Actual practices in nephropathology: a survey and comparison with best practices

Nephropathology is a specialized field requiring routine tissue evaluation by immunofluorescence (IF), electron microscopy (EM), and light microscopy, and has published standards of best practice. Actual practices are less well documented. We therefore evaluated actual practices in nephropathology and their divergence from best practices. One hundred and twenty Renal Pathology Society members were given questionnaires regarding tissue handling, processing, and staining. Appropriate statistics for each question were calculated from results compiled into Microsoft Excel. Responses from 75 members showed that most received 16 or 18 gauge core biopsies, examined 9 slides for native kidneys, 8 slides for transplant kidneys, and for both used hematoxylin and eosin, periodic acid-Schiff, trichrome, and silver stains. For native kidney biopsies, most collected for IF and EM if tissue was adequate, while clinical input could influence the rest. Almost all performed IF on adequate samples, with a minimum of 8 antibodies, including both light chains, those from Europe sometimes without proof of adequacy. Half performed EM unconditionally, the remainder based on specimen adequacy or clinical input. For transplant kidney biopsies, most collected tissue for IF and EM only with specific clinical indications, performed C4d IF on frozen tissue if available, but few used the native kidney IF panel. Very few performed EM unconditionally, but most would if given specific indications. We conclude that actual nephropathology practices within the Renal Pathology Society are geographically uniform and similar to published best practices, with divergence in performing IF and EM on the basis of specimen adequacy and clinical input, particularly in transplant biopsies.