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Sakaria RP, Dhanireddy R. Pharmacotherapy in Bronchopulmonary Dysplasia: What Is the Evidence? Front Pediatr 2022; 10:820259. [PMID: 35356441 PMCID: PMC8959440 DOI: 10.3389/fped.2022.820259] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/22/2021] [Accepted: 01/26/2022] [Indexed: 11/13/2022] Open
Abstract
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.
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Affiliation(s)
- Rishika P. Sakaria
- Department of Pediatrics, University of Tennessee Health Science Center, Memphis, TN, United States
| | - Ramasubbareddy Dhanireddy
- Department of Pediatrics, University of Tennessee Health Science Center, Memphis, TN, United States
- Department of Obstetrics and Gynecology, University of Tennessee Health Science Center, Memphis, TN, United States
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Viscardi RM, Terrin ML, Magder LS, Davis NL, Dulkerian SJ, Waites KB, Ambalavanan N, Kaufman DA, Donohue P, Tuttle DJ, Weitkamp JH, Hassan HE, Eddington ND. Randomised trial of azithromycin to eradicate Ureaplasma in preterm infants. Arch Dis Child Fetal Neonatal Ed 2020; 105:615-622. [PMID: 32170033 PMCID: PMC7592356 DOI: 10.1136/archdischild-2019-318122] [Citation(s) in RCA: 34] [Impact Index Per Article: 8.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/20/2019] [Revised: 01/26/2020] [Accepted: 02/25/2020] [Indexed: 12/22/2022]
Abstract
OBJECTIVE To test whether azithromycin eradicates Ureaplasma from the respiratory tract in preterm infants. DESIGN Prospective, phase IIb randomised, double-blind, placebo-controlled trial. SETTING Seven level III-IV US, academic, neonatal intensive care units (NICUs). PATIENTS Infants 240-286 weeks' gestation (stratified 240-266; 270-286 weeks) randomly assigned within 4 days following birth from July 2013 to August 2016. INTERVENTIONS Intravenous azithromycin 20 mg/kg or an equal volume of D5W (placebo) every 24 hours for 3 days. MAIN OUTCOME MEASURES The primary efficacy outcome was Ureaplasma-free survival. Secondary outcomes were all-cause mortality, Ureaplasma clearance, physiological bronchopulmonary dysplasia (BPD) at 36 weeks' postmenstrual age, comorbidities of prematurity and duration of respiratory support. RESULTS One hundred and twenty-one randomised participants (azithromycin: n=60; placebo: n=61) were included in the intent-to-treat analysis (mean gestational age 26.2±1.4 weeks). Forty-four of 121 participants (36%) were Ureaplasma positive (azithromycin: n=19; placebo: n=25). Ureaplasma-free survival was 55/60 (92% (95% CI 82% to 97%)) for azithromycin compared with 37/61 (61% (95% CI 48% to 73%)) for placebo. Mortality was similar comparing the two treatment groups (5/60 (8%) vs 6/61 (10%)). Azithromycin effectively eradicated Ureaplasma in all azithromycin-assigned colonised infants, but 21/25 (84%) Ureaplasma-colonised participants receiving placebo were culture positive at one or more follow-up timepoints. Most of the neonatal mortality and morbidity was concentrated in 21 infants with lower respiratory tract Ureaplasma colonisation. In a subgroup analysis, physiological BPD-free survival was 5/10 (50%) (95% CI 19% to 81%) among azithromycin-assigned infants with lower respiratory tract Ureaplasma colonisation versus 2/11 (18%) (95% CI 2% to 52%) in placebo-treated infants. CONCLUSION A 3-day azithromycin regimen effectively eradicated respiratory tract Ureaplasma colonisation in this study. TRIAL REGISTRATION NUMBER NCT01778634.
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Affiliation(s)
- Rose Marie Viscardi
- Department of Pediatrics, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Michael L Terrin
- Department of Epidemiology and Preventive Medicine, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Laurence S Magder
- Department of Epidemiology and Preventive Medicine, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Natalie L Davis
- Department of Pediatrics, University of Maryland Baltimore, Baltimore, Maryland, USA
| | - Susan J Dulkerian
- Department of Pediatrics, University of Maryland School of Medicine, Baltimore, Maryland, USA
| | - Ken B Waites
- Department of Pathology, University of Alabama at Birmingham, Birmingham, Alabama, USA
| | | | - David A Kaufman
- Department of Pediatrics, University of Virginia School of Medicine, Charlottesville, Virginia, USA
| | - Pamela Donohue
- Department of Pediatrics, Johns Hopkins Medicine, Baltimore, Maryland, USA
| | - Deborah J Tuttle
- Department of Pediatrics, Christiana Care Health System, Newark, Delaware, USA
| | - Jorn-Hendrik Weitkamp
- Department of Pediatrics, Vanderbilt University Medical Center, Nashville, Tennessee, USA
| | - Hazem E Hassan
- University of Maryland School of Pharmacy, Baltimore, Maryland, USA
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Abstract
The tracheal aspirate (TA) culture is commonly ordered in the NICU, but it has low sensitivity and specificity, limited by contamination. Interpretation of a TA culture out of context can lead to antibiotic overuse, which should be avoided. Clinicians should practice caution in the diagnosis of congenital pneumonia and use newer, published approaches to the diagnosis of ventilator-associated pneumonia in neonates. A subset of neonatal patients with risk factors of maternal fever or chorioamnionitis requiring intubation may benefit from TA culture performed within 12 hours after birth, to help identify an organism when blood culture may be negative, and tailor antimicrobial therapies. The more invasive, but more sensitive, technique of nonbronchoscopic bronchoalveolar lavage should be considered in older infants when bacterial isolation from the lower respiratory tract is necessary, because TA culture cannot distinguish between colonization and infection in that population.
