April W. Armstrong, MD, MPH, of the University of Southern California, comments on the clinical manifestation of plaque psoriasis on children and adult patients, and highlights comorbidities typically associated with the condition.
Andrew F. Alexis, MD, MPH: My next question is for Dr Erin Boh. We’re going to take it down to New Orleans here. What are the clinical manifestations of plaque psoriasis? In this question, could you specifically talk about plaque psoriasis as opposed to pustular psoriasis, palmoplantar, and some of the other subtypes, Erin?
Erin E. Boh, MD, PhD, FAAD: Andy, you gave me an easy question to answer. I can do that. Psoriasis is a pretty classic disease in general. Plaque stage psoriasis has locations it likes to go to. Typically, we’ll see scalp involvement. We’ll see elbows and knees involvement, but a lot of other areas can be involved with psoriasis. They are usually red and scaly, and oftentimes they’ll be very easily bleeding. They’re itchy, but they do have a nice characteristic pattern in general. We all appreciate that nice silvery scale of psoriasis. Psoriasis can also go to intertriginous areas, so not just elbows and knees.
We’ll oftentimes see it under the axilla or in the inframammary areas. Places that are considered more severe might be genital areas. We also have locations on the nails. We see characteristic pitting of the nails with psoriasis. That’s the useful hallmark to use clinically—when people have maybe psoriatic arthritis with very minimum psoriasis. You look to the nails, and you’ll often see pitting as an associated finding. In general, we lump psoriasis into that papulosquamous scaling erythematous, thick micaceous, scaling disease that we commonly see. It doesn’t often involve the face, but we do see it sometimes in severe forms where it involves the face. It may overlap with some seborrheic areas. Of course, sometimes people will see at 2 times of presentation. You’ll see maybe early in adolescence, when it’s really younger, and maybe 15 or 20 years of age.
You might get a little bit of psoriasis starting, but then it comes back again maybe in the late 50s. It’s bimodal in its presentation very commonly. That’s useful for us because, as Andy said, some people have their familial association with it. In my practice, and many people see this, kids or adolescents with psoriasis will usually have a stronger family history. They tend to have a little more recalcitrant or hard-to-treat disease over time. Over time, psoriasis does worsen for many people.
In part, it’s because of the comorbidities that are often associated with psoriasis. Comorbidities take a little time to develop. Things like insulin resistance, hyperlipidemia, maybe atherosclerotic heart disease commonly are associated with psoriasis. Maybe you say why. It would intuitively make sense if you look at the cytokine pattern. What Andy was talking about earlier. These inflammatory cytokines are upregulated in a number of immune-mediated inflammatory diseases. Psoriasis is a very good prototype of that, but those same cytokines can cause inflammation in the blood vessels.
It can cause inflammation in the liver, in the heart, so we have to think that. Over time as these comorbidities develop and become more problematic, they can cause more of the psoriasis to flare. It contributes to that overall general systemic inflammation that we associate with psoriasis.
Andrew F. Alexis, MD, MPH: Terrific. I’m also happy that you not only did answer that so comprehensively but also touched on comorbidities. Thank you, Dr Boh.