Pilot study on the use of basophil activation tests and skin tests for the prevention of allergic transfusion reactions

Background and objectives

Management of severe allergic transfusion reactions (ATR) is challenging. In this study, we investigate the usefulness of skin tests and basophil activation tests (BAT) in chronically transfused patients for the prevention of future ATR.

Materials and methods

BAT and skin tests were carried with the supernatant of red blood cell (RBC) units for a sickle-cell disease patient under chronic exchange transfusion who has presented a severe ATR, in order to prevent potential future ATR. If the results for both BAT and skin tests were negative, the RBC units could be transfused to the patient. If either one of the results was positive, the tested RBC unit was discarded for the patient.

Results

192 RBC units were tested with both tests. The level of results concordance between the two tests was 95%. Out of the 169 negative units with both tests, 118 units were transfused to the patient for which he presented no ATR.

Conclusion

In our study, combining both BAT and skin tests was associated with a good negative predictive value since we were able to safely transfuse our patient. Further studies are still necessary to confirm this result but this pilot study indicates that skin tests and BAT might help prevent ATR. When BAT is not available, skin tests may also be useful in preventing ATR.

Differential diagnosis of lymphocytosis in routine laboratory practice: Contribution of lymphocyte parameters using the Sysmex-XN9000 haematology analyzer

INTRODUCTION

This study investigates the potential contribution of structural and dispersion parameters, as well as alarms provided by Sysmex XN9000 haematology analyzer. The objective was to assess the need for a microscopic examination in the context of lymphocytosis. It also aims to contribute in differentiating rapidly lymphoproliferative disorders such as chronic lymphocytic leukaemia (CLL), non-chronic lymphocytic leukaemia (NON-CLL) and non-infectious reactive lymphocytosis (REAC).

METHODS

We prospectively assessed lymphocyte parameters (Ly-X, Ly-Y, Ly-Z, Ly-WX, Ly-WY, Ly-WZ) provided by the Sysmex XN9000 analyzer; they were measured in the white blood cell differential (WDF) channel which also provides alarms via the precursor/pathological cellular channel (WPC). Blood samples from 71 subjects with CLL, NON-CLL lymphoproliferative and REAC non-infectious reactive lymphocytosis, as well as a control (NORM) group of 12 subjects without any abnormalities were analyzed.

RESULTS

The most discriminating parameters to distinguish the different groups were Ly-X, Ly-Z and Ly-WZ. The lymphoid structural parameters Ly-X and Ly-Z significantly discriminated the CLL group from the other groups (p < 0.001), and the CLL group from the REAC group (p < 0.01), respectively. The Ly-WZ parameter discriminated the CLL group from the NON-CLL, REAC (p < 0.001) and NORM (p < 0.01) groups. Alarms were higher in all study groups compared to the NORM group. An algorithm integrating these structural and alarm parameters is proposed.

CONCLUSION

This study demonstrated that Ly-X, Ly-Z, and Ly-WZ lymphocyte parameters are useful for detecting morphological changes in lymphocytes; they provide useful information for the differential diagnosis of lymphocytosis, and this before the examination of the blood smear. An algorithm combining the WDF (parameters) and the WPC (alarms) makes it possible to decide whether or not to use a microscopic examination or flow cytometry immunophenotyping.

Assessment of the Androstenedione Assay on a Roche Analytical Platform and Comparison with Different Methods

BACKGROUND

D4-androstenedione (D4ASD) is an intermediate hormone of androgen biosynthesis by the gonads and the adrenal glands. The interest in D4ASD concentration assessment resides in diagnostics of androgenic hyperproduction pathologies. Currently, many D4ASD quantification methods are available on the market including immunological methods that remain problematic due to the possible cross-reactivity with endogenous or exogenous steroids.

METHODS

Recently Roche® launched a new fully automated instrument for the measurement of D4ASD concentration. In this paper, the criteria of analytical performance (repeatability and intermediate precision) of the D4ASD Roche® assay were assessed and compared with 2 different methods including a radioimmunoassay (RIA) as well as a liquid chromatography tandem mass spectrometry (LC-MS/MS) method.

RESULTS

Repeatability and intermediate precision of the D4ASD Roche® were acceptable according to the prede-fined RICOS standard (CV ≤ 7.9%) and the assay showed a good correlation with other assays considering the 95% CI obtained for the slope and the y-intercept.

CONCLUSIONS

This method demonstrates acceptable criteria of analytical performance with an intermediate imprecision and a trueness within the fixed acceptance limits.