Socks, an 11-year-old, 5.8-kg, castrated domestic shorthaired cat was presented for evaluation of suspected chronic kidney disease (CKD).

Clinical PresentationSocks appeared bright, alert, and responsive. He had a body condition score (BCS) of 2.5 out of 5, rectal temperature of 101.6°F, heart rate of 200 beats/min with strong regular pulses, and respiratory rate of 48 breaths/min. The hydration status was adequate. No abnormalities were detected on thoracic auscultation, but palpation revealed small, firm, irregular kidneys.

No enlargement of the thyroid glands was noted, and there were no abnormalities on funduscopic examination. The systolic blood pressure by indirect Doppler measurement was 135 mm Hg (normal, <160).

Laboratory FindingsLaboratory studies of blood, serum, and urine were conducted; the urine protein:creatinine ratio and blood urea nitrogen (BUN) and creatinine concentrations remained unchanged (Table 1, below) from laboratory studies obtained 2 weeks earlier.

Urinalysis was performed on a urine sample obtained by cystocentesis; culture was negative.