Glomerular basement membrane thickness in an Asian population using a novel image analysis software

Abstract

We aimed to develop an image analysis software that enabled measurement of glomerular basement membrane (GBM) thickness. With this software, we evaluated the range of GBM widths found in a cohort of Asian patients diagnosed with a spectrum of renal diseases including minimal change/IgM nephropathy, focal and segmental glomerulosclerosis, IgA nephropathy, systemic lupus erythematosus nephritis, diabetic nephropathy, pauci-immune crescentic glomerulonephritis, thin basement membrane disease, and tubulointerstitial nephritis. Measurements were taken from a minimum of five glomerular capillary loops of each glomerulus. For each loop, at least 10 different points of the GBM were measured. The average GBM width measured for minimal change disease was 347.4 +/- 9.0 nm, with the highest value being 403.9 nm and lowest being 214.7 nm. No association was found between GBM width and gender. We found a significant increase in GBM width in pathological states like lupus nephropathy (p < 0.0001), diabetic nephritis (p < 0.001) and tubulointerstitial nephritis (p < 0.01) as compared with minimal change disease. Only one case of thin membrane nephropathy (198.7 nm) was available for analysis and we found a significant thinning of the GBM. These observations provide insights into the range of GBM thickness in several disease states and support the use of this novel software in the daily diagnostic laboratory setting.