Nontraditional applications in clinical pathology.

Most published reviews of preclinical toxicological clinical pathology focus on the fundamental aspects of hematology, clinical chemistry, coagulation, and urinalysis in routine toxicology animal species, for example, rats, mice, dogs, and nonhuman primates. The objective of this continuing education course was to present and discuss contemporary examples of nonroutine applications of clinical pathology endpoints used in the drug development setting. Area experts discussed bone turnover markers of laboratory animal species, clinical pathology of pregnant and growing laboratory animals, clinical pathology of nonroutine laboratory animal species, and unique applications of the Siemens Advia(®) hematology analyzer.

Enumeration of nucleated red blood cells with the ADVIA 2120 Hematology System: an International Multicenter Clinical Trial.

The accurate, reproducible, and timely reporting of nucleated red blood cells (NRBC) is an important function of the clinical hematology laboratory. We used 960 samples from 5 worldwide sites to evaluate a new NRBC enumeration method for the ADVIA 2120 Hematology System. The method showed excellent correlation with microscopy (r = 0.

Prognostic relevance of large-platelet counts in patients with immune thrombocytopenic purpura.

In this preliminary study, the value of different platelet parameters, measured by the ADVIA120 Analyzer, in predicting the immediate response to intravenous immunoglobulin or intravenous anti-RhoD was assessed in 31 patients with immune thrombocytopenic purpura. The number of large platelets pre-treatment was the only independent predictor of the 24 hour-platelet increase.

A rapid, automated flow cytometric method to measure activated degranulated platelets by density determination.

Platelet activation is reported to correlate with acute coronary syndromes. A platelet analysis method on the ADVIA 120 Hematology System provides rapid analysis of platelet density, reported as mean platelet component (MPC) concentration, utilizes routine hematology specimens, requires no pre-treatment, and thirty seconds to generate results. Sub-populations of platelets separated by density gradients showed excellent correlation with the ADVIA 120 MPC parameter (r = 0.

Automated analysis of feline platelets in whole blood, including platelet count, mean platelet volume, and activation state.

A new whole-blood flow cytometric method has been developed for counting and sizing platelets in samples from cats, a species in which platelet and red blood cell sizes overlap significantly. The method is a modified version of the two-angle laser light scattering technology used by Bayer H*System hematology analyzers. The new method provided accurate platelet counts and mean platelet volumes (MPV, fl) for cats.

Evaluation of the anticoagulants EDTA and citrate, theophylline, adenosine, and dipyridamole (CTAD) for assessing platelet activation on the ADVIA 120 hematology system.

Background: Monitoring of platelet activation by the ADVIA 120 Hematology System requires an anticoagulant and protocol that ensures that platelets are sphered and their activation status is not altered artifactually in vitro.

Methods: Blood from healthy controls was collected into tripotassium EDTA; citrate, theophylline, adenosine, and dipyridamole (CTAD); or a combination of both (E/C) and stored at ambient temperature or at 4 degrees C (E/C only) and then analyzed between 0 and 180 min later on the ADVIA 120. In addition, immunofluorescent flow cytometry was used to identify activated platelets and platelet-leukocyte aggregates.

Automated quantitation of hemoglobin-based blood substitutes in whole blood samples.

It is necessary to develop methods for accurate monitoring of cell-free hemoglobin in circulation. Routine monitoring of circulating cell-free hemoglobin will be useful for evaluating the efficacy of blood substitute administration andfor determining the clearance rates of the blood substitute from circulation. In addition, discriminating between cell-free hemoglobin and cell-associated hemoglobin will enable accurate determination of RBC indices, mean cell hemoglobin and mean corpuscular hemoglobin concentration, in individuals receiving hemoglobin-based blood substitutes.

Improved platelet counting using two-dimensional laser light scatter.

Clinical management of platelet disorders depends on accurate platelet counts. We evaluated a new analytic approach for platelet counting based on improved platelet discrimination. Current automated counting methods provide accurate platelet counts for most samples but often are unable to discriminate platelets accurately from nonplatelet particles such as microcytic RBCs, RBC fragments, and cellular debris that may falsely elevate platelet counts.

Use of mean platelet component to measure platelet activation on the ADVIA 120 haematology system.

Platelet activation results in changes in a number of cell surface molecules including an increase in P-Selectin (CD62P) that may be rapidly and conveniently measured by immunofluorescent flow cytometry. The ADVIA 120 (Bayer) is a new system that facilitates more accurate measurement of platelet volume and in addition provides an approximate measure of the mean refractive index (RI) of the platelets reported as mean platelet component (MPC) concentration. We were interested to determine whether changes in MPC might reflect changes in platelet activation status.

Reticulocyte hemoglobin content predicts functional iron deficiency in hemodialysis patients receiving rHuEPO.

Early detection of iron sufficiency at the level of the erythropoietic cell is necessary to optimize management of uremic anemia with recombinant human erythropoietin (rHuEPO). "Absolute" and "functional" iron deficiency are the most important factors causing resistance to administered rHuEPO. Transferrin saturation and serum ferritin measurements have been noted to be insensitive and inaccurate measures to detect functional iron deficiency.

Reticulocyte hemoglobin: an integrated parameter for evaluation of erythropoietic activity.

Traditional reticulocyte counts provide only a partial estimate of the erythropoietic bone marrow activity and do not account for qualitative variations of reticulocyte cellular indexes and hemoglobin content in particular. We have studied a new integrated parameter, reticulocyte hemoglobin (retHb), that quantifies in grams per liter the hemoglobin contained in the circulating reticulocyte compartment and is obtained by multiplying the absolute reticulocyte count and the reticulocyte cell hemoglobin content. In 50 normal control subjects, retHb values were 1.