Hello,

Thanks for posting your query.

I understand that you are a vigilant and health conscious individual and appreciate the same.

You did the right thing by visiting the urgent care, they have checked the lesion with woods lamp (blue light) because fungal infection most commonly causes ring shaped lesions.

The other likely causes can be an allergic rash, a bacterial infection or a bruise itself due to minor trauma to the fine blood vessels below the skin, or rarely vitamin c deficiency causing easy bruise without trauma or a chronic inflammatory skin disorder.

Now to differentiate between these a thorough clinical examination, a detailed history and if necessary some blood tests might be needed like complete blood counts, thyroid profiles, coagulation profiles etc.

In your case it seems to me most likely to be either a minor bruise or an infection and nothing worrisome as such. Anyways the diagnosis wil be much clear once your lab reports are available.
If its just a bruise it wil gradually change colour to bluish XXXXXXX if infection it may spread or increasein size without typical colour change.

So don't worry it may resolve after treatment.

Do not apply any chemical or cream unless advised by your doctor, you may apply a topical anti inflammatory antibiotic cream if your doctor has advised.

Hope I have answered your query.

I'll be available for any follow up queries.

Regards

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