Chronic endometritis: How many plasma cells does it take to make the diagnosis?

Abstract

3–10% of endometrial biopsies are said to show histologic evidence of chronic endometritis. In this study we correlate the # of plasma cells by H&E to the # of plasma cells by CD138 IHC in endometrial biopsies.Methods100 endometrial biopsies were selected, excluding specimens with limited material, cancer and menstrual phase. H&Es were reviewed, and the # of plasma cells/10 hpfs were recorded. Additional sections were stained with CD138 antibody (clone B‐A38; Cell Marque, Rocklin, CA). Hot spots of CD138+ cells were recorded as the #/10 hpfs. Histologic findings near the CD138+ cells were also recorded.ResultsPlasma cells were identified in 29 cases by H&E alone (ave. 2.1, range 1–12) and 90 cases were + for plasma cells by CD138 (ave. 13.9 plasma cells, range 1–190). Of the 29 cases with plasma cells on H&E, CD138 highlighted an average of 24.3, with a minimum of 1. 71 biopsies lacked plasma cells on initial H&E review, but averaged 7.7 plasma cells by CD138. Often, the endometrial stroma contains scattered lymphocytes or mild edema, but lacked the spindled stroma typically associated with chronic endometritis.ConclusionsBy careful exam on H&E, >1 plasma cells were seen in 29% vs. 90% of endometrial bxs by CD138. These cases include diagnoses of gland‐stromal dyssynchrony, disordered proliferative endometria, and endometrial hyperplasias. The presence of CD138+ plasma cells may not equate to chronic endometritis.

The Diagnostic Criteria for Chronic Endometritis: A Survey of Pathologists

“…As many as 16% of cases reported as not having chronic endometritis are found to have plasma cells on second review on hemotoxylin and eosin staining (H&E) (22). Special stains uncover even higher numbers of cases where plasma cells were not identified on H&E. Immunoglobulin stains uncover an additional 30% of cases (23), while CD138 is reported to find plasma cells in as many as 69% to 90% of endometrial samples (24,25). These "missed" cases of NOS-CE in patients are apparently without negative consequence for patients (22).…”

Immune Cell Functionality during Decidualization and Potential Clinical Application

“…Elevated plasma cell (antibody-producing B lymphocytes) counts indicate chronic endometritis [ 196 ]. An altered endometrial microbiome or chronic infections can create a misregulated inflammatory environment, which impairs fertility.…”