In June 2022, I listened to several presentations on gout at EULAR’s European Congress of Rheumatology. Most began with data confirming a sad truth that we, as rheumatology providers, are all aware of: too many patients are taking subtherapeutic doses of urate-lowering therapy (ULT).1,2 Recommendations from the American College of Physicians in 2017 advocated for a treat-to-symptom approach, as opposed to the ACR, which advocates a treat-to-target approach (i.e. bringing the serum urate level below 6 mg/dL). The ACP deemed the evidence for monitoring serum urate (SU) levels insufficient, leading to mixed messaging to rheumatologists and other practitioners who treat patients with gout.3
Physician understanding isn’t the only barrier to good gout care. Patients—no matter how good their intentions—may struggle to obtain the frequent labs required for ULT dose titration.
My best friend has been suffering from recurrent gout attacks for two years. He’s an educated, 37-year-old man. I referred him to an excellent rheumatologist with whom I trained. He went to the appointment and understood the game plan. He started allopurinol with flare prophylaxis months ago, but hasn’t been back to the clinic for repeat labs since. He knows he needs to go. But this father of a rambunctious 1-year-old works full time and travels frequently, and he just hasn’t found the time to return to the clinic. Hyperuricemia persists, and he continues to have gout flares.
All of this got me thinking. Why isn’t uric acid point-of-care (POC) testing a thing? Home monitoring exists for other burdensome situations, such as international normalized ratio (INR) monitoring. Wouldn’t this make sense for gout? Am I really the first person to ever think of this? In short, the answer is no. No, I’m not the first person to think about this. It exists.
History
POC testing is generally defined as a diagnostic test and analysis performed where care is provided, close to or near the patient.
POC testing isn’t new. Urinalysis is more than 6,000 years old. Although Hippocrates is credited as the first uroscopist, the Sumerians and Babylonians documented urine assessments on clay tablets as early as 4,000 B.C.4 Synovial fluid crystal analysis is distinctly younger; microscopes of sufficient magnifying power were not invented until the late 17th century.5
Antoni van Leeuwenhoek described the appearance of monosodium urate crystals from a tophus in 1679, although their chemical composition was not elucidated until many years later.6 Interestingly, he also discovered bacteria by accident. He was a cloth merchant who simply wanted to take a better look at the cloth he sold—and lo and behold, the cloth was covered in microorganisms. What’s more, he discovered human sperm. He was analyzing the ejaculate of a patient with gonorrhea and compared it to his own.5 But I digress.