Do you rule out active urinary tract infections prior to performing a kidney biopsy?

The 2 infectious reasons to avoid a renal biopsy are- active kidney infection and active skin infection at the site of the biopsy (Luciano & Moeckel, PMID 30661724).

Perinephric hematoma is common after a kidney biopsy and there is a report in the literature where this has gotten infected in the presence of an asymptomatic UTI. This leads to septicemia and death of the patient (Samellas, PMID 14139609, Rosenbaum et al., PMID 682429).

The mechanism is as follows:

• communication of the hematoma with an infected collecting system
• clots obstructing the flow of urine, &
• trauma to the kidney which contributes to the spread of infection.

However, the overall risk of infection is very low, 0.2%. Therefore, some suggest ruling out a UTI is not required...

I think we should. I would not want to biopsy a possible infected kidney.

However, interpreting the results may be tricky. For example, a lupus patient may have pyuria and hematuria but that does not automatically mean an infection, and that does not prevent me from biopsying them.