Test Catalog

Test Id : PNBX

Peripheral Nerve Pathology Consultation

Useful For
Suggests clinical disorders or settings where the test may be helpful

Evaluating diseases of the nerve and disorders that affect nerve function

Reflex Tests
Lists tests that may or may not be performed, at an additional charge, depending on the result and interpretation of the initial tests.

Test Id Reporting Name Available Separately Always Performed
SS2PC SpecStain, Grp II, other No, (Bill Only) No
COSPC Consult, Outside Slide No, (Bill Only) No
CUPPC Consult, w/USS Prof No, (Bill Only) No
CRHPC Consult, w/Comp Rvw of His No, (Bill Only) No
NTFPC Teased Fiber No, (Bill Only) No
IHPCI IHC Initial No, (Bill Only) No
IHPCA IHC Additional No, (Bill Only) No
LV4RP Level 4 Gross and Microscopic, RB No, (Bill Only) No
CSPPC Consult, w/Slide Prep No, (Bill Only) No
EM Electron Microscopy Yes, (Bill Only) No

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 at an additional charge. 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, methyl violet stain, Masson's trichrome stain, leukocyte common antigen, luxol fast blue/PAS stain, KP-1 macrophage, methylene blue stain, hematoxylin and eosin stain, and Turnbull blue stain or Perl’s Prussian blue 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.

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

Method Name
A short description of the method used to perform the test

Nerve Biopsy Surgical Pathology Consultation and Review of Outside Material

NY State Available
Indicates the status of NY State approval and if the test is orderable for NY State clients.

Yes

Reporting Name
Lists a shorter or abbreviated version of the Published Name for a test

Peripheral Nerve Path Consult

Aliases
Lists additional common names for a test, as an aid in searching

NPPC

PNBX

Nerve Biopsy

Neuropathology Consultation

Neuropathology Examination of Tissue

Sural Nerve Biopsy

Vasculitis

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 at an additional charge. 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, methyl violet stain, Masson's trichrome stain, leukocyte common antigen, luxol fast blue/PAS stain, KP-1 macrophage, methylene blue stain, hematoxylin and eosin stain, and Turnbull blue stain or Perl’s Prussian blue 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

Varies

Additional Testing Requirements

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

Examples:

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

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

Necessary Information

Nerve Biopsy Patient Information (T458) is required, containing the following information

1. Tentative clinical diagnosis

2. Name of nerve biopsied

3. Date of biopsy

4. Indication for nerve biopsy

 

A copy of the Neurology Clinical Notes and electromyography (EMG) results are also required for testing. Testing may be delayed if this information is not provided.

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

Forms

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 Type Temperature Time Special Container
Varies Refrigerated (preferred)
Frozen

Useful For
Suggests clinical disorders or settings where the test may be helpful

Evaluating diseases of the nerve and disorders that affect nerve function

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 at an additional charge. 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, methyl violet stain, Masson's trichrome stain, leukocyte common antigen, luxol fast blue/PAS stain, KP-1 macrophage, methylene blue stain, hematoxylin and eosin stain, and Turnbull blue stain or Perl’s Prussian blue 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.

Clinical Information
Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test

Nerve biopsies provide information about nerve fibers and the interstitium of the nerve. Neuropathic abnormalities include decreased density of myelinated fibers, segmental demyelination, and axonal degeneration. Some possible interstitial abnormalities that affect nerves include necrotizing vasculitis and amyloidosis.

 

This consultation is for fixed tissue, slides, or blocks.

Reference Values
Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.

An interpretive report will be provided.

Interpretation
Provides information to assist in interpretation of the test results

The clinical and neurological history is reviewed with the interpretation of the biopsy.

 

The histologic slides, special stains, and history, along with the physician's report are correlated by a neuromuscular pathologist. An interpretive report will be provided.

Cautions
Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances

Poor fixation, orientation, and improper handling of the nerve tissue may hinder the neuromuscular pathologist's interpretation of the biopsy. See directions for Nerve Biopsy Specimen Preparation in Special Instructions. Kits containing the proper tissue fixatives and buffers are available upon request.

