In which patients with suspected IgA nephropathy and microalbuminuria would you recommend a kidney biopsy?

There are no guidelines to answer this question. This is my approach.

In proteinuric patients, with intact kidney function, threshold proteinuria (UPCR) of 0.5 g/g, or UACR <300 mg/g would be an indication to biopsy. In diseases such as IgA Nephropathy, treatment is driven by the degree of proteinur...