Skin biopsy

What is a skin biopsy?

A skin biopsy is a short procedure used to take a small piece of skin. This is then sent to the laboratory. Here, they can look at it under a microscope, or grow more cells from it.

Why does my child need a skin biopsy?

We take a skin biopsy to help us confirm or rule out a diagnosis. The reason for this skin biopsy will be explained to you by your doctor.

Written consent

Before your child has their skin biopsy, the doctor will give you a full explanation of what it will involve. You will then have the chance to ask any questions that you might have. You will then be asked to sign a written consent form. This gives your doctor permission to do the biopsy.

How is the skin biopsy taken?

A skin biopsy is usually taken while your child is awake, but sometimes they will be given a medicine to help them feel relaxed and sleepy. This is known as sedation.

A cream is rubbed onto the area of skin where the biopsy is going to be taken. This will make the skin numb, so that it does not hurt when the skin is taken. After about 45 minutes, the cream is wiped away. Your child might need a little bit of anaesthetic injected in the skin to make it fully numb.

When the skin is numb, a small circle of skin is removed. This circle is 3mm wide or less, and is taken using a tool called a punch biopsy. This is gently inserted into your child’s skin, carefully turned, and a small circle of skin is taken.

When the skin has been taken, the small wound will be closed. This is done using either a couple of steri-strips, which are thin strips of plaster, or with a couple of stitches.

After the skin biopsy

Steri-strips

If the wound has been closed with steri-strips, the advice is to:

• keep them dry
• leave them in place for 10 days
• after 10 days, soak them in warm water and gently peel them off

Stitches

If the wound has been closed with stitches, you are advised to:

• keep them dry for 2 days
• arrange an appointment with your specialist nurse or GP practice to have the stitches removed

Results

After the skin biopsy has been sent to the laboratory, it can take a few weeks before they have results of the tests. An appointment will be made in clinic to give you these results.

Complications

Every procedure that cuts into the skin has a risk of minor complications. This is also true for skin biopsies.

Bleeding

There is a small risk of bleeding during the biopsy, and straight after the procedure. This is usually very minor, and is stopped by pressing onto the area with gauze.

Discomfort

There will likely be some soreness around the place where the skin was taken. This will not last for very long, and some paracetamol (or Calpol) should help with the pain. Use this as the directions on the bottle or packet say.

Infection

There is a small risk of infection after a skin biopsy. If the biopsy site does become infected, a short course of antibiotics might be needed. You can spot an infection by looking out for redness, pain, swelling, and oozing (liquid, pus, or goo) coming out of the wound.

If you are worried about an infection, be sure to get in touch with your doctor or GP as soon as you can.