV).

METHODS

We searched Embase, Medline and CINAHL databases from January 1971 to February 2021. Eligible studies tested for any of the three genital mycoplasmas during pregnancy and reported on the primary outcome, preterm birth (PTB) and/or secondary outcomes low birth weight (LBW), premature rupture of membranes (PROM), spontaneous abortion (SA) and/or perinatal or neonatal death (PND).Two reviewers independently screened titles and abstracts, read potentially eligible full texts and extracted data. Two reviewers independently assessed risks of bias using published checklists. Random effects meta-analysis was used to estimate summary ORs (with 95% CIs and prediction intervals). Multivariable and stratified analyses were synthesised descriptively.

RESULTS

Of 57/1194 included studies, 39 were from high-income countries. In meta-analysis of unadjusted ORs, M. hominis was associated with PTB (OR 1.87, 95% CI 1.49 to 2.34), PROM, LBW and PND but not SA. U. urealyticum was associated with PTB (OR 1.84, 95% CI 1.34 to 2.55), PROM, LBW, SA and PND. U. parvum was associated with PTB (1.60, 95% CI 1.12 to 2.30), PROM and SA. Nine of 57 studies reported any multivariable analysis. In two studies, analyses stratified by BV status showed that M. hominis and U. parvum were more strongly associated with PTB in the presence than in the absence of BV. The most frequent source of bias was a failure to control for confounding.

CONCLUSIONS

The currently available literature does not allow conclusions about the role of mycoplasmas in adverse pregnancy and birth outcomes, alone or with coexisting BV. Future studies that consider genital mycoplasmas in the context of the vaginal microbiome are needed.

PROSPERO REGISTRATION NUMBER

CRD42016050962.

Prevalence and Load of Cervical Ureaplasma Species With Respect to Intra-amniotic Complications in Women With Preterm Prelabor Rupture of Membranes Before 34 weeks

Objectives: To determine the prevalence and load of Ureaplasma spp. DNA in the cervical fluid of women with singleton pregnancies complicated by preterm prelabor rupture of membranes (PPROM) with respect to intra-amniotic infection, sterile intra-amniotic inflammation, and colonization of the amniotic fluid.

Methods: A total of 217 women with PPROM between gestational ages 24 + 0 and 33 + 6 weeks were included in this study. Paired amniotic and cervical fluid samples were collected at the time of admission via transabdominal amniocentesis and using a Dacron polyester swab, respectively. Microbial invasion of the amniotic cavity was diagnosed using a combination of culture and molecular biology methods. Intra-amniotic inflammation was determined based on the concentration of interleukin-6 in the amniotic fluid. Based on the presence or absence of these conditions, the women were stratified into the following subgroups: intra-amniotic infection (with both), sterile intra-amniotic inflammation (with inflammation only), colonization (with microorganisms only), and negative amniotic fluid (without either). The Ureaplasma spp. DNA load in the cervical fluid was assessed using PCR.

Results:Ureaplasma spp. DNA in the cervical fluid was found in 61% (133/217) of the women. Women with negative amniotic had similar prevalence of Ureaplasma spp. DNA in cervical fluid (55%) to those with sterile intra-amniotic inflammation (54%) but lower than those with intra-amniotic infection (73%) and colonization (86%; p < 0.0001). Women with negative amniotic fluid had a lower load of Ureaplasma spp. DNA in their cervical fluid (median: 4.7 × 10³ copies of DNA/ml) than those with intra-amniotic infection (median: 2.8 × 10⁵ copies DNA/ml), sterile intra-amniotic inflammation (median: 5.3 × 10⁴ copies DNA/ml), and colonization (median: 1.2 × 10⁵ copies DNA/mL; p < 0.0001).

Conclusion: In conclusion, in PPROM at <34 weeks, the presence of intra-amniotic infection, sterile intra-amniotic inflammation, or colonization of the amniotic fluid was associated with a higher prevalence and/or load of Ureaplasma spp. DNA in the cervical fluid than the absence of intra-amniotic complications.

Evaluation of the real-time fluorescence loop-mediated isothermal amplification assay for the detection of Ureaplasma urealyticum

Ureaplasma urealyticum (UU) is commonly present in human reproductive tract, which frequently leads to genital tract infection. Hence, there is an urgent need to develop a rapid detection method for UU. In our study, a real-time fluorescence loop-mediated isothermal amplification (LAMP) assay was developed and evaluated for the detection of UU. Two primers were specifically designed based on the highly conserved regions of ureaseB genes. The reaction was carried out for 60 min in a constant temperature system using Bst DNA polymerase, and the process was monitored by real-time fluorescence signal, while polymerase chain reaction (PCR) was performed simultaneously. In real-time fluorescence LAMP reaction system, positive result was only obtained for UU among 9 bacterial strains, with detection sensitivity of 42 pg/μL (4.2 × 10⁵ CFU/mL), and all 16 clinical samples of UU could be detected. In conclusion, real-time fluorescence LAMP is a simple, sensitive, specific and effective method compared with conventional PCR, which shows great promise in the rapid detection of UU.

Pathophysiological and molecular considerations of viral and bacterial infections during maternal-fetal and -neonatal interactions of SARS-CoV-2, Zika, and Mycoplasma infectious diseases

During pregnancy, a series of physiological changes are determined at the molecular, cellular and macroscopic level that make the mother and fetus more susceptible to certain viral and bacterial infections, especially the infections in this and the companion review. Particular situations increase susceptibility to infection in neonates. The enhanced susceptibility to certain infections increases the risk of developing particular diseases that can progress to become morbidly severe. For example, during the current pandemic caused by the SARS-CoV-2 virus, epidemiological studies have established that pregnant women with COVID-19 disease are more likely to be hospitalized. However, the risk for intensive care unit admission and mechanical ventilation is not increased compared with nonpregnant women. Although much remains unknown with this particular infection, the elevated risk of progression during pregnancy towards more severe manifestations of COVID-19 disease is not associated with an increased risk of death. In addition, the epidemiological data available in neonates suggest that their risk of acquiring COVID-19 is low compared with infants (<12 months of age). However, they might be at higher risk for progression to severe COVID-19 disease compared with older children. The data on clinical presentation and disease severity among neonates are limited and based on case reports and small case series. It is well documented the importance of the Zika virus infection as the main cause of several congenital anomalies and birth defects such as microcephaly, and also adverse pregnancy outcomes. Mycoplasma infections also increase adverse pregnancy outcomes. This review will focus on the molecular, pathophysiological and biophysical characteristics of the mother/placental-fetal/neonatal interactions and the possible mechanisms of these pathogens (SARS-CoV-2, ZIKV, and Mycoplasmas) for promoting disease at this level.

The Zonulin-transgenic mouse displays behavioral alterations ameliorated via depletion of the gut microbiota

The gut-brain axis hypothesis suggests that interactions in the intestinal milieu are critically involved in regulating brain function. Several studies point to a gut-microbiota-brain connection linking an impaired intestinal barrier and altered gut microbiota composition to neurological disorders involving neuroinflammation. Increased gut permeability allows luminal antigens to cross the gut epithelium, and via the blood stream and an impaired blood-brain barrier (BBB) enters the brain impacting its function. Pre-haptoglobin 2 (pHP2), the precursor protein to mature HP2, is the first characterized member of the zonulin family of structurally related proteins. pHP 2 has been identified in humans as the thus far only endogenous regulator of epithelial and endothelial tight junctions (TJs). We have leveraged the Zonulin-transgenic mouse (Ztm) that expresses a murine pHP2 (zonulin) to determine the role of increased gut permeability and its synergy with a dysbiotic intestinal microbiota on brain function and behavior. Here we show that Ztm mice display sex-dependent behavioral abnormalities accompanied by altered gene expression of BBB TJs and increased expression of brain inflammatory genes. Antibiotic depletion of the gut microbiota in Ztm mice downregulated brain inflammatory markers ameliorating some anxiety-like behavior. Overall, we show that zonulin-dependent alterations in gut permeability and dysbiosis of the gut microbiota are associated with an altered BBB integrity, neuroinflammation, and behavioral changes that are partially ameliorated by microbiota depletion. Our results suggest the Ztm model as a tool for the study of the cross-talk between the microbiome/gut and the brain in the context of neurobehavioral/neuroinflammatory disorders.

