Randomised trial of azithromycin to eradicate Ureaplasma in preterm infants

[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.

Association between Ureaplasma urealyticum colonization and bronchopulmonary dysplasia in preterm infants: a systematic review and meta-analysis

Background

Bronchopulmonary dysplasia (BPD) is the most prevalent chronic lung disease in preterm infants. Studies have shown that Ureaplasma urealyticum (UU) infection is linked to its pathogenesis. However, it remains controversial whether UU colonization in preterm infants increases the risk of developing BPD.

Objective

This study aimed to conduct a systematic review and meta-analysis to summarize the correlation between UU and BPD.

Methods

We searched PubMed, Embase, the Cochrane Library, Web of Science, Wanfang Database, Chinese National Knowledge Infrastructure Database, Chinese Science and Technique Journal Database, and the China Biology Medicine disc from their inception to March 15, 2024. We included cohort and case-control studies investigating the association between UU infections and BPD in preterm infants, adhering to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. The Newcastle-Ottawa Scale was used for quality assessment. The outcome was defined as the continued need for oxygen or respiratory support at 28 days after birth (BPD28) or at 36 weeks postmenstrual age (BPD36). Considering the potential publication bias in observational studies, we used a random-effects meta-analysis model, assessed heterogeneity (I2), performed subgroup analyses, evaluated publication bias, and graded the quality of evidence.

Results

The meta-analysis included 36 cohort studies encompassing 5,991 participants. Among these, 20 reported on BPD28, 13 on BPD36, and 3 on both. The results indicated a significant association between UU colonization and BPD28 (odds ratio (OR): 2.26, 95% confidence interval (CI): 1.78-2.85, P < 0.00001, 23 studies, very low certainty of evidence) and BPD36 (OR: 2.13, 95% CI: 1.47-3.07, P < 0.0001, 16 studies, very low certainty of evidence).

Conclusion

There is a correlation between UU colonization and the development of BPD in preterm infants. Future research should prioritize well-designed, large-scale, high-quality randomized controlled trials (RCTs) to comprehensively assess the risk of BPD in neonates following UU infection and to provide stronger evidence for clinical screening and prevention strategies to improve the prognosis of affected newborns.

Systematic Review Registration

https://www.crd.york.ac.uk/, identifier (CRD42024524846).

Azithromycin therapy for prevention of chronic lung disease of prematurity (AZTEC): a multicentre, double-blind, randomised, placebo-controlled trial

BACKGROUND

Systematic reviews have reported conflicting evidence on whether macrolide antibiotics reduce rates of chronic lung disease of prematurity (CLD) in at-risk preterm infants born at less than 30 weeks' gestation, including in those colonised with pulmonary Ureaplasma spp. Since an adequately powered trial has been lacking, we aimed to assess if the macrolide azithromycin improved survival without the development of physiologically defined moderate or severe CLD in preterm infants.

METHODS

AZTEC was a multicentre, double-blind, randomised, placebo-controlled trial conducted in 28 tertiary neonatal intensive care units in the UK. Infants were eligible if they were born at less than 30 weeks' gestation and had received at least 2 h of either non-invasive (continuous positive airway pressure or humidified high flow nasal cannula therapy) or invasive respiratory support (via endotracheal tube) within 72 h of birth. Eligible infants were randomly allocated in a 1:1 ratio using random permuted blocks of four to receive either intravenous azithromycin at 20 mg/kg per day for 3 days followed by 10 mg/kg for 7 days, or to placebo. Allocation was stratified by centre and gestational age at birth (<28 weeks vs ≥28 weeks). Azithromycin and placebo vials were encased in tamper-evident custom cardboard cartons to ensure masking for clinicians, parents, and the research team. The primary outcome was survival without development of physiologically defined moderate or severe CLD at 36 weeks' postmenstrual age. Outcomes and safety were analysed on an intention-to-treat basis (all randomly allocated infants, regardless of any post-randomisation events). The study was registered with ISRCRN (11650227) and is closed.

FINDINGS

Infants were recruited between Oct 9, 2019, and March 22, 2022. 799 (53·1%) of 1505 eligible infants underwent random allocation; three infants were withdrawn, including consent to use their data, leaving 796 infants for analysis. Survival without moderate or severe CLD occurred in 166 (42%) of 394 infants in the intervention group and 179 (45%) of 402 in the placebo group (three-level adjusted OR [aOR] 0·84, 95% CI 0·55-1·29, p=0·43). Pulmonary Ureaplasma spp colonisation did not influence treatment effect. Overall, seven serious adverse events were reported for the azithromycin group (five graded as severe, two as moderate), and six serious adverse events were reported in the placebo group (two severe, two moderate, and two mild), as assessed by the local principal investigators.

INTERPRETATION

Since prophylactic use of azithromycin did not improve survival without development of physiologically-defined CLD, regardless of Ureaplasma spp colonisation, it cannot be recommended in clinical practice.

FUNDING

UK National Institute for Health and Care Research.

Association between Ureaplasma colonization and bronchopulmonary dysplasia defined by different criteria in very low birth weight infants: A retrospective cohort study

OBJECTIVE

To study the association between Ureaplasma colonization and bronchopulmonary dysplasia (BPD) with different definitions in very low birth weight (VLBW) infants.

METHODS

A retrospective cohort study was performed with VLBW infants admitted from January 2019 to October 2021. Neonates with a positive respiratory tract Ureaplasma culture were included in the study group. Control group infants, matched for gestational age (±1 week), birth weight (±100 g), and birth year, had a negative respiratory tract Ureaplasma culture during the same period. The primary outcomes included the incidence and severity of BPD, defined by various criteria.

RESULTS

The study included 302 neonates (151 in the study group and 151 in the control group). After adjusting for confounders, Ureaplasma colonization was not associated with BPD as defined by the National Institutes of Health (NIH) in 2001 (adjusted odds ratio [aOR]: 0.820, 95% confidence interval [CI]: 0.362-1.860, p = .635). However, it was associated with BPD as defined by the NIH in 2018 (aOR: 2.490, 95% CI: 1.128-5.497, p = .024) and the Neonatal Research Network (NRN) in 2019 (aOR: 2.352, 95% CI: 1.077-5.134, p = .032). Additionally, VLBW infants with Ureaplasma colonization had a higher risk of moderate-severe BPD according to the NIH 2001 (aOR: 2.352, 95% CI: 1.077-5.134, p = .032), NIH 2018 (aOR: 6.339, 95% CI: 1.686-23.836, p = .006), and NRN 2019 definitions (aOR: 3.542, 95% CI: 1.267-9.904, p = .016).

CONCLUSIONS

Ureaplasma colonization is not associated with BPD by the NIH 2001 definition, but is associated with an increased incidence by the NIH 2018 or NRN 2019 definitions.

Epidemiological and Clinical Characteristics of Neonatal Ureaplasma urealyticum Infection

Purpose

To understand the epidemiology and clinical features of Ureaplasma urealyticum (UU) infection in hospitalized neonates due to vertical transmission from mother to child.

