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.

Lipopolysaccharide-binding protein as a new and reliable infection marker after kidney transplantation.

The early and reliable differentiation of rejections, viral infections and bacterial infections is one of the main problems after organ transplantation. One promising solution to this problem is the lipopolysaccharide-binding protein (LBP), which is regulated upwards in gram-negative sepsis and related conditions. Therefore, the aim of our study was to explore the diagnostic potential of LBP serum levels in well-defined, non-infectious and infectious events after kidney transplantation (KTx). In a retrospective study the LBP serum levels were measured in a total of 686 serum samples from 52 kidney graft recipients. In all pre-KTx sera tested, the mean LBP level was 8.8+/-3.5 microg/ml (reference range: 2.0-15.2 microg/ml). In 7 of 52 recipients without intraoperative T-cell depletion, the mean LBP level was significantly ( P<0.01) increased (13.0+/-1.5 microg/ml) at post-KTx day 1, but was within the reference range. In contrast, the intraoperative T-cell depletion by antilymphocyte antibodies resulted in a significant ( P<0.01) increase to 25.8+/-11.4 microg/ml (range: 13.3-47.2 microg/ml). In recipients with immediate ( n=14) or delayed ( n=9) graft function without any other complications, all post-KTx values (except the post-KTx peak) were within the reference range. In 10 recipients with steroid-sensitive rejections and in 11 recipients with steroid-resistant rejections, no rejection-associated changes of the LBP levels could be shown. In six recipients with cytomegalovirus infection, the detection of an antigenemia (pp65) also was not associated with alterations of the LBP levels. In addition, there was no correlation between LBP levels and the number of pp65-positive leukocytes in peripheral blood. In contrast, a strong elevation of LBP levels was seen in five recipients with gram-positive bacteremia as well as in other severe bacterial infections (e.g., purulent extravasate, heavily infected grafts, bacterial pneumonia and contaminated hematoma). In two recipients with superinfected (bacterial and mycotic or viral) Pneumocystis carinii pneumonias requiring assisted ventilation, LBP levels were elevated, too. Thus, in our study only systemic non-viral infections and massive lymphocytolysis were associated with elevated LBP serum levels.