Ringworm (Tinea Corporis) | Risk Factors, Symptoms, Diagnosis and Treatment

                     

Introduction

This article is on tinea corporis,  also known as "ringworm". So in this article ,  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. 

What Tinea Corporis Is?

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. 

Causative Agent:

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. 

Transmission

How is this  condition transmitted? Some of the risk factors  for transmission of tinea corporis involve direct   skin contact .

Direct 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 type of fungi in the sand   or the soil, and you were a to step on it or you  were to contact your skin with the  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. 

Indirect Contact:

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 the  and touch the that table shortly after, you could  technically pick up  a that fungi. 

Auto infection:

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. 

Risk Factors

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.

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. 

Tinea Corporis look like

So what does   tinea corporis look like? So here is tinea  corporis. As you can see,this  it is a circular  or a oval-shaped skin lesion, and it occurs on the most  body surfaces like the trunk, the arms, the neck,   the legs, except fora scalp, the hands, the  feet, and the groin. 

If a fungal infection affects  such these areas of the body  then they are of  different types  of fungal skin infections. 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 a strongly or  a clearly demarcated,  so demarcated means  the that you can clearly see the   border from the lesion to a normal skin, there  is a very distinct separation. And it is a scaling lesion. It can either be a the 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 .

Appearance:

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.  

Tinea Corporis  Gladiatorum

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. 

Cause:

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  be transmitted by the extensive direct contact with  the other   infected individuals - you can see this in  a contact  sports like football or  the wrestling. 

Occurence :

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. 

Transmitted by other individuals:

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. 

Majocchi's Granuloma 

There's also another  clinical variant of tinea corporis and that  is known as Majocchi's granuloma . 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.

Symptoms:

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. 

In which it occurs:

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 the deeper of  skin structures  .Hence causing this altered clinical  presentation. 

Clinical Diagnosis

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. 

Wet Mounting:

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. 

Treatment:

So how do we treat this condition? A lot of times we want to try to just  modify the risk factors  at first. So we talked about all those  the risk factors  before. So we want to try a to modify those, and then  we can use a 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. 

Conclusion

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.