Evaluation of acute kidney injury among hospitalized patients

ATN: acute tubular necrosis; AKI: acute kidney injury; GFR: glomerular filtration rate; SPEP: serum protein electrophoresis; UPEP: urine protein electrophoresis.
* For patients who are at higher risk for multiple myeloma, we also check SPEP, UPEP with immunofixation, and a serum free light chain assay. Higher-risk patients include all patients >40 years who have no other obvious cause for increased creatinine.