, clinical assistant professor in the department of dermatology at the University of Texas Southwestern Medical Center, Dallas, spoke at the Pigmentary Disorders Exchange Symposium, provided by MedscapeLive!
Like all dermatologists, he said at the meeting, he sees lots of acne cases. However, PIH is often the presenting reason for the visit in his practice, which focuses predominantly on skin of color.
“Most of my patients come in not even worried about the acne,” he said. “They come in wanting me to fix the dark spots.”
Dermatologists, Dr. Desai said, should educate patients with active PIH resulting from acne or other diseases that even though the condition has been labeled post- inflammatory hyperpigmentation, the inflammation continues to be a problem.
He said, while patients may think PIH is “just scars,” the inflammation is still active and the condition needs to be treated from a skin-lightening perspective but, more importantly, with a focus on halting the inflammation. “If you were to biopsy the areas of hyperpigmentation, you would find a high density of active inflammatory behaviors still present in the skin,” he said.
When treating patients, it’s critical to first treat the underlying skin condition aggressively, he said. “Things like topical retinoids and azelaic acid mechanistically actually make a lot more sense for PIH than even hydroquinone, in some cases, because these therapies are actually anti-inflammatory for many of the diseases we treat.”
Dr. Desai noted that, in patients with darker skin tones, even diseases like seborrheic dermatitis and plaque psoriasis can result in PIH, while in patients with lighter skin tones, the same diseases may leave some residual postinflammatory erythema.
“I think it’s very important, particularly when you’re treating a darker skin–toned patient, to arrest the erythema early on to prevent that further worsening of hyperpigmentation,” he said.
In cases of PIH, determining the best treatment requires finding out where the pigment is and how deep it is, Dr. Desai said.
He noted dermatologists are often worried about doing biopsies, particularly in patients with darker skin, because of the risk of scarring and keloid formation for those more prone to keloids. The preference is also for a therapeutic effect without using invasive procedures.
“But particularly with PIH, in patients who have been therapeutically challenging, I don’t hesitate to do very small biopsies – 2- and 3-mm punch biopsies – particularly if they are from the head and neck area.”
He suggests doing biopsies on part of the ear, lower jaw line, or the neck area, as these areas tend to heal nicely. “You don’t have to be so concerned about the scarring if you counsel appropriately,” he said.
The biopsy can be valuable in determining whether a very expensive treatment will reach the intended target.
Topical retinoids play an important role as anti-inflammatories for PIH, Dr. Desai said.
He gave an example of a patient with Fitzpatrick skin type IV or V with chronic acne and extensive PIH. “Are you going to effectively tell that patient to apply 4% hydroquinone triple-combination compound across 30 different areas of PIH on their face? The answer is that’s really not very efficient or effective.”
That’s why therapies, such as retinoids, that target the pathogenesis of PIH, particularly the inflammatory component, are important, he added.