Related Experiment Video
Updated: Aug 19, 2026
Supervised Machine Learning for Semi-Quantification of Extracellular DNA in Glomerulonephritis
Published on: June 18, 2020
Methenamine silver staining quantitative digital histochemistry in chronic allograft nephropathy
1The Dokuz Eylul University School of Medicine, Izmir, Turkey.
Abstract:
Renal function and final outcome of renal allografts have been correlated with irreversible damage. This study describes a quantitative histochemical method relying on periodic acid methenamine silver (PAMS) staining of all renal compartments. Among 60 renal allograft biopsies from 43 patients, 15 biopsies showing pure chronic allograft nephropathy were selected to determine PAMS-stained area percentage (SAP), using image analysis with quantitative histochemistry. Of the 15 cases, 9 (60%) were grade I and 6 (40%) were grade II chronic allograft nephropathy (CAN). The mean serum creatinine (sCr) value was 1.86 +/- 0.47 for allograft biopsies. The mean (+/-SD) SAP for the implantation biopsies was 10.58 +/- 1.87%, and for allograft biopsies 25.26 +/- 9.67 (P <<.000). The serum creatinine (sCr) values for grade I versus II CAN were 1.63 +/- 0.24 versus 2.20 +/- 0.54 mg/dL, respectively (P=.019), and SAP values were 18.97 +/- 0.24 versus 34.7 +/- 5.89 (P=.003). There was a strong positive correlation between sCr values and SAP (P=.005; r=0.64). These findings show the PAMS approach to be a useful alternative method for reflecting damage in more than one compartment of the renal tissue. Also, the method can discriminated implantation and allograft biopsies as well as grade I and II CAN cases. The series is small for a multivariate analysis of the value of SAP measurements in PAMS-stained sections as a prognosticator, but the data support its use.
Insights
A new quantitative histochemical method using periodic acid methenamine silver (PAMS) staining effectively measures renal allograft damage. This PAMS-stained area percentage (SAP) correlates with serum creatinine levels and distinguishes between chronic allograft nephropathy (CAN) grades.
Area of Science:
- Nephrology
- Histopathology
- Quantitative Histochemistry
Background:
- Renal allograft function and outcomes are linked to irreversible tissue damage.
- Assessing this damage quantitatively is crucial for patient management.
Purpose of the Study:
- To evaluate a quantitative histochemical method using periodic acid methenamine silver (PAMS) staining for assessing renal allograft damage.
- To correlate PAMS-stained area percentage (SAP) with serum creatinine (sCr) levels and chronic allograft nephropathy (CAN) severity.
Main Methods:
- A quantitative histochemical method utilizing PAMS staining was applied to 15 renal allograft biopsies with chronic allograft nephropathy (CAN).
- Image analysis was used to determine the PAMS-stained area percentage (SAP).
- SAP values were compared between implantation and allograft biopsies, and between CAN grades I and II, and correlated with serum creatinine (sCr).
Main Results:
- The mean SAP was significantly higher in allograft biopsies (25.26%) compared to implantation biopsies (10.58%).
- Higher SAP values (34.7%) and sCr levels (2.20 mg/dL) were observed in Grade II CAN compared to Grade I (SAP 18.97%, sCr 1.63 mg/dL).
- A strong positive correlation was found between sCr values and SAP (r=0.64).
Conclusions:
- The PAMS staining method provides a quantitative assessment of damage across multiple renal compartments.
- This method effectively differentiates implantation and allograft biopsies and grades of CAN.
- SAP measurements show potential as a prognostic indicator for renal allograft health.
