Informativeness of clinical and laboratory tests for the diagnosis of chronic renal failure in small animals

Abstract

The study of the clinical and functional state of the kidneys revealed some aspects of the etiology, pathogenesis and diagnosis of chronic renal failure in dogs and cats. The course of the disease in animals at the beginning of the pathology was characterized by polyuria and polydipsia, then – oliguria and anuria, apathy, cachexia, dehydration, ulcers on the gums, salivation, bad breath, dull hair, debilitating vomiting (50% of cases), constipation or diarrhea. Sick animals were diagnosed with tachycardia with increased pulsation of the internal femoral artery and blood pressure from 150/100 to 180/100 mm Hg. art., signs of uremic pneumonia and pulmonary edema. Clinical and laboratory studies have shown that oliguria and anuria in 15 % of studied animals are accompanied by hypothermia up to 35.8 °C, pain in the kidneys, nephromegaly. In the study of urine and blood of animals with CRF, iso- and hypostenuria, proteinuria – in 85 %, glucosuria – in 15 %, hematuria – in 20 %, normochromic anemia. It has been found that the determination of microalbumins in urine is more informative than the determination of proteins, because their appearance precedes the appearance of protein in the urine, which can be considered a diagnostic test for this pathology. It has been proven that in chronic renal failure in dogs and cats develops a pronounced uremic syndrome, accompanied by clinical signs of intoxication – vomiting and hyperazotemia due to increased serum creatinine (up to 574.7 ± 62.5 μmol/l) and urea (37.8 ± 7.94 mmol/l), indicating the development of severe destructive processes in the kidneys. The terminal stages of renal failure are characterized by severe circulatory disorders with myocardial dysfunction and hypertension, progressive anemia. We associate the development of arterial hypertension with the formation of vasoconstrictor – angiotensin II, which can affect the systemic circulation through the defeat of the glomeruli of the renal corpuscles and proximal tubules. Suppression of erythropoietin production results in anemia, which we also associate with hematuria and bone marrow suppression by nitrogen-containing blood compounds.