Modified PASM-Masson Staining in a Renal Biopsy

Summary

In this study, we present a protocol of PASM-Masson dual staining to identify the location and extent of glomerular immune complex deposition in renal diseases.

Abstract

Special histochemical staining is an important method for a renal biopsy, which includes PAS staining, periodic acid silver methenamine (PASM) staining, and Masson staining. In this study, we aim to develop and modify the method of PASM and Masson double staining (PASM-Masson) in a renal biopsy. One hundred and fifty-two cases of renal biopsy were detected by PASM-Masson staining in our hospital. The results showed that the background of the slices was clean, and the renal structures were more visible under the microscope. The glomerular basement membrane, renal tubular basement membrane, and capillary basement membrane were stained black or brown; the mesangium and collagen fibers were stained blue black; the renal tubular epithelial cells and immune complexes were dyed red. These findings indicate that the glomerular immune complex deposition can be accurately identified and positioned by modified PASM-Masson staining, which might have important effects on the pathological diagnosis of renal diseases.

Introduction

Special histochemical staining has been used by pathologists to assist in tissue-based diagnoses for over 100 years^1,2. The application of special staining in the diagnosis of renal diseases has been recognized as an important method for distinguishing the types of renal diseases and displaying some special components in renal tissues³.

To date, a variety of special stains have been applied to renal biopsies, which includes periodic acid silver methenamine (PASM) staining and Masson's trichrome staining. Lesions of the glomerular capillary walls are the m....

Protocol

The protocol follows the guidelines of our hospital's human research ethics committee. One hundred and fifty-two cases of renal biopsy specimens were collected from the Department of Pathology at the Shenzhen Third People's Hospital (The Second Affiliated Hospital of Southern University of Science and Technology) from January 2018 to May 2019.

1. Material preparation

1. Fix all tissues with 4% neutral buffered formaldehyde (pH 7.0) for 24 h.
2. Dehydrate the fixed tissu.......

Discussion

Pathological diagnosis is an important tool for the diagnosis and differential diagnosis of renal diseases, and it is of great significance for the guidance of treatment and predicted value of renal diseases^10,11,12. Special staining is an essential method for renal biopsy including PAS staining, PASM staining and Masson staining^3,13,14.......

Materials

Name	Company	Catalog Number	Comments
Absolute ethyl alcohol	Guanghua company (Guangzhou city, China)	1.17113.023
Bouin's fixed solution	Kaixiu company (Guangzhou city, China)	20180627	Sealing
Dimethylbenzene	Sinopharm Chemical Reagent limited corporation, China	20180607
Ethyl alcohol (75%)	Likang company (Nanchang city, China)	20180915
Ethyl alcohol (95%)	Likang company (Nanchang city,China)	20181005
Glacial acetic acid	Lingfeng company (Shanghai city, China)	20170912
Hematoxylin staining solution	BASO company (Zhuhai city, China)	718101
Masson kit	Weigxi company (Guangzhou city, China)	18121101	Store at 4°C
PASM kit	BASO company (Zhuhai city, China)	618091	Store at 4°C