Dynamics of biophysical characteristics of albumin in patients on programmed hemodialysis

Abstract

Background. One of the components of the metabolome that performs multifaceted functions in homeostasis is blood albumin. The albumin molecule has a pronounced hydrophilicity, due to which it plays an important role in maintaining oncotic blood pressure. Thus, the expansion of knowledge about the interrelationships of traditional biochemical information about the concentration of albumin and the biophysical properties of its derivatives complements the idea of the pharmacological effect of albumin transfusions. THE AIM: to study of the biophysical properties of albumin in patients with chronic kidney disease on programmed hemodialysis.Patients and Methods. The study included 29 patients with chronic renal failure treated with programmed bicarbonate hemodialysis for an average of 110 months. To assess the condition of patients, a complex of laboratory studies was used, including hematological examination on Beckman Coulter analyzers; clinical assessment of nutritional status based on data from the analysis of medical histories; assessment of colloidal osmotic blood pressure by calculation, as well as by direct measurement on a BMT 923 oncometer; measurement of particle size in blood plasma by dynamic light scattering on a Photocor Compact spectrometer- Z. Statistical analysis of the material was performed using the Statistica for Windows v.6.0 software package. The null statistical hypothesis of the absence of differences and connections was rejected at p<0.05. RESULTS. The average correlation coefficient of oncotic pressure was 0.94 for total protein and 0.90 for albumin. Measurement of colloidal osmotic pressure showed a significant increase in pressure in each of the postdialysis samples. The hydrodynamic radius of the albumin peak for the predialysis sample is significantly higher, which may indicate a change in the sorption properties of the albumin surface. CONCLUSION. The calculation of oncotic pressure by the concentration of total protein, as a rule, provides clinical needs, however, with a significant concentration of toxins, clinical situations are possible in which a moderate decrease in the concentration of the "total protein" of the blood is detected, hence the main oncotic component – albumin is noted but there is a development pronounced edematous syndrome due to a significant decrease in oncotic pressure as a result of a conformational change in albumin molecules. In such situations, it is necessary to directly determine the oncotic pressure of the blood. Keywords: albumin, oncotic pressure, hydrodynamic radius, dialysis>˂0.05.Results. The average correlation coefficient of oncotic pressure was 0.94 for total protein and 0.90 for albumin. Measurement of colloidal osmotic pressure showed a significant increase in pressure in each of the postdialysis samples. The hydrodynamic radius of the albumin peak for the predialysis sample is significantly higher, which may indicate a change in the sorption properties of the albumin surface.Conclusion. The calculation of oncotic pressure by the concentration of total protein, as a rule, provides clinical needs, however, with a significant concentration of toxins, clinical situations are possible in which a moderate decrease in the concentration of the "total protein" of the blood is detected, hence the main oncotic component – albumin is noted but there is a development pronounced edematous syndrome due to a significant decrease in oncotic pressure as a result of a conformational change in albumin molecules. In such situations, it is necessary to directly determine the oncotic pressure of the blood.