Let's start ourselves off with a question: Which one of the following conditions will lead to scarring?
2/ The correct answer is Pyoderma Gangrenosum! This illustrates a quick first point - scarring only occurs if you damage the skin into dermis and beyond. Epidermal damage heals without scarring, which is why the first 3 don't lead to scarring!
3/ So what exactly is a scar?
Scarring is a normal part of healing that at its root, is extra collagen laid down to repair skin injury.
However, sometimes the process gets out of hand and exuberant which leads to hypertrophic scars (pic 1) keloids (pic 2)!
4/ So what's the difference between hypertrophic scars & keloids? Both have excess collagen & both can be itchy, inflamed, and bothersome.
Hypertrophic scars tend to be limited to areas of trauma, but importantly, they tend to resolve over time (months to years).
5/ Keloids, on the other hand, tend to be larger and can continue to spread to adjacent tissues with active borders.
Histologically, keloids and hypertrophic scars have ⬆️ cellularity, vascularity, & connective tissue, but keloids have thick collagen fibers (think bubblegum).
6/ So how do you treat them?
The mainstay of therapy for both is usually intralesional steroids. Patients often have to come back repeatedly for injections.
The best at home treatment I know of is silicone scar sheets. In fact, we used these ourselves for our daughter!
7/ What if the simple stuff doesn't work?
Sometimes it's a matter of getting the actual steroid into the skin/scar. In those cases, special instruments can be tried, such as this dermajet. It literally just shoots the medication into the scar without a needle - just air...
8/ And in tough cases, we'll also inject 5-fluorouracil into the scar (usually mixed with the steroids).
The 5-FU has been shown to downregulate fibroblasts, leading to decreased collagen production.
9/ And there are a variety of surgical/physical techniques. These include laser and surgical excision.
The problem of course is any damage to the skin can more scarring, so these are often paired with medical treatment at the time of the procedure.
10/ People with darker skin unfortunately develop keloids and hypertrophic scars more. I don't know of any research to show why that is.
Ultimately, it's important to take a history of prior keloids/hypertrophic scars before operating on any patient.
pc:medicalnewstoday.com/articles/keloi…
11/ RECAP:
✅Scars, hypertrophic scars, & keloids are from ⬆️ collagen.
✅Keloids keep spreading, Hypertrophic scars usually stay put in areas of trauma.
✅ Lots of medical treatments available. OTC would consider silicone gel sheets!
✅ Take a keloid history before operating!
Hi #medtwitter and #dermtwitter! Since I'm giving a talk at the upcoming @SocietyHospMed Converge meeting, I thought I'd put together a brief #tweetorial on:
DIFFERENTIATING PEMPHIGUS AND PEMPHIGOID!
Follow along for a reminder on how to tell them apart! 1/
Reminder that Pemphigus is from an antibody targeting the Desmosome - which holds skin cells (keratinocytes) together.
Pemphigoid is from an antibody targeting the Hemidesmosome, which holds keratinocytes to the basement membrane.
pc: 2/ bookdown.org/jcog196013/BS2…
So to remember:
pemphiguS (S for Superficial/higher up)
pemphigoiD (D for Deep/lower down)
This also means the clinical exam is different. Since Pemphigoid is deeper, these bullae stand tall and proud and don't droop over (see pic)! We call these TENSE bullae. 3/
If everyone could just humor me for a little, here's a #dermtwitter/#medtwitter/#pharmtwitter #tweetorial on...
AZATHIOPRINE
Did you know that dermatologists use this medication too? Read on to see all the ins and outs of safety and dosing, from a #dermatology point of view! 1/
Did you notice those two rings above? That's how it works.
Azathioprine is a purine (see figure) analogue, so it gets in the way of RNA/DNA synthesis (making transcription and replication and all that downstream goodness more difficult). 2/
And as you might imagine, cells that are rapidly dividing (like your immune cells) would be affected more by this purine disruption.
But it's not azathioprine itself that does all the work. It has to be broken down into active metabolites and that's where it gets interesting. 3/
The spirochete Borrelia burgdorferi is the most common cause. It is transmitted via tick bite, and so, certain areas of the country have higher rates based on endemicity of the organism.
What tick classically transmits lyme?
2/
Ixodes tick is the classic vector for B burgdorferi. But remember:
The tick usually has to be attached to the patient for >36 hours to transmit and cause Lyme disease.
Can you identify all these types of ticks and pick out which one is Ixodes?
We're seeing more consult questions for this, and it's also garnering national attention, so let's take a brief moment in #tweetorial format to talk about:
What is Xylazine? It was created in the 70s as a veterinary anesthetic. As an analog of clonidine, it has similar effects as an alpha-2 agonist, leading to sedation, anesthesia, and euphoria in the CNS. 2/
Recently, Xylazine has entered the drug supply, moreso in certain cities, but increasingly everywhere. It is often mixed with fentanyl as a cutting agent, and can also be used on its own. It may be called Tranq, Zombie Drug, or anestesia de caballo (horse anesthetic).
3/
Let's go back to the basics. Syphilis is from an infection by the bacterium Treponema pallidum. Usually spread by sexual means, syphilis has three main stages of disease.
Primary infection usually presents as a papule that turns into a painless ulcer called a chancre. 2/
Time from inoculation to chancre usually is 10-90 days (21 days is most typical).
There is a rare variant where the patient can get many smaller ulcerations, which is called Follman balanitis. 3/
Let’s spend some time in this #tweetorial on the dermatologic manifestations of this potentially paraneoplastic disease!
First, a question: What is necessary to make a diagnosis of DM?
1/
None of the above! DM is a clinical diagnosis, which is why getting the exam right is super important! That said a biopsy CAN help with getting to a diagnosis, but it’s not necessary.
So let’s start! Heliotrope rash! This poikilodermatous erythema occurs around the eyes. 2/
Remember though that exams are different across skin tone. Heliotrope can look a lot more subtle in someone with more melanated skin. That rash can also include the rest of the face! 3/