These key learning points summarize the consensus- and evidence-based recommendations included in this edition. The sources listed here for each statement recommend that physicians perform or implement these actions directly in a clinical setting.

1. For evaluation of glomerulonephritis (GN) in adults, measure protein and creatinine on a 24-hour urine collection. An alternative is collection of an “intended” 24-hour urine sample and calculation of a protein to creatinine ratio from an aliquot obtained from the sample. For evaluation of GN in children, obtain a first morning protein to creatinine ratio.
Evidence rating: SORT C
Source: Kidney Disease: Improving Global Outcomes (KDIGO), reference 10
Website: https://www.kidney-international.org/article/S0085-2538(21)00562-7/fulltext

2. In adults with kidney cysts detected incidentally on ultrasound that do not meet criteria for simple cysts (ie, distinct wall, no internal echoes, posterior enhancement), obtain multiphase, cross-sectional abdominal imaging (computed tomography and/or magnetic resonance imaging [MRI] with contrast) for further evaluation.
Evidence rating: SORT C
Source: Holcomb and Ashcraft’s Pediatric Surgery (7th ed), reference 42

3. For adults with kidney masses, obtain multiphase, cross-sectional abdominal imaging, preferably with MRI. If malignancy is suspected, also obtain chest imaging to detect possible metastatic disease.
Evidence rating: SORT C
Sources: American Urological Association (AUA), Abdom Imaging, references 40 and 80
Websites: https://www.auajournals.org/doi/10.1097/JU.0000000000001911
https://link.springer.com/article/10.1007/s00261-014-0074-4