Acute tubular necrosis (ATN) was described in canine babesiosis. Hypotension is considered as one of the factors which influence the development of hypoxic renal damage. In this study hypotension defined as mean arterial pressure (MAP) < 80 mmHg was detected in 7 out of 48 dogs (14.6%) infected with Babesia canis. Lower systolic arterial pressure (SAP), diastolic arterial pressure (DAP) and MAP were detected in azotaemic dogs infected with B. canis. Statistically significant negative correlations between blood pressures (SAP, DAP and MAP) and serum creatinine and urea concentrations showed the influence of decreased blood pressure on the development of azotaemia and is probably also associated with ATN in canine babesiosis.
The increase of the serum urea to creatinine ratio (UCR) was observed in dogs infected with Babesia canis. Previous studies have suggested that decrease of blood pressure can be one of the reasons for this phenomenon. In this work statistically significant increase of the UCR was observed in dogs with babesiosis. Comparison of the UCR between 23 azotaemic dogs and 25 non-azotaemic dogs infected with Babesia canis showed statistically significantly higher mean of the UCR in azotaemic dogs. Correlations between UCR and systolic, diastolic and mean arterial pressure (SAP, DAP and MAP) in 48 dogs infected with B. canis were negative (UCR and SAP: r = −0.3909; UCR and DAP: r = −0.3182; UCR and MAP: r = −0.3682) and statistically significant (p < 0.05). This result may indicate contribution of hypotension in the increase of the UCR in canine babesiosis. However, the correlations were not high, and there was no statistically significant correlation between UCR and arterial pressures in azotaemic dogs. Thus, it seems that decrease of blood pressure in dogs with babesiosis explains only partially the cause of increased UCR in infected dogs. The other authors suggested hyperureagenesis and myocardial injury as a potential reason for the increased UCR in canine babesiosis. Thus, further studies are needed to determine causes of increased UCR in dogs with babesiosis, especially on the connection between UCR changes and the concentrations of plasma cardiac troponins and ammonia, and the occurrence of occult blood on fecal examination.