A multidimensional algorithm could help clinicians diagnose gout in primary care and urgent care settings, according to a review published in the Annals of Internal Medicine.
Sydne J. Newberry, PhD, from the RAND Corporation, and colleagues, examined the accuracy of clinical tests and classification algorithms compared with a reference standard of monosodium urate (MSU) crystals in joint aspirate for diagnosing gout. The review was conducted to support an American College of Physicians (ACP) clinical practice guideline.
The researchers used data from electronic databases, including PubMed, EMBASE, the Cochrane Library, and the Web of Science, through February 29, 2016. They analyzed 21 studies that included participants with joint inflammation and no previous definitive gout diagnosis who had an MSU analysis of joint aspirate.
The data showed that recent algorithms that included clinical, laboratory, and imaging criteria demonstrated good sensitivity up to 88% and fair to good specificity up to 96% for diagnosing gout, with moderate strength of evidence. In 3 studies that examined dual-energy computed tomography (DECT), the researchers found sensitivities of 85% to 100% and specificities of 83% to 92% for diagnosing gout.
In addition, 6 studies that examined ultrasonography showed sensitivities of 37% to 100% and specificities of 68% to 97%. Results were dependent on the ultrasonography signs assessed (pooled sensitivity and specificity for the double contour sign: 74% and 88%, respectively).
“The results of studies assessing the sensitivity and specificity of various clinical algorithms for gout diagnosis or classification suggest that these instruments show promise for providing at least a provisional gout diagnosis in patients who present with signs of early-stage disease, who are most likely to be seen in primary, urgent, and emergency care settings,” the authors wrote.
“Imaging methods, such as ultrasonography and DECT, also seem favorable for gout diagnosis, but primary and urgent care settings may lack access to such equipment or the expertise necessary to use these techniques.”
- Newberry SJ, Fitzgerald JD, Motala A, et al. Diagnosis of gout: A systematic review in support of an American College of Physicians clinical practice guideline. Ann Intern Med. 2016. doi: 10.7326/M16-0462.