Ureasplasma and Its Role in Adverse Perinatal Outcomes: A Review

Human Ureaplasma species are the most common microbes found in amniotic fluid and in the placenta after preterm birth, and have previously been correlated with chorioamnionitis, preterm labor, and bronchopulmonary dysplasia, among other adverse birth and neonatal outcomes. Although these correlations exist, there still remains little explanation as to whether Ureaplasma plays a pathogenic role in the development of neonatal disease. In addition, Ureaplasma species are not usually identified on routine culture as they require special culture methods because of their fastidious growth requirements. Treatment of Ureaplasma with macrolides has been shown to effectively eradicate the bacteria in pregnant women and infants. However, it is unclear whether this leads to improved neonatal morbidity and mortality, or whether these generally represent commensal organisms. This review will synthesize the current perspectives about the proposed mechanisms of pathogenicity of Ureaplasma bacteria, its links to poor neonatal outcomes, and the role of screening and treatment in current clinical practice.

Effect of probiotics on vaginal Ureaplasma parvum in women suffering from unexplained infertility

RESEARCH QUESTION

Does oral probiotic supplementation influence the relative abundance of different vaginal microbiota in women experiencing infertility?

DESIGN

A prospective, monocentric randomized controlled trial. To study the influence of probiotics on infertility, 80 patients with primary or secondary infertility were included. Patients were assigned to either a probiotic treatment or a control group. Participants in the treatment group (n = 40) took one sachet (2 g) a day of a defined probiotic supplement limiting Lactobacillus strains. Patients in the control group did not receive any additional probiotic supplements. Vaginal samples were taken on day 20 of the menstrual cycle and 4 weeks later, on day 20, of the consecutive cycle. Subsequently, 16s rRNA gene analysis of the vaginal samples was conducted.

RESULTS

After the intervention phase, no effects on alpha diversity resulting from treatment could be observed. The between sample diversity of different women (beta diversity) at baseline had no effects of age, treatment group or body mass index. Primary or secondary sterility, however, had a significant effect on community. Three clusters (Lactobacillus crispatus, Lactobacillus iners and Lactobacillus gasseri) were identified as the leading representatives. Furthermore, patients treated with probiotics showed limited growth of Ureaplasma parvum compared with the control group (P = 0.021).

CONCLUSIONS

This study points to a possible protective effect of probiotic supplements on the vaginal microbiota. It is tempting to speculate that this effect assists in containing the growth of non-beneficial bacteria and helps to prevent or cure a dysbiotic vaginal flora.

Maternal Vaginal Ureaplasma spp. Colonization in Early Pregnancy Is Associated with Adverse Short- and Long-Term Outcome of Very Preterm Infants

Vaginal colonization with Ureaplasma (U.) spp. has been shown to be associated with adverse pregnancy outcome; however, data on neonatal outcome are scarce. The aim of the study was to investigate whether maternal vaginal colonization with U. spp. in early pregnancy represents a risk factor for adverse short- or long-term outcome of preterm infants. Previously, 4330 pregnant women were enrolled in an observational multicenter study, analyzing the association between vaginal U. spp. colonization and spontaneous preterm birth. U. spp. colonization was diagnosed via PCR analysis from vaginal swabs. For this study, data on short-term outcome were collected from medical records and long-term outcome was examined via Bayley Scales of Infant Development at 24 months adjusted age. Two-hundred-and-thirty-eight children were born <33 weeks gestational age. After exclusion due to asphyxia, malformations, and lost-to-follow-up, data on short-term and long-term outcome were available from 222 and 92 infants, respectively. Results show a significant association between vaginal U. spp. colonization and severe intraventricular hemorrhage (10.4% vs. 2.6%, p = 0.03), retinopathy of prematurity (21.7% vs. 10.3%, p = 0.03), and adverse psychomotor outcome (24.3% vs. 1.8%, OR 13.154, 95%CI 1.6,110.2, p = 0.005). The data suggest an association between vaginal U. spp. colonization in early pregnancy and adverse short- and long-term outcome of very preterm infants.

Clinical chorioamnionitis at term X: microbiology, clinical signs, placental pathology, and neonatal bacteremia - implications for clinical care

OBJECTIVES

Clinical chorioamnionitis at term is considered the most common infection-related diagnosis in labor and delivery units worldwide. The syndrome affects 5-12% of all term pregnancies and is a leading cause of maternal morbidity and mortality as well as neonatal death and sepsis. The objectives of this study were to determine the (1) amniotic fluid microbiology using cultivation and molecular microbiologic techniques; (2) diagnostic accuracy of the clinical criteria used to identify patients with intra-amniotic infection; (3) relationship between acute inflammatory lesions of the placenta (maternal and fetal inflammatory responses) and amniotic fluid microbiology and inflammatory markers; and (4) frequency of neonatal bacteremia.

METHODS

This retrospective cross-sectional study included 43 women with the diagnosis of clinical chorioamnionitis at term. The presence of microorganisms in the amniotic cavity was determined through the analysis of amniotic fluid samples by cultivation for aerobes, anaerobes, and genital mycoplasmas. A broad-range polymerase chain reaction coupled with electrospray ionization mass spectrometry was also used to detect bacteria, select viruses, and fungi. Intra-amniotic inflammation was defined as an elevated amniotic fluid interleukin-6 (IL-6) concentration ≥2.6 ng/mL.

RESULTS

(1) Intra-amniotic infection (defined as the combination of microorganisms detected in amniotic fluid and an elevated IL-6 concentration) was present in 63% (27/43) of cases; (2) the most common microorganisms found in the amniotic fluid samples were Ureaplasma species, followed by Gardnerella vaginalis; (3) sterile intra-amniotic inflammation (elevated IL-6 in amniotic fluid but without detectable microorganisms) was present in 5% (2/43) of cases; (4) 26% of patients with the diagnosis of clinical chorioamnionitis had no evidence of intra-amniotic infection or intra-amniotic inflammation; (5) intra-amniotic infection was more common when the membranes were ruptured than when they were intact (78% [21/27] vs. 38% [6/16]; p=0.01); (6) the traditional criteria for the diagnosis of clinical chorioamnionitis had poor diagnostic performance in identifying proven intra-amniotic infection (overall accuracy, 40-58%); (7) neonatal bacteremia was diagnosed in 4.9% (2/41) of cases; and (8) a fetal inflammatory response defined as the presence of severe acute funisitis was observed in 33% (9/27) of cases.

CONCLUSIONS

Clinical chorioamnionitis at term, a syndrome that can result from intra-amniotic infection, was diagnosed in approximately 63% of cases and sterile intra-amniotic inflammation in 5% of cases. However, a substantial number of patients had no evidence of intra-amniotic infection or intra-amniotic inflammation. Evidence of the fetal inflammatory response syndrome was frequently present, but microorganisms were detected in only 4.9% of cases based on cultures of aerobic and anaerobic bacteria in neonatal blood.

