52-year-old female, chronic pain of finger, hand and shoulder joint. Now pain and swelling of knee. Arthroscopy and biopsy.
- Plump, villous tela synvovialis, covered by multiple layers of covering cells(possibly fibrin)
- The stroma contains lymphocytic and plasma cell infiltrates with development of lymphoid follicles.
- Occasional lesions of the covering cell layer can be due to granulocytic infiltrates.
Comment: A pathological finding is suggestive for chronic polyarthritis but not pathognomonic. History, clinical findings and serology are essential.