Volume: 57 Issue: 2
Year: 2026, Page: 217-224, Doi: https://doi.org/10.51966/jvas.2026.57.2.217-224
Received: Sept. 12, 2025 Accepted: Nov. 14, 2025 Published: June 30, 2026
Azotemia in cats, characterised by elevated blood urea nitrogen and serum creatinine due to impaired renal clearance, is classified as prerenal, renal, or postrenal. It is a critical biochemical marker for early renal dysfunction and guides interventions such as fluid resuscitation, electrolyte correction, and urinary decompression. Oxidative stress, resulting from an imbalance between reactive oxygen species (ROS) production and antioxidant defenses, plays a pivotal role in disease progression. The present study aimed to identify the etiology of azotemia and evaluate oxidative status in cats with postrenal azotemia. Cats presented to the University Veterinary Hospital, Kokkalai and Mannuthy, with clinical signs of azotemia were screened, and 50 cats with serum creatinine above 1.6 mg/dL were selected. Among the total cases, 60% were identified to be prerenal in origin and 40% were postrenal. The factors contributed to development of prerenal azotemia were haemoprotozoal diseases, gastrointestinal disorders and associated dehydration. Postrenal azotemia was due to obstructive uropathies. Haemato-biochemical analysis of azotemic cats revealed significant increase in total leucocyte, neutrophil, monocyte, eosinophil, erythrocyte, haemoglobin, creatinine, blood urea nitrogen and phosphorous level in diseased group compared with control. In the oxidative profile assessment, the mean total antioxidant capacity and glutathione peroxidase values were higher in diseased cats compared to controls. Early detection of oxidative imbalance may support timely therapeutic intervention and improved urinary tract management in feline patients.
Keywords: Postrenal azotemia, total antioxidant capacity, glutathione peroxidase
Abdel-Saeed, H., Reem, R. T., & Farag, H. S. (2021). Diagnostic and epidemiological studies on obstructive feline lower urinary tract disease (FLUTD) with special reference to anatomical findings in Egyptian tomcats. Bulgarian Journal of Veterinary Medicine, 24, 383–394.
Acierno, M. J. (2022). Nephrology/urology. In M. E. Peterson & J. Talbot (Eds.), Clinical medicine of the dog and cat (4th ed., pp. 452–503). CRC Press.
Ahmed, A. Y., Aowda, S. A., & Hadwan, M. H. (2021). A validated method to assess glutathione peroxidase enzyme activity. Chemical Papers, 75, 6625–6637.
Behzadian, A., & Khoshvaghti, A. (2022). Evaluation of changes in some enzymatic and non-enzymatic antioxidants in cats with feline panleukopenia. Thai Journal of Veterinary Medicine, 52, 213–216.
Cagnasso, F., Bruno, B., Zanatta, R., Bellino, C., Roncone, S., Borella, F., & Borrelli, A. (2022). A retrospective evaluation of neutrophil-lymphocyte ratio, monocyte-lymphocyte ratio and platelet-lymphocyte ratio in cats with obstructive uropathy. In Proceedings of the 75th Convegno DIVAS UNIMI (p. 410). Lodi, Italy.
Cooper, E., & Scansen, B. A. (2020). Obstructive uropathy. In D. C. Twedt, S. J. Ettinger, E. C. Feldman, & R. J. Nelson (Eds.), Clinical small animal internal medicine (Vol. 2, pp. 1109–1122). Wiley-Blackwell.
Daenen, K., Andries, A., Mekahli, D., Van Schepdael, A., Jouret, F., & Bammens, B. (2019). Oxidative stress in chronic kidney disease. Pediatric Nephrology, 34, 975–991.
Debruyn, P., Paepe, D., Daminet, S., & Duchateau, L. (2012). Ultrasonographic findings in cats with lower urinary tract disease. Journal of Feline Medicine and Surgery, 14, 915–921.
Dounousi, E., Papavasiliou, E., Makedou, A., Ioannou, K., Katopodis, K. P., Tselepis, A., & Tsakiris, D. (2006). Oxidative stress is progressively enhanced with advancing stages of CKD. American Journal of Kidney Diseases, 48, 752–760.
