Drs Rosmarin, King, and Pandya give an overview of clinical presentation and classification of vitiligo.
Brett King, MD, PhD: David, we’re going to turn to you. Can you discuss the clinical presentation and the classification of vitiligo? Building on that, discuss some of the key distinctive features and anatomic regions that may be affected. Amit alluded to this earlier, that when vitiligo presents in typical areas, he has less concern about something else being at the root of this. Lead us through this part of the discussion, please.
David Rosmarin, MD: There are different ways we can categorize and classify vitiligo, but most commonly we classify vitiligo into segmental, nonsegmental, and mixed. The most common form of vitiligo is nonsegmental. It’s ironic that we’re defining the most common form of the disease by what it’s not, which is nonsegmental. Most of the time, when we use the term vitiligo, we’re referring to that type, nonsegmental. In the nonsegmental type, there are different versions. It’s often symmetric on the body. Very commonly, it can affect the face, the hands, armpits, and genital region, but anywhere on the body can be affected. One thing that’s been noted, though, is that it commonly affects areas that are a little more darkly skin-toned: the face, the dorsal hands, the axillae, the genitals often have a darker natural color to the skin. Those are the more frequent areas affected by vitiligo.
The other form, which is less common, is segmental. That affects a portion of the body. Often it’s referred to as affecting a dermatome, either on the head and neck or the trunk. Those are the most common areas. It’s usually a single dermatomal region, although there are rare cases where it can affect more. The segmental form behaves differently because usually it rapidly depigments in that area, and then it stops and stabilizes. That’s not always what happens in the more common nonsegmental form of vitiligo, where patients can continue to have progressive disease throughout their life. It can be stable for years, and then they get lesions. But the segmental form rapidly depigments and then stabilizes.
The third type is mixed, a combination of segmental and nonsegmental. It’s certainly the least common of all forms. If patients have segmental vitiligo, but also have halo nevi, that might be a slight predictor that they may move on to the mixed phenotype. In general, vitiligo can affect anywhere on the body, but the most common anatomical locations are those that are more darkly colored. Face is the most common location, followed by the hands, axillae, genitals, and wrist, but anywhere in the body can be affected. It can affect less than 1% to almost the entire pigment network on the body being destroyed.
Brett King, MD, PhD: There’s 1 vexing thing that patients often want to know, and of course we’d love to know the answer to this. If I have a little on my fingers or on my face, what’s going to happen next? Does involvement of any site predict further involvement, or is it never totally clear what’s going to happen next?
David Rosmarin, MD: Unfortunately, we can never be certain about what will happen, but some clinical clues are very helpful that tell us if the vitiligo will be stable or more progressive. For example, there are 4 main indications on physical exam that tell us that the vitiligo may be progressive. The most common type is if the patients have trichrome or 3-colored vitiligo—they have the normal skin tone, the deep pigmented area, and a third color that’s between those 2. The second type, which we know of thanks to the work of Amit Pandya, is the confetti vitiligo: small 1- to 2-mL hypopigmented macules that may be splattered on the body. That indicates that the vitiligo is active. The last 2 types are much less common. One is if we see the Koebner phenomenon, which is when a patient has a scratch that has induced vitiligo, or if they have inflammatory vitiligo, which is when they have a red ring around their disease. Those can indicate that the vitiligo is progressive and something that it requires intervention to stop the progression of disease and stabilize it as a first step before we think about the second step of repigmentation.
Brett King, MD, PhD: As a final question as an add-on to this, what proportion of patients have limited body surface area involvement vs more extensive? I’m sure that we could have a separate discussion about the meaning of limited vs more extensive. But is there a way to say that there’s a 70% chance that this is all you’re going to have vs a 30% chance that you’re going to progress to more widespread disease. How do you think about that?
David Rosmarin, MD: The majority of patients have limited disease. Most patients have 5% of their body or less affected by vitiligo. When I say a body surface area of about 1 palm on the patient—not our palm but the patient’s palm—that’s 1% of their body surface area. Usually, I’ll use those clinical signs to guide patients to whether there may be more at risk for progressing. Certainly, if they have segmental vitiligo, counsel them that it’s unlikely that they will progress further beyond what they’ve already have.
Amit Pandya, MD: Can I make a comment on that?
Brett King, MD, PhD: Please.
Amit Pandya, MD: First, I want to reiterate what David said about active signs of activity. This is super important. We did a study looking at 200 new patients coming to our clinic. We found that 61% had confetti, trichrome, or Koebner phenomenon lesions, or 2 or more of those. Even if you have 3% of your body involved or less of vitiligo, if you have those signs, this isn’t a patient who should be treated with local therapy. They’re in danger of expanding their vitiligo, and they should be treated with full-body phototherapy, at least for a while, to stop next week’s lesion and next month’s lesion.
The other thing is that in the CHA2DS2-VASc Score, we use the entire hand for 1%. As David said, most patients with vitiligo have less than 5%. I think 3% to 4% is the mean body surface area for vitiligo. This may seem small, but when you’re talking about the face and the hands, that’s huge. The entire face is 3.5%. If you have 3% to 4% body surface area and your face and hands are involved, this can be a significant psychological distress to the patient.
Brett King, MD, PhD: Amit, thank you for bringing up those points. It’s important what both of you said about these signs of active disease because, as we’re going to get to, treating this disease isn’t that easy. To the extent that we have a clue in time that somebody is progressing, for sure treating less disease is going to be easier than treating more disease. It’s critically important that we look for these signs of active disease so we can do everything that we can to keep the patient from coming back in 6 months or a year with twice as much or 3 times as much disease to treat.
Transcript Edited for Clarity