Is the Mayo prediction tool for MGRS ready for prime time?

Kidney disorders caused by a monoclonal Ig (monoclonal gammopathy of renal significance) are now considered treatable kidney diseases. Because chronic kidney disease and monoclonal gammopathy of undetermined significance occur frequently at older ages and because monoclonal gammopathy of renal significance is rare, it is difficult to select the right patient for a kidney biopsy. The "Mayo MGRS Prediction Tool" was developed to assist in decision making. Although there is some value in using the calculator, there are many caveats. Clinicians should be aware of the biases and limitations of the study before using the calculator in their routine practice.