Doctors with nerve.

Physician FAQ

Many doctors and clinics approach CRL for small fiber neuropathy (SFN) and epidermal nerve fiber density (ENFD) testing. At CRL, we partner with providers who wish to diagnose patients who may suffer from small fiber neuropathy. The following answers to the most frequently asked questions will help providers understand our small fiber neuropathy testing services. If you have any other questions on how our testing can assist you with a diagnosis, please call us at 855-CRL-LABS (855-275-5227).

Why Choose CRL to perform the Epidermal Nerve Fiber Density (ENFD) test?

We are grateful that you have chosen Corinthian Reference Laboratory (CRL) to perform the epidermal nerve fiber density (ENFD) testing as a diagnostic tool for small fiber neuropathy. There are many benefits to choosing CRL to perform ENFD testing. CRL is the only lab exclusively specializing in ENFD testing that also provides all of the following:

  • Biopsy kits that can be stored up to one year without expiring.
  • No cumbersome freezer packs.
  • Kits are contained in flat packaging requiring minimal storage.
  • Dedicated sales team for personalized service.
  • Downloadable color reports.
  • Samples read by both a neurologist and dermatopathologist.
  • Access to our clinical support team including dedicated nurse specialists, neurologist and dermatopathologists.
  • Easy shipping process- you will never have to wash or freeze a sample
I would like to start doing skin biopsies in my office. How do I begin?

You may either sign up online at the CRL homepage or call our lab at 855-CRL-LABS to speak to one of our customer service representatives. We will deliver kits within two business days of your request. The kits take up minimal space and may be stored flat for up to one year. We will also ensure a dedicated sales representative is assigned to your group for personalized service.

What does each kit contain?
Each kit will contain three vials of fixative, three fixative labels, a 3 mm Dermapunch kit, four CRL Referral Forms, and a FedEx Large Clinical Pack to return the samples to CRL.

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I've received my kits in the mail, what next?
If you are familiar with the skin biopsy procedure, you may use the kit we send to complete the procedure. Please review the CRL skin biopsy procedure overview for important procedure tips. If you are not familiar with the procedure, please review the skin biopsy video to view the procedure in its entirety. You may also call one of our qualified nurse specialists at 855-CRL-LABS for additional procedure information. You will also want to review the CRL Referral Forms before beginning.
I've completed the skin biopsy, how do I send it to CRL?
Please place the appropriately labeled fixative vials containing the samples into the biohazard bag and then place that bag in the black CRL envelope provided. You will also include the completed CRL Requisition Form and patient information in the CRL black envelope with the vials. Then place the black CRL envelope in the FedEx Large Clinical Pack. Call FedEx at 1-800-463-3339. Biopsies may be taken Monday-Friday and MUST BE SENT THE SAME DAY AS THE PROCEDURE.
I have biopsied multiple patients on the same day. Can I send the samples to CRL at the same time?
You may wait until the last biopsy of the day to call FedEx for pickup. If you performed a biopsy on Tuesday afternoon and have one scheduled for Wednesday morning, you must send the samples taken on Tuesday by the end of the day Tuesday and the samples taken Wednesday by the end of the day Wednesday. After each biopsy, place appropriately labeled fixative vials containing the samples, patient information and CRL Requisition Form in the black CRL envelope provided. While you may combine multiple black CRL envelopes into one FedEx Large Clinical Pack, you may only include the information and samples from one patient into each black CRL envelope.
I was using another pathology lab and still have some of their kits. Can I use these kits when sending samples to CRL?
The kits sent by CRL are specifically designed to accommodate our unique processing. Samples sent to CRL for processing must be contained within the CRL fixative and include the CRL Requisition form and appropriate patient information. The fixative used by CRL is unique in that the samples do not need refrigeration and you do not need to store or send cumbersome freezer packs. There is also no need for any manipulation of the samples once placed in the fixative vials. We designed the referral process to be as simple and streamlined as possible and our referring physicians appreciate our process.
Who do I call if I have questions regarding the report?
Each biopsy is processed and read by both a neurologist and a dermatopathologist. You may call one of our physicians to review the results. If you have questions about the skin biopsy procedure, you may contact one of our qualified nurse specialists. Our clinical team can be reached by calling 855-CRL-LABS.
How do I order additional kits?
There are several ways you may order additional kits. You may order by phone by calling CRL at 855-CRL-LABS or call or e-mail your personal sales representative. You can also go to the CRL website and click on the “Order Test Kits” button on our homepage.
How do I bill for the skin biopsy?
The CRL Billing Form contained within the referral forms sent by CRL will provide you with the necessary billing codes for your office to bill the skin biopsy procedure. This form also contains the most common diagnostic codes as well as an opportunity to document the patient name, date of birth and procedure date for your billing records. If you need additional assistance please contact our team of reimbursement specialists at 855-CRL-LABS.

Skin Biopsy Procedure

CRL Small Fiber Neuropathy Algorithm Video