Genital tract GBS and rate of histologic chorioamnionitis in patients with preterm premature rupture of membrane

Placental histopathology in preterm birth with confirmed maternal infection: A systematic literature review

Four in five neonatal deaths of preterm births occur in low and middle income countries and placental histopathology examination can help clarify the pathogenesis. Infection is known to play a significant role in preterm birth. The aim of this systematic review is to explore the association between placental histopathological abnormality and preterm birth in the presence of confirmed infection. PubMed/Medline, Scopus, Web of Science and Embase were searched using the keywords related to preterm birth, placental histopathology and infection. Titles and abstracts were screened and the full texts of eligible articles were reviewed to extract and summarise data. Of 1529 articles, only 23 studies (13 bacterial, 6 viral and 4 parasitic) were included, and they used 7 different gestational age windows, and 20 different histopathological classification systems, precluding data pooling. Despite this, histopathological chorioamnionitis, and funisitis (when examined) were commonly observed in preterm birth complicated by confirmed bacterial or viral, but not parasitic, infection. The presence of malaria parasites but not pigment in placenta was reported to increase the risk of PTB, but this finding was inconclusive. One in three studies were conducted in low and middle income countries. An array of: definitions of preterm birth subgroups, histological classification systems, histopathologic abnormalities and diagnostic methods to identify infections were reported in this systematic review. Commitment to using standardised terminology and classification of histopathological abnormalities associated with infections is needed to identify causality and potential treatment of preterm birth. Studies on preterm birth needs to occur in high burden countries and control for clinical characteristics (maternal, fetal, labor, and placental) that may have an impact on placental histopathological abnormalities.

Placental Structure in Preterm Birth Among HIV-Positive Versus HIV-Negative Women in Kenya

Background:

Preterm birth (PTB) is a major cause of infant morbidity and mortality in developing countries. Recent data suggest that in addition to Human Immunodeficiency Virus (HIV) infection, use of antiretroviral therapy (ART) increases the risk of PTB. As the mechanisms remain unexplored, we conducted this study to determine whether HIV and ART were associated with placental changes that could contribute to PTB.

Setting:

We collected and evaluated placentas from 38 HIV-positive women on ART and 43 HIV-negative women who had preterm deliveries in Nairobi, Kenya.

Methods:

Anatomical features of the placentas were examined at gross and microscopic levels. Cases were matched for gestational age and compared by the investigators who were blinded to maternal HIV serostatus.

Results:

Among preterm placentas, HIV infection was significantly associated with thrombosis (P = 0.001), infarction (P = 0.032), anomalies in cord insertion (P = 0.02), gross evidence of membrane infection (P = 0.043), and reduced placental thickness (P = 0.010). Overall, preterm placentas in both groups were associated with immature villi, syncytial knotting, villitis, and deciduitis. Features of HIV-positive versus HIV-negative placentas included significant fibrinoid deposition with villus degeneration, syncytiotrophoblast delamination, red blood cell adhesion, hypervascularity, and reduction in both surface area and perimeter of the terminal villi.

Conclusions:

These results imply that HIV infection and/or ART are associated with morphological changes in preterm placentas that contribute to delivery before 37 weeks. Hypervascularity suggests that the observed pathologies may be attributable, in part, to hypoxia. Further research to explore potential mechanisms will help elucidate the pathways that are involved perhaps pointing to interventions for decreasing the risk of prematurity among HIV-positive women.

Antibiotic administration can eradicate intra-amniotic infection or intra-amniotic inflammation in a subset of patients with preterm labor and intact membranes

BACKGROUND

Intra-amniotic infection is present in 10% of patients with an episode of preterm labor, and is a risk factor for impending preterm delivery and neonatal morbidity/mortality. Intra-amniotic inflammation is often associated with intra-amniotic infection, but is sometimes present in the absence of detectable microorganisms. Antibiotic treatment of intra-amniotic infection has traditionally been considered to be ineffective. Intra-amniotic inflammation without microorganisms has a prognosis similar to that of intra-amniotic infection.

OBJECTIVE

To determine whether antibiotics can eradicate intra-amniotic infection or intra-amniotic inflammation in a subset of patients with preterm labor and intact membranes.