Lethal Neonatal Respiratory Failure by Perinatal Transmission of Ureaplasma Parvum after Maternal PPROM

A primiparous pregnant woman was admitted due to preterm premature rupture of membranes (PPROM) at 27+0 week of gestational age (WGA). Conventional vaginal microbiological analysis had no pathological finding. Management decisions based on national guidelines included antenatal corticoids, tocolytics and antibiotics. Unstoppable efforts of preterm labor in 28+0 WGA and supposed amniotic infection syndrome necessitated emergency cesarean section. The preterm infant underwent NICU therapy, developed an early-onset neonatal sepsis and therapy-refractory pulmonary insufficiency with consecutive right heart failure, resulting in death on the 36^th day of life. Microbiota analyses by 16Sr DNA sequencing was performed from maternal vaginal swabs and from neonatal pharyngeal swabs. Maternal antibiotic treatment resulted in depletion of physiological vaginal colonization with Lactobacillus crispatus. Ureaplasma parvum became the dominant vaginal microorganism at delivery and was detected in high relative abundance in the neonatal specimen. Progressive radiological air-space changes and interstitial pathologies associated with Ureaplasma infection (bronchopulmonary dysplasia type III) were seen early at the 3^rd and distinctly from 14^th day of life. This clearly demonstrates the need of vaginal colonization diagnostics in PPROM patients and awareness of the consecutive risks in the preterm. Vaginal microbiome analysis may allow individualized and targeted maternal and fetal diagnostic, prophylactic and therapeutic strategies to identify, protect and treat the high-risk neonates after PPROM.

Maternal azithromycin therapy for Ureaplasma parvum intraamniotic infection improves fetal hemodynamics in a nonhuman primate model

BACKGROUND

Ureaplasma parvum infection is a prevalent cause of intrauterine infection associated with preterm birth, preterm premature rupture of membranes, fetal inflammatory response syndrome, and adverse postnatal sequelae. Elucidation of diagnostic and treatment strategies for infection-associated preterm labor may improve perinatal and long-term outcomes for these cases.

OBJECTIVE

This study assessed the effect of intraamniotic Ureaplasma infection on fetal hemodynamic and cardiac function and the effect of maternal antibiotic treatment on these outcomes.

STUDY DESIGN

Chronically catheterized pregnant rhesus monkeys were assigned to control (n=6), intraamniotic inoculation with Ureaplasma parvum (107 colony-forming units/mL, n=15), and intraamniotic infection plus azithromycin treatment (12.5 mg/kg twice a day intravenously, n=8) groups. At approximately 135 days' gestation (term=165 days), pulsed and color Doppler ultrasonography was used to obtain measurements of fetal hemodynamics (pulsatility index of umbilical artery, ductus venosus, descending aorta, ductus arteriosus, aortic isthmus, right pulmonary artery, middle cerebral artery and cerebroplacental ratio, and left and right ventricular cardiac outputs) and cardiac function (ratio of peak early vs late transmitral flow velocity [marker of ventricular function], Tei index [myocardial performance index]). These indices were stratified by amniotic fluid proinflammatory mediator levels and cardiac histology.

RESULTS

Umbilical and fetal pulmonary artery vascular impedances were significantly increased in animals from the intraamniotic inoculation with Ureaplasma parvum group (P<.05). Azithromycin treatment restored values to control levels. Amniotic fluid prostaglandin F2 alpha levels were significantly higher in animals with abnormal umbilical artery pulsatility index (>1.1) than in those with normal blood flow (P<.05; Spearman ρ=0.6, P<.05). In the intraamniotic inoculation with Ureaplasma parvum group, left ventricular cardiac output was significantly decreased (P<.001), and more animals had abnormal right-to-left ventricular cardiac output ratios (defined as >1.6, P<.05). Amniotic fluid interleukin-6 concentrations were elevated in cases of abnormal right-to-left ventricular cardiac output ratios compared with those in normal cases (P<.05).

CONCLUSION

Fetal hemodynamic alterations were associated with intraamniotic Ureaplasma infection and ameliorated after maternal antibiotic treatment. Doppler ultrasonographic measurements merit continuing investigation as a diagnostic method to identify fetal cardiovascular and hemodynamic compromise associated with intrauterine infection or inflammation and in the evaluation of therapeutic interventions or clinical management of preterm labor.

Different degrees of maternal Ureaplasma colonization and its correlation with bronchopulmonary dysplasia in <32 weeks' preterm infants

BACKGROUND

Ureaplasma spp. is a known risk factor for bronchopulmonary dysplasia (BPD). However, little is known about the effect of different degrees of maternal Ureaplasma colonization and their adverse outcomes. Hence, the aim of this study was to determine the effects of different degrees of maternal Ureaplasma colonization on BPD.

METHODS

A retrospective cohort study of preterm infants delivered at <32 weeks' gestational age (GA) was performed. The infants were divided according to maternal Ureaplasma status as follows: high-colonization (≥104 CCU/ml, UUH), low-colonization (<104 CCU/ml, UUL), and noncolonization (controls). Subgroup analysis according to neonatal respiratory Ureaplasma (n-UU) was also performed to evaluate vertical transmission.

RESULTS

In total, 245 infants were included in this study (UUH = 105, UUL = 47, controls = 93). The rates of preterm labor and histological chorioamnionitis were significantly different. The rate of BPD was significantly high in UUH (P = 0.044). The transmission rate of n-UU colonization was 36% in UUH and 32% in UUL (P = 0.609). The rate of BPD was 78% in n-UU (+) of UUH but 43% in n-UU (-) of UUL (P = 0.027).

CONCLUSIONS

High-degree colonization of maternal Ureaplasma was associated with preterm labor, histological chorioamnionitis, and neonatal BPD. The incidence of BPD was significantly higher in Ureaplasma-colonized infants born to women with high-degree colonization.

Perinatal Ureaplasma Exposure Is Associated With Increased Risk of Late Onset Sepsis and Imbalanced Inflammation in Preterm Infants and May Add to Lung Injury

Background: Controversy remains concerning the impact of Ureaplasma on preterm neonatal morbidity.

Methods: Prospective single-center study in very low birth weight infants <30 weeks' gestation. Cord blood and initial nasopharyngeal swabs were screened for Ureaplasma parvum and U. urealyticum using culture technique and polymerase chain reaction. Neonatal outcomes were followed until death or discharge. Multi-analyte immunoassay provided cord blood levels of inflammatory markers. Using multivariate regression analyses, perinatal Ureaplasma exposure was evaluated as risk factor for the development of bronchopulmonary dysplasia (BPD), other neonatal morbidities until discharge and systemic inflammation at admission.

Results: 40/103 (39%) infants were positive for Ureaplasma in one or both specimens, with U. parvum being the predominant species. While exposure to Ureaplasma alone was not associated with BPD, we found an increased risk of BPD in Ureaplasma-positive infants ventilated ≥5 days (OR 1.64; 95% CI 0.12–22.98; p = 0.009). Presence of Ureaplasma was associated with a 7-fold risk of late onset sepsis (LOS) (95% CI 1.80–27.39; p = 0.014). Moreover, Ureaplasma-positive infants had higher I/T ratios (b 0.39; 95% CI 0.08–0.71; p = 0.014), increased levels of interleukin (IL)-17 (b 0.16; 95% CI 0.02–0.30; p = 0.025) and matrix metalloproteinase 8 (b 0.77; 95% CI 0.10–1.44; p = 0.020), decreased levels of IL-10 (b −0.77; 95% CI −1.58 to −0.01; p = 0.043) and increased ratios of Tumor necrosis factor-α, IL-8, and IL-17 to anti-inflammatory IL-10 (p = 0.003, p = 0.012, p < 0.001).

Conclusions: Positive Ureaplasma screening was not associated with BPD. However, exposure contributed to BPD in infants ventilated ≥5 days and conferred an increased risk of LOS and imbalanced inflammatory cytokine responses.

