Do you treat patients for Small Fiber Neuropathy? Do you perform EMGs and Nerve Conduction Studies on these patients without conclusive results? Would you like a definitive answer before you proceed with your patient’s treatment process? Epidermal Nerve Fiber Density (ENFD) testing with Ipsum Diagnostics can provide you with the crucial clinical diagnosis you need in order to appropriately treat your patients with SFN.
Small Fiber Neuropathy is often an undiagnosed disease, and the only way to DEFINITIVELY diagnose it is by taking a skin biopsy and performing ENFD testing. Diagnosis can be extremely helpful in determining which treatment option is best for a particular patient. Early detection can also be important since detection of reduced small nerve fiber density can predict the progression to a larger-spread neuropathy. An ENFD test can reduce overall healthcare costs, unnecessary surgeries, unnecessary treatments and improve patient care. Once diagnosed and treated, ENFD testing can be utilized to evaluate that course of treatment for patient improvement, and can be adjusted accordingly if necessary. Standard tests for nerve damage such as electromyograms and nerve conduction studies (EMG and NCS) are gross measures of large nerves, but they cannot give the appropriate information on the health of small sensory nerve fibers.
These are the four most commonly tested sites: Calf, Thigh, Wrist, and Upper Arm. The actual sites and the number of locations is a personal clinical preference. However, the recommended maximum number of biopsies on a single patient is four. A provider will often take a distal and proximal biopsy from a limb or limbs experiencing neuropathic symptoms. Obtaining a biopsy from a distal and proximal site will help determine if the neuropathy is length-dependent.
The decision to perform bi-lateral biopsies is also a personal clinical decision. Dr. Stephen Barrett, the past president of the Association of Extremity Nerve Surgeons, and an expert in the field of Peripheral Neuropathy has the following thoughts on performing Bi-Lateral biopsies for ENFD testing.
"It is absolutely necessary to do a bilateral ENFD for a patient with peripheral neuropathy in order to differentiate true metabolic axonopathy versus a sequela of entrapment that may or may not be superimposed on the metabolic disease. It is possible that a patient may have a subclinical peripheral nerve entrapment unilaterally, and by taking a biopsy from only the most symptomatic extremity, this does not help to establish a complete and accurate diagnosis for the patient. Is there a contribution of any underlying metabolic component? That can only be established by testing both extremities. For example, we encounter many type II diabetics who have burning pain bilaterally, but when get the ENFD results, one side is demonstrably worse than the other. Can this be solely attributed to distal symmetrical polyneuropathy resulting from the metabolic impairment? No—most likely not, unless there is a significant vascular difference which would have been noted on clinical exam. Why would this be? Most of the time it is due to the fact that the patient has a severe nerve entrapment, which was insidious in onset by the very nature of the disease, in addition to the metabolic component, that is contributing to their small fiber loss. The hyperglycemia is symmetrical—the nerve fiber density is not? It is my opinion that not performing a bilateral ENFD in a patient with peripheral neuropathy is below the standard of care.”
For a comprehensive assessment, additional stains can be performed on the same specimens being utilized for the ENFD testing.
-Congo-Red-Determines if an amyloid is detected.
-H&E-Can show evidence of Vasculitis.
Performing a Punch Biopsy in your office
In order to obtain a specimen that can be evaluated by Ipsum Diagnostics, a simple 3mm punch biopsy must be taken by a physician or mid-level provider at your practice. This simple procedure is performed under local anesthetic (typically about 1CC of 2% lidocaine with Epinepherine per location) and does not require stitches.
Ipsum Diagnostics can provide the appropriate training to perform this procedure as well as the biopsy kit material (not including the local anesthetic and syringes), paperwork, specimen fixative, and appropriate packaging and shipping material.
When billing for punch biopsies for Epidermal Nerve Fiber Density Testing it is appropriate to bill code 11104 for the first biopsy, and 11105 for each additional biopsy that you perform on the patient. It is billed as a procedure, so be aware that certain insurances may not allow a procedure to be added onto an office visit on that same date (please consult your insurance providers to verify).