Vol. 36 No. 4 (2023)

Photograph submitted to the Medical Photography and Illustration Contest of Iatreia Medical Journal.

Photograph Title: Membranous Glomerulonephritis

This photograph shows a glomerulus from a patient with membranous glomerulonephritis, displaying the characteristic spikes or projections of the basement membrane, stained with silver methenamine (original magnification 40X).

Morphologically, immune complexes deposit in the subepithelial capillary walls (outer face of the basement membrane), prompting a response from the membrane to try to encircle or surround them. In light microscopy, with silver methenamine staining, perpendicular projections can be observed on the basement membrane, consisting of material similar to it, known as spikes. These projections progressively extend and encircle or envelop the immune complexes. In tangential sections of the membrane, they appear as spaces or holes corresponding to the immune complex (an apparently empty space that does not stain with silver methenamine), completely surrounded by the basement membrane. These immune complexes, in some cases, can also be visualized by light microscopy with trichrome staining and, more specifically, by immunofluorescence.

Authors: Jeanneth Echeverri-Villegas, Julián Rondón-Carvajal