Test Id : RFCWT
Renal Pathology Tissue Consultation, Wet Tissue
Useful For
Suggests clinical disorders or settings where the test may be helpful
Evaluating and managing patients with kidney disease
Following the progression of known kidney disease or response to therapy
Determining the cause of dysfunction in the transplanted kidney (allograft)
Highlights
Our consultative practice strives to provide the highest quality diagnostic, consultative service, balancing optimal patient care with a cost-conscious approach that supports the rapid turnaround time for diagnostic results.
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 |
|---|---|---|---|
| LV4RP | Level 4 Gross and Microscopic, RB | No, (Bill Only) | No |
| SS2PC | SpecStain, Grp II, other | No, (Bill Only) | No |
| IFPCI | IF Initial | No, (Bill Only) | No |
| IHPCI | IHC Initial | No, (Bill Only) | No |
| IFPCA | IF Additional | No, (Bill Only) | No |
| EMR | EM, Renal Biopsy | No, (Bill Only) | No |
Testing Algorithm
Delineates situations when tests are added to the initial order. This includes reflex and additional tests.
Laboratory approval is required prior to ordering this test. Contact Mayo Clinic Laboratories at 800-533-1710.
The Renal Pathology Consultation is performed by a Mayo Clinic renal pathologist and entails the performance of appropriate procedures and stains based on the material received, patient information, and specific findings on the case to determine a diagnosis. Optimal/standard diagnostic interpretation of a medical kidney biopsy requires integration of the light microscopy, immunofluorescence, and electron microscopy findings together with the clinical and laboratory data for the patient. Published standards by the Renal Pathology Society are followed for the diagnostic evaluation and reporting of non-neoplastic kidney disease.(1)
Light Microscopy:
Wet/unprocessed tissue submitted for light microscopy routinely includes the preparation of stains, which include hematoxylin and eosin, periodic acid Schiff, Masson trichrome, and Jones methenamine silver stains.
Immunofluorescence:
Wet/unprocessed tissue submitted for immunofluorescence may include the following stains to render an accurate diagnosis. These stains include IgG, IgA, IgM, C1q, C3, albumin, fibrinogen, kappa light chain, and lambda light chain stains with C4d added if the biopsy is an allograft. Albumin, Fibrinogen will be sent to Mayo Clinic Laboratories (MCL)-Rochester to be performed if needed.
The IgG subtypes (IgG1, IgG2, IgG3, IgG4) are typically only utilized if the biopsy shows features suspicious for a monoclonal/monotypic deposition process involving IgG. These will be sent to MCL-Rochester to be performed if needed.
Alport (collagen IV, alpha 2, and alpha 5) staining is performed in the setting of biopsy findings that are consistent with hereditary nephritis/Alport syndrome. These will be sent to MCL-Rochester to be performed if needed.
Phospholipase A2 receptor staining is performed in the setting of membranous nephropathy/glomerulonephritis to aid in determining whether it is most likely primary/idiopathic or secondary. These will be sent to MCL-Rochester to be performed if needed.
Paraffin-Based Immunofluorescence Stains:
The paraffin-based immunofluorescence stains listed above would only be utilized in the special circumstance when there is no tissue or inadequate tissue available for standard immunofluorescence or if there are findings that raise concern for so-called "masked deposits.
Electron Microscopy:
Wet/unprocessed tissue submitted for electron microscopy will be processed for transmission electron microscopy. A formal interpretive report is issued, incorporating the findings from all tests performed for diagnostic purposes. Specimens will be sent to MCL-Rochester for electron microscopy scoping if needed.
Method Name
A short description of the method used to perform the test
Pathology Consultation
NY State Available
Indicates the status of NY State approval and if the test is orderable for NY State clients.
