Serum cystatin C in renal transplant patients.

Assessment of renal function in clinical medicine is of great importance especially in patients with renal transplants. Cystatin C has the characteristics of an ideal marker to assess renal glomerular filtration rate. Forty patients with renal transplants under steady-state post-transplant conditions were included in the study. Steady-state was defined as lack of acute rejection periods during the last 6 months and stable cyclosporin A medication during the past 4 weeks. Gender was balanced with 20 male and 20 female patients, the mean age was 51+/-14 years, time since transplantation was 5+/-3.5 years. Fifteen percent of the patients suffered from diabetes mellitus. Immunosuppression consisted of cyclosporin A, imuran, and prednisolon. To assess renal function cystatin C, creatinine clearance, serum creatinine, and serum beta2-microglobulin were tested. Creatinine was analysed in serum and urine to calculate the creatinine clearance related to 1.73 m(2) body surface. Cystatin C and beta2-microglobulin were determined by using a particle-enhanced turbidimetric assay. Cystatin C correlated best with creatinine clearance (r=0.66), beta2-microglobulin (0.57), and serum creatinine (0.56). The diagnostic accuracy of cystatin C was significantly better than serum creatinine (p<0.05), but did not differ significantly from creatinine clearance (p=0.73), and beta2-microglobulin (p=0.46). Our data show that patients with renal transplants, cystatin C has a similar diagnostic value as creatinine clearance. However, it is superior to serum determination of creatinine and beta2-microglobulin. Cystatin C allows for rapid and accurate assessment of renal function in patients with renal transplants and is clearly superior to the commonly used serum creatinine.

[Oligoclonal immunoglobulins in the blood serum and monoclonal light chains in the urine in malignant diseases of myelopoiesis]. / Oligoklonalni imunoglobulini v kruvniia serum i monoklonalni leki verigi v urinata pri niakoi zlokachestveni zaboliavaniia na mielopoezata.

The serum of 21 patients with acute leukemia, 9 patients with chronic myeloid leukemia and 30 clinically healthy controls were examined by isoelectric focusing. The urines of 12 patients were examined by immune isofocusing. Oligoclonal bands were found in the serum of 9 patients. In the urine of 4 patients secretion of monoclonal light chains were found. In comparison with the routinely applied methods electrophoresis and immunoelectrophoresis the isoelectric focusing and the immune isofocusing gave additional information about the immunoglobulins and their light chains in 11 of 30 patients (36.7%).

[Renal proteinuria studied by isoelectric focusing]. / Izsledvane na bubrechni proteinurii chrez izoelektrichno fokusirane.

The urines of 33 patients with various renal diseases and proteinuria from 0.5 up to 4.7 g/l were examined by isoelectric focusing in flat polyacrylamide gel with pH range of 3.5-10. According to the type of the individual proteins excreted in the urine, identified by immunoelectrophoresis, the following types of proteinuria were differentiated: physiological--4 patients, moderately selective--26 patients, and feebly selective--3 patients. The isoelectric focusing of the urine revealed that the urine proteins were distributed in pH range 3.5-6.3. The lower the proteinuria, selectivity--the more proteins are found by isofocusing and the more they engage the cathode part of the pH-gradient. 22 urines can be examined simultaneously. The isofocusing allows the differentiation of the proteinuria and yields results well comparable with those of the immunoelectrophoresis.

[Information value of isoelectric focusing of serum proteins in non-Hodgkin's lymphomas]. / Informativna stoinost na izoelektrichnoto fokusirane na serumnite beltutsi pri nekhodzhkinovi limfomi.

The importance of isoelectric focusing of serum proteins was studied in 35 patients with non-Hodgkin lymphoma: multiple myeloma--10 patients, chronic lymphatic leukemia--5 patients, other non-Hodgkin malignant lymphoma--20 patients. 30 clinically healthy persons were also examined as controls. By isoelectric focusing the images with monoclonal immunoglobulins differ from those with polyclonal immunoglobulins. Using this method paraproteinemia was found in 19 patients (54%): in all patients with multiple myeloma 2 patients with chronic lymphatic leukemia and 3 patients with other non-Hodgkin malignant lymphoma. By electrophoresis on cellulose acetate folia paraprotein was found in 13 patients only. In the remaining patients, in whom monoclonal immunoglobulin was found only by isoelectric focusing, the electrophoresis, total serum protein, IgA and IgM did not show pathologic deviations. The IgG values were normal or borderline. The isoelectric focusing exceeds the other methods in informative value. Further study is necessary in order to confirm the diagnostic and prognostic value of isoelectric focusing in non-Hodgkin malignant lymphoma.