We are aware of the clinical importance of diagnosing psoriatic arthritis (PsA) as early as possible to initiate appropriate therapy. Because psoriasis precedes PsA in the majority of cases, it is incumbent on clinicians to seek any evidence of joint involvement at each clinical encounter.
In a study published online on February 25 in Annals of the Rheumatic Diseases. Faustini et al reported that patients with psoriasis but without PsA experience structural joint changes at the entheses. Therefore, evidence for structural joint alterations may already exist at the time of apparently exclusive skin involvement in psoriatic disease.
In the analysis, 85 participants without arthritis, including 55 with psoriasis and 30 healthy controls, received high-field magnetic resonance imaging (MRI) of the hand. These scans were scored for synovitis, osteitis, tenosynovitis, and periarticular inflammation. Participants with psoriasis also received complete clinical investigation as well as high-resolution peripheral quantitative computed tomography for detecting erosions and enthesiophytes. All participants were followed for at least 1 year to evaluate for the development of PsA.
Magnetic resonance imaging evaluation showed that 47% (26/55) of participants with psoriasis possessed at least 1 inflammatory lesion. Synovitis was the most prevalent inflammatory lesion (38% [21/55]), while osteitis (11% [6/55]), tenosynovitis (4% [2/55]), and periarticular inflammation (4% [2/55]) were less frequent.
The incidence of enthesiophytes and bone erosions did not differ between patients with psoriasis, with or without inflammatory changes on MRI. The risk for developing PsA was as high as 60% in those with subclinical synovitis and symptoms related to arthralgia. However, the risk was only 13% if the patients had normal MRIs and did not report arthralgia. Faustini et al concluded that the prevalence of subclinical inflammatory lesions is high in patients with cutaneous psoriasis. Specifically, arthralgia in conjunction with MRI synovitis constitutes a high-risk constellation for the development of PsA.
What’s the issue?
These findings are critical, as they indicate the nature of the potential genesis of PsA in many patients. If the data are confirmed in future investigations, it may change the way we evaluate or treat early PsA. How will these findings affect your workup for early PsA?