MATERIALS AND METHODS

The study population consisted of women who met the following criteria: 1) singleton gestation between 20 and 34 weeks; 2) preterm labor and intact membranes; 3) transabdominal amniocentesis performed for the evaluation of the microbiologic/inflammatory status of the amniotic cavity; 4) intra-amniotic infection and/or intra-amniotic inflammation; and 5) received antibiotic treatment that consisted of ceftriaxone, clarithromycin, and metronidazole. Follow-up amniocentesis was performed in a subset of patients. Amniotic fluid was cultured for aerobic and anaerobic bacteria and genital mycoplasmas, and polymerase chain reaction was performed for Ureaplasma spp. Intra-amniotic infection was defined as a positive amniotic fluid culture or positive polymerase chain reaction, and intra-amniotic inflammation was suspected when there was an elevated amniotic fluid white blood cell count or a positive result of a rapid test for matrix metalloproteinase-8. For this study, the final diagnosis of intra-amniotic inflammation was made by measuring the interleukin-6 concentration in stored amniotic fluid (>2.6 ng/mL). These results were not available to managing clinicians. Treatment success was defined as eradication of intra-amniotic infection and/or intra-amniotic inflammation or delivery ≥37 weeks.

RESULTS

Of 62 patients with intra-amniotic infection and/or intra-amniotic inflammation, 50 received the antibiotic regimen. Of those patients, 29 were undelivered for ≥7 days and 19 underwent a follow-up amniocentesis. Microorganisms were identified by culture or polymerase chain reaction of amniotic fluid obtained at admission in 21% of patients (4/19) who had a follow-up amniocentesis, and were eradicated in 3 of the 4 patients. Resolution of intra-amniotic infection/inflammation was confirmed in 79% of patients (15/19), and 1 other patient delivered at term, although resolution of intra-amniotic inflammation could not be confirmed after a follow-up amniocentesis. Thus, resolution of intra-amniotic inflammation/infection or term delivery (treatment success) occurred in 84% of patients (16/19) who had a follow-up amniocentesis. Treatment success occurred in 32% of patients (16/50) with intra-amniotic infection/inflammation who received antibiotics. The median amniocentesis-to-delivery interval was significantly longer among women who received the combination of antibiotics than among those who did not (11.4 days vs 3.1 days: P = .04).

CONCLUSION

Eradication of intra-amniotic infection/inflammation after treatment with antibiotics was confirmed in 79% of patients with preterm labor, intact membranes, and intra-amniotic infection/inflammation who had a follow-up amniocentesis. Treatment success occurred in 84% of patients who underwent a follow-up amniocentesis and in 32% of women who received the antibiotic regimen.

Should the diagnostic criteria for suspected clinical chorioamnionitis be changed?

Purpose of review: The criteria for the diagnosis of intra-amniotic infection (IAI) were derived from a study of women at term in labor but is currently used as the main diagnostic tool for clinical chorioamnionitis. Regarding the inconsistent usage of the term, the diagnostic utility of clinical chorioamnionitis needs to be revisited. In this review, we addressed the critical issues on why the diagnostic criteria of suspected clinical chorioamnionitis should be changed.Recent findings: Overall, the accuracy of clinical chorioamnionitis to detect intra-amniotic infection (IAI) is not high, around 50%. The accuracy of each diagnostic criteria to diagnose IAI is, for example, 51.1% with maternal tachycardia, 57.8% with fetal tachycardia, and 55.6% with maternal leukocytosis. However, it needs to be reminded that these diagnostic performances had been obtained from term pregnancies but not from preterm pregnancies. Since there is a difference between clinical chorioamnionitis and histologic chorioamnionitis or even IAI, the diagnostic criteria of clinical chorioamnionitis would be ideal if it could directly predict the development of neonatal infectious outcomes. In fact, multiple definitions of clinical chorioamnionitis either in more lenient or stringent manner are currently used, which is responsible for inconsistent association of clinical chorioamnionitis with long-term neonatal outcomes. Whereas the diagnosis of clinical chorioamnionitis in preterm is followed by expeditious delivery, the diagnosis of clinical chorioamnionitis at term pregnancy is usually conducted in laboring women and requires additional neonatal evaluation for sepsis, which suggests different implications of clinical chorioamnionitis in preterm and term pregnancy.Summary: Current diagnostic criteria of clinical chorioamnionitis should be revised, specifically in terms of sensitivity in preterm pregnancy and specificity in term pregnancy.