Correlation between Ureaplasma spp. sub-group 1 and preterm pre-labour rupture of membranes revealed by an eMLST scheme

Ureaplasma spp. is gaining recognition as an important pathogen associated with preterm birth (PTB) and preterm pre-labour rupture of membranes (PPROM). The aim of this study was to investigate the clonality of this organism in maternal/neonatal pairs with PTB or pre-labour rupture of membranes (PROM) or PPROM and the association between sub-groups and PPROM. In total, 50 of 93 maternal/neonatal pairs that were diagnosed with PTB, PROM or PPROM were identified with Ureaplasma spp. colonized in the amniotic fluid or umbilical cord or placenta. All 104 clinical Ureaplasma spp. samples (50, 30, and 24 cultured from amniotic fluid, umbilical cord, and placenta, respectively) were included for analysis of the genetic lineages using the eMLST scheme. A total of 34 eSTs were revealed, with two predominant eSTs (eST16 and eST41). Interestingly, six maternal/neonatal pairs displayed eST differences in the above three specimen sources. In addition, phylogenetic analysis showed two genetically significant distant clusters, and cluster I included the most clinical strains. Interestingly, there was a significant difference in the prevalence of sub-group 1 of cluster II between women with PPROM and those with PROM. In conclusion, the distribution of cluster I was predominately higher than that of cluster II in maternal/neonatal pairs. In addition, sub-group 1 was prone to associated PPROM through the specific epidemic clonal lineages.

Optimum Detection of Ureaplasma in Premature Infants

BACKGROUND

Ureaplasma spp. is a known risk factor for bronchopulmonary dysplasia in premature infants. Emerging research suggests treatment with azithromycin or clarithromycin in the first days of life (DOLs) reduces bronchopulmonary dysplasia in Ureaplasma spp. positive infants. Side effects of these antibiotics make it imperative to optimize reliable noninvasive screening procedures to identify infants who would benefit from treatment.

METHODS

The aim of this study was to determine the best site and time to screen for Ureaplasma spp. in 24- to 34-week premature infants. Oral, nasal, gastric and tracheal cultures were collected and placed immediately in 10B broth media. Polymerase chain reaction verified culture results and identified the Ureaplasma spp.

RESULTS

Cultures yielded a Ureaplasma spp. incidence of 80/168 = 47.6% [95% confidence interval (CI): 40-56]. Nasal cultures had greater sensitivity to detect Ureaplasma spp. than oral cultures (P = 0.008): however, a significant proportion of infants with Ureaplasma spp. would have been missed (12/79 = 15.2%, 95% CI: 8%-25%, P < 0.001) if oral cultures were not obtained. For all sites, the collection at DOL 7-10 were more likely to be positive than the collection at DOL 1-2: however, a significant proportion (5/77 = 6.5%, 95% CI: 2-15, P < 0.001) of infants with Ureaplasma spp. would have been missed if the DOL 1-2 cultures were not obtained.

CONCLUSIONS

For optimal Ureaplasma spp. detection in 24- to 34-week premature infants, cultures need to be taken both early and late in the first 10 DOLs both from nasal and oral secretions.

Ureaplasma urealyticum: the Role as a Pathogen in Women's Health, a Systematic Review

PURPOSE OF REVIEW

To evaluate the role of Ureaplasma urealyticum as a genital pathogen in women's health. Three aspects were analyzed: (1) preterm delivery (PTD); (2) female infertility; and (3) lower genital tract pathology including pelvic inflammatory disease (PID), cervicitis, and genital discomfort (discharge, burning).

RECENT FINDINGS

A systematic review was performed. Searching PUBMED and EMBASE for published articles from January 2003 to September 2017 using the key word "Ureaplasma urealyticum" yielded 1835 manuscripts. These were further screened using defined inclusion criteria: (1) original peer-reviewed observational studies; (2) English language; (3) U. urealyticum was specifically isolated; (4) present "cases"/"exposed" and "controls"/"unexposed" to enable calculating an association between U. urealyticum and the outcome studied. Altogether, 32 studies were included that underwent quality scoring based on methodology, sample size, study population, and method of identification of U. urealyticum. The association of U. urealyticum and PTD was inconsistent between the studies. Eight of the ten prospective studies failed to show an association between U. urealyticum and PTD, yet four of the six case control studies found a positive association. Regarding female infertility and genital discomfort, five of the six studies for each of these topics failed to find an association. Only two studies met the inclusion criteria for cervicitis with conflicting conclusions. Unfortunately, none of the studies met the inclusion criteria for PID. It seems that U. urealyticum has a limited role as a pathogen in female infertility, cervicitis, PID, and genital discomfort. The role as a pathogen in PTD is unclear and future studies are needed to address this issue.

Ureaplasma Species Differentially Modulate Pro- and Anti-Inflammatory Cytokine Responses in Newborn and Adult Human Monocytes Pushing the State Toward Pro-Inflammation

Background:Ureaplasma species have been associated with chorioamnionitis and preterm birth and have been implicated in the pathogenesis of neonatal short and long-term morbidity. However, being mostly commensal bacteria, controversy remains on the pro-inflammatory capacity of Ureaplasma. Discussions are ongoing on the incidence and impact of prenatal, perinatal, and postnatal infection. The present study addressed the impact of Ureaplasma isolates on monocyte-driven inflammation. Methods: Cord blood monocytes of term neonates and adult monocytes, either native or LPS-primed, were cultured with Ureaplasma urealyticum (U. urealyticum) serovar 8 (Uu8) and Ureaplasma parvum serovar 3 (Up3). Using qRT-PCR, cytokine flow cytometry, and multi-analyte immunoassay, we assessed mRNA and protein expression of tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-8, IL-12p40, IL-10, and IL-1 receptor antagonist (IL-1ra) as well as Toll-like receptor (TLR) 2 and TLR4. Results: Uu8 and Up3 induced mRNA expression and protein release of TNF-α, IL-1β and IL-8 in term neonatal and adult monocytes (p < 0.01 and p < 0.05). Intracellular protein expression of TNF-α, IL-1β and IL-8 in Ureaplasma-stimulated cells paralleled those results. Ureaplasma-induced cytokine levels did not significantly differ from LPS-mediated levels except for lower intracellular IL-1β in adult monocytes (Uu8: p < 0.05). Remarkably, ureaplasmas did not induce IL-12p40 response and promoted lower amounts of anti-inflammatory IL-10 and IL-1ra than LPS, provoking a cytokine imbalance more in favor of pro-inflammation (IL-1β/IL-10, IL-8/IL-10 and IL-8/IL-1ra: p < 0.01, vs. LPS). In contrast to LPS, both isolates induced TLR2 mRNA in neonatal and adult cells (p < 0.001 and p < 0.05) and suppressed TLR4 mRNA in adult monocytes (p < 0.05). Upon co-stimulation, Uu8 and Up3 inhibited LPS-induced intracellular IL-1β (p < 0.001 and p < 0.05) and IL-8 in adult monocytes (p < 0.01), while LPS-induced neonatal cytokines were maintained or aggravated (p < 0.05). Conclusion: Our data demonstrate a considerable pro-inflammatory capacity of Ureaplasma isolates in human monocytes. Stimulating pro-inflammatory cytokine responses while hardly inducing immunomodulatory and anti-inflammatory cytokines, ureaplasmas might push monocyte immune responses toward pro-inflammation. Inhibition of LPS-induced cytokines in adult monocytes in contrast to sustained inflammation in term neonatal monocytes indicates a differential modulation of host immune responses to a second stimulus. Modification of TLR2 and TLR4 expression may shape host susceptibility to inflammation.

