Handling of renal biopsies: different approaches reflect a lack of evidence for what constitutes “best practice”

We read ACP Best Practice No 160 “Renal biopsy specimens” with interest.¹ Dr Furness rightly avoids providing a list of specific procedures to follow because, as he points out “there is a need to assess each case on its merits, rather than following rigid rules”. It is clear from an audit of handling of renal biopsies in the UK, performed in 1999, that standard operative procedures vary widely, and that many laboratories fall short of “best practice”. A probable reason for this is that there is very little hard evidence to support any specific recommendations. In the UK audit, a questionnaire was circulated to all members of the UK Renal Pathology Group and returns were received from 50% of the 54 laboratories represented. It is interesting to compare current practices with Dr Furness's guidelines.

Dr Furness recommended that all specimens should be examined in the biopsy room for adequacy, using a dissecting microscope. However, in only 15% of units is this performed as routine. Failure to confirm the presence of renal cortex in the specimen would be expected to increase dramatically the proportion of inadequate biopsies. This was not the experience in Manchester, however, where in 1994, as a result of staff shortages, the practice of sending an MLSO to attend every biopsy procedure was stopped.² In Oxford, the histopathology laboratory is on a different site to the renal and transplant units; neither an MLSO nor a pathologist attends biopsies, as was once the case. Furthermore, what constitutes an adequate specimen is difficult to define and to some extent depends on …