[Management of preterm premature rupture of membranes (except for antibiotherapy): CNGOF preterm premature rupture of membranes guidelines]

OBJECTIVE

To review the different parts of therapeutic management of viable preterm premature rupture of membranes (PPROM), except the antibiotherapy and birth modalities.

METHODS

The Medline, Cochrane Library, and Google Scholar databases over a period from 1980 to September 2018 have been consulted.

RESULTS

When the diagnostic of viable PPROM is reached, the woman should be hospitalized and signs of intrauterine infection (IUI) should be sought (Professional consensus). If cervical assessment appears necessary, speculum, digital examination or cervical ultrasound may be performed (Professional consensus). It is recommended to limit cervical evaluation regardless of the method used (Professional consensus). Initial ultrasound is recommended to determine the fetal presentation, locate the placenta, estimate the fetal weight and the residual amniotic fluid volume (Professional consensus). Performing vaginal and urinary bacteriological sampling at admission is recommended before any antibiotic (Professional consensus). In the case of positive vaginal culture, an antibiogram is necessary since it can guide antibiotherapy in the case of IUI and early onset neonatal bacterial sepsis (Professional consensus). In absence of demonstrated neonatal benefit, there is insufficient evidence to recommend or to not recommend initial tocolysis in PPROM (Grade C). If tocolysis was administered, it is recommended not to prolong it for more than 48hours (Grade C). Antenatal corticosteroid administration is recommended before 34 weeks of gestation (WG) (Grade A) and magnesium sulfate administration is recommended for women at high risk of imminent preterm birth before 32 WG (Grade A). Vitamin supplementation (vitamins C and E) is not recommended (Professional consensus), and it is recommended not to impose strict bed rest in case of PPROM (Professional consensus). In case of clinical signs of IUI with cerclage, it is recommended to remove the cerclage immediately (Professional consensus). The home care management of clinically stable PPROM after 48hours of hospital observation can be considered (Professional consensus). During the monitoring of a PPROM, it is recommended to identify elements relating to the diagnosis of IUI (Professional consensus).

CONCLUSION

The level of evidence and scientific data in the literature concerning the management (except antibiotics) of PPROM are low. Initial management of viable PPROM requires hospitalization. The main objectives of the management are the detection and medical care of maternal and fetal complications.

ELABELA plasma concentrations are increased in women with late-onset preeclampsia

Objective: ELABELA is a newly discovered peptide hormone that appears to be implicated in the mechanisms leading to preeclampsia, independently of angiogenic factors. The aim of the current study was to investigate whether women with early- or late-onset preeclampsia have altered ELABELA plasma concentrations compared to gestational-age-matched normal pregnant women.Methods: This retrospective cross-sectional study focused on the maternal plasma samples collected from 232 women with a singleton pregnancy who were allocated into the following groups: (1) early-onset preeclampsia (<34 weeks of gestation, N = 56); (2) late-onset preeclampsia (≥34 weeks of gestation, N = 57); and (3) gestational-age-matched controls with a normal pregnancy [(<34 weeks of gestation, N = 59); (≥34 weeks of gestation, N = 60)]. ELABELA plasma concentrations were determined using a validated enzyme immunoassay.Results: (1) ELABELA plasma concentrations are higher in patients with late-onset preeclampsia compared with those from gestational-age-matched controls with a normal pregnancy [median: 7.99 ng/mL (IQR, 5.3-13.95 ng/mL) versus median: 4.17 ng/mL (IQR, 3-11.19 ng/mL), p =.001]; (2) ELABELA plasma concentrations in patients with early-onset preeclampsia do not differ from those of normal pregnant women [median: 6.09 ng/mL (IQR, 2.8-10.66 ng/mL) versus median: 4.02 ng/mL (IQR, 3.26-7.49), p = .32]; and (3) ELABELA plasma concentrations are higher in patients with late-onset preeclampsia compared to those with early-onset preeclampsia [median: 7.99 ng/mL (IQR, 5.3-13.95 ng/mL) versus median: 6.09 ng/mL (IQR, 2.8-10.66 ng/mL), p = .01].Conclusion: ELABELA plasma concentrations are higher in patients with late-onset preeclampsia than in those with a normal pregnancy. However, women with early-onset preeclampsia have similar ELABELA plasma concentrations to those with a normal pregnancy. These findings provide insight into the ELABELA axis during the human syndrome of preeclampsia. In addition, these data support the concept that different pathophysiologic mechanisms are implicated in early- and late-onset preeclampsia.