Reporting Name
Lists a shorter or abbreviated version of the Published Name for a test
Aliases
Lists additional common names for a test, as an aid in searching
Kidney Allograft Biopsy
Kidney Biopsy
Kidney Transplant Biopsy
Native Kidney Biopsy
RBPC
Renal Allograft Biopsy
Renal Biopsy
Renal Transplant Biopsy
Testing Algorithm
Delineates situations when tests are added to the initial order. This includes reflex and additional tests.
Laboratory approval is required prior to ordering this test. Contact Mayo Clinic Laboratories at 800-533-1710.
The Renal Pathology Consultation is performed by a Mayo Clinic renal pathologist and entails the performance of appropriate procedures and stains based on the material received, patient information, and specific findings on the case to determine a diagnosis. Optimal/standard diagnostic interpretation of a medical kidney biopsy requires integration of the light microscopy, immunofluorescence, and electron microscopy findings together with the clinical and laboratory data for the patient. Published standards by the Renal Pathology Society are followed for the diagnostic evaluation and reporting of non-neoplastic kidney disease.(1)
Light Microscopy:
Wet/unprocessed tissue submitted for light microscopy routinely includes the preparation of stains, which include hematoxylin and eosin, periodic acid Schiff, Masson trichrome, and Jones methenamine silver stains.
Immunofluorescence:
Wet/unprocessed tissue submitted for immunofluorescence may include the following stains to render an accurate diagnosis. These stains include IgG, IgA, IgM, C1q, C3, albumin, fibrinogen, kappa light chain, and lambda light chain stains with C4d added if the biopsy is an allograft. Albumin, Fibrinogen will be sent to Mayo Clinic Laboratories (MCL)-Rochester to be performed if needed.
The IgG subtypes (IgG1, IgG2, IgG3, IgG4) are typically only utilized if the biopsy shows features suspicious for a monoclonal/monotypic deposition process involving IgG. These will be sent to MCL-Rochester to be performed if needed.
Alport (collagen IV, alpha 2, and alpha 5) staining is performed in the setting of biopsy findings that are consistent with hereditary nephritis/Alport syndrome. These will be sent to MCL-Rochester to be performed if needed.
Phospholipase A2 receptor staining is performed in the setting of membranous nephropathy/glomerulonephritis to aid in determining whether it is most likely primary/idiopathic or secondary. These will be sent to MCL-Rochester to be performed if needed.
Paraffin-Based Immunofluorescence Stains:
The paraffin-based immunofluorescence stains listed above would only be utilized in the special circumstance when there is no tissue or inadequate tissue available for standard immunofluorescence or if there are findings that raise concern for so-called "masked deposits.
Electron Microscopy:
Wet/unprocessed tissue submitted for electron microscopy will be processed for transmission electron microscopy. A formal interpretive report is issued, incorporating the findings from all tests performed for diagnostic purposes. Specimens will be sent to MCL-Rochester for electron microscopy scoping if needed.
Specimen Type
Describes the specimen type validated for testing
Kidney Biopsy
Ordering Guidance
This test is for a renal wet tissue consultation only. For a renal consultation on paraffin embedded tissue and slides, order PATHC / Pathology Consultation which is performed at Mayo Clinic Laboratories-Rochester.
For test ordering guidance for other specimen types, see Pathology Consultation Ordering Algorithm.
Shipping Instructions
1. Advise shipping specimens in Styrofoam transportation coolers to avoid extreme hot or cold temperatures to ensure specimens are received at required specimen stability temperature.
2. Attach the pathology address label included in the kit to the outside of the transport container.
Necessary Information
The following information is required:
1. All requisitions must be labeled with:
-Patient name, date of birth, and medical record number
-Name and phone number of the referring pathologist or ordering physician
-Anatomic site and collection date
2. All specimens must be labeled with:
-Two patient identifiers (first and last name, date of birth, or medical record number)
-Specimen type and anatomic site
3. A brief patient history is essential to achieve a consultation fully relevant to the ordering physician's needs.
All requisition and supporting information must be submitted in English.
