What Rheumatologists Wish Their Colleagues Knew: Managing Skin Disease & Comorbidities

Many patients with rheumatic disease also suffer from skin disease, with diagnoses and treatments often overlapping or contraindicating each other. Some clinicians are more comfortable than others at treating both conditions and clearly explaining situations to their patients.

“In my opinion, rheumatologists, often, are more comfortable, or willing, to deal with all the other comorbidities of their patients’ diseases. We are much more inclined to be a primary care provider,” says Joseph F. Merola, MD, MMSc, an internist, rheumatologist, dermatologist, director of the Clinical Unit for Research Innovation and Trials (dermatology), associate program director of the Combined Medicine-Dermatology Residency Program, and co-director of the Center for Skin and Related Musculoskeletal Diseases at Brigham and Women’s Hospital in Boston.

Dr. Merola, an assistant professor at Harvard Medical School, and member of the medical board of the National Psoriasis Foundation, spoke with The Rheumatologist about how rheumatologists and dermatologists can best work together for the good of their shared patients.

Improve Screening for Inflammatory Arthritis & Psoriatic Arthritis
As many as 30% of psoriasis patients have psoriatic arthritis, and as many as 41% of patients with psoriasis have a new diagnosis of previously undiagnosed psoriatic arthritis.¹ Dr. Merola says those levels of prevalence show that both rheumatologists and dermatologists need to be educated on how to properly screen for the conditions.

“[Screening] is often tough for dermatologists, because they don’t feel comfortable doing a joint exam or asking questions about inflammatory arthritis,” he says. However, “rheumatologists will often get referrals from dermatologists for inflammatory/psoriatic arthritis in patients with osteoarthritis or fibromyalgia.”

Joseph F. Merola, MD, MMSc

Dr. Merola suggests dermatologists use a validated questionnaire, such as the Psoriatic Arthritis Screening and Evaluation (PASE), Psoriasis Epidemiology Screening Tool (PEST)  or Toronto Psoriatic Arthritis Screening (ToPAS)  survey. None is a perfect questionnaire, he says, but “all have reasonable sensitivity and specificity” for psoriatic arthritis.

“If [a dermatology] patient screens positive [using those questionnaires], they should be referred to a rheumatologist,” he says, noting early diagnosis is beneficial. “[Rheumatologists] can then get these patients to appropriate therapy more quickly, because we treat psoriatic disease with arthritis potentially differently than disease without arthritis.”

Ensure Appropriate Ordering, Interpretation of Lab Tests
Rheumatologists often get referrals based on positive antinuclear antibody (ANA) tests, many of which are false positives that trip up the referring dermatologist. These referrals for connective tissue disease or lupus often frighten patients, and Dr. Merola says rheumatologists spend “a lot of time reassuring patients” that the positive result is “not clinically meaningful.”