Systematic review of the literature on reproducibility of the interpretation of renal biopsy in lupus nephritis

Objective Before using a test, it should be determined whether the results are reliable. The reliability of the interpretation of renal biopsy in patients with lupus nephritis has not been clearly elucidated. Our objective was to estimate inter and intra-observer reliability of the histological classification, as well as activity and chronicity indices in renal biopsy of patients with lupus nephritis. Methods We conducted a systematic search of the literature, which included articles in any language, using PubMed, Embase, Cochrane and Lilacs databases. Search terms included were: reproducibility, reliability, agreement, systemic lupus erythematosus and lupus nephritis. Comparative studies with any design were included, regardless of the year or the language of publication. Two investigators, independently, screened the literature published in accordance with pre-established inclusion and exclusion criteria. Results We found 13 relevant studies. Inter-observer reproducibility of most measurements was moderate or low, despite the fact that, in most cases, the readings were made by expert nephropathologists. There was great diversity among designs, participants, including samples and outcomes evaluated in different studies. Although there are too many reports on the clinical use, studies evaluating the reliability of classifications on renal biopsy in lupus nephritis are rare. The quality of the methodological design and reporting was fair. Conclusion The interpretation of renal biopsy in lupus nephritis is poorly reproducible, causing serious doubts about its validity and its clinical application. As it can lead to serious diagnosis, treatment and prognosis errors, it is necessary to intensify research in this field.