Uric Acid in Primary Hyperparathyroidism: Marker, Consequence, or Bystander?

Background: Several recent studies have documented an increased cardiovascular risk in patients with primary hyperparathyroidism (PHPT), thereby stimulating interest in the association with uric acid (UA), a metabolite linked to cardiovascular disease and chronic kidney disease (CKD) progression, whose role in these conditions is still the subject of study. The aim of this review is to summarize the underlying pathophysiological mechanisms of the PHPT-UA relation and discuss their potential clinical implications. Methods: We conducted a comprehensive literature review, with a focus on the physiological and clinical aspects of the relationship between PHPT and UA. Results: The evidence in the literature supports the association between PHPT and elevated UA levels, although the underlying mechanisms still need to be elucidated. Key mechanisms seem to involve tubular and intestinal transporters, particularly the ABCG2 transporter, as well as indirect effects mediated by hypercalcemia and inflammatory processes. Conclusions: The association between PHPT and UA, though recognized for years, highlights the existence of linked pathophysiological mechanisms between mineral and purine metabolism. However, the current knowledge does not clarify whether uric acid plays an active role in the development of complications related to hyperparathyroidism or if it just represents an indirect marker of metabolic dysfunction. In the absence of specific guidelines, measuring UA levels to screen for hyperuricemia, especially in patients with additional risk factors, should be considered to prevent related complications. Future studies could clarify the role of UA in PHPT, improving our understanding of the disease and potentially leading to new therapeutic strategies to prevent cardiovascular, renal and joint manifestations.