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Affiliation(s)
- Colleen C Claassen
- Division of Neonatal-Perinatal Medicine, Department of Pediatrics, Saint Louis University, St Louis, MO
| | - William J Keenan
- Division of Neonatal-Perinatal Medicine, Department of Pediatrics, Saint Louis University, St Louis, MO
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Wagner BD, Sontag MK, Harris JK, Miller JI, Morrow L, Robertson CE, Stephens M, Poindexter BB, Abman SH, Mourani PM. Airway Microbial Community Turnover Differs by BPD Severity in Ventilated Preterm Infants. PLoS One 2017; 12:e0170120. [PMID: 28129336 PMCID: PMC5271346 DOI: 10.1371/journal.pone.0170120] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2016] [Accepted: 12/29/2016] [Indexed: 12/19/2022] Open
Abstract
Preterm birth exposes the developing lung to an environment with direct exposure to bacteria, often facilitated by endotracheal intubation. Despite evidence linking bacterial infections to the pathogenesis of bronchopulmonary dysplasia (BPD), systematic studies of airway microbiota are limited. The objective was to identify specific patterns of the early respiratory tract microbiome from tracheal aspirates of mechanically ventilated preterm infants that are associated with the development and severity of BPD. Infants with gestational age ≤34 weeks, and birth weight 500-1250g were prospectively enrolled. Mechanically ventilated infants had tracheal aspirate samples collected at enrollment, 7, 14, and 21 days of age. BPD was determined by modified NIH criteria with oxygen reduction tests; infants without BPD were excluded due to low numbers. Aspirates were processed for bacterial identification by 16S rRNA sequencing, and bacterial load by qPCR. Cross-sectional analysis was performed using 7 day samples and longitudinal analysis was performed from subjects with at least 2 aspirates. Microbiome analysis was performed on tracheal aspirates from 152 infants (51, 49, and 52 with mild, moderate, and severe BPD, respectively). Seventy-nine of the infants were included in the cross-sectional analysis and 94 in the longitudinal. Shannon Diversity, bacterial load, and relative abundance of individual taxa were not strongly associated with BPD status. Longitudinal analysis revealed that preterm infants who eventually developed severe BPD exhibited greater bacterial community turnover with age, acquired less Staphylococcus in the first days after birth, and had higher initial relative abundance of Ureaplasma. In conclusion, longitudinal changes in the airway microbial communities of mechanically ventilated preterm infants may be associated with BPD severity, whereas cross-sectional analysis of airway ecology at 7 days of age did not reveal an association with BPD severity. Further evaluation is necessary to determine whether the observed longitudinal changes are causal or in response to clinical management or other factors that lead to BPD.
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Affiliation(s)
- Brandie D. Wagner
- Department of Biostatistics, Colorado School of Public Health, University of Colorado, Aurora, Colorado, United States of America
- Section of Pulmonary, Department of Pediatrics, School of Medicine, University of Colorado, Aurora, Colorado, United States of America
| | - Marci K. Sontag
- Department of Epidemiology, Colorado School of Public Health, University of Colorado Denver, Aurora, Colorado, United States of America
| | - J. Kirk Harris
- Section of Pulmonary, Department of Pediatrics, School of Medicine, University of Colorado, Aurora, Colorado, United States of America
| | - Joshua I. Miller
- Department of Epidemiology, Colorado School of Public Health, University of Colorado Denver, Aurora, Colorado, United States of America
| | - Lindsey Morrow
- Department of Biostatistics, Colorado School of Public Health, University of Colorado, Aurora, Colorado, United States of America
| | - Charles E. Robertson
- Section of Infectious Disease, Department of Medicine, School of Medicine, University of Colorado, Aurora, Colorado, United States of America
| | - Mark Stephens
- Section of Pulmonary, Department of Pediatrics, School of Medicine, University of Colorado, Aurora, Colorado, United States of America
| | - Brenda B. Poindexter
- Perinatal Institute, Cincinnati Children’s Hospital Medical Center, Cincinnati, Ohio, United States of America
| | - Steven H. Abman
- Section of Pulmonary, Department of Pediatrics, School of Medicine, University of Colorado, Aurora, Colorado, United States of America
- The Pediatric Heart-Lung Center, Department of Pediatrics, School of Medicine, University of Colorado, Aurora, Colorado, United States of America
| | - Peter M. Mourani
- The Pediatric Heart-Lung Center, Department of Pediatrics, School of Medicine, University of Colorado, Aurora, Colorado, United States of America
- Section of Critical Care Medicine, Department of Pediatrics, School of Medicine, University of Colorado, Aurora, Colorado, United States of America
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Abstract
Bronchopulmonary dysplasia is the most common morbidity among surviving premature infants. Injury to the developing lung is the result of the interaction between a susceptible host and a number of contributing factors such as mechanical ventilation and infection. The resulting persistent impairment of pulmonary function and need for ongoing therapy are the underlying characteristics of bronchopulmonary dysplasia. Important insights into the pathogenesis of bronchopulmonary dysplasia have led to numerous therapies and preventive approaches. Although significant progress has been made, in order to further affect the incidence and severity of the disease, we need to further study (a) the genetically determined predisposing factors, (b) the relative contribution of the various pathogenetic pathways, and, most important, (c) how to best translate the knowledge gained from these studies into effective clinical approaches.
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Affiliation(s)
- Helen Christou
- Division of Newborn Medicine, Children's Hospital Boston, Harvard Medical School, Boston, MA 02115, USA.
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Viscardi RM, Kallapur SG. Role of Ureaplasma Respiratory Tract Colonization in Bronchopulmonary Dysplasia Pathogenesis: Current Concepts and Update. Clin Perinatol 2015; 42:719-38. [PMID: 26593075 PMCID: PMC4662049 DOI: 10.1016/j.clp.2015.08.003] [Citation(s) in RCA: 64] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Respiratory tract colonization with the genital mycoplasma species Ureaplasma parvum and Ureaplasma urealyticum in preterm infants is a significant risk factor for bronchopulmonary dysplasia (BPD). Recent studies of the ureaplasmal genome, animal infection models, and human infants have provided a better understanding of specific virulence factors, pathogen-host interactions, and variability in genetic susceptibility that contribute to chronic infection, inflammation, and altered lung development. This review provides an update on the current evidence supporting a causal role of ureaplasma infection in BPD pathogenesis. The current status of antibiotic trials to prevent BPD in Ureaplasma-infected preterm infants is also reviewed.