Durak, I., Hicri, M., Kacmaz, M., Buyukkocak, S., Cimen, M. B., & Ozturk, H. S. (1999). Black grape enhances plasma antioxidant potential. Nutrition Research, 19, 973–977.
Eggertsdottir, A. V., Lund, H. S., Krontveit, R., & Sorum, H. (2007). Bacteriuria in cats with feline lower urinary tract disease: A clinical study of 134 cases in Norway. Journal of Feline Medicine and Surgery, 9, 458–465.
Fonseca, A. P. B., do Nascimento Silva, F. A., Borges, T. B., Merlini, N. B., Belettini, S. T., Rodrigues, M. C., & Quessada, A. M. (2022). Lower urinary tract disease in felines: A clinical and laboratory study. Ensaios e Ciência, 26, 383–389.
Freitas, G. C., da Cunha, M. C. M., Marina, G., Gomes, K., Monteiro Carvalho Mori da Cunha, J. P., Togni, M., & Carregaro, A. B. (2012). Acid-base and biochemical stabilization and quality of recovery in male cats with urethral obstruction anesthetized with propofol or a combination of ketamine and diazepam. Canadian Journal of Veterinary Research, 76, 201–208.
Griffin, S. (2020). Feline abdominal ultrasonography: What’s normal? What’s abnormal? Renal pelvis, ureters and urinary bladder. Journal of Feline Medicine and Surgery, 22, 847–865.
Gupta, S., Finelli, R., Agarwal, A., & Henkel, R. (2021). Total antioxidant capacity—Relevance, methods and clinical implications. Andrologia, 53, e13624.
Jerabkova, P., Mattoon, J. S., Darveshi, B. R., & Owen, T. J. (2024). Recurrent lower urinary tract signs in a 4-year-old male castrated domestic longhair cat. Journal of the American Veterinary Medical Association, 262, 1265–1268.
Koyner, J. L., Sher Ali, R., & Murray, P. T. (2008). Antioxidants: Do they have a place in the prevention or therapy of acute kidney injury? Nephron Experimental Nephrology, 109, e109–e117.
Kumar, M. N., Anand, P., & Kumar, A. (2020). Levels of total antioxidant capacity (TAC) and oxidative stress in type 2 diabetes mellitus in Kanpur region. Al Ameen Journal of Medical Sciences, 13(2), 83-87.
Lee, J. A., & Drobatz, K. J. (2003). Characterization of the clinical characteristics, electrolytes, acid-base, and renal parameters in male cats with urethral obstruction. Journal of Veterinary Emergency and Critical Care, 13, 227–233.
Lekcharoensuk, C., Osborne, C. A., & Lulich, J. P. (2001). Epidemiologic study of risk factors for lower urinary tract diseases in cats. Journal of the American Veterinary Medical Association, 218, 1429–1435.
Longstaff, L., Gruffydd-Jones, T. J., Buffington, C. T., Casey, R. A., & Murray, J. K. (2017). Owner-reported lower urinary tract signs in a cohort of young cats. Journal of Feline Medicine and Surgery, 19, 609–618.
Lubos, E., Loscalzo, J., & Handy, D. E. (2011). Glutathione peroxidase-1 in health and disease: From molecular mechanisms to therapeutic opportunities. Antioxidants & Redox Signaling, 15, 1957–1997 https://doi.org/10.1089/ars.2010.3586
Majrashi, M., Fujihashi, A., Almaghrabi, M., Fadan, M., Fahoury, E., Ramesh, S., & Dhanasekaran, M. (2020). Augmented oxidative stress and reduced mitochondrial function in ageing goat testis. Veterinary Medicine and Science, 6, 766–774.
Malik, R., Fawcett, A., Page, S. W., Seavers, A., Campbell, A., Sutton, N., & Bessant, C. (2011). Feline focus. Journal of Feline Medicine and Surgery, 13, 537–540.
Martyniv, Y. V. (2024). Seasonality and age-related propensity of cats to occur bacterial urocystitis. Ukrainian Journal of Veterinary and Agricultural Sciences, 7, 3–7.