Specimen Required
Defines the optimal specimen required to perform the test and the preferred volume to complete testing
Specimen Type: Tissue
Supplies: Renal Biopsy Kit (T968)
Source: Kidney
Specimen Volume: Entire specimen
Collection Instructions: Collect specimens according to the instructions in Renal Biopsy Preparation Instructions.
Additional Information:
Rush (same day as receipt) interpretation is available on Saturday and holidays for clinically emergent cases (eg, acute kidney failure, rapidly progressive glomerulonephritis, acute kidney allograft dysfunction) but requires advanced notification and approval by a Mayo Clinic Renal Pathologist 904-956-3318.
To request RUSH service outside regular business hours, call 800-533-1710.
Digital Image Access
1. Information on accessing digital images for renal consult cases can be accessed through this website: https://news.mayocliniclabs.com/ihc-stains/
2. Clients ordering stains using a manual requisition form will not have access to digital images.
Special Instructions
Library of PDFs including pertinent information and forms related to the test
Forms
1. Renal Biopsy Patient Information
2. If not ordering electronically, complete, print, and send a Renal Diagnostics Test Request (T830) with the specimen.
Specimen Minimum Volume
Defines the amount of sample necessary to provide a clinically relevant result as determined by the testing laboratory. The minimum volume is sufficient for one attempt at testing.
See Specimen Required
Reject Due To
Identifies specimen types and conditions that may cause the specimen to 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 |
|---|---|---|---|
| Kidney Biopsy | Ambient (preferred) | ||
| Refrigerated | |||
Useful For
Suggests clinical disorders or settings where the test may be helpful
Evaluating and managing patients with kidney disease
Following the progression of known kidney disease or response to therapy
Determining the cause of dysfunction in the transplanted kidney (allograft)
Testing Algorithm
Delineates situations when tests are added to the initial order. This includes reflex and additional tests.
Laboratory approval is required prior to ordering this test. Contact Mayo Clinic Laboratories at 800-533-1710.
The Renal Pathology Consultation is performed by a Mayo Clinic renal pathologist and entails the performance of appropriate procedures and stains based on the material received, patient information, and specific findings on the case to determine a diagnosis. Optimal/standard diagnostic interpretation of a medical kidney biopsy requires integration of the light microscopy, immunofluorescence, and electron microscopy findings together with the clinical and laboratory data for the patient. Published standards by the Renal Pathology Society are followed for the diagnostic evaluation and reporting of non-neoplastic kidney disease.(1)
Light Microscopy:
Wet/unprocessed tissue submitted for light microscopy routinely includes the preparation of stains, which include hematoxylin and eosin, periodic acid Schiff, Masson trichrome, and Jones methenamine silver stains.
Immunofluorescence:
Wet/unprocessed tissue submitted for immunofluorescence may include the following stains to render an accurate diagnosis. These stains include IgG, IgA, IgM, C1q, C3, albumin, fibrinogen, kappa light chain, and lambda light chain stains with C4d added if the biopsy is an allograft. Albumin, Fibrinogen will be sent to Mayo Clinic Laboratories (MCL)-Rochester to be performed if needed.
The IgG subtypes (IgG1, IgG2, IgG3, IgG4) are typically only utilized if the biopsy shows features suspicious for a monoclonal/monotypic deposition process involving IgG. These will be sent to MCL-Rochester to be performed if needed.
Alport (collagen IV, alpha 2, and alpha 5) staining is performed in the setting of biopsy findings that are consistent with hereditary nephritis/Alport syndrome. These will be sent to MCL-Rochester to be performed if needed.
Phospholipase A2 receptor staining is performed in the setting of membranous nephropathy/glomerulonephritis to aid in determining whether it is most likely primary/idiopathic or secondary. These will be sent to MCL-Rochester to be performed if needed.
Paraffin-Based Immunofluorescence Stains:
The paraffin-based immunofluorescence stains listed above would only be utilized in the special circumstance when there is no tissue or inadequate tissue available for standard immunofluorescence or if there are findings that raise concern for so-called "masked deposits.