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Affiliation(s)
- Rose Marie Viscardi
- Department of Pediatrics, University of Maryland School of Medicine, 110 South Paca Street, 8th Floor, Baltimore, MD 21093, USA.
| | - Suhas G Kallapur
- Division of Neonatology, Cincinnati Children's Hospital Medical Center, University of Cincinnati, 3333, Burnet Avenue, Cincinnati, OH 45229, USA
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Resch B, Gutmann C, Reiterer F, Luxner J, Urlesberger B. Neonatal Ureaplasma urealyticum colonization increases pulmonary and cerebral morbidity despite treatment with macrolide antibiotics. Infection 2015; 44:323-7. [PMID: 26518581 DOI: 10.1007/s15010-015-0858-7] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2015] [Accepted: 10/17/2015] [Indexed: 11/29/2022]
Abstract
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.
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Affiliation(s)
- Bernhard Resch
- Research Unit for Neonatal Infectious Diseases and Epidemiology, Medical University of Graz, Graz, Austria. .,Division of Neonatology, Department of Pediatrics, Medical University of Graz, Auenbruggerplatz 34/2, 8036, Graz, Austria.
| | - C Gutmann
- Research Unit for Neonatal Infectious Diseases and Epidemiology, Medical University of Graz, Graz, Austria
| | - F Reiterer
- Division of Neonatology, Department of Pediatrics, Medical University of Graz, Auenbruggerplatz 34/2, 8036, Graz, Austria
| | - J Luxner
- Institute for Hygiene, Microbiology and Environmental Medicine, Medical University of Graz, Graz, Austria
| | - B Urlesberger
- Division of Neonatology, Department of Pediatrics, Medical University of Graz, Auenbruggerplatz 34/2, 8036, Graz, Austria
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8
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Acosta EP, Grigsby PL, Larson KB, James AM, Long MC, Duffy LB, Waites KB, Novy MJ. Transplacental transfer of Azithromycin and its use for eradicating intra-amniotic ureaplasma infection in a primate model. J Infect Dis 2014; 209:898-904. [PMID: 24179112 PMCID: PMC3935474 DOI: 10.1093/infdis/jit578] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2013] [Accepted: 09/20/2013] [Indexed: 11/14/2022] Open
Abstract
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.
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Affiliation(s)
| | - Peta L. Grigsby
- Oregon National Primate Research Center
- Division of Reproductive and Developmental Sciences
- Department of Obstetrics and Gynecology, Oregon Health and Science University, Beaverton
| | | | | | | | - Lynn B. Duffy
- Department of Pathology, University of Alabama at Birmingham
| | - Ken B. Waites
- Department of Pathology, University of Alabama at Birmingham
| | - Miles J. Novy
- Oregon National Primate Research Center
- Division of Reproductive and Developmental Sciences
- Department of Obstetrics and Gynecology, Oregon Health and Science University, Beaverton
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Ureaplasma, bronchopulmonary dysplasia, and azithromycin in European neonatal intensive care units: a survey. Sci Rep 2014; 4:4076. [PMID: 24518104 PMCID: PMC5379254 DOI: 10.1038/srep04076] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2013] [Accepted: 01/27/2014] [Indexed: 11/08/2022] Open
Abstract
A survey was set up to gauge the opinions of neonatologists on the role of Ureaplasma in bronchopulmonary dysplasia (BPD) development, the use of azithromycin for BPD prevention, and the factors influencing azithromycin use in European neonatal intensive care units (NICUs). 167 NICUs participated in the survey, representing 28 European countries. For respondents, the two major perceived risk factors for BPD were prematurity of <28 weeks and high oxygen requirements. Only 38% of NICUs had a protocol for BPD prevention and 47% routinely tested for Ureaplasma. In cases of infection, macrolides were the first choice. Most (78%) NICUs were interested in participating in a trial evaluating azithromycin safety and efficacy in reducing BPD rates. Opinions and clinical practice varied between European neonatal units, and differences in Ureaplasma treatment and prevention of BPD highlight the need for further azithromycin evaluation and for improved therapeutic knowledge in preterms.
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Abstract
The genital mycoplasma species, Ureaplasma parvum and Ureaplasma urealyticum are the most common organisms isolated from infected amniotic fluid and placentas, and they contribute to adverse pregnancy outcomes including preterm birth and neonatal morbidities. In our institution, almost half of the preterm infants of less than 32 weeks gestation are Ureaplasma-positive in one or more compartment (respiratory, blood and/or cerebrospinal fluid), indicating that these organisms are the most common pathogens affecting this population. This review will focus on the compelling epidemiological and experimental evidence linking perinatal Ureaplasma species exposure to important morbidities of prematurity, such as bronchopulmonary dysplasia, intraventricular haemorrhage and necrotising enterocolitis.
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Affiliation(s)
- Rose Marie Viscardi
- Department of Pediatrics, University of Maryland School of Medicine, Baltimore, MD
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Role of biofilm formation in Ureaplasma antibiotic susceptibility and development of bronchopulmonary dysplasia in preterm neonates. Pediatr Infect Dis J 2013; 32:394-8. [PMID: 23114371 PMCID: PMC3600059 DOI: 10.1097/inf.0b013e3182791ae0] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
BACKGROUND Ureaplasma respiratory tract colonization is a risk factor for bronchopulmonary dysplasia (BPD) in preterm infants, but whether Ureaplasma isolates from colonized infants can form biofilms is unknown. We hypothesized that Ureaplasma isolates vary in capacity to form biofilms that contribute to their antibiotic resistance and ability to evade host immune responses. Study objectives were to (1) determine the ability of Ureaplasma isolates from preterm neonates to form biofilms in vitro; (2) compare the susceptibility of the sessile and planktonic organisms to azithromycin (AZI) and erythromycin; and (3) determine the relationship of biofilm-forming capacity in Ureaplasma isolates and the risk for BPD. METHODS Forty-three clinical isolates from preterm neonates and 5 American Tissue Culture Collection strains were characterized for their capacity to form biofilms in vitro, and antibiotic susceptibility was performed on each isolate prebiofilm and postbiofilm formation. RESULTS Forty-one (95%) clinical and 4 of 5 (80%) American Tissue Culture Collection isolates formed biofilms. All isolates were more susceptible to AZI (minimum inhibitory concentration, MIC50 2 µg/mL) than erythromycin (MIC50 4 µg/mL), and biofilm formation did not significantly affect antibiotic susceptibility for the 2 tested antibiotics. The MIC50 and minimum biofilm inhibitory concentrations (MBIC50) for Ureaplasma urealyticum clinical isolates for AZI were higher than for MIC50 and MBIC50 for Ureaplasma parvum isolates. There were no differences in MIC or MBICs among isolates from BPD infants and non-BPD infants. CONCLUSIONS Capacity to form biofilms is common among Ureaplasma spp. isolates, but biofilm formation did not impact MICs for AZI or erythromycin.