Mycoplasma/Ureaplasma infection in pregnancy: to screen or not to screen

Mycoplasmata have been linked to pregnancy complications and neonatal risk. While formerly a limited number of species could be discovered by cultures, molecular biology nowadays discovers both lower quantities and more diverse species, making us realize that mycoplasmata are ubiquitous in the vaginal milieu and do not always pose a danger for pregnant women. As the meaning of mycoplasmata in pregnancy is not clear to many clinicians, we summarized the current knowledge about the meaning of different kinds of mycoplasmata in pregnancy and discuss the potential benefits and disadvantages of treatment. Currently, there is no general rule to screen and treat for mycoplasmata in pregnancy. New techniques seem to indicate that Ureaplasma parvum (Up), which now can be distinguished from U. urealyticum (Uu), may pose an increased risk for preterm birth and bronchopulmonary disease in the preterm neonate. Mycoplasma hominis (Mh) is related to early miscarriages and midtrimester abortions, especially in the presence of abnormal vaginal flora. Mycoplasma genitalium (Mg) is now recognized as a sexually transmitted infection (STI) that is involved in the causation of cervicitis, pelvic inflammatory disease (PID) in non-pregnant, and preterm birth and miscarriages in pregnant women, irrespective of the presence of concurrent other STIs, like Chlamydia or gonorrhoea. Proper studies to test for efficacy and improved pregnancy outcome are scarce and inconclusive. Azythromycin is the standard treatment now, although, for Mg, this may not be sufficient. The role of clarithromycin in clinical practice still has to be established. There is a stringent need for new studies based on molecular diagnostic techniques and randomized treatment protocols with promising and safe antimicrobials.

Effect of Mycoplasma hominis and cytomegalovirus infection on pregnancy outcome: A prospective study of 200 Mongolian women and their newborns

In Mongolia, diagnostic tests for the detection of the sexually transmitted mycoplasmas, ureaplasmas, Herpes simplex virus (HSV), and cytomegalovirus (CMV) are currently not routinely used in clinical settings and the frequency of these STIs are enigmatic. The prevalence of these STI pathogens were prospectively evaluated among 200 Mongolian pregnant women and their newborns and correlated with pregnancy outcome. TaqMan PCRs were used to detect bacterial and viral STI pathogens in pre-birth vaginal swabs of the pregnant women and in oral swabs of their newborns. A standardized questionnaire concerning former and present pregnancies was developed and linear regression analysis was used to correlate pathogen detection with pregnancy outcome. Ureaplasmas were the most prevalent of the tested pathogens (positive in 90.5% positive women and 47.5% newborns), followed by mycoplasmas (32.5% and 7.5%), chlamydia (14.5% and 7.5%), trichomonas (8.5% and 4.0%) and gonococcus (0.5% and 0%). CMV was found in 46.5% of the pregnant women and in 10.5% of their newborns, whereas HSV-2 was detected in only two mothers. Multiple regression analyses indicate that colonization of the mothers with U. urealyticum, M. hominis, T. vaginalis or CMV is associated with transmission to newborns and that transmission of M. hominis or CMV from Mongolian pregnant women to offspring is associated with reduced neonatal length and gestational age. Thus, diagnostic tests for their detection should be implemented in the clinical settings in Mongolia.

The Human Ureaplasma Species as Causative Agents of Chorioamnionitis

The human Ureaplasma species are the most frequently isolated microorganisms from the amniotic fluid and placentae of women who deliver preterm and are also associated with spontaneous abortions or miscarriages, neonatal respiratory diseases, and chorioamnionitis. Despite the fact that these microorganisms have been habitually found within placentae of pregnancies with chorioamnionitis, the role of Ureaplasma species as a causative agent has not been satisfactorily explained. There is also controversy surrounding their role in disease, particularly as not all women infected with Ureaplasma spp. develop chorioamnionitis. In this review, we provide evidence that Ureaplasma spp. are associated with diseases of pregnancy and discuss recent findings which demonstrate that Ureaplasma spp. are associated with chorioamnionitis, regardless of gestational age at the time of delivery. Here, we also discuss the proposed major virulence factors of Ureaplasma spp., with a focus on the multiple-banded antigen (MBA), which may facilitate modulation/alteration of the host immune response and potentially explain why only subpopulations of infected women experience adverse pregnancy outcomes. The information presented within this review confirms that Ureaplasma spp. are not simply "innocent bystanders" in disease and highlights that these microorganisms are an often underestimated pathogen of pregnancy.

Ureaplasma infection-mediated release of matrix metalloproteinase-9 and PGP: a novel mechanism of preterm rupture of membranes and chorioamnionitis

BACKGROUND

Premature rupture of membranes and preterm delivery are associated with Ureaplasma infection. We hypothesized that Ureaplasma induced extracellular collagen fragmentation results in production of the tripeptide PGP (proline-glycine-proline), a neutrophil chemoattractant. PGP release from collagen requires matrix metalloproteases (MMP-8/MMP-9) along with a serine protease, prolyl endopeptidase (PE).

METHODS

Ureaplasma culture negative amniotic fluid (indicated preterm birth, n = 8; spontaneous preterm birth, n = 8) and Ureaplasma positive amniotic fluid (spontaneous preterm birth, n = 8) were analyzed by electro-spray ionization-liquid chromatography tandem mass spectrometry for PGP, and for MMP-9 by zymography. PE was evaluated in lysates of U. parvum serovar 3 (Up3) and U. urealyticum serovar 10 (Uu10) by western blotting and activity assay.

RESULTS

PGP and MMP-9 were increased in amniotic fluid from spontaneous preterm birth with positive Ureaplasma cultures, but not with indicated preterm birth or spontaneous preterm birth with negative Ureaplasma cultures. Human neutrophils cocultured with Ureaplasma strains showed increased MMP-9 activity. PE presence and activity were noted with both Ureaplasma strains.

CONCLUSION

Ureaplasma spp. carry the protease necessary for PGP release, and PGP and MMP-9 are increased in amniotic fluid during Ureaplasma infection, suggesting Ureaplasma spp. induced collagen fragmentation contributes to preterm rupture of membranes and neutrophil influx causing chorioamnionitis.

Ureaplasma parvum genotype, combined vaginal colonisation with Candida albicans, and spontaneous preterm birth in an Australian cohort of pregnant women

BACKGROUND

Detection of Ureaplasma, Mycoplasma and Candida spp. in the vagina during pregnancy has previously been associated with preterm birth (PTB). However, the prevalence of these microorganisms and the associated obstetric risks (likely to be population-specific) have not been determined in Australian women; furthermore, in the case of Ureaplasma spp., very few studies have attempted characterisation at the species level and none have examined genotype/serovar status to further refine risk assessment.

METHODS

In order to address these issues we sampled the vaginal fluid of 191 pregnant Australian women at three time points in pregnancy. Culture methods were used for detection of Ureaplasma spp. and Candida spp., and real-time PCR was used for speciation of U. parvum and U. urealyticum, non-albicans Candida spp., Mycoplasma hominis and Mycoplasma genitalium. High-resolution melt PCR was used to genotype U. parvum. Data on various lifestyle factors (including sex during pregnancy and smoking), antimicrobial use and pregnancy outcome were collected on all participants. Chi-square tests were used to assess the association of vaginal microorganisms with PTB.

RESULTS

Detection of Ureaplasma spp. was higher among spontaneous PTB cases, specifically in the presence of U. parvum [77 % preterm (95 % confidence interval (CI) 50-100 %) vs. 36 % term (CI: 29-43 %), p = 0.004], but not U. urealyticum. The association with PTB strengthened when U. parvum genotype SV6 was detected (54 % preterm (CI: 22-85 %) vs. 15 % term (CI: 10-20 %), p = 0.002); this genotype was also present in 80 % (4/5) of cases of PTB <34 weeks gestation. When present with Candida albicans in the same sample, the association with PTB remained strong for both U. parvum [46 % preterm (CI: 15-78 %) vs. 13 % term (CI: 8-18 %), p = 0.005] and U. parvum genotype SV6 [39 % preterm (CI: 8-69 %) vs. 7 % term (CI: 3-11 %), p = 0.003]. With the exception of Candida glabrata, vaginal colonisation status for all organisms was stable throughout pregnancy. Smoking significantly increased the likelihood of detection of all target organisms.

