Characteristics and influence of Mycoplasma/Ureaplasma cultures in amniotic fluid on perinatal outcomes

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.

Amniotic fluid Gram stain and interleukin-6 can predict early-onset neonatal sepsis

AIM

To clarify whether amniotic fluid findings (Gram stain and interleukin [IL]-6 level) can predict early-onset neonatal sepsis (EONS) before delivery.

METHODS

We compared the sensitivity and specificity and the values of the area under the receiver-operating characteristic (AUROC) curve of maternal inflammatory responses and amniotic fluid findings using IL-6 and Gram stain to predict EONS. Patients who underwent amniocentesis for suspected intra-amniotic infection (IAI) after 22 weeks and 0 days of gestation and delivered on the same day at our hospital between January 2013 and December 2018 were included.

RESULTS

Out of 200 patients, EONS developed in 9 patients. The AUROC curves of maternal white blood cells count, C-reactive protein and body temperature were low (range, 0.6-0.7), whereas that of amniotic fluid IL-6 was high (0.90). Sensitivity and specificity for amniotic fluid findings were, respectively, 100% and 67% for IL-6 (cut-off value: 17.4 ng/mL) and 100% and 88% for the Gram stain; these values were superior to those of maternal inflammatory responses. When examining the accuracy of the amniotic fluid Gram stain separately before and after 34 gestation weeks, similar results were obtained. Amniotic fluid IL-6 before 34 gestation weeks showed specificity similar to that of the Gram stain; however, there were large differences in cut-off values based on gestational age.

CONCLUSION

Gram stain results of amniotic fluid can predict EONS with high sensitivity and specificity when IAI is suspected. False-negative amniotic fluid Gram stain results can be prevented by measuring amniotic fluid IL-6 simultaneously.

Ureaplasma-Driven Neuroinflammation in Neonates: Assembling the Puzzle Pieces

Ureaplasma species (spp.) are commonly regarded as low-virulence colonizers of the genitourinary tract. Intrauterine Ureaplasma infection, however, has been associated with chorioamnionitis and preterm birth. The overall impact of a neonatal Ureaplasma colonization is yet to be understood. High pathogen prevalence and frequent neurological morbidities particularly in immature preterm infants call for an assessment of the significance of Ureaplasma spp. in neonatal neuroinflammation. This narrative review summarizes clinical data, animal studies, and in vitro results to elucidate potential Ureaplasma-associated neurological morbidities as well as underlying mechanisms. Increasing evidence indicates an involvement of Ureaplasma spp. in invasive central nervous system infections, suggesting a meticulous ability of Ureaplasma spp. to interfere with immune defense mechanisms. Ultimately, Ureaplasma spp. should be considered as relevant pathogens in neonatal neuroinflammation.