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Azithromycin to prevent bronchopulmonary dysplasia in ureaplasma-infected preterm infants: pharmacokinetics, safety, microbial response, and clinical outcomes with a 20-milligram-per-kilogram single intravenous dose. Antimicrob Agents Chemother 2013; 57:2127-33. [PMID: 23439637 DOI: 10.1128/aac.02183-12] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Ureaplasma respiratory tract colonization is associated with bronchopulmonary dysplasia (BPD) in preterm infants. Previously, we demonstrated that a single intravenous (i.v.) dose of azithromycin (10 mg/kg of body weight) is safe but inadequate to eradicate Ureaplasma spp. in preterm infants. We performed a nonrandomized, single-arm open-label study of the pharmacokinetics (PK) and safety of intravenous 20-mg/kg single-dose azithromycin in 13 mechanically ventilated neonates with a gestational age between 24 weeks 0 days and 28 weeks 6 days. Pharmacokinetic data from 25 neonates (12 dosed with 10 mg/kg i.v. and 13 dosed with 20 mg/kg i.v.) were analyzed using a population modeling approach. Using a two-compartment model with allometric scaling of parameters on body weight (WT), the population PK parameter estimates were as follows: clearance, 0.21 liter/h × WT(kg)(0.75) [WT(kg)(0.75) indicates that clearance was allometrically scaled on body weight (in kilograms) with a fixed exponent of 0.75]; intercompartmental clearance, 2.1 liters/h × WT(kg)(0.75); central volume of distribution (V), 1.97 liters × WT (kg); and peripheral V, 17.9 liters × WT (kg). There was no evidence of departure from dose proportionality in azithromycin exposure over the tested dose range. The calculated area under the concentration-time curve over 24 h in the steady state divided by the MIC90 (AUC24/MIC90) for the single dose of azithromycin (20 mg/kg) was 7.5 h. Simulations suggest that 20 mg/kg for 3 days will maintain azithromycin concentrations of >MIC50 of 1 μg/ml for this group of Ureaplasma isolates for ≥ 96 h after the first dose. Azithromycin was well tolerated with no drug-related adverse events. One of seven (14%) Ureaplasma-positive subjects and three of six (50%) Ureaplasma-negative subjects developed physiologic BPD. Ureaplasma was eradicated in all treated Ureaplasma-positive subjects. Simulations suggest that a multiple-dose regimen may be efficacious for microbial clearance, but the effect on BPD remains to be determined.
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Gibbs K, Holzman IR. Endotracheal tube: friend or foe? Bacteria, the endotracheal tube, and the impact of colonization and infection. Semin Perinatol 2012. [PMID: 23177805 DOI: 10.1053/j.semperi.2012.06.008] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
The microbiology of the endotracheal tube culture plays a role in diagnosing a variety of diseases in the newborn intensive care unit, including subglottic stenosis, bronchopulmonary dysplasia, and ventilator-associated pneumonia. Bacterial production of a biofilm that coats the endotracheal tube acts as a reservoir for infection, prevents eradication, and may play a role in the development of subglottic stenosis. The diagnosis of ventilator-associated pneumonia is limited by the CDC definition as well as currently available diagnostic methods. Biomarkers could aid in differentiating colonization from infection, but are not available to most clinicians. The etiology of ventilator-associated pneumonia is often polymicrobial. Failure to differentiate colonization from infection results in unnecessary prescription of antibiotics, which could contribute to antimicrobial resistance. Measures to prevent ventilator-associated pneumonia have been described, primarily in the adult population.
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Affiliation(s)
- Kathleen Gibbs
- Division of Newborn Medicine, Department of Pediatrics, Mount Sinai School of Medicine, New York, NY 10029, USA.
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14
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Weisman LE, Leeming AH, Kong L. Appropriate antibiotic therapy improves Ureaplasma sepsis outcome in the neonatal mouse. Pediatr Res 2012; 72:502-6. [PMID: 22907617 DOI: 10.1038/pr.2012.115] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
BACKGROUND Ureaplasma causes sepsis in human neonates. Although erythromycin has been the standard treatment, it is not always effective. No published reports have evaluated Ureaplasma sepsis in a neonatal model. We hypothesized that appropriate antibiotic treatment improves Ureaplasma sepsis in a neonatal mouse model. METHODS Two ATCC strains and two clinical strains of Ureaplasma were evaluated in vitro for antibiotic minimum inhibitory concentration (MIC). In addition, FVB albino mice pups infected with Ureaplasma were randomly assigned to saline, erythromycin, or azithromycin therapy and survival, quantitative blood culture, and growth were evaluated. RESULTS MICs ranged from 0.125 to 62.5 µg/ml and 0.25 to 1.0 µg/ml for erythromycin and azithromycin, respectively. The infecting strain and antibiotic selected for treatment appeared to affect survival and bacteremia, but only the infecting strain affected growth. Azithromycin improved survival and bacteremia against each strain, whereas erythromycin was effective against only one of four strains. CONCLUSION We have established a neonatal model of Ureaplasma sepsis and observed that treatment outcome is related to infecting strain and antibiotic treatment. We speculate that appropriate antibiotic selection and dosing are required for effective treatment of Ureaplasma sepsis in neonates, and this model could be used to further evaluate these relationships.
