Description of unilateral kidney embolism and contralateral nephrectomy as a less invasive remnant kidney model in cats; a proof-of-concept study

Background

Refined models of kidney disease are critical to better understand disease processes and study novel treatments while minimizing discomfort in research animals. The objective of this study was to report a technique for minimally invasive partial kidney embolism in cats and describe outcomes following transcatheter administration of embolic microspheres with subsequent contralateral nephrectomy.

Methods

Eleven, apparently healthy, male, purpose-bred cats underwent unilateral kidney embolism with 0.25 or 0.5 mL of embolic microparticle (40–120 μm) suspension (0.2 mL microspheres/mL) delivered into the right renal artery under fluoroscopic guidance, followed 5 months later by contralateral nephrectomy. One month after nephrectomy, blood and urinary markers of kidney function were evaluated, and embolized kidneys were harvested for histopathology evaluation.

Results

Renal artery embolization was possible in all cats. Two cats did not complete the study, one after experiencing congestive heart failure (n = 1) and the other following evidence of complete kidney embolism precluding nephrectomy (n = 1) post-embolization. At study end, compared to baseline, cats had significant increases in median (range) serum creatinine (159.1 μmol/L [141.4–530.4] versus 128.2 μmol/L [92.8–150.3]; p = 0.0004), urea nitrogen (15.71 mmol/L [9.29–47.85] versus 7.50 mmol/L [6.07–8.57]; p < 0.0001), and symmetric dimethylarginine (0.74 μmol/L [0.59–3.12] versus 0.67 μmol/L [0.54–0.72]; p = 0.0288) concentrations. No differences in markers of kidney function were documented between dose groups.

Conclusions

Minimally invasive kidney embolism is a promising technique for modeling kidney disease in cats. Understanding optimal dose, timing of nephrectomy, and longer-term consequences requires additional work.