Diagnosis
Metaplastic squamous epithelium
Pseudoactinomycotic radiate granules (PAMRAGs)
Discussion
Pseudoactinomycotic radiate granules (PAMGRAGs) are amorphous eosinophilic collections of glycoproteins, lipids, and calcium, and are non-infectious. They are theorized to be a response to foreign bodies, including IUDs. While primarily described in the female genital tract, they may also be seen in the head and neck. On histology, they appear as refractile eosinophilic granules, with broad peripheral radiations. This appearance is reminiscent of the granules of Actinomyces, which is the primary differential diagnosis. Actinomyces are an anaerobic gram-positive filamentous bacterium which is associated with foreign bodies, particularly long-term IUDs. While they may exist indolently as part of the flora of the gynecologic tract, they are pathogenic and can rarely cause pelvic inflammatory disease and abscess formation. On histology, they appear as basophilic granules with a dense eosinophilic core. The periphery has thin, filamentous branching. To distinguish it from PAMRAGs, special stains for GMS, PAS, and Gram stains may be performed. The Actinomyces organisms will be highlighted in all three stains, while the PAMRAGs will not.
Due to the clinical implications, it is imperative for the pathologist to be able to distinguish the two entities. Importantly, the presence of PAMRAGs does not preclude the presence of Actinomyces. Careful examination on microscopic sections as well as the use of ancillary studies is imperative to achieve a diagnosis.
References
- Pritt B, Mount SL, Cooper K, Blaszyk H. Pseudoactinomycotic radiate granules of the gynaecological tract: review of a diagnostic pitfall. J Clin Pathol. 2006;59(1):17-20. doi:10.1136/jcp.2005.028977
- Nwanguma, Adaugo, and Kshitij Arora. “Pseudoactinomycotic Radiate Granules in the Gynecological Tract: A Case Report.” Cureus vol. 16,9 e69062. 10 Sep. 2024, doi:10.7759/cureus.69062