Transcript
Announcer:
Welcome to DermConsult on ReachMD. On this episode, we’ll hear from Dr. Matthew Zirwas, an American Board of Dermatology certified physician and the Founder of Bexley Dermatology Research in Ohio. He’ll be discussing challenges in diagnosing eczematous dermatitis, which he spoke about at the 2026 Maui Derm NP and PA meeting. Here’s Dr. Zirwas now.
Dr. Zirwas:
The idea of the most difficult eczematous conditions to diagnose is fascinating. I would say it's much easier to say the easy ones to diagnose because the vast majority of chronic dermatitis is difficult to diagnose. We're moving, as a field, away from the idea that we should be using the terms “dermatitis unspecified,” “dermatitis NOS,” and things like that.
Really we should be trying to categorize dermatitis into allergic contact dermatitis, irritant contact dermatitis, or atopic dermatitis.
A minority of cases are obvious. So they've had it since they were a child, it's flexural, they've got asthma or allergies, and it's obvious classic atopic dermatitis. Easy. Second, it's an obvious contact dermatitis. When they wear cheap earrings, their earlobes break out. Whenever they wear rubber gloves, their hands break out. It's obvious allergic contact dermatitis. And then there's cases where it's obvious irritant contact dermatitis. They wash their hands 30 times a day and they have a rash on their hands. That's obvious irritant contact dermatitis. That is the vast minority of cases.
The gigantic majority of cases are cases where they've got eczema on their face, scattered on their body, on their hands, or on their shins. There's no obvious contact allergen. You take a history, and there's no obvious contact irritant. They didn't have as a child. It’s not flexural. So there's no obvious one of the big three that it is. What do I do now?
And the problem is there's no test. A biopsy doesn't help. I hate to say this, but patch testing doesn't really help because the vast majority of positive patch tests, even the ones that we call relevant in the situations that I'm talking about, are not relevant. The patient avoids them and they don't get better. It ends up being that treatment becomes what's going to lead to diagnosis. So you try and treat them with something that is not a non-specific drug. If you treat them with a topical steroid, that's potentially going to get all of these better. So you try and you treat them. “Okay, try getting away from this, try getting away from that. Make this change, do that, try this medication.” And it ends up being that we can only really definitively diagnose most cases of eczematous dermatitis based on how they respond. And even with a lot of experience, it often comes down to a best guess and then seeing how they respond to treatment.
Announcer:
That was Dr. Matthew Zirwas discussing challenges in eczematous dermatitis diagnosis. To access this and other episodes in our series, visit DermConsult on ReachMD.com, where you can Be Part of the Knowledge. Thanks for listening!
