Glomerular Filtration Rate and Renal Volume in Dogs with Congenital Portosystemic Vascular Anomalies before and after Surgical Ligation

Abstract

Glomerular filtration rate (GFR) and renal volume were evaluated in dogs with confirmed portosystemic vascular anomalies (PSVA) before and after surgical ligation of their PSVA. Pre- and postligation CBC, serum biochemistry, urinalysis, abdominal ultrasonography with measurement of renal volume, and per rectal scintigraphy were performed to document resolution of abnormalities consistent with portosystemic shunting. GFR was estimated by plasma 99mTc-diethylenetriaminepentaacetic acid (99mTc-DTPA) clearance before (n = 21) and after (n = 12) surgical correction of PSVA. Preligation 99mTc-DTPA GFR was increased (median, 5.64 mL/minute/kg; range, 3.53-8.49 mL/minute/kg; reference range, 2.83-4.47 mL/minute/kg) in 81% (17/21) of dogs. Postligation 99mTc-DTPA GFR decreased in all 12 evaluated dogs (median change = -42%; P < .001). Preligation renal volume was above the reference range for the left and right kidneys in 71% (10/14) and 69% (11/16) of dogs evaluated, respectively. Right renal volume decreased significantly (n = 5; median change, -45%; P = .03) after surgical ligation of PSVA. These findings document increased GFR and renal volume in dogs with PSVA, which may explain in part the low blood urea nitrogen and serum creatinine concentrations encountered in these dogs. Knowledge of changes in GFR associated with PSVA ligation may prove helpful in the anesthetic, drug, and dietary management of affected dogs.

Neutrophil gelatinase‐associated lipocalin in dogs with chronic kidney disease, carcinoma, lymphoma and endotoxaemia

“…Diagnosis of systemic hypertension (systolic blood pressure ≥160 mm Hg) was also noted. Upon identifying dogs with suspected CKD for possible enrolment in the present study, GFR was measured by plasma technetium clearance and those dogs that had a reduced GFR (<2·83 mL/minute/kg; institutional reference interval 2·83 to 4·47 mL/minute/kg) remained in the study (Deppe et al 1999 ). On the days that GFR was performed, blood and urine samples were obtained before administration of technetium.…”

Water Metabolism and Diabetes Insipidus

“…The exact cause of the polyuria is not known but may involve loss of medullary hypertonicity secondary to impaired urea nitrogen production or altered renal blood flow, increased GFR and ultrafiltrate volume, hypokalemia, impaired metabolism of cortisol, and primary polydipsia (Deppe et al, 1999). Many of the metabolic causes of polyuria and polydipsia (e.g., diabetes mellitus, hyperadrenocorticism, hypercalcemia) secondarily affect the liver, making it difficult to determine the role of the liver in causing polyuria and polydipsia.…”

Creatinine in the Dog: A Review

“…A moderate decrease in P‐creatinine was reported in 80% of dogs with portosystemic shunts 229 or dogs with a surgically placed portocaval shunt, 230 whereas it was unchanged in dogs after surgical portocaval anastomosis associated with periarterial neurectomy 231 . A decrease also was noted in early babesiosis 232 …”