CONCLUSIONS

These data suggest that the presence of different species and serovars of Ureaplasma spp. in the vagina confers an increased risk of spontaneous PTB, findings which may be useful in risk assessment for identifying women who would benefit from antimicrobial treatment.

Neonatal Ureaplasma urealyticum colonization increases pulmonary and cerebral morbidity despite treatment with macrolide antibiotics

OBJECTIVE

To evaluate the influence of Ureaplasma urealyticum (UU) colonization on neonatal pulmonary and cerebral morbidity.

METHODS

Single-center case-control study including all preterm infants with positive UU tracheal colonization between 1990 and 2012. Cases were matched with controls by birth year, gestational age, birth weight, and sex. All cases had received macrolide antibiotics for UU infection starting at the time of first positive culture results from tracheal aspirates. Main outcome parameters included presence and severity of hyaline membrane disease (IRDS), duration of ventilation, bronchopulmonary dysplasia at 36 postmenstrual age and neurological morbidities (seizures, intra-/periventricular hemorrhages-I/PVH, periventricular leukomalacia-PVL).

RESULTS

Of 74 cases identified 8 died and 4 had to be excluded; thus, 62 preterm infants were compared to 62 matched controls. UU was significantly associated with IRDS (79 vs. 61 %, p = 0.015), BPD (24 vs. 6 %, p = 0.003), seizures (23 vs. 5 %, p = 0.002) and I/PVH (45 vs. 24 %, p = 0.028). Cases had longer duration of mechanical ventilation and total duration of invasive and non-invasive ventilation (median 11 vs. 6 days p = 0.006 and 25 vs. 16.5 days p = 0.019, respectively).

CONCLUSION

UU was found to be significantly associated with pulmonary short- and long-term morbidity and mild cerebral impairment despite treatment with macrolide antibiotics.

Prevalence of early-onset neonatal infection among newborns of mothers with bacterial infection or colonization: a systematic review and meta-analysis

BACKGROUND

Although neonatal infections cause a significant proportion of deaths in the first week of life, little is known about the burden of neonatal disease originating from maternal infection or colonization globally. This paper describes the prevalence of vertical transmission--the percentage of newborns with neonatal infection among newborns exposed to maternal infection.

METHODS

We searched Pubmed, Embase, Scopus, Web of Science, Cochrane Library, and WHO Regional Databases for studies of maternal infection, vertical transmission, and neonatal infection. Studies that measured prevalence of bacterial vertical transmission were included. Random effects meta-analyses were used to pool data to calculate prevalence estimates of vertical transmission.

RESULTS

122 studies met the inclusion criteria. Only seven studies (5.7%) were from very high neonatal mortality settings. Considerable heterogeneity existed between studies given the various definitions of infection (lab-confirmed, clinical signs), colonization, and risk factors of infection. The prevalence of early onset neonatal lab-confirmed infection among newborns of mothers with lab-confirmed infection was 17.2% (95%CI 6.5-27.9). The prevalence of neonatal lab-confirmed infection among newborns of colonized mothers was 0% (95% CI 0.0-0.0). The prevalence of neonatal surface colonization among newborns of colonized mothers ranged from 30.9-45.5% depending on the organism. The prevalence of neonatal lab-confirmed infection among newborns of mothers with risk factors (premature rupture of membranes, preterm premature rupture of membranes, prolonged rupture of membranes) ranged from 2.9-19.2% depending on the risk factor.

CONCLUSIONS

The prevalence of early-onset neonatal infection is high among newborns of mothers with infection or risk factors for infection. More high quality studies are needed particularly in high neonatal mortality settings to accurately estimate the prevalence of early-onset infection among newborns at risk.

Ureaplasma species and Mycoplasma hominis in cervical fluid of pregnancies complicated by preterm prelabor rupture of membranes

OBJECTIVE

To evaluate Ureaplasma species and Mycoplasma hominis DNA in the cervical fluid and their association with microbial invasion of the amniotic cavity (MIAC) and/or histological chorioamnionitis (HCA) in pregnancies complicated by preterm prelabor rupture of membranes (PPROM).

STUDY DESIGN

A prospective study of 68 women with singleton pregnancies complicated by PPROM between 24(0/7) and 36(6/7) weeks was conducted. Cervical fluid and amniotic fluid were collected from all women at the time of admission. The Ureaplasma species and Mycoplasma hominis DNA in the cervical fluid were identified using specific real-time PCR.

RESULTS

Ureaplasma species and Mycoplasma hominis DNA were identified in 59% (40/69) of the cervical fluid samples. Women with the presence of Ureaplasma species DNA with and without Mycoplasma hominis DNA in the cervical fluid had a higher rate of MIAC alone [35% (14/40) versus 11% (3/28); p = 0.02] and a higher rate of the presence of both MIAC and HCA [30% (12/40) versus 4% (1/28); p = 0.01] than women without Ureaplasma species and Mycoplasma hominis DNA in the cervical fluid.

CONCLUSIONS

The presence of Ureaplasma species DNA with and without Mycoplasma hominis DNA in the cervical fluid is associated with a higher risk of MIAC or MIAC and HCA together in pregnancies complicated by PPROM.

Animal models of bronchopulmonary dysplasia. The preterm baboon models

Much of the progress in improved neonatal care, particularly management of underdeveloped preterm lungs, has been aided by investigations of multiple animal models, including the neonatal baboon (Papio species). In this article we highlight how the preterm baboon model at both 140 and 125 days gestation (term equivalent 185 days) has advanced our understanding and management of the immature human infant with neonatal lung disease. Not only is the 125-day baboon model extremely relevant to the condition of bronchopulmonary dysplasia but there are also critical neurodevelopmental and other end-organ pathological features associated with this model not fully discussed in this limited forum. We also describe efforts to incorporate perinatal infection into these preterm models, both fetal and neonatal, and particularly associated with Ureaplasma/Mycoplasma organisms. Efforts to rekindle the preterm primate model for future evaluations of therapies such as stem cell replacement, early lung recruitment interventions coupled with noninvasive surfactant and high-frequency nasal ventilation, and surfactant therapy coupled with antioxidant or anti-inflammatory medications, to name a few, should be undertaken.

Comparison between culture and a multiplex quantitative real-time polymerase chain reaction assay detecting Ureaplasma urealyticum and U. parvum

A novel multiplex quantitative real-time polymerase chain reaction (qPCR) for simultaneous detection of U. urealyticum and U. parvum was developed and compared with quantitative culture in Shepard's 10 C medium for ureaplasmas in urethral swabs from 129 men and 66 women, and cervical swabs from 61 women. Using culture as the gold standard, the sensitivity of the qPCR was 96% and 95% for female urethral and cervical swabs, respectively. In male urethral swabs the sensitivity was 89%. The corresponding specificities were 100%, 87% and 99%. The qPCR showed a linear increasing DNA copy number with increasing colour-changing units. Although slightly less sensitive than culture, this multiplex qPCR assay detecting U. urealyticum and U. parvum constitutes a simple and fast alternative to the traditional methods for identification of ureaplasmas and allows simultaneous species differentiation and quantitation in clinical samples. Furthermore, specimens overgrown by other bacteria using the culture method can be evaluated in the qPCR.

Association between pulmonary ureaplasma colonization and bronchopulmonary dysplasia in preterm infants: updated systematic review and meta-analysis

BACKGROUND

Previous meta-analyses have reported a significant association between pulmonary colonization with Ureaplasma and development of bronchopulmonary dysplasia (BPD). However, because few studies reporting oxygen dependency at 36 weeks corrected gestation were previously available, we updated the systematic review and meta-analyses to evaluate the association between presence of pulmonary Ureaplasma and development of BPD.

