Alpha-1-Fetoprotein (AFP): international proficiency study with different test systems.

BACKGROUND: The present proficiency study aimed to elucidate the comparability and reliability of test systems for the determination of AFP concentrations. METHODS: 25 laboratories using 8 different commercial test systems used liquid BIOREF-AFP control serum in their routine internal quality control over a period of one year. For statistical analysis the results were collected centrally. RESULTS: The statistical analysis of the test results revealed considerable variation for the different laboratories. The deviations of the mean values of different laboratories from the overall mean value varied between 0.1 and 26.1%, and for most of the laboratories the deviation was round about 10%. The precision of measured values in the individual laboratories was in most cases acceptable: Nevertheless, the coefficients of variation of the individual laboratories ranged from 13 to 16.1%. CONCLUSIONS: In conclusion, this study indicates that AFP results vary between different laboratories albeit an international standard for AFP is available. Therefore, every laboratory should participate in external ring studies and should use a quality control serum independent of the test kit manufacturer for the internal quality control.

Multicentre evaluation of performance of C-reactive protein analysis over a one-year period.

This communication deals with a longitudinal evaluation of C-reactive protein (CRP) analysis during a one-year period using a single lot of liquid control sera (3 levels) (BIOREF-CRP levels 1, 2 and 3) in different laboratories. A total of 652 sets of data were returned from 20 participating laboratories using 13 different reagent-measuring device combinations. The use of the control materials was defined in a standard operating procedure. Data was returned to the organizers on a monthly basis and questions could be asked or problems presented during the evaluation period. Although the performance of different reagents varied, the control materials were shown to be stable over the whole of the evaluation period when stored at 4-7 degrees C in a refrigerator/cold room. Typical problems were encountered, examples of which are presented here in graphical and tabular form.

[Elimination of saccharose from the blood and its renal excretion following transfusion of buffy coat-free erythrocyte concentrates containing disaccharides]. / Zur Eliminierung von Saccharose aus dem Blut und ihrer renalen Ausscheidung nach Transfusion buffy coat-freier, disaccharidhaltiger Erythrozytenkonzentrate.

The elimination of sucrose from the blood and its renal excretion was analysed in 108 patients after applying a total of 394 transfusion units (TE), resuspended, buffy-coat-free erythrocyte concentrates (EK) containing 23 mmol of sucrose per TE. In transfusing 3 TE even 90% of the sucrose were eliminated from the blood during the application time and up to 99% within 3 h, nearly 80% were excreted through the kidneys within 12 h. Elimination and excretion were delayed with impaired kidney function. With respect to intravasal elimination of sucrose bilaterally nephrectomized patients have to rely on hemodialysis. Side-effects of sucrose due to extended intravasal and interstitial duration could not be observed in those patients affected with decreased kidney efficiency and after massive transfusions.