Percutaneous renal biopsy, a 26 years analysis: complications rate and risk factors.

Percutaneous renal biopsy is an invasive procedure that can result in major and minor complications. The objective of this study was to Know the frequ ency and type of complications in relation with this procedure, as well as the efficacy to obtain enough material for diagnosis. Methods. Retrospectiv e study. We review the charts of patients to whom a percutaneous renal biop sy of native Kidneys was done between January 1970 and March 1996. The foll owing data were obtained. age, gender, clinical and histopathological diagn osis, complications associated with the procedure (minor: hematuria, local infections, hematoma; major: transfusions, severe infections, surgery, neph rectomy, arteriography, embolism and death). Results. We analyzed 1,005 ren al biopsies in 840 patients, mean age 37.7 +/- 13.1 years, 67% female. Ther e were no complications in 88.8% (893 biopsies), minor complications in 8.6 5% (87 biopsies) and only in 2.4% of the procedures major complications. We divided the cases in two groups: percutaneous renal biopsy without complic ations (n = 893, 89%) and with complications (n = 112, 11%). The most frequ ent complications were hematuria (91 cases, 9.1%) and perirenal hematoma (2 9 cases, 2.7%). In these cases transfusion was required in 2.4% (26). Infec tious complications were: urosepsis in 7 cases (0.7%), bacteremia, sepsis a nd perirenal abscesses (I case each, 0.1%). One patient died because of mul tiple complications (0.1%). We observed greater risk of major complications on patients in those who biopsy was done because of acute renal failure (O R 4.03, p < 0.003). Discussion. In our experience percutaneous renal biopsy is a low risk procedure. Most complications are minor and without clinical repercussion. There must be a strict selection criteria of the patients to whom percutaneous renal biopsy is going to be done because of the risk of severe complications.