Methods

Respiratory secretions were collected from neonates hospitalized in the neonatology department of the Maternal and Child Health Hospital of Hubei Province from July 2020 to June 2022, and PCR was used to detect UU-DNA in respiratory secretions. The neonates were divided into UU-positive and UU-negative groups, the epidemiological and clinical characteristics of two groups, were statistically analyzed.

Results

A total of 7257 hospitalized neonates were included in this study, of whom 561 were UU positive and 6696 were UU negative, with a UU detection rate of 7.73%. The detection rate among female neonates was higher than male neonates, and the highest detection rate was found in the period from 1-7 days after birth; the detection rate was highest in spring and fall, and the lowest in winter, but the overall difference was not statistically significant (P>0.05). Compared with the UU-negative group, neonates in the UU-positive group were more likely to be preterm, have a lower birth weight, be delivered vaginally, and have maternal preterm rupture of membranes. In addition, neonates in the UU-positive group were more likely to be co-infected with pathogens and to have complications related to UU infections, which were all statistically significant (P<0.05).

Conclusion

Neonatal UU infections are detected more frequently in female infants, with the highest detection rate occurring in 1-7 days after birth, and the most prevalent periods for infection being spring and fall. Vaginal delivery and premature rupture of membranes may lead to an increased risk of vertical UU transmission from mother to child, and UU infection is strongly associated with preterm labor, low birth weight, pathogen co-infection, and related complications.

Clinical characteristics of preterm and term infants with Ureaplasma in gastric fluid

BACKGROUND

Ureaplasma spp. is an endemic microorganism that causes placental chorioamnionitis or preterm delivery in pregnant women, and the occurrence of bronchopulmonary dysplasia or intraventricular hemorrhaging in preterm infants after birth, although the pathogenicity of Ureaplasma remains controversial. The association between Ureaplasma exposure and the symptoms or outcomes of infected mothers or their infants born at term remains poorly understood. We investigated the clinical characteristics of preterm and term infants with or without Ureaplasma in their gastric fluid.

METHODS

Gastric fluid samples were collected from 47 newborns in the neonatal intensive-care unit immediately after birth and tested using multiplex polymerase chain reaction (PCR) assays targeting Ureaplasma spp., Ureaplasma parvum, and Ureaplasma urealyticum. The clinical findings and outcomes of the neonates and their mothers were retrospectively evaluated.

RESULTS

Ureaplasma spp. were detected in 9/47 samples (19%) by multiplex PCR assays. In all cases, the subspecies was U. parvum. The Ureaplasma-positive group had a significantly higher incidence of chorioamnionitis in utero than the Ureaplasma-negative group. Regarding preterm infants, the IgM levels in the Ureaplasma-positive group were significantly higher than in the Ureaplasma-negative group. In contrast, in term infants, the rates of a non-reassuring fetal status, a maternal fever, and maternal leukocyte counts and maternal C-reactive protein levels within five days before delivery in the Ureaplasma-positive group were significantly higher than those in the Ureaplasma-negative group. All three extremely-low-birth-weight infants with Ureaplasma developed bronchopulmonary dysplasia. The length of hospitalization in the Ureaplasma-positive group was almost same as that in the Ureaplasma-negative group for term infants.

CONCLUSION

Mothers or their fetuses with exposure to Ureaplasma expressed characteristic clinical features during pregnancy and after birth.

Clinical chorioamnionitis at term: definition, pathogenesis, microbiology, diagnosis, and treatment

Clinical chorioamnionitis, the most common infection-related diagnosis in labor and delivery units, is an antecedent of puerperal infection and neonatal sepsis. The condition is suspected when intrapartum fever is associated with two other maternal and fetal signs of local or systemic inflammation (eg, maternal tachycardia, uterine tenderness, maternal leukocytosis, malodorous vaginal discharge or amniotic fluid, and fetal tachycardia). Clinical chorioamnionitis is a syndrome caused by intraamniotic infection, sterile intraamniotic inflammation (inflammation without bacteria), or systemic maternal inflammation induced by epidural analgesia. In cases of uncertainty, a definitive diagnosis can be made by analyzing amniotic fluid with methods to detect bacteria (Gram stain, culture, or microbial nucleic acid) and inflammation (white blood cell count, glucose concentration, interleukin-6, interleukin-8, matrix metalloproteinase-8). The most common microorganisms are Ureaplasma species, and polymicrobial infections occur in 70% of cases. The fetal attack rate is low, and the rate of positive neonatal blood cultures ranges between 0.2% and 4%. Intrapartum antibiotic administration is the standard treatment to reduce neonatal sepsis. Treatment with ampicillin and gentamicin have been recommended by professional societies, although other antibiotic regimens, eg, cephalosporins, have been used. Given the importance of Ureaplasma species as a cause of intraamniotic infection, consideration needs to be given to the administration of antimicrobial agents effective against these microorganisms such as azithromycin or clarithromycin. We have used the combination of ceftriaxone, clarithromycin, and metronidazole, which has been shown to eradicate intraamniotic infection with microbiologic studies. Routine testing of neonates born to affected mothers for genital mycoplasmas could improve the detection of neonatal sepsis. Clinical chorioamnionitis is associated with decreased uterine activity, failure to progress in labor, and postpartum hemorrhage; however, clinical chorioamnionitis by itself is not an indication for cesarean delivery. Oxytocin is often administered for labor augmentation, and it is prudent to have uterotonic agents at hand to manage postpartum hemorrhage. Infants born to mothers with clinical chorioamnionitis near term are at risk for early-onset neonatal sepsis and for long-term disability such as cerebral palsy. A frontier is the noninvasive assessment of amniotic fluid to diagnose intraamniotic inflammation with a transcervical amniotic fluid collector and a rapid bedside test for IL-8 for patients with ruptured membranes. This approach promises to improve diagnostic accuracy and to provide a basis for antimicrobial administration.

Baseline azithromycin resistance in the gut microbiota of preterm born infants

BACKGROUND

Macrolides, including azithromycin, are increasingly used in preterm-born infants to treat Ureaplasma infections. The baseline carriage of macrolide resistance genes in the preterm stool microbiota is unknown.

OBJECTIVES

Identify carriage of azithromycin resistant bacteria and the incidence of macrolide resistant genes.

METHODS

Azithromycin resistant bacteria were isolated from serial stool samples obtained from preterm infants (≤32 weeks' gestation) by culturing aerobically/anaerobically, in the presence/absence of azithromycin. Using quantitative PCR, we targeted 6 common macrolide resistance genes (erm(A), erm(B), erm(C), erm(F), mef(A/E), msr(A)) in DNA extracted from selected bacteria resistant to azithromycin.

RESULTS

From 89 stool samples from 37 preterm-born infants, 93.3% showed bacterial growth in aerobic or anaerobic conditions. From the 280 azithromycin resistant isolates that were identified, Staphylococcus (75%) and Enterococcus (15%) species dominated. Macrolide resistance genes were identified in 91% of resistant isolates: commonest were erm(C) (46% of isolates) and msr(A) (40%). Multiple macrolide resistance genes were identified in 18% of isolates.

CONCLUSION

Macrolide resistance is common in the gut microbiota of preterm-born infants early in life, most likely acquired from exposure to the maternal microbiota. It will be important to assess modulation of macrolide resistance, if macrolide treatment becomes routine in the management of preterm infants.

