Researching morphea: UV-A1 phototherapy recommended for darker-skinned patients

October 1, 2009

World report - Darker-skinned patients with morphea and related diseases are as likely to benefit from ultraviolet (UV) light therapy as patients with lighter skin. Some clinicians had speculated that the increased level of melanin found in darker skin might impede UV-A1, but that does not appear to be the case.

World report - Darker-skinned patients with morphea and related diseases are as likely to benefit from ultraviolet (UV) light therapy as patients with lighter skin. Some clinicians had speculated that the increased level of melanin found in darker skin might impede UV-A1, but that does not appear to be the case.

Heidi Jacobe, M.D., assistant professor of dermatology at the Southwestern Medical School, in Dallas, undertook the study because most evaluations of UVA therapy are conducted in Europe with fair-skinned Fitzpatrick type I and II patients.Furthermore, the speculation of muted response to therapy did not seem to correlate with what she was seeing in the clinic.


The study

Dr. Jacobe conducted retrospective analysis of 101 patients receiving UV-A1 phototherapy at the University of Texas Southwestern Medical Center, which appeared in the June edition of the British Journal of Dermatology.

"Among patients with types III and IV, they seem to do very well. The take-home point is that even if you have patients with darker skin types, they are amenable to treatment with UV-A1, and that option should be considered," Dr. Jacobe says.

Broadband UVA light sources generate rays in the 320 nm to 400 nm range, while UV-A1 are longer waves in the 340 nm to 400 nm range, she says.

"Research tends to show that UV-A1 does have some differing biological effects on the skin than either the lower wave length UVA and UVB.

"UV-A1, unlike other types of phototherapy, very rarely burns people, so we usually treat patients with the same regimen, regardless of skin type. If they are extremely fair, we might reduce the dose a bit at first. The major exception is if they are on some type of medication that makes them photosensitive.

"What we’ve seen across the board is that patient response tends to plateau around 40 treatments, regardless of their skin type," Dr. Jacobe says.

She suggests the possibility of some synergy resulting from simultaneous use of UV-A1 with other therapies.

"The combination of methotrexate and UV-A1 seems to work well, but I can’t say anything definitely based on the data we have," Dr. Jacobe says.

The numbers of patients so far is too small to power such subgroup analysis.


Early treatment

"The earlier and more inflammatory the disease, the better the response to treatment; very inactive, burned-out lesions don’t tend to respond at all," she says. "If you treat the disease during the inflammatory stage, you can get a very good response. Jumping on it early is very beneficial for patients."

Unfortunately, patient awareness of the rare disease is virtually nonexistent, and clinicians seldom are much better. Dr. Jacobe says most patients think they just have a bruise, and when they do finally go to a physician, the problem is not identified.

"Oftentimes, they see several physicians until they finally end up with a dermatologist, who might make the right diagnosis. There is a lot of confusion with scleroderma," she says.

"“There is a problem of education on multiple levels. The textbooks tend to show advanced stage disease and very sclerotic lesions, so no one thinks of it early on where it can be not sclerotic at all, but very erythemic-looking,” Dr. Jacobe says.

While the histology of morphea and scleroderma is identical, the later has a very definitive onset and progression beginning with the fingers, while morphea often begins as a plaque elsewhere on the skin.

"“You should think of morphea when you see erythema with some thickness to the dermis underlying it,” Dr. Jacobe says.


Preliminary data

"Preliminary data suggests that certain patients with morphea tend to have other autoimmune disorders, as well as a small increased familial risk, very much like what has been seen with scleroderma," she says.

Dr. Jacobe believes all of this points toward "a common autoimmune susceptibility gene, similar to the polygenic disorder of vetiligo, with certain environmental triggers that we have yet to identify."

She is very aggressive in identifying the disease early. She says that her study was "enriched" with patients who were identified and started on therapy early in their disease. Patients who are no longer in the inflammatory phase of active disease are rarely started on therapy. This is likely to skew the rates of response.


Study weakness

Khalil Khatri, M.D., a dermatologist in private practice in the Boston area, says it was a good and useful study, but perhaps the title of the paper was a bit misleading.

"Only 22 of the patients had darker skin categorized as types IV to V, while most patients were types I to III," and there were no patients with the darkest skin, type VI.

Furthermore, "the comparison is not equal, because they don’t all have the same kinds of skin conditions" and they were allowed to simultaneously use other therapies, he says.

Still, given the difficulty of identifying large numbers of patients with this rare condition, he found it "useful data," given the paucity of literature on the disease. It answers the primary question that UVA treatment is safe in this patient population, and appears to be similarly efficacious.

In Dr. Khatri’s opinion, the morphea registry that Dr. Jacobe is creating will be a useful tool in gaining a better understanding of this rare, variable condition and response to therapies. DT