番茄社区

What caused this middle-age woman's chronic, asymptomatic psoriasis-like facial rash? And why has it persisted for 10 years, despite trials with a myriad of therapies?

This baffling case led to a search for a diagnosis and an effective treatment, said Noah Goldfarb, MD, of the University of Minnesota Medical School in Minneapolis, and colleagues in .

The patient, in her early 40s, presented to the clinic with discoid, pink-orange, flat-topped papules and plaques with light scale scattered across her face and neck. She told clinicians that she developed the rash 10 years previously, and during that time, it had not responded to a range of 16 different treatments. She explained that while it was not itchy or painful, it was taking a toll on her quality of life.

On physical examination, clinicians noted multiple orangish-pink papules and plaques with clear boundaries on her forehead, cheeks, jawline, and neck; the lesions were flat-topped and covered with fine scale. The rash did not extend to her ears, torso, arms, or legs.

Laboratory test results showed no markers of antinuclear antibodies or multiple lupus erythematosus. Patch testing did not elicit any significant reactions. The team biopsied a specimen from a facial plaque, which revealed hyperkeratosis with focal parakeratosis, mild irregular psoriasiform hyperplasia, follicular hyperkeratosis, and a mild superficial perivascular lymphocytic infiltrate; notably, there were no characteristics typical of interface dermatitis.

Based on clinical and pathology findings, clinicians diagnosed the patient with facial discoid dermatosis (FDD).

The patient's medical history from the past several years revealed attempts to treat the rash with a wide variety of therapies. Topical medications included numerous corticosteroids of various potency, including calcipotriol, topical tacrolimus, permethrin cream, tazarotene 0.1% cream, topical metronidazole, and ketoconazole cream and shampoo. Numerous systemic therapies had also been tried, including prednisone, low-dose oral isotretinoin, methotrexate, metronidazole, hydroxychloroquine, doxycycline, minocycline, oral fluconazole, and excimer laser. All therapies had produced very little improvement, or none at all.

The authors' literature review identified a few recent reports of cases of pityriasis rubra pilaris (PRP) that had shown significant clinical response to treatment with ustekinumab (Stelara). Based on the hypothesis that FDD and PRP may be associated conditions, they proposed a trial of ustekinumab. The patient received 45-mg injections of the biologic on day 0 and day 28, and every 12 weeks thereafter.

After 6 weeks of treatment, the patient's facial redness and scaling showed considerable improvement. On physical examination, clinicians noted a significant reduction in inflammatory activity, so that only faint pink patches with slight desquamative scale were evident on the cheeks, neck, and jawline. The patient noted that as her rash had improved in appearance, texture, and flaking, her quality of life had also improved substantially. Furthermore, she reported having no serious adverse effects.

Discussion

Goldfarb and colleagues noted that given the paucity of information on FDD and lack of any consistent benefits reported with any treatment, "increased awareness of FDD and further studies of ustekinumab therapy for this rare dermatosis may allow for earlier recognition and intervention to reverse the cosmetically disfiguring appearance."

This typically chronic facial dermatosis -- the cause of which remains undetermined -- was first described only 12 years ago, in 2010, the group pointed out. Characterized by persistent, disk-shaped plaques with minimal scale that are stable over years, FDD is notably "refractory to numerous topical and systemic treatments, including corticosteroids, topical calcineurin inhibitors, antibiotics, immunomodulators, and phototherapy."

FDD appears to be in women, with a male-to-female ratio of 1:5.5, tends to develop when patients are in their 30s, and most commonly among Asians.

The morphologic characteristics of FDD are similar to those seen in patients with psoriasis, discoid lupus erythematosus, seborrheic dermatitis, and PRP, and histology findings include "hyperkeratosis, parakeratosis, and psoriasiform acanthosis, often with follicular plugging and a perivascular lymphocytic infiltrate," Goldfarb and team wrote.

In the process of arriving at the diagnosis of FDD, clinicians encountered reports suggesting that FDD may be associated with PRP. Specifically, "some authors have postulated that FDD may be a variant or forme fruste of PRP," Goldfarb and team wrote. The two are rare skin conditions, both characterized by an orange-pink color and dry scale, with comparable histology, and often show a similar resistance to treatment.

Additionally, they noted a in which a patient with FDD was later diagnosed with type 2 PRP.

They recommended this patient's trial of ustekinumab suggesting that it is an effective treatment for typical forms of PRP.

The authors said that the rapid clearance observed in this patient within 6 weeks of starting ustekinumab, accompanied by a significant improvement in quality of life, "suggests that it could be a promising treatment option for FDD and supports the notion that FDD may be associated with PRP."

Comment