A 29 year old woman presented with dysfunctional uterine bleeding.
Specimen: A TruTest® endometrial biopsy was performed using a Tao Brush® to sample the endometrium. Ample tissue fragments were received and were separated from the endometrial sample by filtration and submitted for histology. The remaining endometrial cytology material was processed by selective cellular enhancement technique and the slides were stained with Papanicolaou and acid hematoxylin methods.
Examination of the brushing cytology slides revealed a few tubular, proliferative type glands with small amounts of attached stroma containing plasma cells and neutrophils (Fig.1, Acid Hematoxylin). Plasma cells were also identified in fragments of subepithelial stroma (Fig.2, Papanicolau stain). In the background, fibrin aggregates as well as individual plasma cells and neutrophils were found (Fig.3, Papanicolau stain). The histologic preparation revealed tubular glands embedded in a cellular stroma containing an infiltrate of plasma cells and occasional neutrophils (Fig.4 & 5, H7E stain). Mitotic figures were present in the stroma which was focally composed of spindle-shaped cells.(Fig.6, H&E stain).
When the classic features of chronic endometritis are present, the diagnosis is usually straightforward. The classic changes include a prominent plasma infiltrate with variable numbers of neutrophils, eosinophils and lymphocytes and focal breakdown. Reactive changes are present in the stroma; the stromal cells become spindle-shaped instead of round or ovoid. If breakdown is extensive, a menstrual endometrium could be part of the differential diagnosis. The reactive stromal changes and plasma cell infiltrate are absent in menstrual endometrium. Predecidualized stromal cells of later secretory endometrium have eccentric nuclei and can resemble plasma cells but they lack the peripheral clumped chromatin characteristic of plasma cells.
Chronic Endometritis, Proliferative Type Endometrium with Breakdown