METHODS

Five databases were searched for articles reporting the incidence of BPD at 36 weeks postmenstrual age (BPD36) and/or BPD at 28 days of life (BPD28) in Ureaplasma colonized and noncolonized groups. Pooled estimates were produced using random effects meta-analysis. Meta-regression was used to assess the influence of difference in gestational age between the Ureaplasma-positive and Ureaplasma-negative groups. The effects of potential sources of heterogeneity were also investigated.

RESULTS

Of 39 studies included, 8 reported BPD36, 22 reported BPD28 and 9 reported both. The quality of studies was assessed as moderate to good. There was a significant association between Ureaplasma and development of BPD36 (odds ratio = 2.22; 95% confidence intervals: 1.42-3.47) and BPD28 (odds ratio = 3.04; 95% confidence intervals: 2.41-3.83). Sample size influenced the odds ratio, but no significant association was noted between BPD28 rates and difference in gestational age between Ureaplasma colonized and noncolonized infants (P = 0.96).

CONCLUSIONS

Pulmonary colonization with Ureaplasma continues to be significantly associated with development of BPD in preterm infants at both 36 weeks postmenstrual age and at 28 days of life. This association at BPD28 persists regardless of difference in gestational age.

Transplacental transfer of Azithromycin and its use for eradicating intra-amniotic ureaplasma infection in a primate model

BACKGROUND

Our goals were to describe azithromycin (AZI) pharmacokinetics in maternal plasma (MP), fetal plasma (FP), and amniotic fluid (AF) following intra-amniotic infection (IAI) with Ureaplasma in pregnant rhesus monkeys and to explore concentration-response relationships.

METHODS

Following intra-amniotic inoculation of Ureaplasma parvum, rhesus monkeys received AZI (12.5 mg/kg every 12 hours intravenously for 10 days; n = 10). Intensive pharmacokinetic sampling of MP, FP, and AF was scheduled following the first (ie, single) dose and the last (ie, multiple) dose. Noncompartmental and pharmacokinetic modeling methods were used.

RESULTS

The AF area under the concentration-time curve at 12 hours was 0.22 µg×h/mL following a single dose and 6.3 µg×h/mL at day 10. MP and AF accumulation indices were 8.4 and 19, respectively. AZI AF half-life following the single dose and multiple dose were 156 and 129 hours, respectively. The median MP:FP ratio in concomitantly drawn samples was 3.2 (range, 1.3-9.6; n = 9). Eradication of U. parvum occurred at 6.6 days, with a 95% effective concentration (EC95) of 39 ng/mL for the maximum AZI AF concentration.

CONCLUSIONS

Our study demonstrates that a maternal multiple-dose AZI regimen is effective in eradicating U. parvum IAI by virtue of intra-amniotic accumulation and suggests that antenatal therapy has the potential to mitigate complications associated with U. parvum infection in pregnancy, such as preterm labor and fetal sequelae.

Ureaplasma urealyticum, Mycoplasma hominis and adverse pregnancy outcomes

PURPOSE OF REVIEW

Mycoplasma hominis and Ureaplasma urealyticum may colonize the human genital tract and have been associated with adverse pregnancy outcomes. Chorioamnionitis, spontaneous preterm labour and preterm premature rupture of membranes are significant contributors to neonatal morbidity and mortality. However, as these bacteria can reside in the normal vaginal flora, there are controversies regarding their true role during pregnancy and thus the need to treat these organisms.

RECENT FINDINGS

We review here the recent data on the epidemiology of mycoplasmas and their clinical role during pregnancy. The association of these organisms with preterm labour has been suggested by many observational studies, but proof of causality remains limited. PCR is an excellent alternative to culture to detect the presence of these organisms, but culture allows antibiotic susceptibility testing. Whether antimicrobial treatment of mycoplasma-colonized pregnant patients can effectively reduce the incidence of adverse pregnancy outcomes warrants further investigations.

SUMMARY

The role of Mycoplasma spp. and U. urealyticum in adverse pregnancy outcomes is increasingly accepted. However, sole presence of these microorganisms in the vaginal flora might be insufficient to cause pathological issues, but their combination with other factors such as bacterial vaginosis or cervical incompetence may be additionally needed to induce preterm birth.

Risk of early-onset neonatal infection with maternal infection or colonization: a global systematic review and meta-analysis

BACKGROUND

Neonatal infections cause a significant proportion of deaths in the first week of life, yet little is known about risk factors and pathways of transmission for early-onset neonatal sepsis globally. We aimed to estimate the risk of neonatal infection (excluding sexually transmitted diseases [STDs] or congenital infections) in the first seven days of life among newborns of mothers with bacterial infection or colonization during the intrapartum period.

METHODS AND FINDINGS

We searched PubMed, Embase, Scopus, Web of Science, Cochrane Library, and the World Health Organization Regional Databases for studies of maternal infection, vertical transmission, and neonatal infection published from January 1, 1960 to March 30, 2013. Studies were included that reported effect measures on the risk of neonatal infection among newborns exposed to maternal infection. Random effects meta-analyses were used to pool data and calculate the odds ratio estimates of risk of infection. Eighty-three studies met the inclusion criteria. Seven studies (8.4%) were from high neonatal mortality settings. Considerable heterogeneity existed between studies given the various definitions of laboratory-confirmed and clinical signs of infection, as well as for colonization and risk factors. The odds ratio for neonatal lab-confirmed infection among newborns of mothers with lab-confirmed infection was 6.6 (95% CI 3.9-11.2). Newborns of mothers with colonization had a 9.4 (95% CI 3.1-28.5) times higher odds of lab-confirmed infection than newborns of non-colonized mothers. Newborns of mothers with risk factors for infection (defined as prelabour rupture of membranes [PROM], preterm <37 weeks PROM, and prolonged ROM) had a 2.3 (95% CI 1.0-5.4) times higher odds of infection than newborns of mothers without risk factors.

CONCLUSIONS

Neonatal infection in the first week of life is associated with maternal infection and colonization. High-quality studies, particularly from settings with high neonatal mortality, are needed to determine whether targeting treatment of maternal infections or colonization, and/or prophylactic antibiotic treatment of newborns of high risk mothers, may prevent a significant proportion of early-onset neonatal sepsis. Please see later in the article for the Editors' Summary.

The prevalence of vaginal microorganisms in pregnant women with preterm labor and preterm birth

Background

To investigate the risk factors for vaginal infections and antimicrobial susceptibilities of vaginal microorganisms among women who experienced preterm birth (PTB), we compared the prevalence of vaginal microorganisms between women who experienced preterm labor (PTL) without preterm delivery and spontaneous PTB.

Methods

Vaginal swab specimens from 126 pregnant women who experienced PTL were tested for group B streptococcus (GBS), Mycoplasma hominis, Mycoplasma genitalium, Ureaplasma urealyticum, Chlamydia trachomatis, Trichomonas vaginalis, Neisseria gonorrhoeae, Treponema pallidum, herpes simplex virus (HSV) I and II, and bacterial vaginosis. A control group of 91 pregnant women was tested for GBS. Antimicrobial susceptibility tests were performed for GBS, M. hominis, and U. urealyticum.

