Recognising the burden of maternal infection worldwide

Acute response to pathogens in the early human placenta at single-cell resolution

The placenta is a selective maternal-fetal barrier that provides nourishment and protection from infections. However, certain pathogens can attach to and even cross the placenta, causing pregnancy complications with potential lifelong impacts on the child's health. Here, we profiled at the single-cell level the placental responses to three pathogens associated with intrauterine complications-Plasmodium falciparum, Listeria monocytogenes, and Toxoplasma gondii. We found that upon exposure to the pathogens, all placental lineages trigger inflammatory responses that may compromise placental function. Additionally, we characterized the responses of fetal macrophages known as Hofbauer cells (HBCs) to each pathogen and propose that they are the probable niche for T. gondii. Finally, we revealed how P. falciparum adapts to the placental microenvironment by modulating protein export into the host erythrocyte and nutrient uptake pathways. Altogether, we have defined the cellular networks and signaling pathways mediating acute placental inflammatory responses that could contribute to pregnancy complications.

Association of white blood cell count after operative vaginal delivery with maternal adverse outcome: A retrospective cohort study

BACKGROUND

The white blood cell count is often used to assess the maternal condition after an operative vaginal delivery. However, it remains unknown whether the maternal white blood cell count on the day after delivery is associated with sequential maternal adverse outcomes, especially infectious complications. The aim of this study was to investigate the association between maternal white blood cell count on the day after operative vaginal delivery and sequential maternal adverse events.

METHODS

The study was a retrospective cohort study using the Medical Data Vision claims database containing administrative claims data, discharge abstracts, and laboratory values in Japan. We identified all patients who underwent operative vaginal delivery with data on maternal white blood cell count from December 2011 to November 2020. The main composite outcome was maternal adverse outcomes, comprising additional treatment for maternal injuries, postpartum intravenous antibiotic use, and intensive care unit use during hospitalization. We conducted a restricted cubic spline analysis to investigate the nonlinear association between white blood cell count and the primary outcome.

RESULTS

There were 485 eligible patients including 73 patients with occurrence of the primary outcome. The median (interquartile range) white blood cell count on the day after delivery in all eligible women was 15,170 (12,610-18,300)/mL. In the restricted cubic spline analysis, there was no significant association of white blood cell count with the primary outcome.

CONCLUSION

White blood cell count on the day after operative vaginal delivery was not significantly associated with maternal adverse outcomes during hospitalization.

A systematic review of biomarkers associated with maternal infection in pregnant and postpartum women

BACKGROUND

Serum biomarkers are commonly used to support the diagnosis of infection in non-pregnant patients whose clinical presentation suggests infection. The utility of serum biomarkers for infection in pregnant and postpartum women is uncertain.

SEARCH STRATEGY

PubMed, CINAHL, EMBASE, ClinicalTrials.gov, Cochrane Library, CINAHL, and SCOPUS were searched from inception to February 2020.

SELECTION CRITERIA

Full-text manuscripts in English were included if they reported the measurement of maternal serum biomarkers-and included a control group-to identify infection in pregnant and postpartum women.

DATA COLLECTION AND ANALYSIS

two authors independently screened manuscripts, extracted data, and assessed methodologic quality.

MAIN RESULTS

Interleukin-6 (IL-6), C-reactive protein, procalcitonin, insulin-like growth factor binding protein 1, tumor necrosis factor-α, calgranulin B, neopterin, and interferon-γ inducible protein 10 reliably indicated infection. Intercellular adhesion molecule 1, monocyte chemotactic and activating factor, soluble IL-6 receptor, and IL-8 were not useful markers in pregnant and postpartum women.

CONCLUSIONS

Findings suggest that certain biomarkers have diagnostic value when maternal infection is suspected, but also confirms limitations in this population.