Ultrasonographic Evaluation of Kidney Damage in Dog with Gentamicin Nephrotoxicity

Authors: Kürşat TURGUT, Mehmet MADEN, İsmail ŞEN, M. Kemal ÇİFTÇİ

Abstract: Acute tubular necrosis was induced by experimental gentamicin nephrotoxicity to follow and describe the changes in ultrasonographic appearance of the kidney. Sonograms were evaluated for information on size, shape and renal structure, specifically including focal, multifocal, or diffuse alterations in renal cortical, medullar, sinusal and perinephric echogenity and intensity (compared to that of the splenic and hepatic paranchmys). Following 12 hours of no feeding, clinical, biochemical and ultrasonographic examinations were conducted and then gentamicin sulphate (10 mg/kg body weight, t.i.d.) was injected for 10 consecutive days. The clinical states of the dogs were observed, and urine dip stick examinations, microscopic examination of urine sediment, biochemical [blood: BUN, serum creatinine (CR), albumin PO4-,Na+,K+ concentrations; urine: total protein (TP) and creatinine concentrations, N-acetyl-b-D-glucosaminidase (NAG), g-glutamly transferase (GGT), alkaline phosphates (ALP) activities and their creatinine rations, fractional clearences of Ca2+, PO4-, Na+,K+] analysis and ultrasonographic examinations of the kidneys were performed every other day for 15 days. Heamaturia, proteinuria, glucosuria and granular casts in the microscopic examination of urine sediment were first determined on the 8th day of the experiment. BUN, serum CR and PO4- and K+ concentrations were significantly increased on the 3rd, 9th, and 13th days of the experiment, respectively (p<0.01). Significant decreases in serum albumin and Na^+ concentrations were respectively determined on the 7th and 9th days of experiment (p<0.01). The urine TP/CR rate had significantly increased on the 9th day of the experiment (p<0.01). Significant increase in the GGT/CR (p<0.01), NAG/CR (p<0.01) and ALP/CR (p<0.05) rates were respectively observed on the 7th and 13th days of the experiment. Significant increases in the fractional clearences of PO4-, Ca2+, K+ and Na+ were respectively determined on the 7th, 9th and 13th days of the experiment (p<0.01). Characteristic ultrasonographic changes were observed in all dogs after the 8th day of the experiment. The longitudinal and transversal length of both kidneys increased respectively from 5.79±0.18 cm and 3.05±0.15 cm for the left kidney, and 6.09±0.35 cm and 3.28±0.19 cm for the right kidney before the experiment, to 6.84±0.46 cm and 3.93±0.18 cm for the left and 6.34±0.53 cm and 3.99±0.49 cm for the right on the 11th day of the experiment. Hyperechoic cortex (compared to that spleen and liver) with distinguishable normal hypoechoic medullar papilla was determined. There was an enhancement in corticomedullar demarcation No focal or multifocal alterations were observed. On the basis of this study, nephrosonography seems to be a reliable method for detecting diffuse renal alterations (tubular nephrosis) and diagnosing diffuse renopathies in clinical cases.

Keywords: Dog, Kidney damage, Gentamicin rephrotoxicity, Ultrasonographic examination