One of the occupational hazards of being a Dermatologist is making diagnoses on members of the public. Sometimes I wonder if I should offer unsolicited advice on the checkout operator’s acne at the supermarket, or suggest that a complete stranger on the beach has a mole checked. Especially in the summer, another part of the skin that catches my eye is the feet.
Dermatologists get a lot of referrals about dark marks under toenails and, rightly so, since this can be a presentation of melanoma under the nail. My big toenail currently has a large black mark under it but I don’t have a melanoma. I ran the London Vitality 10k race a few weeks ago and all that pounding of the pavements of London has left me with a sub-ungual haematoma ie a bruise under the nail. It doesn’t need any treatment and I simply plan to hide it under a dark nail polish until it grows out. However, if you notice a dark mark under the nail and you can’t think of an obvious explanation for how it has appeared, it is important to have it checked out.
Causes of nail discolouration
Discolouration and thickening of the nail can also occur because of an underlying skin disease such as psoriasis. The nail can be affected by a fungal infection, which can be treated in less extensive cases with topical lacquer, or in more extensive infections with oral antifungal medication.
Another fungal infection is athlete’s foot that can usually be treated with creams or powders that can be bought over the counter. It can be more difficult to treat if you are immunosuppressed for example because of diabetes, or certain medications. In those situations, it is especially important to clear the infection so that cracks in the skin do not allow bacteria to enter and cause cellulitis.
Veruccas are warts that occur on the sole of the foot that is caused by infection with the human papilloma virus. They can be unsightly and uncomfortable and a Consultant Dermatologist can offer treatment with cryotherapy or advice about topical treatment. A solitary lesion on the foot may not be a verucca, but a skin cancer or another benign lesion, for example, a poroma and it is important to have any lesion that does not go away checked promptly.
To arrange a consultation with Dr Juliet Williams at her Surrey Dermatology Clinic to diagnose whether you’re suffering from a fungal infection or other foot problem, call 01483 555 907.