Tinea corporis ("Ringworm")


Tinea corporis more commonly known as “ringworm” is a superficial fungal infection of the skin.  It can occur anywhere on the body including the palms, soles, hair, nails and groin area. When it is on the body is called tinea corporis, when it is on the groin area it's called tinea cruris, and when it's on the feet it’s called tinea pedis. But despite the different names it's all the same infection.


Common questions I get from patients include the following. "How did I get it? Is it contagious? Will it go away? Tinea corporis can result from human to human, animal to human, or soil to human spread. Can it spread to other parts of your body? Indeed it can, and often times someone may spread the infection from their feet after intense scratching and spread it to their groin or other parts of their body. Contracting the infection may occur from occupational or recreational exposure such as those in military housing, from locker rooms, gymnasiums and from close contact sports like wrestling, boxing, and mixed martial arts. With the gaining popularity of mixed martial arts (MMA), more and more young people with these infections have been presenting to my dermatology clinic.  

Generally the infection spreads from the center outwards, thus creating a circular rash often times with central clearing


The lesions are typically very itchy and scaley. Often times these lesions look similar to eczema and are inappropriately treated with topical corticosteroids such as hydrocortisone creams by either the patient or the primary care doctor. Cortisone creams actually work against you, by suppressing the local inflammatory response, which is needed to clear the infection. It’s like taking away the breaks on a moving car. A very simple in-office examination of scrapings of the skin by a specialist physician like a dermatologist can confirm a diagnosis of tinea corporis. The scrapings are put on a microscope slide and KOH is applied which helps dissolve away the keratin, allowing better visualization of the fungi. 
                 

Most cases of tinea corporis are easily managed with topical antifungal creams prescribed by the physician. In complicated cases (those that have been treated aggressively with cortisone creams) or more severe infections, oral antifungal medications are needed to eradicate the infection.

Majocchi granuloma is a deep folliculitis due to a dermatophyte (fungal) infection. It is most commonly due to Trichophyton rubrum infection. This type of fungal infection most commonly occurs as a result of the use of strong topical steroids on unsuspected tinea infection (ringworm). In other words, a patch of “ringworm” or tinea gets misdiagnosed as eczema and a high potency topical steroid is prescribed. The corticosteroid takes away the local immune response to the fungus, allowing it to penetrate deeper into the follicles instead of remaining on the local skin surface. Oral antifungals are usually necessary because topical agents alone are not effective. (pic below in elderly patient)


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