title: Serum cystatin C as a novel marker to differentiate pseudoazotemia in the setting of intraperitoneal urine extravasation.
abstract: Urinary ascites results in pseudoazotemia due to urinary creatinine reabsorption across the peritoneum. We report a case of a pyeloplasty complicated by urine extravasation, in which the diagnosis was aided by discrepant findings of an elevated serum creatinine level but a stable cystatin C level. Cystatin C is a marker of renal function but is not typically excreted into the urine and therefore can be used to differentiate pseudoazotemia from true azotemia and is a better marker of renal function in the setting of known urinary ascites. These findings are relevant for patients with potential traumatic or nontraumatic sources of urine extravasation.
authors: Department of Urology, Columbia University Medical Center, New York, NY. Electronic address: Slw2126@columbia.edu.
authors: Solomon L
authors: SL
authors: Woldu
authors: Department of Urology, Columbia University Medical Center, New York, NY.
authors: Justin T
authors: JT
authors: Matulay
authors: Department of Urology, Columbia University Medical Center, New York, NY.
authors: Mark V
authors: MV
authors: Silva
authors: Department of Urology, Columbia University Medical Center, New York, NY.
authors: Jennifer J
authors: JJ
authors: Ahn
authors: Department of Nephrology, Columbia University Medical Center, New York, NY.
authors: Ronald
authors: R
authors: Zviti
authors: Department of Urology, Columbia University Medical Center, New York, NY.
authors: Sarah M
authors: SM
authors: Lambert
authors: Department of Urology, Columbia University Medical Center, New York, NY.
authors: Shumyle
authors: S
authors: Alam
authors: Department of Urology, Columbia University Medical Center, New York, NY.
authors: Pasquale
authors: P
authors: Casale
mesh_terms: D057868:Anastomotic Leak / Q000097:blood / Q000175:diagnosis* / Q000652:urine; D001201:Ascites / Q000097:blood* / Q000209:etiology / Q000652:urine; D053099:Azotemia / Q000097:blood / Q000175:diagnosis*; D015415:Biomarkers / Q000097:blood; D001806:Blood Urea Nitrogen; D002648:Child; D003404:Creatinine / Q000097:blood; D055316:Cystatin C / Q000097:blood*; D005919:Glomerular Filtration Rate; D006801:Humans; D007668:Kidney / Q000502:physiology; D008297:Male; D014517:Ureteral Obstruction / Q000601:surgery
chemical_list: D015415:Biomarkers; D055316:Cystatin C; D003404:Creatinine