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Affiliation(s)
- Leonard E Weisman
- Department of Pediatrics, Baylor College of Medicine, Houston, Texas, USA.
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Ozdemir R, Erdeve O, Dizdar EA, Oguz SS, Uras N, Saygan S, Karabulut E, Dilmen U. Clarithromycin in preventing bronchopulmonary dysplasia in Ureaplasma urealyticum-positive preterm infants. Pediatrics 2011; 128:e1496-501. [PMID: 22123897 DOI: 10.1542/peds.2011-1350] [Citation(s) in RCA: 58] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
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.
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Affiliation(s)
- Ramazan Ozdemir
- Zekai Tahir Burak Maternity Teaching Hospital, Ankara, Turkey.
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16
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Mourani PM, Harris JK, Sontag MK, Robertson CE, Abman SH. Molecular identification of bacteria in tracheal aspirate fluid from mechanically ventilated preterm infants. PLoS One 2011; 6:e25959. [PMID: 22016793 PMCID: PMC3189942 DOI: 10.1371/journal.pone.0025959] [Citation(s) in RCA: 56] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2011] [Accepted: 09/14/2011] [Indexed: 12/21/2022] Open
Abstract
BACKGROUND Despite strong evidence linking infections to the pathogenesis of bronchopulmonary dysplasia (BPD), limitations of bacterial culture methods have precluded systematic studies of airway organisms relative to disease outcomes. Application of molecular bacterial identification strategies may provide new insight into the role of bacterial acquisition in the airways of preterm infants at risk for BPD. METHODS Serial (within 72 hours, 7, 14, and 21 days of life) tracheal aspirate samples were collected from 10 preterm infants with gestational age ≤34 weeks at birth, and birth weight of 500-1250 g who required mechanical ventilation for at least 21 days. Samples were analyzed by quantitative real time PCR assays for total bacterial load and by pyrosequencing for bacterial identification. RESULTS Subjects were diagnosed with mild (1), moderate (3), or severe (5) BPD. One patient died prior to determination of disease severity. 107,487 sequences were analyzed, with mean of 3,359 (range 1,724-4,915) per sample. 2 of 10 samples collected <72 hours of life contained adequate bacterial DNA for successful sequence analysis, one of which was from a subject exposed to chorioamnionitis. All other samples exhibited bacterial loads >70copies/reaction. 72 organisms were observed in total. Seven organisms represented the dominant organism (>50% of total sequences) in 31/32 samples with positive sequences. A dominant organism represented>90% of total sequences in 13 samples. Staphylococcus, Ureaplasmaparvum, and Ureaplasmaurealyticum were the most frequently identified dominant organisms, but Pseudomonas, Enterococcus, and Escherichia were also identified. CONCLUSIONS Early bacterial colonization with diverse species occursafter the first 3 days of life in the airways of intubated preterm infants, and can be characterized by bacterial load and marked species diversity. Molecular identification of bacteria in the lower airways of preterm infants has the potential to yield further insight into the pathogenesis of BPD.
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Affiliation(s)
- Peter M Mourani
- Pediatric Heart Lung Center, Department of Pediatrics, University of Colorado Denver, School of Medicine, Aurora, Colorado, United States of America.
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17
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Ballard HO, Shook LA, Bernard P, Anstead MI, Kuhn R, Whitehead V, Grider D, Crawford TN, Hayes D. Use of azithromycin for the prevention of bronchopulmonary dysplasia in preterm infants: a randomized, double-blind, placebo controlled trial. Pediatr Pulmonol 2011; 46:111-8. [PMID: 20963840 DOI: 10.1002/ppul.21352] [Citation(s) in RCA: 73] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/17/2010] [Revised: 07/08/2010] [Accepted: 07/16/2010] [Indexed: 01/01/2023]
Abstract
OBJECTIVE Since preventive therapies for bronchopulmonary dysplasia (BPD) are limited we treated preterm infants with azithromycin to decrease the incidence of BPD. METHODS Infants less than 1,250 g birth weight were randomized to azithromycin or placebo within 12 hr of beginning mechanical ventilation and within 72 hr of birth. The treatment group received azithromycin 10 mg/kg/day for 7 days followed by 5 mg/kg/day for a maximum of 6 weeks. Aspirates were collected during the study to assay for Ureaplasma. The primary endpoints were incidence of BPD or mortality. (Clinical Trials Identifier: NCT00319956.) RESULTS A total of 220 infants were enrolled (n=111 azithromycin, and 109 placebo). Mortality was 18% for the azithromycin group versus 22% for the placebo group (P = 0.45). Incidence of BPD was 76% for the azithromycin group versus 84% for the placebo group (P=0.2). The multiple logistic regression analysis demonstrated an odds ratio of 0.46 decrease in the chance of developing BPD or death for the azithromycin group, but was not statistically significant. The incidence of BPD in the Ureaplasma subgroup was 73% in the azithromycin group versus 94% in the placebo group (P=0.03). Analysis of patients in the Ureaplasma subgroup only, using the exact logistic model demonstrated a decrease in BPD or death in the azithromycin group with an estimated odds ratio of 0.026 (0.001-0.618, 95% confidence interval). CONCLUSIONS Routine use of azithromycin therapy for the prevention of BPD cannot be recommended. The early treatment of Ureaplasma colonized/infected patients might be beneficial, but a larger multi-centered trial is required to assess this more definitively.