IMPACT STATEMENT

Azithromycin resistance is present in the stool microbiota in the first month of life in preterm infants 91% of azithromycin resistant bacteria carried at least one of 6 common macrolide resistant genes Increasing use of macrolides in the preterm population makes this an important area of study.

Race and Ethnicity of Infants Enrolled in Neonatal Clinical Trials: A Systematic Review

Importance

Representativeness of populations within neonatal clinical trials is crucial to moving the field forward. Although racial and ethnic disparities in research inclusion are well documented in other fields, they are poorly described within neonatology.

Objective

To describe the race and ethnicity of infants included in a sample of recent US neonatal clinical trials and the variability in this reporting.

Evidence Review

A systematic search of US neonatal clinical trials entered into Cochrane CENTRAL 2017 to 2021 was conducted. Two individuals performed inclusion determination, data extraction, and quality assessment independently with discrepancies adjudicated by consensus.

Findings

Of 120 studies with 14 479 participants that met the inclusion criteria, 75 (62.5%) included any participant race or ethnicity data. In the studies that reported race and ethnicity, the median (IQR) percentage of participants of each background were 0% (0%-1%) Asian, 26% (9%-42%) Black, 3% (0%-12%) Hispanic, 0% (0%-0%) Indigenous (eg, Alaska Native, American Indian, and Native Hawaiian), 0% (0%-0%) multiple races, 57% (30%-68%) White, and 7% (1%-21%) other race or ethnicity. Asian, Black, Hispanic, and Indigenous participants were underrepresented, while White participants were overrepresented compared with a reference sample of the US clinical neonatal intensive care unit (NICU) population from the Vermont Oxford Network. Many participants were labeled as other race or ethnicity without adequate description. There was substantial variability in terms and methods of reporting race and ethnicity data. Geographic representation was heavily skewed toward the Northeast, with nearly one-quarter of states unrepresented.

Conclusions and Relevance

These findings suggest that neonatal research may perpetuate inequities by underrepresenting Asian, Black, Hispanic, and Indigenous neonates in clinical trials. Studies varied in documentation of race and ethnicity, and there was regional variation in the sites included. Based on these findings, funders and clinical trialists are advised to consider a 3-point targeted approach to address these issues: prioritize identifying ways to increase diversity in neonatal clinical trial participation, agree on a standardized method to report race and ethnicity among neonatal clinical trial participants, and prioritize the inclusion of participants from all regions of the US in neonatal clinical trials.

Pharmacotherapy of BPD: Current status & future perspectives

Bronchopulmonary dysplasia (BPD) is a disease exclusive to prematurity and has changed in its definition since Northway first described it in 1967. There have been countless clinical trials evaluating the efficacy of drugs in the treatment and prevention of BPD in human subjects, and an even larger number of animal studies. Despite these, only a handful of drugs are used at the bedside today, primarily due to the lack of consistent efficacy seen in clinical trials or due to reports of adverse effects. This review summarizes the list of the most commonly used drugs and emerging new therapies which target BPD and BPD-related pulmonary hypertension (BPD-PH), including those which have shown promise in human trials but are not yet used routinely.

Association of Ureaplasma infection pattern and azithromycin treatment effect with bronchopulmonary dysplasia in Ureaplasma positive infants: a cohort study

BACKGROUND

It is unclear whether Ureaplasma-associated pneumonia and azithromycin treatment affect the risk for bronchopulmonary dysplasia (BPD).

METHODS

A retrospective cohort study was performed in very low birth weight (VLBW) infants who tested positive for Ureaplasma within 72 h after birth in a tertiary unit. Chest X-ray (CXR) and laboratory test were performed before and after azithromycin treatment. Multivariate logistic regression analysis was used to identify the independent association between BPD and Ureaplasma-associated pneumonia, as well as BPD and effective azithromycin treatment.

RESULTS

A total of 118 infants were included in the current study, of whom 36 developed BPD (defined as supplemental oxygen needed at postmenstrual age 36 weeks or discharge). The rate of BPD was significantly higher in infants with Ureaplasma-associated pneumonia (44.6%) compared to infants with Ureaplasma colonization (17.7%, P = 0.002). After adjusting for confounders, an effective azithromycin treatment was significantly associated with reduced risk of BPD [odd ratio (OR) 0.011; 95% confidence interval (CI): 0.000-0.250), whereas Ureaplasma-associated pneumonia was not significantly associated with BPD (OR 1.835; 95% CI: 0.548-6.147).

CONCLUSION

Effective Azithromycin treatment in Ureaplasma positive VLBW infants was associated with a reduced risk of BPD.

Investigation of oral macrolide prescriptions in Japan using a retrospective claims database, 2013-2018

Macrolide usage in Japan exceeds that in Europe and the United States. Investigating the actual conditions in which macrolides are used is important for identifying further interventions for appropriate antimicrobial use; however, this situation has not been evaluated in Japan. Therefore, we aimed to clarify the number of macrolide prescriptions and their changes before and after implementation of the Antimicrobial Resistance (AMR) Action Plan. In addition, we also investigated the names of diseases for which macrolides have been prescribed and the number of days of prescription. A retrospective observational study was conducted using JMDC claims data from January 2013 to December 2018. The proportion of all oral antimicrobials and macrolides used during this period and the diseases for which macrolides were used in the 3 years before and after the AMR Action Plan were determined separately for acute (< 14 prescription days) and chronic (> 14 prescription days) diseases. The number of prescriptions for macrolides constituted approximately 30% of those for all oral antimicrobials; of these, clarithromycin accounted for approximately 60%. Most prescriptions for acute diseases were for common cold, whereas allergic and dermatological diseases were included among chronic diseases. The names of these illnesses did not change before and after the AMR Action Plan. Overall, these results indicate that appropriate macrolide use involves a review of their use for common cold along with appropriate evaluation of their long-term use for skin and allergic diseases. They also indicate the need for further fact-finding studies and ongoing AMR measures.

Predicting the likelihood of lower respiratory tract Ureaplasma infection in preterms

OBJECTIVE

To develop predictive models of Ureaplasma spp lower airway tract infection in preterm infants.

METHODS

A dataset was assembled from five cohorts of infants born <33 weeks gestational age (GA) enrolled over 17 years (1999-2016) with culture and/or PCR-confirmed tracheal aspirate Ureaplasma status in the first week of life (n=415). Seventeen demographic, obstetric and neonatal factors were analysed including admission white blood cell (WBC) counts. Best subset regression was used to develop three risk scores for lower airway Ureaplasma infection: (1) including admission laboratory values, (2) excluding admission laboratory values and (3) using only data known prenatally.

RESULTS

GA and rupture of membranes >72 hours were significant predictors in all 3 models. When all variables including admission laboratory values were included in the regression, WBC count was also predictive in the resulting model. When laboratory values were excluded, delivery route was found to be an additional predictive factor. The area under the curve for the receiver operating characteristic indicated high predictive ability of each model to identify infants with lower airway Ureaplasma infection (range 0.73-0.77).

CONCLUSION

We developed predictive models based on clinical and limited laboratory information available in the perinatal period that can distinguish between low risk (<10%) and high risk (>40%) of lower airway Ureaplasma infection. These may be useful in the design of phase III trials of therapeutic interventions to prevent Ureaplasma-mediated lung disease in preterm infants and in clinical management of at-risk 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.

