Perinatal pathology: practice suggestions for limited-resource settings

Survey Data and Experience from a Pediatric Pathology Workshop in Indonesia: Understanding Practice Needs and Utility of Outreach Teachings

Objective: We aimed to share the post-workshop survey results of a pediatric pathology course held in Jakarta, Indonesia. Methods: Questionnaires were distributed to participants; responses from practicing pathologists and pathologists-in-training were analyzed. Results: The respondents (107 pathologists of 143 attendees) were predominantly female (83.2%) and 31-60 years of age (77.5%). Over half (71.7%) signed out pediatric and perinatal specimens but only a third (34.3%) were comfortable handling such cases. Most (70.0%) felt that their exposure to pediatric and perinatal cases during their training was inadequate. All respondents thought that the workshop was helpful, and would highly recommend it to their colleagues. Post-workshop, the respondents claimed expansion of differential diagnoses (49.5%) and better understanding of what to include in pathology reports (41.1%). Conclusions: Our experience affirms the need for subspecialty courses to address training gaps in developing countries. Post-workshop surveys are helpful in determining actionable deficiencies and effectiveness of outreach teachings.

Mapping cell-to-tissue graphs across human placenta histology whole slide images using deep learning with HAPPY

Accurate placenta pathology assessment is essential for managing maternal and newborn health, but the placenta's heterogeneity and temporal variability pose challenges for histology analysis. To address this issue, we developed the 'Histology Analysis Pipeline.PY' (HAPPY), a deep learning hierarchical method for quantifying the variability of cells and micro-anatomical tissue structures across placenta histology whole slide images. HAPPY differs from patch-based features or segmentation approaches by following an interpretable biological hierarchy, representing cells and cellular communities within tissues at a single-cell resolution across whole slide images. We present a set of quantitative metrics from healthy term placentas as a baseline for future assessments of placenta health and we show how these metrics deviate in placentas with clinically significant placental infarction. HAPPY's cell and tissue predictions closely replicate those from independent clinical experts and placental biology literature.

Building Perinatal Pathology Research Capacity in Sub-Saharan Africa

Introduction

Over two million stillbirths and neonatal deaths occur in sub-Saharan Africa (sSA) annually. Despite multilateral efforts, reducing perinatal mortality has been slow. Although targeted pathologic investigation can often determine the cause of perinatal death, in resource-limited settings, stillbirths, early neonatal deaths, and placentas are rarely examined pathologically. However, the placenta is a key source of diagnostic information and is the main determinant of fetal growth and development in utero, influencing child health outcomes.

Methods

In 2016, our collaborative intercontinental group began investigating infectious perinatal death and adverse child health outcomes in Uganda. We developed and initiated a 4-day combined didactic/practical curriculum to train health workers in placental collection, gross placental examination, and tissue sampling for histology. We also trained a local technician to perform immunohistochemistry staining.

Results

Overall, we trained 12 health workers who performed gross placental assessment for > 1,000 placentas, obtaining > 5,000 formalin-fixed tissue samples for research diagnostic use. Median placental weights ranged from 425 to 456 g, and 33.3% of placentas were < 10th percentile in weight, corrected for gestational age. Acute chorioamnionitis (32.3%) and maternal vascular malperfusion (25.4%) were common diagnoses.

Discussion

Through a targeted training program, we built capacity at a university-affiliated hospital in sSA to independently perform placental collection, gross pathologic examination, and placental tissue processing for histology and special stains. Our training model can be applied to other collaborative research endeavors in diverse resource-limited settings to improve research and clinical capacity and competency for diagnostics and management of stillbirth, neonatal death, and child health outcomes.

Placental Pathology Associated with Household Air Pollution in a Cohort of Pregnant Women from Dar es Salaam, Tanzania

BACKGROUND

Smoke from the burning of biomass fuels has been linked with adverse pregnancy outcomes such as low birth weight, stillbirth, and prematurity.

OBJECTIVE

To identify potential underlying mechanisms of adverse perinatal outcomes, we explored the association of placental pathology with household air pollution in pregnant women from urban/periurban Tanzania who cook predominantly with charcoal.

METHODS

Between 2011 and 2013, we measured personal exposures to fine particulate matter (PM2.5) and carbon monoxide (CO) over 72 hr among a cohort of Tanzanian pregnant women. Placentas were collected after delivery for examination. Placental pathologies of inflammatory, hypoxic, ischemic/hypertensive, infectious and thrombotic etiologies were diagnosed, blinded to exposure levels. Using multiple logistic regression, we explored the association of PM2.5 and CO exposure with placental pathology.

RESULTS

One hundred sixteen women had personal air exposure measurements and placental histopathology available for analysis. PM2.5 and CO exposures were moderate [geometric means (GSD) were 40.5 μg/m3 (17.3) and 2.21 ppm (1.47) respectively]; 88.6% of PM2.5 measurements exceeded World Health Organization air quality guidelines. We observed an increase in the odds (per 1-unit increase in exposure on the ln-scale) of fetal thrombotic vasculopathy (FTV) both with increasing PM2.5 [adjusted odds ratio (aOR) = 5.5; 95% CI: 1.1, 26.8] and CO measurements (aOR = 2.5; 95% CI: 1.0, 6.4) in adjusted models only. FTV also was more common among pregnancies complicated by stillbirth or low birth weight.

CONCLUSIONS

Fetal thrombosis may contribute to the adverse outcomes associated with household air pollution from cook stoves during pregnancy. Larger studies are necessary for confirmation. Citation: Wylie BJ, Matechi E, Kishashu Y, Fawzi W, Premji Z, Coull BA, Hauser R, Ezzati M, Roberts D. 2017. Placental pathology associated with household air pollution in a cohort of pregnant women from Dar es Salaam, Tanzania. Environ Health Perspect 125:134-140; http://dx.doi.org/10.1289/EHP256.