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18
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Hassan HE, Othman AA, Eddington ND, Duffy L, Xiao L, Waites KB, Kaufman DA, Fairchild KD, Terrin ML, Viscardi RM. Pharmacokinetics, safety, and biologic effects of azithromycin in extremely preterm infants at risk for ureaplasma colonization and bronchopulmonary dysplasia. J Clin Pharmacol 2010; 51:1264-75. [PMID: 21098694 DOI: 10.1177/0091270010382021] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Ureaplasma spp. respiratory tract colonization is a significant risk factor for bronchopulmonary dysplasia (BPD), a chronic lung disorder in preterm infants. As an initial step preparatory to future clinical trials to evaluate the clinical efficacy of azithromycin to prevent BPD, the authors characterized the pharmacokinetics, safety, and biological effects of a single intravenous dose of azithromycin (10 mg/kg) in preterm neonates (n = 12) 24 to 28 weeks gestation at risk for Ureaplasma infection and BPD. A 2-compartment structural model with the clearance and volume of peripheral compartment (V2) allometrically scaled on body weight (WT) best described the pharmacokinetics of azithromycin in preterm neonates. The estimated parameters were clearance [0.18 L/h × WT(kg)(0.75)], intercompartmental clearance [1.0 L/h], volume of distribution of central compartment [0.93 L], and V2 [14.2 L × WT(kg)]. There were no serious adverse events attributed to azithromycin. A single dose of azithromycin did not suppress inflammatory cytokines or myeloperoxidase activity in tracheal aspirates. These results demonstrated the safety of azithromycin and developed a pharmacokinetic model that is useful for future simulation-based clinical trials for eradicating Ureaplasma and preventing BPD in preterm neonates.
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Affiliation(s)
- Hazem E Hassan
- Pharmacokinetics and Biopharmaceutics Laboratory, Department of Pharmaceutical Sciences, School of Pharmacy, University of Maryland, Baltimore, Maryland, USA
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19
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Abstract
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.
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Affiliation(s)
- Rose M. Viscardi
- Department of Pediatrics, University of Maryland School of Medicine, Baltimore, MD
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20
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Congenital and opportunistic infections: Ureaplasma species and Mycoplasma hominis. Semin Fetal Neonatal Med 2009; 14:190-9. [PMID: 19109084 DOI: 10.1016/j.siny.2008.11.009] [Citation(s) in RCA: 125] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
There is strong evidence from clinical and experimental animal studies that ureaplasmas can invade the amnionic sac and induce an inflammatory response resulting in chorioamnionitis, preterm labor and neonatal lung injury. The ability of Ureaplasma spp. and Mycoplasma hominis to cause pneumonia, bacteremia, and meningitis in newborns can no longer be questioned. The association of Ureaplasma spp. with bronchopulmonary dysplasia has been supported by the majority of observational studies, but proof of causality is still lacking. The availability of molecular diagnostic technologies has enabled the designation of the two Ureaplasma biovars as individual species, but additional work must be done to establish whether there is differential pathogenicity between the Ureaplasma spp. or among their respective serovars. Future investigations to prevent prematurity should be directed toward identification and localization of specific micro-organisms combined with targeted antibiotic trials to determine whether such interventions can improve long-term infant outcomes.
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Walls SA, Kong L, Leeming HA, Placencia FX, Popek EJ, Weisman LE. Antibiotic prophylaxis improves Ureaplasma-associated lung disease in suckling mice. Pediatr Res 2009; 66:197-202. [PMID: 19390479 DOI: 10.1203/pdr.0b013e3181aabd34] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Ureaplasma infection is associated with increased lung disease in high-risk neonates. Our goal was to determine the impact of antibiotic prophylaxis on Ureaplasma and oxygen-induced lung disease in newborn mice. In animal model development and prophylaxis experiments, pups were randomly assigned to either 0.8 or 0.21 inspired oxygen concentration [fraction of inspired oxygen (FiO2)] from 1 to 14 d of age and either Ureaplasma or 10 B media daily from 1 to 3 d. All pups were observed for growth and survival. Surviving pups had culture and PCR evaluated for blood, bronchoalveolar lavage, and lung, and lung weights, pathology, morphometry, histology, and immunohistochemistry were determined. In prophylaxis experiments, erythromycin, azithromycin, or normal saline was given for the first 3 d, and minimum inhibitory concentration and pharmacokinetics were determined. In model development, 0.8 FiO2 and Ureaplasma infection survival and growth were significantly decreased and lung edema and inflammation were significantly increased. In prophylaxis experiments, we observed significantly improved survival and growth with azithromycin versus normal saline controls, whereas erythromycin was not significantly different from controls, and decreased inflammatory response with azithromycin versus normal saline and erythromycin. In a neonatal mouse model of Ureaplasma and oxygen-induced lung disease, appropriate antibiotic prophylaxis improves survival and morbidity and decreases lung inflammation.
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Affiliation(s)
- Scott A Walls
- Department of Pediatrics, Baylor College of Medicine, Texas Children's Hospital, Houston, Texas 77030, USA
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22
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Maxwell NC, Nuttall D, Kotecha S. Does Ureaplasma spp. cause chronic lung disease of prematurity: ask the audience? Early Hum Dev 2009; 85:291-6. [PMID: 19144476 PMCID: PMC2681047 DOI: 10.1016/j.earlhumdev.2008.12.002] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/23/2008] [Revised: 12/01/2008] [Accepted: 12/02/2008] [Indexed: 12/02/2022]
Abstract
Ureaplasma has long been implicated in the pathogenesis of both preterm labour and neonatal morbidity, particularly chronic lung disease of prematurity (CLD), but despite numerous studies, reviews and meta-analyses, its exact role remains unclear. Many papers call for a definitive randomised control trial to determine if eradication of pulmonary Ureaplasma decreases the rates of CLD but few address in detail the obstacles to an adequately powered clinical trial. We review the evidence for Ureaplasma as a causative agent in CLD, asking why a randomised control trial has not been performed. We surveyed the opinions of senior neonatologists in the UK on whether they felt that there was sufficient evidence for Ureaplasma either causing or not causing CLD and whether a definitive trial was needed, as well as their views on the design of such a trial. Additionally, we ascertained current practice with respect to Ureaplasma detection in preterm neonates in the UK. There is clear support for an adequately powered randomised controlled clinical trial by senior neonatologists in the UK. There are no reasons why a definitive trial cannot be conducted especially as the appropriate samples, and methods to culture or identify the organism by PCR are already available.
