Psoriasis (PsO) and psoriatic arthritis (PsA) often travel together, which is why dermatologists and rheumatologists need to collaborate and ensure that patients receive the best and most appropriate care for their skin and joints.

Around one in three people with PsO also have PsA, according to the National Psoriasis Foundation, and the link is bidirectional.

“Some patients have skin disease and develop arthritis, but lots of patients have arthritis first and then the psoriasis presents months or years later,” says Olga Petryna, MD, an attending rheumatologist at Scarsdale Medical Group/White Plains Hospital in New York.

“It’s important that rheumatologists look out for skin manifestations in PsA patients and dermatologists ask about arthritis symptoms in people with psoriasis,” Dr. Petryna tells DermWire.

Ask psoriasis patients if they are experiencing chronic joint pain that doesn’t get better with over-the-counter pain relievers, stiffness in the morning, or swelling of digits. “This can help identify early manifestations of PsA, even if undiagnosed, and then you can refer the patient to a rheumatologist for a thorough evaluation.”

Collaboration doesn’t stop with two-way referrals, she said. Dermatologists and rheumatologists also need to work together to make sure patients receive the best treatment for all of their symptoms.

“Some of the treatments may work better for musculoskeletal symptoms and others work better for skin, and it’s always a concern that if you treat one domain, you undertreat the other and don’t fully control inflammatory disease,” she says. 

For example, some of the medications like methotrexate failed to show efficacy in axial disease, while some show better response on combined skin and joint scores compared to the others in head-to-head trials, she explains.

“When I diagnose arthritis in a psoriasis patient, assess its severity, and determine how much treatment the patient requires, I will reach out to the dermatologist about the severity of skin disease so we can correctly choose a biologic or non-biologic disease-modifying antirheumatic drug," she says.

Communication and collaboration between specialists has improved. “It’s getting better, but we still have a ways to go,” she says

Joint rheumatology and dermatology clinics are one way to make sure patients have access to both types of specialists “These exist in some academic centers and could be a huge benefit if it is feasible,” she says.  In 2017, there were more than 20 such clinics in The US, and this number has likely increased since then, according to research in Current Rheumatology Reports1.

Organizations such as the Rheumatologic Dermatology Society: RDS provide physicians with evidence-based research and effective techniques for treating or managing patients with cutaneous manifestations of rheumatologic diseases.

Patients with inflammatory diseases like PsO and PsA are at higher risk for cardiovascular disease and diabetes, so other specialists are also needed to coordinate care, she adds.

1. Soleymani T, Reddy SM, Cohen JM, Neimann AL. Early Recognition and Treatment Heralds Optimal Outcomes: the Benefits of Combined Rheumatology-Dermatology Clinics and Integrative Care of Psoriasis and Psoriatic Arthritis Patients. Curr Rheumatol Rep. 2017 Nov 20;20(1):1. doi: 10.1007/s11926-017-0706-0. PMID: 29185062.