Veterinary session

The least examined, even in laboratory request rarely acting parameter in feline is amylase. One of the reasons- even it is an enzyme produced by pancreas-is the non-significant increase of the enzyme level in cases of pancreatitis.

It seems to be more interesting to focus on another characteristic of this enzyme. In 80 per cents of cases the amylase is filtered by kidney, through glomeruli and a small amount is reabsorbed by tubuli, due to its size and nature. Amylase complexes with immunoglobulins and polysaccharides in blood plasma, forming the so called macroamylase. According to their physical properties, these complexes are heavily heterogeneous large molecules, so they are unable to be excreted in the urine and cause intensive enzyme activity in the serum. Macroamylasemia and hyperamylasemia can be distinguished by separation of the macroamylase and amylase. According to the statistics, the main reason of hyperamylasemia in older feline is IRC.

The goal of our study was the corroboration of our hypothesis that the IRC can be detected by measuring the amylase level before the appearance of the clinical symptoms. During our investigation we detected the differentiation in levels of creatinine and amylase of cats of various ages. The first part of our analysis was to process the blood test results of n=929 European shorthair cats that were investigated at Small Animal Clinic of Szent István University Faculty of Veterinary Science between the years of 2004-2011, with the help of numerous statistical methods. We formed four age-groups (junior: 0-2 years, mature: 3-10 years, senior: 11-14 years and geriatric: older than 15 years) in our study. We categorized the levels of creatinine by the IRIS classification of stages of kidney disease (stage 1: <140 µmol/l, stage 2: 140-250 µmol/l, stage 3: 251-440 µmol/l, stage 4: >441 µmol/l). The amylase values were grouped into „normal”, „moderate increased” and „more than doubled” categories. The results have been processed by the following aspects: the partition of amylase and creatinine concentration in different age-groups and the partition of amylase values in different age-groups according to the different stages of the experienced kidney diseases.

In the second part of our work we have examined the excretion of amylase in cases of n=15 healthy (control) European shorthair cats by determining the amylase clearance. During this, we measured serum amylase level, urine amylase level and amylase clearance/creatinine clearance ratio using modified IFCC method.

In summary, on the one hand we have determined the significant correlations between the age-groups and amylase levels, the age-groups and creatinine levels and in most cases the age-groups and amylase-creatinine level, respectively. On the other hand, we defined that the serum amylase value and the amylase clearance/creatinine clearance ratio may contribute to the early detection of IRC.