Problem: A 7-year-old domestic short hair cat presents for drinking increased amounts of water and urinating outside of the litter box. The patient has an elevated creatinine of 2.2 mg/dL (ref range: 0.4-0.9 mg/dL) and an elevated urea of 65 mg/dL (ref range: 7-28 mg/dL) with a USG of 1.023.
1.) What organ system is most likely affected?
2.) What is the definition of azotemia?