Efficacy of FNA vs Traditional Biopsy for Confirming Tophaceous Gout

Fine-needle aspiration (FNA) cytology may be an effective alternative to traditional biopsy methods for diagnosing gout, according to research published in the Journal of the American Society of Cytopathology.

Researchers from the Wexner Medical Center at Ohio State University in Columbus, Ohio, conducted a retrospective review of 22 patients with FNA cases of tophaceous gout.

A total of 18 men and 4 women were included in the review (mean age 55 [range, 33-78] years). Within the patient population, 7 participants had a clinical history of gout and 5 were taking gout medication.

In all 22 patients, researchers identified soft tissue masses in either upper (n=5) or lower (n = 17) extremities, with size ranges between 1.5 cm and 10 cm.

Researchers reported that in all patients, material collected via FNA showed “white paste-like precipitate.” In addition, extracellular polarizing needle-shaped crystals with negative birefringence were present and were visible on both stained and unstained smears. Whereas necrosis was largely absent, some material indicated the presence of multinucleated giant cells, histiocytes, lymphocytes, and neutrophils. For all patients, researchers were able to confirm the initial FNA diagnosis.

The researchers noted that this review was, to their knowledge, the largest review of FNA biopsy cytopathology of gouty tophi; 15 previously published reports were single-case reports.

“FNA biopsy has proven to be a valuable tool in the evaluation of soft-tissue mass lesions, and is a practical alternative to synovial/soft tissue core needle or open biopsy for crystal demonstration given the fact that it is a less invasive, rapid, simple, and cost-effective technique, and just as reliable diagnostically,” the researchers concluded.

Reference

Li Z, Jin M, Wakely PE Jr. Aspiration cytopathology of tophaceous gout: a report of 22 patients. J Am Soc Cytopathol. 2018;7(3):149-153.