Brown Eleanor E, Cooke Kirsten L, Castro Rebeca A, Cooper Alexis, Specht Andrew J, Harris Autumn N
Austin Veterinary Emergency and Specialty, Austin, Texas, USA.
Department of Small Animal Clinical Science, University of Florida College of Veterinary Medicine, Gainesville, Florida, USA.
J Vet Intern Med. 2025 May-Jun;39(3):e70142. doi: 10.1111/jvim.70142.
Inadequate ammonia excretion is thought to drive the development of metabolic acidosis in people with CKD and to correlate with worse outcomes.
To determine if urine ammonia-to-creatinine ratio (UACR) correlates with serum creatinine as a renal function marker in healthy cats and cats with CKD and whether UACR is related to the presence of CKD.
The study group comprised 74 healthy and 45 stable IRIS stage 2-4 CKD cats.
Prospective, single-time point study. Serum biochemistry variables were measured. Urinary ammonia and creatinine concentrations were measured and used to calculate UACR. Group comparisons were made using the Mann-Whitney test. Correlation between UACR concentrations and serum renal and electrolyte values used Spearman's correlation test. Relationships between UACR, renal variables, electrolytes, urine specific gravity, age, and body weight were explored with multiple linear regression.
Chronic kidney disease cats (median 4.2; range 0.6-9.2) had lower UACR than healthy cats (median 7.6; range 3.0-23.7; p < 0.01). UACR was inversely correlated with creatinine concentration (p < 0.01, r = -0.545). The relationship between UACR and creatinine persisted after controlling for age, body weight, electrolytes, renal functional variables, and urine-specific gravity.
These findings suggest that ammonia excretion is impaired with declining renal function.
氨排泄不足被认为会促使慢性肾脏病（CKD）患者发生代谢性酸中毒，并与更差的预后相关。
确定在健康猫和患有CKD的猫中，尿氨与肌酐比值（UACR）是否与作为肾功能标志物的血清肌酐相关，以及UACR是否与CKD的存在有关。
研究组包括74只健康猫和45只处于IRIS 2-4期稳定CKD的猫。
前瞻性单时间点研究。测量血清生化变量。测量尿氨和肌酐浓度并用于计算UACR。使用Mann-Whitney检验进行组间比较。使用Spearman相关检验分析UACR浓度与血清肾和电解质值之间的相关性。通过多元线性回归探讨UACR、肾脏变量、电解质、尿比重、年龄和体重之间的关系。
患有慢性肾脏病的猫（中位数4.2；范围0.6-9.2）的UACR低于健康猫（中位数7.6；范围3.0-23.7；p <0.01）。UACR与肌酐浓度呈负相关（p <0.01，r = -0.545）。在控制年龄、体重、电解质、肾功能变量和尿比重后，UACR与肌酐之间的关系仍然存在。
这些发现表明，随着肾功能下降，氨排泄受损。