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Affiliation(s)
- Nicola C. Maxwell
- Department of Child Health, Cardiff University, Cardiff CF14 4XN, United Kingdom
| | - Diane Nuttall
- Department of Child Health, Cardiff University, Cardiff CF14 4XN, United Kingdom
| | - Sailesh Kotecha
- Corresponding author. Department of Child Health, Cardiff University, Heath Park, Cardiff CF14 4XN, United Kingdom. Tel.: +44 29 2074 4187; fax: +44 29 2074 4283.
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23
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Greenough A. Emerging drugs for the prevention of bronchopulmonary dysplasia. Expert Opin Emerg Drugs 2008; 13:537-46. [PMID: 18764728 DOI: 10.1517/14728214.13.3.537] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
BACKGROUND Bronchopulmonary dysplasia (BPD) is a common adverse outcome of very premature birth and is associated with chronic respiratory morbidity. OBJECTIVE To determine if there were preventative therapies proven safe and efficacious in appropriately powered randomised trials. METHODS A literature review was undertaken. RESULTS Systemically administered corticosteroids, if given in the first 2 weeks, do significantly reduce BPD but have serious side effects. Vitamin A also reduces BPD, but has side effects, and further investigation is needed to identify the safest dosage regimen. There are, however, promising therapies that include antioxidants, low-dose nitric oxide and methylxanthines. CONCLUSION Further work is necessary to identify safe and effective preventative drugs for BPD.
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Affiliation(s)
- Anne Greenough
- Division of Asthma, Allergy and Lung Biology, King's College Hospital, Denmark Hill, London, SE5 9RS, UK.
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24
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Twenty percent of very preterm neonates (23-32 weeks of gestation) are born with bacteremia caused by genital Mycoplasmas. Am J Obstet Gynecol 2008; 198:1-3. [PMID: 18166295 DOI: 10.1016/j.ajog.2007.11.031] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2007] [Accepted: 11/16/2007] [Indexed: 11/21/2022]
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25
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Abstract
Infection with the ureaplasmas may occur in utero or perinatally in prematurely born infants. For some infants, infection with these organisms triggers a vigorous pro-inflammatory response in the lungs and increases the risk of developing bronchopulmonary dysplasia (BPD). At present, there is insufficient evidence from clinical trials to determine whether antibiotic treatment of Ureaplasma has any influence on the development of BPD and its comorbidities. Future investigation in the context of well-designed, adequately powered controlled clinical trials should focus on determining whether treatment of ureaplasmal infection lessens lung inflammation, decreases rates of BPD, and improves long-term, neurodevelopmental outcome.
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Affiliation(s)
- Robert L Schelonka
- Department of Pediatrics, University of Alabama at Birmingham, Birmingham, AL, USA.
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26
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Abstract
Bronchopulmonary dysplasia (BPD) is a disease of complex and multifactorial etiology and a major cause of morbidity in premature infants. Contributing factors include infection, exposure to toxic oxygen levels, and ventilator-induced lung injury, resulting in arrested lung development and impaired lung function. Several preventive and therapeutic strategies have been employed and include lung protective ventilator strategies, pharmacological and nutritional interventions. These strategies target different components and stages of the disease process, and their success has been variable. This review intends to bring together prior and current pharmacological interventions and future therapeutic modalities that appear promising in the prevention and management of BPD. Better understanding of the pathogenesis has given hope for newer treatment options. Newer studies need to be designed to assess the efficacy of combination therapies that target multiple steps of the disease process.
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Affiliation(s)
- Rajiv Baveja
- Division of Newborn Medicine, Children's Hospital Boston and Harvard Medical School, Boston, MA 02115, USA
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27
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Pinna GS, Skevaki CL, Kafetzis DA. The significance of Ureaplasma urealyticum as a pathogenic agent in the paediatric population. Curr Opin Infect Dis 2006; 19:283-9. [PMID: 16645491 DOI: 10.1097/01.qco.0000224824.73223.e7] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
PURPOSE OF REVIEW Ureaplasma urealyticum is a frequent commensal in the lower genital tract of sexually active women. It may be transmitted perinatally from the colonized mother to her offspring, often resulting in prematurity and neonatal disease. The microorganism also sustains a causative role for infectious diseases in older children. RECENT FINDINGS U. urealyticum infection can be diagnosed by culture, polymerase chain reaction, and the detection of specific antibodies. Neonatal infection has been implicated in various pathological conditions including pneumonia, chronic lung disease, central nervous system disorders, sepsis, osteomyelitis and even death. Older children may present with wheezing, pneumonitis, pertussis-like syndrome and different forms of arthritis. Large well-designed trials have demonstrated that the regular administration of antibiotics to vaginally colonized women are not beneficial in terms of preventing preterm labour. Macrolide-containing antibiotic regimens are, however, recommended for preterm premature rupture of the membranes. Erythromycin treatment of ureaplasma respiratory colonized premature infants shows no reduction in the incidence of chronic lung disease. Treatment of central nervous system infections, sepsis and arthritides includes tetracyclines, fluoroquinolones and anti-inflammatory agents, respectively. SUMMARY This review covers recent evidence concerning the role of U. urealyticum as a pathogen during childhood. It also includes an evaluation of contemporary diagnostic techniques and optimal therapeutic approaches.
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Affiliation(s)
- Georgia S Pinna
- Department of Microbiology, Evagelismos General Hospital, Athens, Greece
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28
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Prävention und Therapie der bronchopulmonalen Dysplasie. Monatsschr Kinderheilkd 2005. [DOI: 10.1007/s00112-005-1259-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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29
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Abstract
The genital mycoplasmas represent a complex and unique group of microorganisms that have been associated with a wide array of infectious diseases in adults and infants. The lack of conclusive knowledge regarding the pathogenic potential of Mycoplasma and Ureaplasma spp. in many conditions is due to a general unfamiliarity of physicians and microbiology laboratories with their fastidious growth requirements, leading to difficulty in their detection; their high prevalence in healthy persons; the poor design of research studies attempting to base association with disease on the mere presence of the organisms in the lower urogenital tract; the failure to consider multifactorial aspects of diseases; and considering these genital mycoplasmas only as a last resort. The situation is now changing because of a greater appreciation of the genital mycoplasmas as perinatal pathogens and improvements in laboratory detection, particularly with regard to the development of powerful molecular nucleic acid amplification tests. This review summarizes the epidemiology of genital mycoplasmas as causes of neonatal infections and premature birth; evidence linking ureaplasmas with bronchopulmonary dysplasia; recent changes in the taxonomy of the genus Ureaplasma; the neonatal host response to mycoplasma and ureaplasma infections; advances in laboratory detection, including molecular methods; and therapeutic considerations for treatment of systemic diseases.
