Rob Volansky , 2025-05-07 09:30:00
DESTIN, Fla. — Challenging dermatologic conditions can take years to diagnose and almost as long to manage, according to a speaker at the Congress of Clinical Rheumatology East annual meeting.
“I tell my patients to be patient,” Katharina Shaw, MD, of the dermatology section at the Children’s Hospital of Philadelphia, and vice president of medical affairs and head of dermatology strategy at Priovant Therapeutics, told attendees.
“A lot of these skin conditions in a patient can change, make sure you are not missing something else,” Katharina Shaw, MD, told attendees. Image: Rob Volansky | Healio
Shaw presented several complicated and confusing cases of patients where the diagnosis was not immediately evident.
The first involved a patient who may have had eosinophilic fasciitis (EF) or systemic sclerosis.
“One way to distinguish EF from scleroderma is to look at the distal digits,” Shaw said. “It is important to ask about Raynaud’s.”
Specifically, she suggested asking patients to make the “prayer sign” with their hands to see if they can fully extend their fingers.
“Skin laxity is going to be preserved in EF,” Shaw said.
A pseudo-cellulite appearance may also be a hallmark of EF, as is the so-called “groover sign,” which can be marked by grooves in the skin.
“Up to 40% of EF patients will have concomitant plaque morphia, commonly seen on the abdomen,” Shaw added.
It is critical to correctly diagnose EF as opposed to scleroderma, as the treatment paradigms for the two conditions are different, according to Shaw.
“Steroids are the first-line therapy in EF,” she said. “We try to avoid steroids in scleroderma to avoid scleroderma renal crisis.”
Physical therapy to prevent joint contracture may also be necessary in EF, Shaw added.
Regardless of the intervention, Shaw counseled both doctors and patients to be patient. “Sometimes it can take years for the effect to be seen,” she said.
The next case involved a patient with an uncertain type of cutaneous lupus. She presented with signs of both systemic and discoid lupus, along with unexplained subcutaneous nodules and plaques on the upper arms and breasts. Ultimately, the exam revealed this this patient had “classic” lupus panniculitis, Shaw said.
“We have to remind ourselves what cutaneous lupus can look like,” she added. “It does not look like one disease entity.”
Cutaneous lupus can come in three “flavors,” according to Shaw.
One is acute cutaneous lupus, which is marked by the malar butterfly rash and can include generalized erythema.
Another flavor is subacute cutaneous lupus, which is often marked by a papulosquamous psoriasis form or pityriasis form.
“Significant scarring does not end up being a chronic feature,” Shaw said.
The same cannot be said for the third flavor, which is chronic cutaneous lupus.
“This is the subtype of cutaneous lupus that can cause permanent scarring,” Shaw said.
The chronic form can feature localized or generalized discoid lesions, hypertrophic discoid lupus or profundus lupus panniculitis, according to Shaw.
“This is the rarest form,” she said. “Lupus panniculitis in the breast can be confused with malignancy.”
Shaw urged physicians conducting a prolonged workup for these patients with complicated issues to remember Hickam’s dictum.
“A patient is entitled to as many diagnoses as they damn well please,” she said.
For the next case, Shaw highlighted the ways in which lupus and dermatomyositis can be confused.
“That is why they call lupus the great imitator,” she said.
Although the violaceous heliotrope rash that marks dermatomyositis is often distinct in the textbooks, Shaw suggested that it is often subtle, with midfacial erythema, in actual patients.
Rheumatologists also need to understand how the malar rash may present, she added.
“Involvement of the naso-labial folds is much more common in dermatomyositis,” Shaw said.
Gottron’s papules is another way to signify dermatomyositis.
“In dermatomyositis, they are often more scaly, ill-defined plaques that run down the end of the finger,” Shaw said.
Biopsy may not always offer a clear answer.
“Even if it says lupus at the top, it can be identical to a biopsy of dermatomyositis,” Shaw said.
Scalp involvement is another important indicator.
“Dermatomyositis likes to go to the scalp,” she said. “Scalp itch ends up being a huge quality of life issue in our patients.”
Above all, Shaw encouraged ongoing vigilance in patients with challenging skin conditions. “A lot of these skin conditions in a patient can change,” she said. “Make sure you are not missing something else.”
Sources/Disclosures
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Shaw K. Rashes and Red Herrings: Tackling Mimics in Rheum-Derm Practice. Presented at The Congress of Clinical Rheumatology East; May 1-4, 2025; Destin, Florida (hybrid meeting).
Disclosures:
Shaw reports being an employee of Priovant Therapeutics.
