Observational Study
Copyright ©The Author(s) 2016. Published by Baishideng Publishing Group Inc. All rights reserved.
World J Nephrol. Sep 6, 2016; 5(5): 461-470
Published online Sep 6, 2016. doi: 10.5527/wjn.v5.i5.461
Immunofluorescence on paraffin embedded renal biopsies: Experience of a tertiary care center with review of literature
Geetika Singh, Lavleen Singh, Ranajoy Ghosh, Devajit Nath, Amit Kumar Dinda
Geetika Singh, Lavleen Singh, Ranajoy Ghosh, Devajit Nath, Amit Kumar Dinda, Department of Pathology, All India Institute of Medical Sciences, New Delhi 110029, India
Author contributions: Singh G conceptualized the study, standardized the technique, wrote and critically reviewed the manuscript; Singh L compiled data and wrote the manuscript under guidance of Dr. Geetika Singh; Ghosh R and Nath D helped in standardization of technique; Dinda AK critically reviewed and edited the manuscript.
Institutional review board statement: This study was not required to provide institutional review board statement because the material used were fresh frozen tissue.
Informed consent statement: This study was not required to provide informed consent statement because the material used were fresh frozen tissue.
Conflict-of-interest statement: None.
Open-Access: This article is an open-access article which was selected by an in-house editor and fully peer-reviewed by external reviewers. It is distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/
Correspondence to: Geetika Singh, MD, Assistant Professor of Pathology, Dr BRAIRCH, Department of Pathology, All India Institute of Medical Sciences, Room No. 1084, First Floor, Teaching Block, New Delhi 110029, India. ggmed22@gmail.com
Telephone: +91-99-71911459 Fax: +91-011-26588663
Received: January 17, 2016
Peer-review started: January 18, 2016
First decision: February 29, 2016
Revised: July 16, 2016
Accepted: August 17, 2016
Article in press: August 19, 2016
Published online: September 6, 2016
Processing time: 227 Days and 17.7 Hours
Abstract
AIM

To describe the technique of immunofluorescence on paraffin embedded tissue sections and discuss the potential pitfalls with an in depth review of literature.

METHODS

Immunofluorescence is integral to diagnostic renal pathology. Immunofluorescence on paraffin embedded renal biopsies (IF-P) after enzyme treatment has been described in literature, however has not found widespread use in renal pathology laboratories. In our laboratory proteinase K digestion of paraffin embedded renal biopsy material was standardized and applied prospectively in cases where immunofluorescence on fresh frozen tissue was non contributory or not possible. Diagnostic utility was assessed and in a cohort of cases comparison of intensity of staining with routine immunofluorescence was performed.

RESULTS

Over the 5-year study period, of the 3141 renal biopsies received IF-P was performed on 246 cases (7.7%) and was interpretable with optimal digestion in 214 cases (6.8%). It was of diagnostic utility in the majority of cases, which predominantly included glomerular disease. Non-diagnostic IF-P was found in membranous nephropathy (2 of 11 cases), membranoproliferative glomerulonephritis (2 of 32 cases), lupus nephritis (1 of 25 cases), post infectious glomerulonephritis (1 of 11 cases) and chronic glomerulonephritis (3 of 8 cases). Comparing cases with both routine IF and IF-P, 35 of 37 showed either equal intensity or a minor difference in intensity of staining (1+) for the diagnostic immunoglobulin/complement. Technically assessment of immunofluorescence on the paraffin embedded tissue was found to be easier with clearly observed morphology, however a false positive staining pattern was observed in under-digested tissue.

CONCLUSION

As a “salvage” technique, immunofluorescence on paraffin embedded renal biopsies is of great diagnostic utility, however not without pitfalls.

Keywords: Immunofluorescence on paraffin section; Renal biopsy; Salvage technique; Enzymatic digestion; Proteinase K

Core tip: Immunofluorescence on formalin fixed paraffin embedded tissue is a useful “salvage” technique for renal diagnostic pathology, in case of non-availability of representative fresh frozen tissue. This article describes the technique of immunofluorescence on paraffin embedded tissue sections, discusses the potential pitfalls with an in depth review of literature.