ATUBULAR GLOMERULAR CYSTS IN HUMAN CHRONIC ALLOGRAFT NEPHROPATHY

 

RJ Barnetsonl, GBM Lindop1, IW Gibson2

1 Department of Pathology, Western Infirmary, Glasgow, UK

2 Department of Pathology, University of Manitoba, Canada

 

BACKGROUND:

We have previously shown by SEM studies that disconnection of the glomerulus from

the proximal tubule with formation of atubular glomerulor cysts is an important component of nephron loss in chronic allograft nephropathy (CAN). Their recognition by light microscopy may therefore be useful in the assessment of the extent of renal damage in renal allograft biopsies.

 

AIMS:

To use serial light microscopy sections to describe the histological features of atubular glomerular cysts, in order to recognise them on a single random section.

 

MATERIALS AND METHODS:

We studied l00 serial sections of 2 adult human kidneys, 1 post-mortem native kidney and 1 transplant nephrectomy with Banff grade III CAN.

 

RESULTS:

For both kidneys, about 10-15% of glomeruli showed cystic expansion of Bowman's space. Serial sections confirmed that these glomerular cysts had no tubular connection. Other distinctive morphological features of atubular glomerular cysts were: a contracted capillary tuft remnant with open capillary loops; a population of rounded cells within Bowman's space floating in proteinaceous cast; calcification within the proteinaceous cast; focal or global periglomerular fibrosis and thickening of Bowman's capsule with a pad of fibrocellular tissue sealing the proximal tubular orifice.

 

CONCLUSIONS:

Formation of atubular glomerular cysts is a significant pathway of irreversible glomerular damage in CAN. We have used serial sections to identify their characteristic histological features. This should enable their recognition in random renal biopsy sections. Atubular glomerular cysts should be taken into account in assessing chronic glomerular damage in allograft biopsies with CAN.

 

 

 

Details of authors:

 

1.  Dr. Robert J. Barnetson

Specialist Registrar

Department of Pathology

Western Infirmary

GLASGOW

United Kingdom

Tel:  +44 141 211 2473

Email:  rjb@mailbox.co.za

 

Dr George B M Lindop

Consultant Histopathologist

Department of Pathology Western Infirmary

GLASGOW

United Kingdom

Tel:  +44 141 211 2473

Email:  gb11s@clinmed.gla.ac.uk

 

Dr. Ian Gibson

Associate Professor

Department of Pathology

MS4-Thorlakson Building

Health Science Centre

820 Sherbrook Street

WINNIPEG, R3A 1R9

Manitoba

Canada

Email:  igibson@exchange.hsc.mb.ca