The prevention and management strategies for neonatal chronic lung disease

INTRODUCTION

Survival from even very premature birth is improving, but long-term respiratory morbidity following neonatal chronic lung disease (bronchopulmonary dysplasia (BPD)) has not reduced. Affected infants may require supplementary oxygen at home, because they have more hospital admissions particularly due to viral infections and frequent, troublesome respiratory symptoms requiring treatment. Furthermore, adolescents and adults who had BPD have poorer lung function and exercise capacity.

AREAS COVERED

Antenatal and postnatal preventative strategies and management of infants with BPD. A literature review was undertaken using PubMed and Web of Science.

EXPERT OPINION

There are effective preventative strategies which include caffeine, postnatal corticosteroids, vitamin A, and volume guarantee ventilation. Side-effects, however, have appropriately caused clinicians to reduce use of systemically administered corticosteroids to infants only at risk of severe BPD. Promising preventative strategies which need further research are surfactant with budesonide, less invasive surfactant administration (LISA), neurally adjusted ventilatory assist (NAVA) and stem cells. The management of infants with established BPD is under-researched and should include identifying the optimum form of respiratory support on the neonatal unit and at home and which infants will most benefit in the long term from pulmonary vasodilators, diuretics, and bronchodilators.

Placing Ureaplasma within the Context of Bronchopulmonary Dysplasia Endotypes and Phenotypes

Different pathophysiological pathways (endotypes), leading to very preterm birth may result in distinct clinical phenotypes of bronchopulmonary dysplasia (BPD). Ureaplasma is a unique player in the pathogenesis of BPD. The interaction between factors inherent to Ureaplasma (virulence, bacterial load, duration of exposure), and to the host (immune response, infection clearance, degree of prematurity, respiratory support, concomitant infections) may contribute to BPD development in a variable manner. The data reviewed herein support the hypothesis that Ureaplasma, as a representative of the infectious/inflammatory endotype, may produce pulmonary damage predominantly in parenchyma, interstitium, and small airways. In contrast, Ureaplasma may have a very limited role in the pathogenesis of the vascular phenotype of BPD. In addition, if Ureaplasma is a key factor in BPD pathogenesis, its eradication by macrolides should prevent BPD. However, various meta-analyses do not show consistent evidence that this is the case. The limitations of current definitions and classifications of BPD, based on respiratory support needs instead of pathophysiology and phenotypes, may explain this and other failures in strategies aimed to prevent BPD. The precise mechanisms through which Ureaplasma infection leads to altered lung development and how these pathways can result in different BPD phenotypes warrant further investigation.

Detection of pathogens associated with early-onset neonatal sepsis in cord blood at birth using quantitative PCR

Background: Early onset neonatal sepsis (EONS) typically begins prior to, during or soon after birth and may be rapidly fatal. There is paucity of data on the aetiology of EONS in sub-Saharan Africa due to limited diagnostic capacity in this region, despite the associated significant mortality and long-term neurological impairment. Methods: We compared pathogens detected in cord blood samples between neonates admitted to hospital with possible serious bacterial infection (pSBI) in the first 48 hours of life (cases) and neonates remaining well (controls). Cord blood was systematically collected at Kilifi County Hospital (KCH) from 2011-2016, and later tested for 21 bacterial, viral and protozoal targets using multiplex PCR via TaqMan Array Cards (TAC). Results: Among 603 cases (101 [17%] of whom died), 179 (30%) tested positive for ≥1 target and 37 (6.1%) tested positive for multiple targets. Klebsiella oxytoca, Escherichia coli/Shigella spp., Pseudomonas aeruginosa, and Streptococcus pyogenes were commonest. Among 300 controls, 79 (26%) tested positive for ≥1 target, 11 (3.7%) were positive for multiple targets, and K. oxytoca and P. aeruginosa were most common. Cumulative odds ratios across controls: cases (survived): cases (died) were E. coli/Shigella spp. 2.6 (95%CI 1.6-4.4); E. faecalis 4.0 (95%CI 1.1-15); S. agalactiae 4.5 (95%CI 1.6-13); Ureaplasma spp. 2.9 (95%CI 1.3-6.4); Enterovirus 9.1 (95%CI 2.3-37); and Plasmodium spp. 2.9 (95%CI 1.4-6.2). Excluding K. oxytoca and P. aeruginosa as likely contaminants, aetiology was attributed in 9.4% (95%CI 5.1-13) cases using TAC. Leading pathogen attributions by TAC were E. coli/Shigella spp. (3.5% (95%CI 1.7-5.3)) and Ureaplasma spp. (1.7% (95%CI 0.5-3.0)). Conclusions: Cord blood sample may be useful in describing EONS pathogens at birth, but more specific tests are needed for individual diagnosis. Careful sampling of cord blood using aseptic techniques is crucial to minimize contamination. In addition to culturable bacteria, Ureaplasma and Enterovirus were causes of EONS.

Intrauterine Ureaplasma is associated with small airway obstruction in extremely preterm infants

BACKGROUND

The long-term follow-up of lung function (LF) in extremely preterm (EP) infants with bronchopulmonary dysplasia (BPD) has shown a worldwide increase in small airway obstructions (SAO).

OBJECTIVES

We investigated the relationships between intrauterine Ureplasma infection in EP infants and bubbly/cystic lung, BPD, and SAO at school age.

METHODS

Placental pathology, placental Ureaplasma DNA (pU-DNA), and cord blood immunoglobulin M (IgM) (C-IgM) were investigated in 360 EP infants born from 1981 to 2004. Maternal amniotic inflammatory response (M-AIR) scores and hemosiderin deposition (HD) were estimated in the chorioamnion. The study subjects were divided into groups based on their M-AIR scores. Their LF at school age was compared with those of 33 healthy siblings.

FINDINGS

pU-DNA and C-IgM were significantly related to SAO at school age (p < 0.012). M-AIR score 3 and pU-DNA >1000 units had an odds ratio (OR) of 35 (95% confidence interval: 10-172) and 18 (5.6-67) for bubbly/cystic lung, and 11 (3.1 - 43) and 31 (4.5-349) for severe BPD, and 5.3 (2.1-11) and 12 (2.4-74) for SAO, respectively. The ORs of surfactant treatment, BPD grade III, O₂ at 40 weeks, HD, and C-IgM >30 mg/dl for SAO were 0.21 (0.075-0.58), 5.3 (2.1-15), 2.5 (1.4-4.6), 3.6 (1.5-9.1) and 2.5 (1.0-5.2). 84% (90/107) SAO infants showed no or mild BPD in infancy, and 61% of infants had no severe CAM.

CONCLUSION

Our long-term cohort study of LF in EP infants revealed that intrauterine Ureaplasma was associated with bubbly/cystic lung, severe BPD, and SAO at school age.

