Join me for a #dermtwitter #tweetorial on:


#MedEd #FOAMEd #medstudenttwitter #MedTwitter

Let's start ourselves off with a question: Which one of the following conditions will lead to scarring?
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!
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)!
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).

PC: @Medscape
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).
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!
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...
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.
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.
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.
✅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!
Hope this helps! Thanks for joining, and see you next time on another #dermtwitter #tweetorial/#medthread!

And Happy Thanksgiving!

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More from @DrStevenTChen

7 Nov
Hi #dermtwitter/#medtwitter! Our last (for now!) #tweetorial/#medthread on nails! This time it’s...


Education from @naildisorders and the @jmervak team!

@societypedsderm @PeDRAResearch #medstudenttwitter #medtwitter #meded #FOAMed
Beau’s lines (transverse ridge) and onychomadesis (nail shedding) common in kids! Often seen in a post-viral setting.

Common culprit = hand foot mouth disease!
Congenital malalignment of the great toenails – lateral deviation of the first toenails. More common than you think. Start looking at more toes and you’ll see it! Can improve with time or persist. Risk for nail thickening or ingrown nails.

pc: sciencedirect.com/science/articl…
Read 12 tweets
27 Oct
Join me for a quick #tweetorial/#medthread on:

Pearls for the #Dermatology Exam!

#MedEd #dermtwitter #medtwitter #medstudenttwitter #FOAMed

First a question - What do you think when someone asks for your help with a rash?
Regardless how you answered, I hope to teach you something today! Let's start!

"In #dermatology, we don't do an H+P, we do a P+H."

The exam is perhaps most important. You can use it to narrow down your ddx! Then, you use your history to further work toward the right dx.
"If there's scale, there probably is epidermal involvement."

Scale usually implies action in the epidermis. This doesn't rule out anything in the dermis or subcutis, but just that the pathology includes action up top.

Check out my #tweetorial on scale
Read 10 tweets
24 Oct
Hi #dermtwitter! Back for another #tweetorial/#medthread on nails! Today we’re learning about:

ONYCHOMYCOSIS- nail fungus!
This is THE most common nail condition- so follow along!
Education from @naildisorders
#medstudenttwitter #medtwitter #meded #FOAMed
Onychomycosis is more common in adults than kids.
Trauma, diabetes, immunosuppression, tinea pedis, psoriasis, and family history are some risk factors

Pro tip- check the feet for tinea pedis if you suspect onychomycosis!

Patients with onychomycosis present with nail discoloration (yellow to brown), onycholysis (nail separation), nail brittleness, or nail thickening.

The big toenail is most frequently affected.

Fingernail involvement without also have toenail involvement is uncommon.
Read 14 tweets
3 Oct
Hi #dermtwitter! I'm working with @jmervak et al, who put together this amazing #tweetorial on


Specifically, findings in the setting of systemic diseases: let nails help your diagnosis!

Coordinated with @naildisorders

#medstudenttwitter #medtwitter #meded #FOAMed
First things first, do you mind telling us who you are?
3/Let's begin: Beau’s lines! Transverse depression across the nail. Means the nail briefly stopped growing and started again.

Seen weeks after nail injury! Or, if it's seen on multiple nails, ask about febrile illness (like post #covid19) or stressors like SJS or chemotherapy.
Read 16 tweets
6 Feb
Let's spend some time on a #dermtwitter #tweetorial on all things....


Even though there are 8 herpesviruses that infect humans, I'm going to focus on HSV1 and HSV2 today.

#medtwitter #medstudenttwitter #meded #FOAMEd
You know how we say that everything could be sarcoid? Well, HSV-1/HSV-2 (which I'll refer to as herpes for this #thread) would be a close 2nd, ESPECIALLY on the inpatient service.

While HSV-1 is usually thought to be oral and HSV-2 genital, this certainly is NOT always true.
The class exam finding for herpes is the "dew drop on a rose petal." In clinical speak, that would be a vesicle on an erythematous base. But often we don't see the vesicle intact.

For ex, the photo above shows intact vesicles, whereas here, we just see the resultant crust.
Read 16 tweets
2 Jan
Let's kick off the new year with a #dermatology #tweetorial! I put together some tweets on


#MedEd #FOAMEd #medtwitter #dermtwitter #onctwitter

Let's start with a poll:

Among BOTH males and females in the US, how common is melanoma?
Melanoma is the 6th most common malignancy (that's tracked) for BOTH men & women. Basal cell carcinoma is actually the MOST common cancer in the US, but we don't track it.

While melanomas are 6th, in certain groups (eg: women age 25-30), it is the #1 cause of cancer death! Image
So melanoma is deadly, especially in certain age groups. But something peculiar is happening too. @AdeAdamson recently spoke at @MassGeneralNews about this interesting finding 👉 melanoma diagnosis is increasing, but melanoma death is decreasing.

Read 18 tweets

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