Clinical Reference
Recommendations for in-depth reading of a clinical nature

1. Tracy JA, Dyck PJ, Klein CJ, Engelstad JK, Meyer JE, Dyck PJB: Onion-bulb patterns predict acquired or inherited demyelinating polyneuropathy. Muscle Nerve. 2019 Jun;59(6):665-670

2. Xu M, Pinto M, Sun C, et al: Expanded teased nerve fibre pathological conditions in disease association. J Neurol Neurosurg Psychiatry. 2019 Feb;90(2):138-140

3. Dyck PJB, Spinner RJ, Amrami KK, Klein CJ, Engelstad JK, Dyck PJ: MRI-targeted fascicular nerve biopsies of proximal nerves: historic reports and illustrative case reports. In: Dyck PJ, Dyck PJB, Engelstad JK, et al, eds. Companion to Peripheral Neuropathy: Illustrated Cases and New Developments. Elsevier; 2010:3-14

4. Dyck PJ, Dyck PJB, Engelstad J: Pathologic alterations of nerves. In: Dyck PJ, Thomas PK, eds. Peripheral Neuropathy, Vol. 1. 4th ed. Elsevier; 2005:733-829

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

Method Description
Describes how the test is performed and provides a method-specific reference

A battery of special stains and teased nerve fiber analysis will be performed if fixed tissue is provided. Nerve morphometry and electron microscopy to determine diameter size histograms and ultrastructural abnormalities may be performed based on a preliminary review by the neuropathologist.(Unpublished Mayo method)

PDF Report
Indicates whether the report includes an additional document with charts, images or other enriched information

No

Day(s) Performed
Outlines the days the test is performed. This field reflects the day that the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time before the test is performed. Some tests are listed as continuously performed, which means that assays are performed multiple times during the day.

Monday through Friday

Report Available
The interval of time (receipt of sample at Mayo Clinic Laboratories to results available) taking into account standard setup days and weekends. The first day is the time that it typically takes for a result to be available. The last day is the time it might take, accounting for any necessary repeated testing.

7 to 14 days

Specimen Retention Time
Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded

Material made at Mayo Clinic may be retained at Mayo Clinic indefinitely.

Performing Laboratory Location
Indicates the location of the laboratory that performs the test

Rochester

Fees
Several factors determine the fee charged to perform a test. Contact your U.S. or International Regional Manager for information about establishing a fee schedule or to learn more about resources to optimize test selection.

  • Authorized users can sign in to Test Prices for detailed fee information.
  • Clients without access to Test Prices can contact Customer Service 24 hours a day, seven days a week.
  • Prospective clients should contact their Regional Manager. For assistance, contact Customer Service.

Test Classification
Provides information regarding the medical device classification for laboratory test kits and reagents. Tests may be classified as cleared or approved by the US Food and Drug Administration (FDA) and used per manufacturer instructions, or as products that do not undergo full FDA review and approval, and are then labeled as an Analyte Specific Reagent (ASR) product.

This test was developed, and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the US Food and Drug Administration.

CPT Code Information
Provides guidance in determining the appropriate Current Procedural Terminology (CPT) code(s) information for each test or profile. The listed CPT codes reflect Mayo Clinic Laboratories interpretation of CPT coding requirements. It is the responsibility of each laboratory to determine correct CPT codes to use for billing.

CPT codes are provided by the performing laboratory.

88305-(if appropriate)

88313-(if appropriate)

88321-(if appropriate)

88323-(if appropriate)

88323-26-(if appropriate)

88325-(if appropriate)

88362-(if appropriate)

88348-(if appropriate)

88342-(if appropriate)

88341-(if appropriate)

LOINC® Information
Provides guidance in determining the Logical Observation Identifiers Names and Codes (LOINC) values for the order and results codes of this test. LOINC values are provided by the performing laboratory.

Test Id Test Order Name Order LOINC Value
PNBX Peripheral Nerve Path Consult In Process
Result Id Test Result Name Result LOINC Value
Applies only to results expressed in units of measure originally reported by the performing laboratory. These values do not apply to results that are converted to other units of measure.
601774 Interpretation 59465-5
601775 Participated in the Interpretation No LOINC Needed
601776 Report electronically signed by 19139-5
601777 Addendum 35265-8
601778 Gross Description 22634-0
601779 Material Received 81178-6
601912 Disclaimer 62364-5
601823 Case Number 80398-1

Test Setup Resources

Setup Files
Test setup information contains test file definition details to support order and result interfacing between Mayo Clinic Laboratories and your Laboratory Information System.

Excel | Pdf

Sample Reports
Normal and Abnormal sample reports are provided as references for report appearance.

Normal Reports | Abnormal Reports

SI Sample Reports
International System (SI) of Unit reports are provided for a limited number of tests. These reports are intended for international account use and are only available through MayoLINK accounts that have been defined to receive them.

SI Normal Reports | SI Abnormal Reports