CRP-09
CRP-09
Clinical History
The patient is an 18 year old female with a BUN of 10, creatinine of 0.6, and urinary protein of 2 g/24 hr. Prior biopsy 3-4 years ago was interpreted as consistent with minimal change disease. Now steroid dependent. Rule out focal segmental glomerulosclerosis.
Gross Description
Received in Zeus fixative are two cores measuring 9 x 1 and 7 x 2 mm in greatest dimensions. These are entirely submitted for immunofluorescence. Received in Carson's fixative are two cores measuring 9 and 7 mm in length and 1 mm in diameter. Two 1-mm pieces are taken for EM, and the remainder is submitted for light microscopy.
Pathology
Case CRP-009 H&E
Case CRP-009 PASH
Microscopic Description
Light Microscopy
The specimen consists of one small fragment of renal cortex and a larger fragment that is about half cortex and half medulla. There are 38 glomeruli in the original three levels. One of these at the corticomedullary junction is obsolete, but none of the glomeruli show segmental sclerosis. All of the glomeruli are similar and show no significant mesangial expansion or proliferation. The capillary basement membranes are unremarkable with the silver and PASH stains. There is no significant interstitial fibrosis or tubular atrophy. There are no inflammatory infiltrates. Arterioles and small arteries are unremarkable. Four additional levels were cut and stained with PASH. These yielded eight more glomeruli, which are all similar to those described above and show essentially normal morphology and no segmental sclerosis.
Immunofluorescence
There are 12 glomeruli in the sections. None of these are obsolete, and none show segmental sclerosis. There is diffuse l+ mesangial staining for IgM, but stains for IgG, IgA, Clq, C3 and light chains are negative. There is no staining of the tubular basement membranes or vessels.
Electron Microscopy
Two thick sections containing a total of four glomeruli are available. These are similar to those described above and show normal morphology. Ultrastructural examination reveals no significant expansion of the mesangium, and there is no hypercellularity. Capillary basement membranes show no thickening, although there is diffuse effacement of the visceral epithelial cell foot processes. No electron dense deposits are identified.