Results

The overall detection rates for each microorganism were: U. urealyticum, 62.7%; M. hominis, 12.7%; GBS, 7.9%; C. trachomatis, 2.4%; and HSV type II, 0.8%. The colonization rate of GBS in control group was 17.6%. The prevalence of GBS, M. hominis, and U. urealyticum in PTL without preterm delivery and spontaneous PTB were 3.8% and 8.7% (relative risk [RR], 2.26), 3.8% and 17.3% (RR, 4.52), and 53.8% and 60.9% (RR, 1.13), respectively, showing no significant difference between the 2 groups. The detection rate of M. hominis by PCR was higher than that by culture method (11.1% vs. 4.0%, P=0.010). The detection rates of U. urealyticum by PCR and culture method were 16.7% and 57.1%, respectively.

Conclusions

There was no significant difference in the prevalence of GBS, M. hominis, and U. urealyticum between the spontaneous PTB and PTL without preterm delivery groups.

Antenatal exposure to Ureaplasma species exacerbates bronchopulmonary dysplasia synergistically with subsequent prolonged mechanical ventilation in preterm infants

INTRODUCTION

The presence of microorganisms in gastric fluid in neonates at birth is postulated to reflect antenatal infection and also to be associated with the development of bronchopulmonary dysplasia (BPD).

RESULTS

A logistic regression analysis, after controlling for other risk factors, indicated that Ureaplasma-positive infants were not at increased risk for moderate/severe BPD (adjusted odds ratio (OR): 2.58, 95% confidence interval (CI): 0.57-6.89, P = 0.12). However, the association between the presence of Ureaplasma species and the risk for moderate/severe BPD increased significantly in infants on mechanical ventilation (MV) ≥2 wk (adjusted OR: 4.17, 95% CI: 1.62-44.1, P = 0.009). An analysis using a lung injury marker indicated that Ureaplasma-positive infants with MV ≥2 wk, but not other infants, showed higher serum KL-6 levels in samples taken from cord blood, and that KL-6 levels increased time-dependently up to 4 wk of age.

DISCUSSION

Antenatal exposure to Ureaplasma species induces lung injury prior to birth and synergistically contributes to the development of BPD in infants requiring prolonged MV (≥2 wk).

METHODS

We recovered gastric fluid specimens from 122 infants with gestational age (GA) <29 wk or birth weight <1,000 g to investigate whether these microorganisms influence respiratory outcome of BPD. A PCR analysis was used to detect urease and 16S ribosomal RNA (rRNA) genes to classify neonates into Ureaplasma-positive or Ureaplasma-negative infants.

Microbiota of the upper and lower genital tract

Our understanding of the bacterial species inhabiting the female genital tract has been limited primarily by our ability to detect them. Early investigations using microscopy and culture-based techniques identified lactobacilli as the predominant members of the vaginal microbiota and suggested that these organisms might serve a protective function at the mucosal surface. Improvements in cultivation techniques and the development of molecular-based detection strategies validated these early findings and enabled us to recognize that the microbiota of the female genital tract is much more complex than previously suspected. Disruption of the vaginal microbial community due to invasion of exogenous organisms or by overgrowth of one or more endogenous species has important health implications for both the mother and newborn.

Clarithromycin in preventing bronchopulmonary dysplasia in Ureaplasma urealyticum-positive preterm infants

OBJECTIVE

To evaluate the efficacy and safety of clarithromycin treatment in preventing bronchopulmonary dysplasia (BPD) in Ureaplasma urealyticum-positive preterm infants.

PATIENTS AND METHODS

Nasopharyngeal swabs for U urealyticum culture were taken from infants with a birth weight between 750 and 1250 g in the first 3 postnatal days. Infants with a positive culture for U urealyticum were randomly assigned to 1 of 2 groups to receive either intravenous clarithromycin or placebo. All the patients were followed at least up to the 36th postmenstrual week.

RESULTS

A total of 224 infants met the eligibility criteria of the study. Seventy-four (33%) infants had a positive culture for U urealyticum in the first 3 day cultures. The rate of BPD development was significantly higher in patients with U urealyticum positivity (15.9% vs 36.4%; P < .01). However, multivariate logistic regression analysis failed to reveal a significant association between the presence of U urealyticum and BPD development (odds ratio: 2.4 [95% confidence interval: 0.9-6.3]; P = .06). Clarithromycin treatment resulted in eradication of U urealyticum in 68.5% of the patients. The incidence of BPD was significantly lower in the clarithromycin group than in the placebo group (2.9% vs 36.4%; P < .001). Multivariate logistic regression analysis confirmed the independent preventive effect of clarithromycin for the development of BPD (odds ratio: 27.2 [95% confidence interval: 2.5-296.1]; P = .007).

CONCLUSIONS

Clarithromycin treatment prevents development of BPD in preterm infants who are born at 750 to 1250 g and colonized with U urealyticum.

The role of Genital Mycoplasmas for the development of urogenital pathology in children

Modern data of the epidemiological aspects and clinical peculiarities of inflammatory urogenital diseases caused by genital mycoplasmas in children are represented. Contemporary methods of laboratory diagnostics and therapy for inflammatory urogenital diseases caused by genital mycoplasmas are described.

Ureaplasma species: role in diseases of prematurity

There is accumulating epidemiologic and experimental evidence that intrauterine or postnatal infection with Ureaplasma species is a significant risk factor for adverse pregnancy outcomes and complications of extreme preterm birth such as bronchopulmonary dysplasia and intraventricular hemorrhage. In a cohort of very low birth weight infants, Ureaplasma spp were detected by culture or polymerase chain reaction in respiratory secretions, blood, or cerebrospinal fluid of almost half of the subjects, suggesting that this organism is the most common pathogen affecting this population. This review summarizes the evidence supporting the hypothesis that Ureaplasma-mediated inflammation in different compartments (intrauterine, lung, blood, or brain) during a common developmental window of vulnerability contributes to preterm labor and lung and brain injury. Appropriate methods for detecting these fastidious organisms and potential strategies to prevent or ameliorate the effects of Ureaplasma infection are discussed.

The use of molecular techniques for bacterial detection in the analysis of gastric aspirates collected from infants on the first day of life

Prospective service evaluation of the utility of molecular methods to analyse neonatal gastric aspirate specimens in a single neonatal unit and associated maternity unit. 43 newborn infants investigated for sepsis with median gestational age of 39 weeks (range 31-41 weeks) and median birth weight 3050 grams (range 1250-4220 g). Gastric aspirates routinely collected within 12h of birth were analysed using conventional and molecular methods for bacterial detection, bacterial DNA load and sequencing to identified bacterial species.

RESULTS

Bacterial DNA loads varied from 0.03 to 1736 pg/microl of DNA extract (1 microl of DNA extract equivalent to 4 microl gastric aspirate). Bacteria were identified in 30/43 (70%) of samples by molecular methods and 10/43 (23.3%) of samples by culture. Cultures were only positive when the bacterial DNA exceeded 4.5 pg/microl of extract. Infants with prolonged rupture of membranes (>24h prior to delivery) had a DNA load on average 23 times higher than those without (95%CI 3.7 to 141; p=0.001). Additional bacteria detected by molecular methods included many species that are fastidious and potentially pathogenic including Leptotrichia spp., Serratia spp., Ureaplasma spp., Veillonella spp., Haemophilus influenzae and Group B Streptococcus. Due to a low rate of adverse outcomes it was not possible to correlate bacterial identifications or DNA load with infant outcome.

CONCLUSIONS

Molecular methods can identify bacteria from a greater proportion of gastric aspirate specimens that conventional culture. Further work is required to establish whether this information can be used to improve infant outcomes.

Ureaplasma: pathogen or passenger in neonatal meningitis?

The significance of Ureaplasma species as pathogens in neonatal meningitis remains contentious. Using an illustrative case of a premature infant with Ureaplasma parvum meningitis, confirmed by cerebrospinal fluid cultures and both specific and 16s rDNA polymerase chain reaction, we discuss the epidemiology of Ureaplasma species, the difficulties involved in diagnosis and establishing pathogenicity, and the challenges in defining appropriate treatment.