Follow-up study of infants recruited to the randomised, placebo-controlled trial of azithromycin for the prevention of chronic lung disease of prematurity in preterm infants-study protocol for the AZTEC-FU study

Background

Preterm birth, especially at less than 30 weeks’ gestation, is significantly associated with respiratory, neurodevelopmental and growth abnormalities. The AZTEC study has recruited 799 infants born at < 30 weeks’ gestation to determine if a ten-day intravenous treatment with azithromycin improves survival without development of chronic lung disease of prematurity (CLD) at 36 weeks’ post menstrual age (PMA) when compared to placebo. The follow-up studies will compare respiratory, neurodevelopmental and growth outcomes up to 2 years of corrected age between infants who received azithromycin and those who received placebo in the early neonatal period.

Methods

Survivors at 36 weeks’ PMA from the main Azithromycin Therapy for Chronic Lung Disease of Prematurity (AZTEC) study with parental consent will continue to be followed up to discharge from the neonatal unit and to 2 years of corrected age. Length of stay, rates of home oxygen, length of supplemental oxygen requirement, hospital admissions, drug usage, respiratory illness, neurodevelopmental disability and death rates will be reported. Data is being collected via parentally completed respiratory and neurodevelopmental questionnaires at 1 and 2 years of corrected age respectively. Additional information is being obtained from various sources including hospital discharge and clinical letters from general practitioners and hospitals as well as from national databases including the National Neonatal Research Database and NHS Digital.

Discussion

The AZTEC-FU study will assess mortality and important neonatal morbidities including respiratory, neurodevelopmental and growth outcomes. Important safety data will also be collected, including the incidence of potential consequences of early macrolide use, primarily pyloric stenosis. This study may have implications on future neonatal care.

Trial registration

The study was retrospectively registered on ISRCTN (ISRCTN47442783).

AZTEC-azithromycin therapy for prevention of chronic lung disease of prematurity: a statistical analysis plan for clinical outcomes

BACKGROUND

The AZTEC trial is a multi-centre, randomised, placebo-controlled trial of azithromycin to improve survival without development of chronic lung disease of prematurity (CLD) in preterm infants. The statistical analysis plan for the clinical outcomes of the AZTEC trial is described.

METHODS AND DESIGN

A double-blind, randomised, placebo-controlled trial of a 10-day course of intravenous azithromycin (20 mg/kg for 3 days; 10 mg/kg for 7 days) administered to preterm infants born at < 30 weeks' gestational age across UK tertiary neonatal units. Following parental consent, infants are randomly allocated to azithromycin or placebo, with allocated treatment starting within 72 h of birth. The primary outcome is survival without moderate/severe CLD at 36 weeks' postmenstrual age (PMA). Serial respiratory fluid and stool samples are being collected up to 21 days of life. The target sample size is 796 infants, which is based on detecting a 12% absolute difference in survival without moderate/severe CLD at 36 weeks' PMA (90% power, two-sided alpha of 0.05) and includes 10% loss to follow-up.

RESULTS

Baseline demographic and clinical characteristics will be summarised by treatment arm and in total. Categorical data will be summarised by numbers and percentages. Continuous data will be summarised by mean, standard deviation, if data are normal, or median, interquartile range, if data are skewed. Tests of statistical significance will not be undertaken for baseline characteristics. The primary analysis, on the intention to treat (ITT) population, will be analysed using multilevel logistic regression, within a multiple imputation framework. Adjusted odds ratios, 95% confidence intervals, and p-values will be presented. For all other analyses, the analysis population will be based on the complete case population, which is a modified ITT population. All analyses will be adjusted for gestational age and treatment arm and account for any clustering by centre and/or multiple births as a random effect.

CONCLUSION

We describe the statistical analysis plan for the AZTEC trial, including the analysis principles, definitions of the key clinical outcomes, methods for primary analysis, pre-specified subgroup analysis, sensitivity analysis, and secondary analysis. The plan has been finalised prior to the completion of recruitment.

TRIAL REGISTRATION

ISRCTN registry ISRCTN11650227. Registered on 31 July 2018.

Azithromycin reduces inflammation-amplified hypoxic-ischemic brain injury in neonatal rats

BACKGROUND

Systemic inflammation amplifies neonatal hypoxic-ischemic (HI) brain injury. Azithromycin (AZ), an antibiotic with anti-inflammatory properties, improves sensorimotor function and reduces tissue damage after neonatal rat HI brain injury. The objective of this study was to determine if AZ is neuroprotective in two neonatal rat models of inflammation-amplified HI brain injury.

DESIGN/METHODS

Seven-day-old (P7) rats received injections of toll-like receptor agonists lipopolysaccharide (LPS) or Pam₃Cys-Ser-(Lys)₄ (PAM) prior to right carotid ligation followed by 50 min (LPS + HI) or 60 min (PAM + HI) in 8% oxygen. Outcomes included contralateral forelimb function (forepaw placing; grip strength), survival, %Intact right hemisphere (brain damage), and a composite score incorporating these measures. We compared postnatal day 35 outcomes in controls and groups treated with three or five AZ doses. Then, we compared P21 outcomes when the first (of five) AZ doses were administered 1, 2, or 4 h after HI.

RESULTS

In both LPS + HI and PAM + HI models, AZ improved sensorimotor function, survival, brain tissue preservation, and composite scores. Benefits increased with five- vs. three-dose AZ and declined with longer initiation delay.

CONCLUSIONS

Perinatal systemic infection is a common comorbidity of neonatal asphyxia brain injury and contributes to adverse outcomes. These data support further evaluation of AZ as a candidate treatment for neonatal neuroprotection.

IMPACT

AZ treatment decreases sensorimotor impairment and severity of brain injury, and improves survival, after inflammation-amplified HI brain injury, and this can be achieved even with a 2 h delay in initiation. This neuroprotective benefit is seen in models of inflammation priming by both Gram-negative and Gram-positive infections. This extends our previous findings that AZ treatment is neuroprotective after HI brain injury in neonatal rats.

Detection of pathogens associated with early-onset neonatal sepsis in cord blood at birth using quantitative PCR

Background: Early onset neonatal sepsis (EONS) typically begins prior to, during or soon after birth and may be rapidly fatal. There is paucity of data on the aetiology of EONS in sub-Saharan Africa due to limited diagnostic capacity in this region, despite the associated significant mortality and long-term neurological impairment. Methods: We compared pathogens detected in cord blood samples between neonates admitted to hospital with possible serious bacterial infection (pSBI) in the first 48 hours of life (cases) and neonates remaining well (controls). Cord blood was systematically collected at Kilifi County Hospital (KCH) from 2011-2016, and later tested for 21 bacterial, viral and protozoal targets using multiplex PCR via TaqMan Array Cards (TAC). Results: Among 603 cases (101 [17%] of whom died), 179 (30%) tested positive for ≥1 target and 37 (6.1%) tested positive for multiple targets. Klebsiella oxytoca, Escherichia coli/Shigella spp., Pseudomonas aeruginosa, and Streptococcus pyogenes were commonest. Among 300 controls, 79 (26%) tested positive for ≥1 target, 11 (3.7%) were positive for multiple targets, and K. oxytoca and P. aeruginosa were most common. Cumulative odds ratios across controls: cases (survived): cases (died) were E. coli/Shigella spp. 2.6 (95%CI 1.6-4.4); E. faecalis 4.0 (95%CI 1.1-15); S. agalactiae 4.5 (95%CI 1.6-13); Ureaplasma spp. 2.9 (95%CI 1.3-6.4); Enterovirus 9.1 (95%CI 2.3-37); and Plasmodium spp. 2.9 (95%CI 1.4-6.2). Excluding K. oxytoca and P. aeruginosa as likely contaminants, aetiology was attributed in 9.4% (95%CI 5.1-13) cases using TAC. Leading pathogen attributions by TAC were E. coli/Shigella spp. (3.5% (95%CI 1.7-5.3)) and Ureaplasma spp. (1.7% (95%CI 0.5-3.0)). Conclusions: Cord blood sample may be useful in describing EONS pathogens at birth, but more specific tests are needed for individual diagnosis. Careful sampling of cord blood using aseptic techniques is crucial to minimize contamination. In addition to culturable bacteria, Ureaplasma and Enterovirus were causes of EONS.

