Chlamydia trachomatis in the endometrium: can surgical pathologists identify plasma cells?

Chlamydia trachomatis infection is the most common bacterial sexually transmitted disease. The authors examined the relation between chronic endometritis, which they term plasma cell endometritis (PCE), and chlamydial infection using plasmid-based polymerase chain reaction (PCR) and immunohistochemical staining (IHC) of paraffin-embedded endometrial sections. C. trachomatis infection was detected in 5 (24%) of 21 cases of PCE and in 1 (4%) of histologically normal endometrium. The diagnosis of chronic endometritis (with plasma cells confirmed by methyl green pyronin staining) was correctly made in 74% of the cases originally diagnosed as PCE and in 23% of control cases originally diagnosed as normal. The authors conclude that the histopathologic finding of plasma cells in endometrial samples should encourage further examination for chlamydial infection.