Epithelioid granulomas with multinucleated giant cells are seen within the endometrial stroma, which also contains a robust lymphocytic infiltrate. A detached benign gland is seen in the upper right.
Granulomas found in the endometrium may have several etiologies. Tuberculous endometritis often comes to mind, however, other possible infectious agents include fungal infections, and parasites. For example, cytomegalovirus and the mycoplasma Ureaplasma urealyticum can also elicit a granulomatous inflammation.1,2
Other non-infectious conditions to consider include sarcoidosis and foreign-body giant cell secondary to endometrial ablation therapy. Classically, granulomas in sarcoidosis are described as being well-formed and lacking central necrosis. However, granulomas from tuberculous endometritis rarely contain central necrosis, so presence or absence of central necrosis will not be a helpful distinguishing feature. Furthermore, unless the biopsy was taken during late secretory phase, there may not be time for the granuloma to be well-formed.
Treatment will depend on etiology and the infectious agent. Note that acid-fast stains will rarely be helpful in identifying the bacilli, therefore, it is best to culture the tissue or run PCR on parafin-embedded tissue to locate an infectious organism.2
1 Robboy SJ, Anderson MC, Russell P. Pathology of the Female Reproductive Tract. London, UK: Churchill Livingstone; 2002: 293
2 Mazur MT, Kurman RJ. Diagnosis of Endometrial Biopsies and Curettings. New York, NY: Springer; 2005: PAGE. 154-5.