Electron Microscopy:
Wet/unprocessed tissue submitted for electron microscopy will be processed for transmission electron microscopy. A formal interpretive report is issued, incorporating the findings from all tests performed for diagnostic purposes. Specimens will be sent to MCL-Rochester for electron microscopy scoping if needed.
Clinical Information
Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test
The Mayo Renal Pathology service is staffed by board-certified pathologists who have a special interest in non-neoplastic diseases of the kidney.
Kidney biopsy has proven to be of value in the clinical evaluation and management of patients with kidney disease, including acute and chronic renal insufficiency, nephrotic syndrome, nephritic syndrome, proteinuria, and hematuria, and in the overall management of kidney transplant recipients.
Optimal interpretation of a kidney biopsy requires integration of clinical and laboratory results with light microscopic, immunofluorescent histology, and electron microscopy findings.
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.
Results of the consultation are reported in a formal pathology report, which may include a description of ancillary test results (if applicable) and an interpretive comment.
Interpretation
Provides information to assist in interpretation of the test results
Both a verbal report and a faxed report are provided to nephrologists for Mayo Clinic Laboratories cases.
Representative electron microscopy images and significant positive immunofluorescent stain findings can be provided on a CD upon request.
In most cases, the electron microscopy results are reported as an addendum, and a final report is issued including these findings. This final report is again faxed to the submitting nephrologist and mailed to the submitting pathology laboratory, along with a representative set of the light microscopy slides.
Digital images for electron microscopy and immunofluorescent stains may be downloaded as needed using the digital imaging link provided in the final report.
Cautions
Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances
Accurate and timely interpretation of a kidney biopsy requires integration of light microscopic, immunofluorescent histology, and electron microscopic findings with clinical and laboratory data. Failure to provide the relevant clinical history and laboratory results may result in a delay in the interpretation or the inability to adequately correlate the biopsy findings with the clinical picture.
Clinical Reference
Recommendations for in-depth reading of a clinical nature
1. Chang A, Gibson IW, Cohen AH, et al. A position paper on standardizing the nonneoplastic kidney biopsy report. Clin J Am Soc Nephrol. 2012; 7(8):1365-1368. doi:10.2215/CJN.02300312
2. Jennette JC, D'Agati VD, Olson JL, Silva FG, eds. Heptinstall's Pathology of the Kidney. 7th ed. Lippincott Williams and Wilkins; 2014
Method Description
Describes how the test is performed and provides a method-specific reference
Gross and microscopic examination of tissue. Ancillary testing is ordered at the discretion of the Mayo Clinic pathologist. The results of all testing will be provided in the context of the final pathology report.(Unpublished Mayo method)
PDF Report
Indicates whether the report includes an additional document with charts, images or other enriched information
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
Rush (same day as receipt) interpretation is available on weekends and holidays for clinically emergent cases (eg, acute kidney failure, rapidly progressive glomerulonephritis, acute kidney allograft dysfunction) but requires advanced notification and approval by a Mayo Clinic pathologist.
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.
Specimen Retention Time
Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded
Performing Laboratory Location
Indicates the location of the laboratory that performs the test
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 account representative. 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.
Not Applicable
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.
CPT codes are provided by the performing laboratory.
88305 (If appropriate)
88348 (If appropriate)
88313 (If appropriate)
88346 (If appropriate)
88350 (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 |
|---|---|---|
| RFCWT | Renal Pathology Tissue Consult, MCF | 65757-7 |
| 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.
|
|---|---|---|
| 620416 | Interpretation | 59465-5 |
| 620417 | Participated in the Interpretation | No LOINC Needed |
| 620418 | Report electronically signed by | 19139-5 |
| 620419 | Addendum | 35265-8 |
| 620420 | Gross Description | 22634-0 |
| 620421 | Material Received | 22633-2 |
| 620422 | Disclaimer | 62364-5 |
| 620423 | Case Number | 80398-1 |