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Published on: November 20, 2015
Ureaplasma urealyticum, erythromycin and respiratory morbidity in high-risk preterm neonates
B Jónsson1, M Rylander, G Faxelius
1Department of Neonatology, Astrid Lindgren Children's Hospital, Karolinska Hospital and Institute, Stockholm, Sweden.
Insights
Ureaplasma urealyticum colonization in preterm infants is linked to prematurity and delivery factors. Erythromycin reduced colonization but did not significantly impact oxygen needs.
Area of Science:
- Neonatal Medicine
- Microbiology
- Pediatric Respiratory Medicine
Background:
- Ureaplasma urealyticum (Uu) colonization is a concern in very preterm infants.
- Risk factors for Uu colonization and its impact on respiratory morbidity require further investigation.
Purpose of the Study:
- To investigate Ureaplasma urealyticum colonization in infants under 30 weeks gestation.
- To assess the relationship between Uu colonization and respiratory morbidity risk factors.
- To evaluate the efficacy of erythromycin treatment for Uu colonization in this population.
Main Methods:
- Cultured endotracheal aspirate and nasopharyngeal samples for Uu in 155 ventilated preterm infants (median GA 26 weeks).
- Randomly assigned colonized infants to erythromycin treatment (40 mg/kg/d, IV or oral).
- Assessed colonization rates, gestational age, delivery factors, and oxygen requirements at 36 weeks postconceptual age.
Main Results:
- Uu colonization rate was 19% (29/155 infants).
- Uu-colonized infants had lower gestational ages and higher rates of prolonged rupture of membranes, chorioamnionitis, and vaginal delivery.
- Colonized infants required more supplemental oxygen at 36 weeks (p < 0.05).
- Erythromycin effectively reduced Uu colonization (86% negative cultures).
- No significant difference in supplemental oxygen duration between treated and untreated colonized infants.
Conclusions:
- Ureaplasma urealyticum colonization is associated with increased prematurity, prolonged rupture of membranes, chorioamnionitis, and vaginal delivery.
- Erythromycin treatment successfully reduces Uu colonization in preterm infants.
- Erythromycin treatment did not significantly alter the duration of supplemental oxygen support.
Abstract:
We investigated colonization with Ureaplasma urealyticum (Uu) in infants <30 weeks gestation and assessed the relationship to other risk factors influencing respiratory morbidity, plus the effect of treatment with erythromycin. Ventilated preterm infants [n = 155; median GA 26 (23-29) weeks] were cultured for Uu in endotracheal aspirate and nasopharynx. Colonized infants were randomly assigned to treatment with erythromycin 40 mg/kg/d, intravenously or orally. The rate of colonization was 29/155 (19%) and the Uu-colonized infants had lower mean gestational ages than the culture-negative infants (25 vs 26 weeks). For the colonized infants PROM (48% vs 12%), chorioamnionitis in the mother (46% vs 17%) and vaginal delivery (71% vs 29%) were more common. More colonized infants needed supplemental oxygen at 36 weeks' postconceptual age (p < 0.05). Erythromycin treatment was effective in reducing colonization with negative control cultures in 12/14 (86%) of treated infants. No significant differences were found between the colonized treated infants (n = 14) and those not treated (n = 14) in time with supplemental oxygen. Oxygen requirement at 36 weeks was related to lower gestational age, late appearance of PDA, late onset sepsis and signs of chorioamnionitis in the mother. We conclude that the Uu colonization is related to increasing immaturity, the presence of prolonged rupture of membranes, signs of chorioamnionitis and vaginal delivery. Treatment with erythromycin reduced colonization but did not significantly alter length of time with supplemental oxygen.
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