1/
Motivated by @TedWJamesMD to put together a #dermtwitter/#medtwitter #tweetorial for #DistanceMedEd today.
Let's do one about PAPULOSQUAMOUS DISORDERS of the skin.
What would be a good example of a papulosquamous rash you might see on #skinexam?
PC: @dermnetnz
Motivated by @TedWJamesMD to put together a #dermtwitter/#medtwitter #tweetorial for #DistanceMedEd today.
Let's do one about PAPULOSQUAMOUS DISORDERS of the skin.
What would be a good example of a papulosquamous rash you might see on #skinexam?
PC: @dermnetnz
2/
Psoriasis is the perfect example of a papulosquamous disorder. Before we break down what this means, let's start with the basics. I was taught that skin rashes & lesions fall in one of 5 reaction patterns:
- papulosquamous
- eczematous
- vesicobullous
- dermal
- red (vascular)
Psoriasis is the perfect example of a papulosquamous disorder. Before we break down what this means, let's start with the basics. I was taught that skin rashes & lesions fall in one of 5 reaction patterns:
- papulosquamous
- eczematous
- vesicobullous
- dermal
- red (vascular)
3/
By knowing which category each rash/lesion is, you can limit your Ddx.
For example:
If something is both vesicobullous and eczematous, you're probably dealing with some type of eczema.
If you're dealing with something dermal, you can probably take psoriasis off your ddx!
By knowing which category each rash/lesion is, you can limit your Ddx.
For example:
If something is both vesicobullous and eczematous, you're probably dealing with some type of eczema.
If you're dealing with something dermal, you can probably take psoriasis off your ddx!
4/
So, papulosquamous! You guessed it! It means there are papules (raised) & there is scale.
Let's break it down more:
Papules 👉 Something is infiltrating the skin causing it to be bumpy (eg: cells, foreign stuff, collagen, fluid).
Scale 👉 There is action in the EPIDERMIS.
So, papulosquamous! You guessed it! It means there are papules (raised) & there is scale.
Let's break it down more:
Papules 👉 Something is infiltrating the skin causing it to be bumpy (eg: cells, foreign stuff, collagen, fluid).
Scale 👉 There is action in the EPIDERMIS.
5/
So going back to our original ? - Why isn't it granuloma annulare (GA) or CBCL?
GA (pic1) and CBCL (pic2) are infiltrative dzs that happen in the DERMIS. Without epidermal change, there'd normally be NO SCALE.
The fact that you do see scale moves these way down on the Ddx.
So going back to our original ? - Why isn't it granuloma annulare (GA) or CBCL?
GA (pic1) and CBCL (pic2) are infiltrative dzs that happen in the DERMIS. Without epidermal change, there'd normally be NO SCALE.
The fact that you do see scale moves these way down on the Ddx.
6/
And why isn't it purpura fulminans?
Purpura fulminans is a vascular process that causes retiform purpura all over the skin from microthrombi. Think of it as DIC in the skin. It doesn't cause epidermal change at first (until it causes ulceration), and certainly not scaly!
And why isn't it purpura fulminans?
Purpura fulminans is a vascular process that causes retiform purpura all over the skin from microthrombi. Think of it as DIC in the skin. It doesn't cause epidermal change at first (until it causes ulceration), and certainly not scaly!
7/
So what does cause papulosquamous eruptions? So anything that causes infiltration of something with some epidermal alteration is going to do this! Your Ddx often includes the following:
Psoriasis
Lichen Planus
Mycosis Fungoides (CTCL)
Syphilis
Drug rashes
Tinea
... Many more!
So what does cause papulosquamous eruptions? So anything that causes infiltration of something with some epidermal alteration is going to do this! Your Ddx often includes the following:
Psoriasis
Lichen Planus
Mycosis Fungoides (CTCL)
Syphilis
Drug rashes
Tinea
... Many more!
8/
So it's a big topic, but the take away points I hope people get are:
If you see scale, think about epidermal action
If you DON'T see scale, but it's still bumpy, consider what's happening in the dermis or subcutis
Reaction patterns help you whittle down your Ddx!
So it's a big topic, but the take away points I hope people get are:
If you see scale, think about epidermal action
If you DON'T see scale, but it's still bumpy, consider what's happening in the dermis or subcutis
Reaction patterns help you whittle down your Ddx!
