Psoriatic Arthritis Clinical Case Review

Ethan Craig, MD, Vice Chief of Clinical Affairs at Penn Rheumatology, reveals the selected treatment for the case.

Editor’s note: The following is an automatically generated transcript of the above video.

"Now an aspiration of the right knee, which as you can see in the prior slide, was the one that was substantially more swollen, yielded about 40 ccs of cloudy yellow fluid for which a white count of 5,700 returned with 85% poly neutrophils and positive MSU crystals were appreciated intracellular in clinic. His serum uric acid at this time was 4.9, notably his prior was 5.6 and a CRP was elevated at 1.6 mg per deciliter. Now, at this point, given failure to respond to the steroid therapy and predominant involvement of the knee, with disproportionate swelling the knee, of the right knee relative to the left, Lyme EISA and Western blot was obtained, which both returned positive. Now at this point, there's some diagnostic uncertainty.

We knew for certain that this patient did appear to have a diagnosis of psoriatic arthritis supported by the prior history of dactylitis, quite severe psoriasis and more chronic arthritis at some point. He also did very likely have a diagnosis of gout and which was confirmed on the recent aspiration of the knee with positive MSU crystals where were found intracellularly in this course of a flare and supported further obviously by the prior tophaceous deposit that was resected from his ear. In addition now, this positive Lyme titer, Lyme ELISA and Western blot was further supportive of a presumed diagnosis of late Lyme arthritis. Given the poor sensitivity of synovial fluid, Lyme PCR for diagnosis of of Lyme arthritis, and given the fact that his right knee had not responded to steroids, we opted to treat him for a late Lyme arthritis as well. And so ultimately, this patient received doxycycline for a 30 day course for this presumed Lyme arthritis, and restarted his certolizumab 400 milligrams every two weeks. And ultimately, because his uric acid was at goal at this time, he was continued on allopurinol 300 milligram daily."