Moving Bronchopulmonary Dysplasia Research from the Bedside to the Bench

Although advances in the respiratory management of extremely preterm infants have led to improvements in survival, this progress has not yet extended to a reduction in the incidence of bronchopulmonary dysplasia (BPD). BPD is a complex multifactorial condition that primarily occurs due to disturbances in the regulation of normal pulmonary airspace and vascular development. Preterm birth and exposure to invasive mechanical ventilation also compromises large airway development, leading to significant morbidity and mortality. Although both predisposing and protective genetic and environmental factors have been frequently described in the clinical literature, these findings have had limited impact on the development of effective therapeutic strategies. This gap is likely because the molecular pathways that underlie these observations are yet not fully understood, limiting the ability of researchers to identify novel treatments that can preserve normal lung development and/or enhance cellular repair mechanisms. In this review article, we will outline various well-established clinical observations whilst identifying key knowledge gaps that need to be filled with carefully designed pre-clinical experiments. We will address these issues by discussing controversial topics in the pathophysiology, the pathology and the treatment of BPD, including an evaluation of existing animal models that have been used to answer important questions.

Pharmacotherapy in Bronchopulmonary Dysplasia: What Is the Evidence?

Bronchopulmonary Dysplasia (BPD) is a multifactorial disease affecting over 35% of extremely preterm infants born each year. Despite the advances made in understanding the pathogenesis of this disease over the last five decades, BPD remains one of the major causes of morbidity and mortality in this population, and the incidence of the disease increases with decreasing gestational age. As inflammation is one of the key drivers in the pathogenesis, it has been targeted by majority of pharmacological and non-pharmacological methods to prevent BPD. Most extremely premature infants receive a myriad of medications during their stay in the neonatal intensive care unit in an effort to prevent or manage BPD, with corticosteroids, caffeine, and diuretics being the most commonly used medications. However, there is no consensus regarding their use and benefits in this population. This review summarizes the available literature regarding these medications and aims to provide neonatologists and neonatal providers with evidence-based recommendations.

Detection of pathogens associated with early-onset neonatal sepsis in cord blood at birth using quantitative PCR

Background: Early onset neonatal sepsis (EONS) typically begins prior to, during or soon after birth and may be rapidly fatal. There is paucity of data on the aetiology of EONS in sub-Saharan Africa due to limited diagnostic capacity in this region, despite the associated significant mortality and long-term neurological impairment. Methods: We compared pathogens detected in cord blood samples between neonates admitted to hospital with possible serious bacterial infection (pSBI) in the first 48 hours of life (cases) and neonates remaining well (controls). Cord blood was systematically collected at Kilifi County Hospital (KCH) from 2011-2016, and later tested for 21 bacterial, viral and protozoal targets using multiplex PCR via TaqMan Array Cards (TAC). Results: Among 603 cases (101 [17%] of whom died), 179 (30%) tested positive for ≥1 target and 37 (6.1%) tested positive for multiple targets. Klebsiella oxytoca, Escherichia coli/Shigella spp., Pseudomonas aeruginosa, and Streptococcus pyogenes were commonest. Among 300 controls, 79 (26%) tested positive for ≥1 target, 11 (3.7%) were positive for multiple targets, and K. oxytoca and P. aeruginosa were most common. Cumulative odds ratios across controls: cases (survived): cases (died) were E. coli/Shigella spp. 2.6 (95%CI 1.6-4.4); E. faecalis 4.0 (95%CI 1.1-15); S. agalactiae 4.5 (95%CI 1.6-13); Ureaplasma spp. 2.9 (95%CI 1.3-6.4); Enterovirus 9.1 (95%CI 2.3-37); and Plasmodium spp. 2.9 (95%CI 1.4-6.2). Excluding K. oxytoca and P. aeruginosa as likely contaminants, aetiology was attributed in 9.4% (95%CI 5.1-13) cases using TAC. Leading pathogen attributions by TAC were E. coli/Shigella spp. (3.5% (95%CI 1.7-5.3)) and Ureaplasma spp. (1.7% (95%CI 0.5-3.0)). Conclusions: Cord blood sample may be useful in describing EONS pathogens at birth, but more specific tests are needed for individual diagnosis. Careful sampling of cord blood using aseptic techniques is crucial to minimize contamination. In addition to culturable bacteria, Ureaplasma and Enterovirus were causes of EONS.

The Airway Microbiome and Metabolome in Preterm Infants: Potential Biomarkers of Bronchopulmonary Dysplasia

OBJECTIVES

We investigated the genomic and metabolic characteristics of the airway microbiome in mild, moderate, severe, and non-bronchopulmonary dysplasia (BPD) preterm infants and explored possible mechanisms underlying BPD.

METHODS

Twenty-eight preterm infants with gestational age ≤34 weeks and intubated within 24 h after birth were enrolled. According to the severity of BPD, the patients were divided into mild, moderate and severe BPD groups, and the non-BPD group was the control group. Tracheal aspirates (TA) were obtained at intubation and on day 7 after birth. The bacterium in the aspirates were sequenced by 16S rRNA, and the metabolomics of the aspirates were identified by high performance liquid chromatography-quadrupole time of flight mass spectrometry (UHPLC-Q-TOF/MS). The correlation between the differential metabolite and differential bacteria was investigated using Pearson's correlation coefficient corrected for gestational age and birth weight and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases.

RESULTS

There were significant differences in the diversity and composition of airway microbiome and metabolome between severe, moderate and mild BPD and non-BPD premature infants. At birth (day 1), the difference was more pronounced than at day 7. The diversity of airway microbial community decreased, the abundance of Stenotrophomonas increased, and the increased level of sn-glycerol 3-phosphoethanolamine was positively correlated with the severity of BPD. There was a significant positive correlation between the abundance of Stenotrophomonas and the level of sn-glycerol 3-phosphoethanolamine.

CONCLUSION

Decreased diversity of the airway microbiome, increased abundance of Stenotrophomonas, and increased level of sn-glycerol 3-phosphoethanolamine may have potential as biomarkers for BPD. The occurrence and severity of BPD are closely related to Stenotrophomonas, which may influence the composition of the lower airway microbiome through its metabolite sn-glycerol 3-phosphoethanolamine, and may be the triggering factor of the disease. The causal relationship needs further study.

