Gout is now the most common form of inflammatory arthritis in the United States, with a recent resurgence of research interest in its cause and management. Calcium crystal–related arthritis has also attracted renewed attention, with new nomenclature having been recently elaborated, aiding contemporary research efforts. Novel insights regarding risk factors for gout and calcium crystal–related arthritis, including dietary, lifestyle, and genetic factors, have been elucidated in the past decade, providing new management options and treatment targets for drug development. Patients with crystal-related arthropathies are also recognized to have higher prevalence of certain comorbidities that themselves require specific management efforts.
With improved understanding of the biologic basis for the acute inflammatory response in acute gout, new pharmacologic agents for the management of acute gout are being developed and tested, providing additional therapeutic options for patients suffering from gout. New treatments for hyperuricemia have also been developed, including some that are directed at pathways not previously targeted by the traditionally used urate-lowering therapies. One of the major consequences of inadequately managed hyperuricemia is the occurrence of tophi. It is now better understood that tophi are not inert deposits of urate, but rather are biologically active and contribute to joint destruction, affecting the integrity of both bone and cartilage. Calcium crystal deposition is also increasingly being recognized as a potential etiologic factor contributing to the onset and progression of joint damage, including osteoarthritis. Advances in imaging technology are providing new insights into the nature and extent of both calcium and urate crystal deposition and will enable greater insights into their effects on joint damage. Such imaging modalities may also offer new avenues for testing the efficacy of new pharmacologic agents in crystal-related arthropathies, complementing the biochemical and patient-reported outcomes used presently. In summary, there have been tremendous advances in understanding the epidemiology, biology, imaging, structural consequences, and management of crystal-related arthropathies, but much work remains to be done.
The articles in this issue provide in-depth reviews of the current state of these scientific advances and lay out a framework for a research agenda that will eventually advance the care of millions of patients with crystal-related arthropathies worldwide.