Test Catalog

Test ID: PNBX    
Peripheral Nerve Pathology Consultation

Testing Algorithm Delineates situations when tests are added to the initial order. This includes reflex and additional tests.

A battery of enzyme histochemical stains or immunostains are performed; other tests can be performed as indicated and will be charged separately.  The reviewing neuromuscular pathologist will determine the need for additional testing.


Wet tissue for consultation: When adequate tissue is provided, routine testing will include: teased fiber examination, Congo red stain, Turnbull blue stain, methyl violet stain, Masson's trichrome stain, leukocyte common antigen, luxol fast blue/PAS stain, KP-1 macrophage, methylene blue stain, and hematoxylin and eosin stain.


Slides and blocks sent for consultation: Special stains and studies performed on the case should be sent with the case for review. In order to determine an accurate diagnosis, some of these stains or studies may be deemed to warrant repeat testing at an additional charge at the discretion of the reviewing Mayo Clinic neuromuscular pathologist. In addition, testing requested by the referring physician (immunostains, molecular studies, etc) may not be performed if deemed unnecessary by the reviewing Mayo Clinic neuromuscular pathologist. For all consultations, ancillary testing necessary to determine a diagnosis is ordered at the discretion of the Mayo Clinic neuromuscular pathologist. An interpretation, which includes an evaluation of the specimen and determination of a diagnosis, will be provided within a formal pathology report.


See Pathology Consultation Ordering Algorithm in Special Instructions.

Specimen Type Describes the specimen type validated for testing


Additional Testing Requirements

Biopsies from same site will be processed as 1 specimen. Biopsies from different sites require separate orders and separate specimen vials.


1. 3 segments (vials) of left sural nerve are processed as 1 specimen, 1 order number.

2. 1 left sural nerve and 1 left superficial peroneal nerve requires 2 separate orders.

Necessary Information

1. Tentative clinical diagnosis

2. Name of nerve biopsied

3. Date of biopsy

4. Indication for nerve biopsy

Specimen Required Defines the optimal specimen required to perform the test and the preferred volume to complete testing

Supplies: Nerve Biopsy Specimen Prep Instruction (T580)

Specimen Type: Nerve biopsy tissue, slides, or block

Collection Instructions: Prepare and transport specimen per instructions in Nerve Biopsy Specimen Preparation Instruction (T580) in Special Instructions. A Nerve Biopsy Kit (call 507-284-8065 to order) containing fixatives and buffer is available for an additional fee.

Special Instructions Library of PDFs including pertinent information and forms related to the test


1. Pathology/Cytology Information (T707) in Special Instructions

2. Nerve Biopsy Patient Information (T458) in Special Instructions

Reject Due To Identifies specimen types and conditions that may cause the specimen to be rejected

No specimen should be rejected.

Specimen Stability Information Provides a description of the temperatures required to transport a specimen to the performing laboratory, alternate acceptable temperatures are also included

Specimen TypeTemperatureTimeSpecial Container
VariesRefrigerated (preferred)