Randomized trial of azithromycin to eradicate Ureaplasma respiratory colonization in preterm infants: 2-year outcomes

BACKGROUND

To assess the potential impact of azithromycin treatment in the first week following birth on 2-year outcomes in preterm infants with and without Ureaplasma respiratory colonization who participated in a double-blind, placebo-controlled randomized controlled trial.

METHODS

Respiratory morbidity was assessed at NICU discharge and at 6, 12, and 22-26 months corrected age using pulmonary questionnaires. Comprehensive neurodevelopmental assessments were completed between 22 and 26 months corrected age. The primary and secondary composite outcomes were death or severe respiratory morbidity and death or moderate-severe neurodevelopmental impairment, respectively, at 22-26 months corrected age.

RESULTS

One hundred and twenty-one randomized participants (azithromycin, N = 60; placebo, N = 61) were included in the intent-to-treat analysis. There were no significant differences in death or serious respiratory morbidity (34.8 vs 30.4%, p = 0.67) or death or moderate-severe neurodevelopmental impairment (47 vs 33%, p = 0.11) between the azithromycin and placebo groups. Among all trial participants, tracheal aspirate Ureaplasma-positive infants experienced a higher frequency of death or serious respiratory morbidity at 22-26 months corrected age (58%) than tracheal aspirate Ureaplasma-negative infants (34%) or non-intubated infants (21%) (p = 0.028).

CONCLUSIONS

We did not observe strong evidence of a difference in long-term pulmonary and neurodevelopment outcomes in preterm infants treated with azithromycin in the first week of life compared to placebo.

IMPACT

No strong evidence of a difference in long-term pulmonary and neurodevelopment outcomes was identified at 22-26 months corrected age in infants treated with azithromycin in the first week of life compared to placebo. The RCT is the first study of 2-year pulmonary and neurodevelopmental outcomes of azithromycin treatment in ELGANs. Provides evidence that ELGANs with lower respiratory tract Ureaplasma have the most frequent serious respiratory morbidity in the first 2 years of life, suggesting that a Phase III trial of azithromycin to prevent BPD targeting this population is warranted.

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.

Torsade de pointe due to QT prolongation following erythromycin administration in a preterm infant

BACKGROUND

Neonatal sepsis is a major cause of morbidity and mortality in preterm infants. Chorioamnionitis is an important risk factor for the development of sepsis, therefore neonates born to mothers developing signs of amnionitis need to be treated with antibiotics immediately after birth. Ureaplasma spp can be a causative agent of vaginal or intra amniotic infection needing antibiotic treatment. Macrolides are frequently used to treat maternal intrauterine infection, but antibiotic treatment of the neonate should be consciously chosen with consideration of potential side effects. Indeed, macrolides are great purveyors of heart rhythm disorders.

CASE PRESENTATION

We describe the case of a 29 weeks preterm infant born to a mother with Ureaplasma spp infection. The baby was treated with erythromycin immediately after birth. During the second day of life, the baby presented some episodes of tachyarrhythmia with premature ventricular beats (PVBs) that were followed by a non-sustained ventricular tachycardia as high as 270 bpm leading to a cardiac arrest. After resuscitation, tachycardia resolved but the rhythm was characterised by numerous PVBs and an electrocardiogram (ECG) diagnosed a Long QT Syndrome (LQTS). Erythromycin was discontinued, and the rhythm normalised a few days after withdrawal.

CONCLUSIONS

Erythromycin should be administered in neonates only if no other choice is available, as although generally well tolerated, its administration can be associated with QTc interval prolongation. When no other option is available, paediatricians should be aware to perform cardiac monitoring or at least serial ECGs before and during erythromycin administration.

An Update on the Prevention and Management of Bronchopulmonary Dysplasia

Bronchopulmonary dysplasia (BPD) is a common morbidity affecting preterm infants and is associated with substantial long-term disabilities. There has been no change in the incidence of BPD over the past 20 years, despite improvements in survival and other outcomes. The preterm lung is vulnerable to injuries occurring as a result of invasive ventilation, hyperoxia, and infections that contribute to the development of BPD. Clinicians caring for infants in the neonatal intensive care unit use multiple therapies for the prevention and management of BPD. Non-invasive ventilation strategies and surfactant administration via thin catheters are treatment approaches that aim to avoid volutrauma and barotrauma to the preterm developing lung. Identifying high-risk infants to receive postnatal corticosteroids and undergo patent ductus arteriosus closure may help to individualize care and promote improved lung outcomes. In infants with established BPD, outpatient management is complex and requires coordination from several specialists and therapists. However, most current therapies used to prevent and manage BPD lack solid evidence to support their effectiveness. Further research is needed with appropriately defined outcomes to develop effective therapies and impact the incidence of BPD.

Status of inhalable antimicrobial agents for lung infection: progress and prospects

Introduction: Available parenteral and oral administration of antimicrobial agents (AMAs) in respiratory infections often show less penetration into the lung parenchyma. Due to inappropriate dose availability, the rate of antibiotic resistance is increasing gradually. Inhaled antibiotics intensely improve the availability of drugs at the site of respiratory infections. This targeted delivery minimizes systemic exposure and associated toxicity.Area covers: This review was performed by searching in the scientific database like PubMed and several trusted government sites like fda.gov, cdc.gov, ClinicalTrials.gov, etc. For better understanding, AMAs are classified in different stages of approval. Mechanism and characterization of pulmonary drug deposition section helps to understand the effective delivery of AMAs to the respiratory tract. There is a need for proper adoption of delivery devices for inhalable AMAs. Thus, delivery devices are extensively explained. Inspiratory flow has a remarkable impact on the delivery device that has been explained in detail.Expert opinion: Pulmonary delivery restricts the bulk administration of drugs in comparison with other routes. Therefore, novel AMAs with higher bactericidal activity at lower concentrations need to be synthesized. Extensive research is indeed in developing innovative delivery devices that would able to deliver higher doses of AMAs through the pulmonary route.

Azithromycin for preventing bronchopulmonary dysplasia in preterm infants: A systematic review and meta-analysis

CONTEXT

Azithromycin has anti-Ureaplasma and anti-inflammatory properties that might help reduce lung injury in preterm infants.

OBJECTIVE

To test the efficacy and safety of prophylactic or therapeutic azithromycin in preventing bronchopulmonary dysplasia (BPD) in preterm infants with unknown or proven Ureaplasma status.

METHODS

We searched PubMed, Web of Science, and Cochrane Library until 13 September 2020. Two authors independently assessed the eligibility, risk of bias, and extracted the data. We performed a random-effects model meta-analysis to yield pooled relative risk (RR) or mean difference (MD) with 95% confidence interval (CI). We used the Cochrane GRADE methodology for summarizing the results.

RESULTS

We included five randomized clinical trials. The meta-analysis revealed no significant differences in BPD (RR, 0.92; 95% CI, 0.71, 1.19; low-quality evidence), death (RR, 0.75; 95% CI, 0.52, 1.10; low-quality evidence), and BPD or death (RR, 0.90; 95% CI, 0.74, 1.10; low-quality evidence). However, a significantly lower BPD or death (RR, 0.83; 95% CI, 0.70, 0.99) and a trend toward lower BPD (RR, 0.83; 95% CI, 0.66, 1.03) with azithromycin therapy was noted in Ureoplasma positive neonates. No differences in secondary outcomes were noted, except for significantly lower supplemental oxygen days with azithromycin (MD, -6.06; 95% CI, -7.40, -4.72; moderate-quality evidence). The test for subgroup differences between short (<7 days) and long (>7 days) course of azithromycin were nonsignificant for all the outcomes.

