Hey everyone! This lesson is on tinea corporis, also known as "ringworm". So in this lesson,
we're going to talk about what this condition is; we're also going to talk about what causes this
condition, and we'll also talk about some risk factors, signs and symptoms, how we can diagnose
it, and how we can treat it. So tinea corporis, "ringworm", is a superficial skin infection caused
by fungi known as dermatophytes. So, it is a fungal skin infection, and it is a relatively
common condition that occurs worldwide, and it is an infection involving the neck, the trunk,
the arms, or the legs as opposed to other areas of the body like the feet, or the groin,
which are different fungal skin infections we talk about in other lessons. Now, tinea corporis or
ringworm is actually the most common dermatophyte infection in children. So what are some of the
causative organisms? We know that they are fungi but what type of fungi? So they are dermatophytes,
like trichophyton rubrum, and trichophyton rubrum is actually the most common species
of dermatophyte fungi that causes tinea corporis or ringworm. We can also see other trichophyton
species causing this condition as well including trichophyton ... and trichophyton tonsurins and
other dermatophytes can also cause this like the microsporum species as well - we see microsporum
canis coming from cats and dogs - so cats and dogs that have microsporum canis can actually pass this
along to humans causing a tinea corporis or ringworm infection as well. How is this
condition transmitted? Some of the risk factors for transmission of tinea corporis involve direct
skin contact - so this can either be through a direct skin-to-skin contact with an affected human
or could be from an animal or it can be from the sand or soil. So if there's any fungi in the sand
or the soil, and you were to step on it or you were to contact your skin with that affected sand
or soil, you could essentially pick this fungi up and lead to an infection. And you can also
have direct skin contact with fomites. So fomites are actually indirect objects like furniture -so
if someone had tinea corporis and they were to touch a table for instance, and you came along
and touch that table shortly after, you could technically pick up that fungi. Now, there are
some other infected sites as well - you can get it from "autoinfections", so if you had a part
of your body that had another type of infection - generally speaking, the scalp (so tinea capitis)
if you have a tinea capitis infection you could spread that tinea capitis fungi to other parts of
your body. What are some of the risk factors? So some of risk factors for actually getting
tinea corporis are the following: 1) being in high humidity, in warm or hot environments; 2) wearing
tight fit clothing - so tight-fitting clothes, wearing them for a long period of time can
increase your risk for getting this condition; 3) you can also see this being common in children and
individuals who are older; and 4) we can also see it in immunosuppressed patients; 5) There is also
a genetic predisposition to fungal infections in general including tinea corporis - individuals
with decreased beta defensins or a decreased defensin beta have been shown to be more
susceptible to getting tinea infections; 6) we can also see it with individuals who have systemic
disease like diabetes and lymphoma, these are also associated with the immunosuppression - these
conditions can cause immunocompromise and increase your risk for getting tinea corporis. So what does
tinea corporis look like? So here is tinea corporis. As you can see, it is a circular
or oval-shaped skin lesion, and it occurs on most body surfaces like the trunk, the arms, the neck,
the legs, except for the scalp, the hands, the feet, and the groin. If a fungal infection affects
these areas of the body they are different types of fungal skin infections - we talk about these
in other lessons. Tinea corporis presents as erythematous and pruritic (so it's itchy) - it
has an itchy sensation to it, and as I mentioned before, it's circular or oval in shape. And you
can see here it's strongly or clearly demarcated; so demarcated means that you can clearly see the
border from the lesion to normal skin, there is a very distinct separation. And it is a
scaling lesion. It can either be a patch or a plaque, which means it can either be flat or
can be slightly raised. It spreads centrifugally, which means it spreads in all directions outward,
and as it advances, as it spreads outward with an advancing border, the center of it begins to
clear - we'll show you what an image of that looks like here in a moment. Here's another
tinea corporis - it might look like this, but it might look like this, so this is an alternate or
