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Published on: July 21, 2016
Pathologist interobserver variability in diagnosing acute ascending intrauterine infection
1Forensic and Legal Medicine Unit, Department of Pathology, College of Medicine, King Saud University, Riyadh 12372, Saudi Arabia.
Abstract:
The histologic diagnosis of acute ascending intrauterine infection permits a higher-efficacy identification of both subclinical infection and clinical chorioamnionitis, but procedures for placental pathology need to adopt a unified approach and work toward reproducible grading and staging systems. We conducted a retrospective chart review of 696 placental records from single and multiple deliveries between January 2011 and February 2020. Then, we compared original diagnoses with diagnoses based on Redline criteria, which is an internationally recognized system of staging and grading. Of the 696 cases available for review, 255 had complete medical records. Findings showed a strong degree of agreement (90%-100%) between original investigators' histological diagnoses of acute ascending intrauterine infection and a review by researchers using Redline criteria. Although interobserver agreement was good, more education is needed on Redline criteria to avoid missed cases (primarily Stage 1), support protocols for pathologists and obstetricians/gynecologists in determining which cases need to be investigated, and the development of reporting standards for acute ascending intrauterine infection and feedback mechanisms during follow-up.
Insights
Histologic diagnosis of intrauterine infection is effective. Applying the Redline criteria to placental pathology showed high agreement, indicating its utility in identifying infections and guiding clinical management.
Area of Science:
- Obstetrics and Gynecology
- Pathology
- Perinatal Medicine
Background:
- Accurate histologic diagnosis of acute ascending intrauterine infection is crucial for identifying subclinical and clinical cases.
- Standardized placental pathology procedures, including reproducible grading and staging systems, are needed.
Purpose of the Study:
- To compare original histologic diagnoses of acute ascending intrauterine infection with diagnoses using the internationally recognized Redline criteria.
- To assess the agreement between original diagnoses and Redline criteria in placental pathology.
Main Methods:
- Retrospective chart review of 696 placental records from deliveries between January 2011 and February 2020.
- Comparison of original diagnoses with diagnoses based on Redline criteria for staging and grading.
- Analysis of interobserver agreement and identification of potential discrepancies.
Main Results:
- A strong agreement (90%-100%) was observed between original histologic diagnoses and the Redline criteria review.
- The Redline criteria demonstrated high efficacy in identifying acute ascending intrauterine infection.
- Interobserver agreement was good, though further education on Redline criteria is recommended.
Conclusions:
- The Redline criteria provide a reliable and reproducible method for staging and grading acute ascending intrauterine infection in placental pathology.
- Further education and standardized reporting protocols are necessary to optimize the application of Redline criteria and minimize missed diagnoses.
- Implementation of Redline criteria can support clinical decision-making for pathologists and obstetricians/gynecologists.
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