CONCLUSION

Low-quality evidence suggests azithromycin therapy reduces BPD or death in preterm infants with positive Ureoplasma, but not in all preterm infants.

New Pharmacologic Approaches to Bronchopulmonary Dysplasia

Bronchopulmonary Dysplasia is the most common long-term respiratory morbidity of preterm infants, with the risk of development proportional to the degree of prematurity. While its pathophysiologic and histologic features have changed over time as neonatal demographics and respiratory therapies have evolved, it is now thought to be characterized by impaired distal lung growth and abnormal pulmonary microvascular development. Though the exact sequence of events leading to the development of BPD has not been fully elucidated and likely varies among patients, it is thought to result from inflammatory and mechanical/oxidative injury from chronic ventilatory support in fragile, premature lungs susceptible to injury from surfactant deficiency, structural abnormalities, inadequate antioxidant defenses, and a chest wall that is more compliant than the lung. In addition, non-pulmonary issues may adversely affect lung development, including systemic infections and insufficient nutrition. Once BPD has developed, its management focuses on providing adequate gas exchange while promoting optimal lung growth. Pharmacologic strategies to ameliorate or prevent BPD continue to be investigated. A variety of agents, to be reviewed henceforth, have been developed or re-purposed to target different points in the pathways that lead to BPD, including anti-inflammatories, diuretics, steroids, pulmonary vasodilators, antioxidants, and a number of molecules involved in the cell signaling cascade thought to be involved in the pathogenesis of BPD.

T Lymphocytes, Multi-Omic Interactions and Bronchopulmonary Dysplasia

Bronchopulmonary dysplasia (BPD) remains a significant clinical challenge in neonatal medicine. BPD is clearly a multifactorial disease with numerous antenatal and postnatal components influencing lung development. Extremely immature infants are born in the late canalicular or early saccular stage and usually receive intensive care until the early alveolar stage of lung development, resulting in varying magnitudes of impairment of alveolar septation, lung fibrosis, and abnormal vascular development. The interactions between T lymphocytes, the genome and the epigenome, the microbiome and the metabolome, as well as nutrition and therapeutic interventions such as the exposure to oxygen, volutrauma, antibiotics, corticosteroids, caffeine and omeprazole, play an important role in pathogenesis and disease progression. While our general understanding of these interactions thanks to basic research is improving, this knowledge is yet to be translated into comprehensive prevention and clinical management strategies for the benefit of preterm infants developing BPD and later during infancy and childhood suffering from the disease itself and its sequelae. In this review, we summarise existing evidence on the interplay between T lymphocytes, lung multi-omics and currently used therapeutic interventions in BPD, and highlight avenues for potential future immunology related research in the field.

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.

Study protocol: azithromycin therapy for chronic lung disease of prematurity (AZTEC) - a randomised, placebo-controlled trial of azithromycin for the prevention of chronic lung disease of prematurity in preterm infants

INTRODUCTION

Chronic lung disease of prematurity (CLD), also known as bronchopulmonary dysplasia (BPD), is a cause of significant respiratory morbidity in childhood and beyond. Coupled with lung immaturity, infections (especially by Ureaplasma spp) are implicated in the pathogenesis of CLD through promotion of pulmonary inflammation. Azithromycin, which is a highly effective against Ureaplasma spp also has potent anti-inflammatory properties. Thus, azithromycin therapy may improve respiratory outcomes by targeting infective and inflammatory pathways. Previous trials using macrolides have not been sufficiently powered to definitively assess CLD rates. To address this, the azithromycin therapy for chronic lung disease of prematurity (AZTEC) trial aims to determine if a 10-day early course of intravenous azithromycin improves rates of survival without CLD when compared with placebo with an appropriately powered study.

METHODS AND ANALYSIS

796 infants born at less than 30 weeks' gestational age who require at least 2 hours of continuous respiratory support within the first 72 hours following birth are being enrolled by neonatal units in the UK. They are being randomised to receive a double-blind, once daily dose of intravenous azithromycin (20 mg/kg for 3 days, followed by 10 mg/kg for a further 7 days), or placebo. CLD is being assessed at 36 weeks' PMA. Whether colonisation with Ureaplasma spp prior to randomisation modifies the treatment effect of azithromycin compared with placebo will also be investigated. Secondary outcomes include necrotising enterocolitis, intraventricular/cerebral haemorrhage, retinopathy of prematurity and nosocomial infections, development of antibiotic resistance and adverse reactions will be monitored.

ETHICS AND DISSEMINATION

Ethics permission has been granted by Wales Research Ethics Committee 2 (Ref 18/WA/0199), and regulatory permission by the Medicines and Healthcare Products Regulatory Agency (Clinical Trials Authorisation reference 21323/0050/001-0001). The study is registered on ISRCTN (ISRCTN11650227). The study is overseen by an independent Data Monitoring Committee and an independent Trial Steering Committee. We shall disseminate our findings via national and international peer-reviewed journals, and conferences. A summary of the findings will also be posted on the trial website.

Neonatal Mycoplasma and Ureaplasma Infections

Mycoplasma species (spp.) can be commensals or opportunistic pathogens of the urogenital tract, and they can be commonly isolated from amniotic fluid, placenta, and fetal/neonatal tissue or blood in mothers delivering prematurely or their preterm infants. Although the presence of Mycoplasma spp. has been associated with adverse maternal-fetal outcomes such as preterm birth and maternal chorioamnionitis, it is less clear whether vertical transmission to the neonate results in colonization or active infection/inflammation. Moreover, the presence of Mycoplasma spp. in neonatal blood, cerebrospinal fluid, or tissue has been variably associated with increased risk of neonatal comorbidities, especially bronchopulmonary dysplasia (BPD). Although the treatment of the mother or neonate with antibiotics is effective in eradicating ureaplasma, it is not clear that the treatment is effective in reducing the incidence of major morbidities of the preterm neonate (eg, BPD). In this article, we review the animal and clinical data for ureaplasma-related complications and treatment strategies. [Pediatr Ann. 2020;49(7):e305-e312.].

Perspectives on Probiotics and Bronchopulmonary Dysplasia

Bronchopulmonary dysplasia (BPD) is a chronic respiratory disease of preterm infants, associated with high morbidity and hospitalization expenses. With the revolutionary advances in microbiological analysis technology, increasing evidence indicates that children with BPD are affected by lung microbiota dysbiosis, which may be related to the illness occurrence and progression. However, dysbiosis treatment in BPD patients has not been fully investigated. Probiotics are living microorganisms known to improve human health for their anti-inflammatory and anti-tumor effects, and particularly by balancing gut microbiota composition, which promotes gut-lung axis recovery. The aim of the present review is to examine current evidence of lung microbiota dysbiosis and explore potential applications of probiotics in BPD, which may provide new insights into treatment strategies of this disease.