The Incidence of Major Hemorrhagic Complications After Renal Biopsies in Patients with Monoclonal Gammopathies

Background and objectives: Monoclonal gammopathies frequently cause renal disease, but they may be an incidental finding. Assessment of renal pathology in the context of renal dysfunction and a monoclonal gammopathy therefore serves as a useful diagnostic tool and, in addition, provides prognostic information. There is, however, a theoretical risk of increased hemorrhagic complications from renal biopsies in this setting. The purpose of this study was to determine the incidence of significant hemorrhagic complications after renal biopsies in patients with monoclonal gammopathies. Design, setting, participants, & measurements: The case notes of 1993 unselected patients from four teaching hospitals within the United Kingdom who underwent native or transplant renal biopsies between 1993 and 2008 were reviewed. Subjects were categorized as having a monoclonal gammopathy or not, and the incidence of major hemorrhagic complications between groups was compared. Results: In total, 74 (3.7%) patients (native and transplant biopsies) had a major hemorrhagic complication. One hundred forty-eight subjects with a monoclonal gammopathy were identified. The complication rate in this group was 4.1% compared with 3.9% in the control population (native biopsies only; P = 0.88). Conclusions: In the population studied, the rate of major hemorrhagic complications after percutaneous renal biopsy was not significantly greater in patients with a monoclonal gammopathy. Clin J Am Soc Nephrol 5: 1977-1980, 2010. doi: 10.2215/CJN.00650110