Nevins, J. R., Mai, W., & Thomas, E. (2015). Associations between ultrasound and clinical findings in 87 cats with urethral obstruction. Veterinary Radiology & Ultrasound, 56, 439–447.
Nithin, B., Sindhu, O. K., Habeeb, B. P., Umesh, C. G., Unny, N. M., & Sebastian, R. (2023). Evaluation of etiology, risk factors and clinical signs of feline lower urinary tract disease (FLUTD) in Northern Kerala. [Incomplete reference—journal details required].
Peel, M. C., Finlayson, B. L., & McMahon, T. A. (2007). Updated world map of the Köppen–Geiger climate classification. Hydrology & Earth System Sciences, 11, 1633–1644.
Piyarungsri, K., Chuammitri, P., Pringproa, K., Pila, P., Srivorakul, S., Sornpet, B., & Pusoonthornthum, R. (2023). Decreased circulating transforming growth factor-beta (TGF-β) and kidney TGF-β immunoreactivity predict renal disease in cats with naturally occurring chronic kidney disease. Journal of Feline Medicine and Surgery, 25, 1098612X231208937.
Pusoonthornthum, R., Pusoonthornthum, P., & Osborne, C. A. (2012). Risk factors for feline lower urinary tract diseases in Thailand. Thai Journal of Veterinary Medicine, 42, 517–522.
Quintavalla, F., Basini, G., Fidanzio, F., Bussolati, S., Sabetti, M. C., Crosta, M. C., & Ramoni, R. (2024). Blood plasma and urinary biomarkers of oxidative stress in cats with urethral obstruction. BMC Veterinary Research, 20, 163.
Ramadhani, D., Suvifan, V. A., Purnami, S., Rahajeng, N., Lusiyanti, Y., Wanandi, S. I., & Syaifudin, M. (2021). Superoxide dismutase and glutathione peroxidase activities in a population exposed to high indoor radon concentration: A preliminary report. Free Radical Research, 55, 1094–1100.
Rubio, C. P., Martinez-Subiela, S., Hernández-Ruiz, J., Tvarijonaviciute, A., & Ceron, J. J. (2017). Analytical validation of an automated assay for ferric-reducing ability of plasma in dog serum. Journal of Veterinary Diagnostic Investigation, 29, 574–578.
Sharma, S. K., Singh, D., Pandey, H., Jatav, R. B., Singh, V., & Pandey, D. (2022). An overview of roles of enzymatic and nonenzymatic antioxidants in plants. In Antioxidant defense in plants: Molecular basis of regulation (pp. 1–13).
Sparkes, A. H., Caney, S., Chalhoub, S., Elliott, J., Finch, N., Gajanayake, I., & Quimby, J. (2016). ISFM consensus guidelines on the diagnosis and management of feline chronic kidney disease. Journal of Feline Medicine and Surgery, 18, 219–239.
Sugimoto, I., Itagaki, A., Saito, T., & Lee, S. (2023). Responses to oxidative stress and antioxidant capacity in rats at different growth stages. Journal of Physical Therapy Science, 35, 793–795.
Teng, K. T., McGreevy, P. D., Toribio, J. A. L., Raubenheimer, D., Kendall, K., & Dhand, N. K. (2018). Strong associations of nine-point body condition scoring with survival and lifespan in cats. Journal of Feline Medicine and Surgery, 20, 1110–1118.
Williams, K., MacDonald-Dickinson, V., & Matsuyama, A. (2024). The incidence and trends of proteinuria, azotemia and hypertension in cats receiving toceranib phosphate. Journal of Feline Medicine and Surgery, 26, 1098612X241266418.
© 2026 Keerthana et al. This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
Keerthana, P.P., Manju, K. M., Madhavan, Unny. N., Sangeetha, S. Gireesh., Y. Ajith. & S. Anoop. (2026). Aetiological investigation of azotemia and oxidative profiling of postrenal azotemic cats in central Kerala. Journal of Veterinary and Animal Sciences, 57(2),217-224 https://doi.org/10.51966/jvas.2026.57.2.217-224