ZocdocAnswersWhat exactly is ringworm?

Question

What exactly is ringworm?

I?m a boxer so I?m in the gym a lot. My coach says I might have ringworm. I have a small circle on my arm, but it has gotten bigger. I am a guy and I am 23 years old. Is there something I should do about this?

Answer

Sorry to hear that you may have ringworm. The term ringworm is actually a misnomer as it isn't actually caused by a parasitic worm at all, but rather a fungus. The medical term for ringworm is "dermatophytosis", and while there are many different species of fungi that can cause it, most commonly it is due to two different fungi classes called Trichophytum and Microsporum. It sounds like you may have something called tinea corporis which means that the fungal infection is involving the trunk, arms, or legs. It it was affecting your scalp it would be called tinea capitus. Nonetheless the fungus lives and feeds on the outer layer of your skin called the epidermis. As it grows and expands it appears like an elevated red concentrically enlarging circle. Some describe it as a "halo" that gets continually larger. Thus the active fungus is typically found at the lateral (red) margins of the circle. This is why if you go to a doctor and they decide to perform a scraping (where they scrape some of the skin and look for fungus under a microscope), it will be done from the periphery. I would recommend going to your primary care physician to be checked out, because there are anther few disease processes that can present with a "halo" lesion on the skin. If it is in fact "ringworm", then they will be able to recommend and prescribe the appropriate anti-fungals. I hope that this is helpful. Best of luck.

This answer is for general informational purposes only and is not a substitute for professional medical advice.

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