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Affiliation(s)
- Ken B Waites
- Department of Pathology, University of Alabama, Birmingham, Alabama 35249, USA.
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30
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Aujard Y, Maury L, Doit C, Mariani-Kurkdjian P, Baud O, Farnoux C, Bingen E. Ureaplasma urealyticum, Mycoplasma hominis et pathologiesnéonatales : Données personnelles et revue de la littérature. Arch Pediatr 2005; 12 Suppl 1:S12-8. [PMID: 15893230 DOI: 10.1016/s0929-693x(05)80004-1] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Ureaplasma urealyticum and Mycoplasma hominis colonized 20-40% of newborns and are more frequent in premature. They are responsible for localized infections such as pleural effusion, pneumopathy, adenopathy, abscess or systemic sepsis. An important hyperleukocytosis is often associated with pulmonary infections. Their responsibility, as pathogen agents, is questionable in some non bacterial meningitis. There is large controversy for their role as cofactor, in chronic lung disease (bronchopulmonary dysplasia) and periventricular leukomalacia, because of a too low number of newborns in prospective trials. Genital mycoplamas are resistant to beta lactamines. Macrolides have a good sensitivity, particularly josamycine, but Mycoplasma hominis is resistant to erythromycin. For systemic sepsis, fluoroquinolones such as ciprofloxacine have less deleterious effects than IV erythromycin.
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Affiliation(s)
- Y Aujard
- Laboratoire de microbiologie, hôpital Robert-Debré, assistance publique-hôpitaux de Paris, 48, boulevard Sérurier, 75019 Paris, France.
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31
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Kong F, Gilbert GL. Postgenomic taxonomy of human ureaplasmas -- a case study based on multiple gene sequences. Int J Syst Evol Microbiol 2005; 54:1815-1821. [PMID: 15388749 DOI: 10.1099/ijs.0.63073-0] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
In 2000, the full genome sequence of Ureaplasma parvum (previously known as Ureaplasma urealyticum) serovar 3 was released. In 2002, after prolonged debate, it was agreed that the former U. urealyticum should be divided into two species -- U. parvum and U. urealyticum. To provide additional support for this decision and improve our understanding of the relationship between these two species, the authors studied four 'core' genes or gene clusters in ATCC reference strains of all 14 serovars of U. parvum and U. urealyticum. These 'core' regions were the rRNA gene clusters, the EF-Tu genes (tuf), urease gene clusters and multiple-banded antigen genes (mba). The known U. parvum genome sequences (GenBank accession no. NC_002162) were used as reference. DNA insertions and deletions (indels) were found in all of the gene regions studied, except tuf, but they were found only between, not within, the two species. An incidental finding was that there was inter-copy heterogeneity for rRNA gene cluster sequences. Sequence analysis (sequence heterogeneity and especially indels) of all four selected targets consistently supported the separation of human ureaplasmas into two species. Except for multiple-banded antigen, there was less heterogeneity in amino acid sequences of proteins, between species, than in the nucleic acid sequences of the corresponding genes. The degrees of heterogeneity at the 5' end of the species-specific regions of multiple-banded antigen were almost identical for both amino acid and nucleotide sequences. Analysis of the authors' results provided an interesting case study to help resolve some common problems in the use of sequence data to infer phylogenetic relationships and support taxonomic changes. It is recommended that, to avoid confusion, the new nomenclature be used for human ureaplasmas in future publications.
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MESH Headings
- Bacterial Proteins/genetics
- DNA, Bacterial/chemistry
- DNA, Bacterial/isolation & purification
- DNA, Ribosomal/chemistry
- DNA, Ribosomal/isolation & purification
- DNA, Ribosomal Spacer/chemistry
- DNA, Ribosomal Spacer/isolation & purification
- Genes, Bacterial
- Genes, rRNA/genetics
- Genetic Variation
- Humans
- Molecular Sequence Data
- Peptide Elongation Factor Tu/genetics
- Phylogeny
- RNA, Ribosomal, 16S/genetics
- RNA, Ribosomal, 23S/genetics
- RNA, Ribosomal, 5S/genetics
- Sequence Analysis, DNA
- Sequence Deletion
- Sequence Homology, Amino Acid
- Sequence Homology, Nucleic Acid
- Ureaplasma/classification
- Ureaplasma/genetics
- Urease/genetics
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Affiliation(s)
- Fanrong Kong
- Centre for Infectious Diseases and Microbiology (CIDM), Institute of Clinical Pathology and Medical Research (ICPMR), Westmead, New South Wales, Australia
| | - Gwendolyn L Gilbert
- Centre for Infectious Diseases and Microbiology (CIDM), Institute of Clinical Pathology and Medical Research (ICPMR), Westmead, New South Wales, Australia
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Abstract
The pathology of BPD has changed over time, with the old BPD characterized by airway injury, inflammation, and parenchymal fibrosis giving way to the new BPD manifesting less fibrosis but with decreased alveolar and vascular development. The pathogenesis of BPD involves factors affecting the severity and management of RDS, alterations in lung development and maturation, alveolar-vascular interactions, and extracellular matrix remodeling. These factors in pathogenesis are mediated and modulated by hyperoxic lung injury, antioxidants, NO, the pulmonary neuroendocrine system and peptide growth factors, the immune system, and various genetic polymorphisms and predispositions. Future therapeutic interventions are likely to target one or more of these abnormalities in lung development, maturation, and response to injury.
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Affiliation(s)
- Namasivayam Ambalavanan
- Division of Neonatology, Department of Pediatrics, University of Alabama at Birmingham, 620 South 20th Street, Birmingham, AL 35233, USA.
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