a variant of the clinical presentation. So this, as you can see, is very raised and the border is
sharply raised with almost papular edges to it - here's another image of tinea corporis,
and as you can see here the outer advancing border is still quite erythematous, but there's a central
clearing that's what that central clearing is. And there is also something called tinea corporis
gladiatorum. Tinea corporis gladiatorum - you can think of it as a subset of tinea
corporis - it is tinea corporis but it is tinea corporis caused in a certain way. tinea corporis
gladiatorum is often caused by trichophyton tonsurans, as opposed to trichophyton rubrum,
which is the most common cause, and it is a type of tinea corporis, because it is more often found
in athletes. And we can think of it as it's more often found in "gladiators" - that's where that
word "gladiatorum" comes from. So it's actually transmitted by extensive direct contact with other
infected individuals - you can see this in contact sports like football or wrestling. So again,
tinea corporis occurs on many different body surfaces except for the scalp, hands, feet, and
groin. It is circular or oval in shape and it is erythematous and pruritic, so it's itchy, and it
has a scaling look to it, and oftentimes is very well demarcated, spreads out centrifugalIy, and
it also oftentimes has central clearing - and then there's this odd presentation where there could be
sharp raised edges that are papular. And there's also this other term you might hear tinea corporis
gladiatorum, or what we call gladiators, that is transmitted by extensive direct contact with other
infected individuals and oftentimes it's caused by trichophyton tonsurans. There's also another
clinical variant of tinea corporis and that is known as Majocchi's granuloma sorry for the
pronunciation. So Majocchi's granuloma is actually tinea corporis that has gone a little bit wonky.
So it's actually where the dermatophyte extends down along a hair follicle, it causes somewhat of
a folliculitis that invades deeper skin structures and what we do find is that small cuts can predispose
to this condition especially shaving. It presents as papules, nodules, plaques or pustules.
So you can see a pustule here, here is another look to this condition you can see that there's
some papules here and here's another way that this condition might look. And this can actually lead to
an abscess, as the dermatophyte extends down into deeper skin structures - it can actually cause an
abscess to form. This condition is more likely to occur in males, so it is tinea corporis that
has gone a bit wonky, it has essentially extended and invaded down along a hair follicle into deeper
skin structures causing this altered clinical presentation. How do we diagnose, and how do we
treat tinea corporis? So the diagnosis of this condition involves oftentimes clinical reasoning,
or clinical diagnosis in order to definitively say that this is tinea corporis. We can do a
potassium hydroxide wet mount so a koh prep or koh wet mount - so with a koh wet mount
we look at skin scrapings from a skin lesion, and if we visualize segmented hyphae, like shown in
this image here, that is the diagnosis of a tinea infection. So how do we treat this condition? A lot
of times we want to try to modify the risk factors first. So we talked about all those risk factors
before. So we want to try to modify those, and then we can use topical antifungals so you can think
of the "-azoles". A lot of times that's the first line, but you can use naftifine and
butenafine, and we oftentimes have to use these topical antifungals once to twice a day for one to
three weeks. And important here is that nystatin is not effective for tinea corporis, and if
the topical antifungal is not effective we might have to move on to oral antifungals like in terbinafine
or itraconazole. So again, to diagnose this condition, it is often a clinical diagnosis we see
the skin lesion, and we look at risk factors and we determine that this is a tinea skin infection
or we could do a Koh wet mount and visualize segmented hyphae. Treatment involves modifying
risk factors, it's important to modify what might be causing this in the first place so it could be
tight-fitting clothing - and then we can use topical antifungal like the "-azoles", and we treat for a few
weeks and if that's not effective, we can use oral antifungals. For more information on fungal skin
infections, please check out my overview of fungal skin infections or my other lessons on athlete's
foot or jock itch for more information. If you like this video, please give it a thumbs up,
consider subscribing to the channel, and thank you so much for watching I hope to see you next time!