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Alloantibodies against platelets can be detected by using different laboratory tests. Most of these tests, which use panel cells or antigens as a target, perform poorly in non-selected haematological patients. In relation to these tests, a crossmatch test of transfused platelets and patient's serum may be viewed as the standard and may be superior in predicting donor platelet destruction by alloimmunization.In 95 randomly selected thrombocytopenic patients with haematological malignancies, who were receiving leucodepleted blood products, 184 serum samples were studied in anin vitrocrossmatch test by using the technique of the platelet immunofluorescence test (crossmatch-PIFT), in anin vivocrossmatch test detectingin vivobinding of immunoglobulins to transfused platelets according to the PIFT technique (in vivo-PIFT), in the indirect PIFT using five random donors as a target (panel-PIFT) and in an enzyme linked immunosorbent assay using immobilized human leucocyte antigens (HLAs) of 100 standardized donors (ELIHLA). The results of all these methods were related to the recovery at 1 and 16 h post-transfusion.The results of the crossmatch-PIFT were not associated with platelet recovery at 1 and 16 h after transfusion. Even in a subgroup of patients, in whom predefined clinical factors were excluded, no association with platelet recovery was found. The results of the crossmatch-PIFT correlated with those of thein vivo-PIFT (P = 0·02); however, 35 (19%) discrepant results were identified between these tests. The results of the crossmatch-PIFT were not related to the panel-PIFT (P = 0·25), but did relate to those of the ELIHLA (P = 0·02), still revealing 36 (20%) discrepant results. None of thein vivo-PIFT, the panel-PIFT or the ELIHLA was associated with platelet recovery after 1 h, whilst only a positive panel-PIFT was associated with poor platelet recovery at 16 h after transfusion (P = 0·03).In a population at low risk for alloimmunization, the correlation of test outcome and platelet recovery is poor. None of these crossmatch tests or screening tests was identified as superior to any other in this population. [ABSTRACT FROM AUTHOR]

Alloantibodies against HLA antigens can be reduced by applying leukodepletion to transfusions. Because the importance of immunological and nonimmunological causes of poor platelet transfusion results using leukodepleted transfusions is not clear, we conducted a prospective study in an unselected patient population receiving leukodepleted transfusions. In 97 patients with hematological malignancies, 181 random leukodepleted platelet transfusions were studied for immunological causes of poor platelet transfusion results by calculating the odds ratio of four different screening tests for a low platelet recovery. Nonimmune causes were also studied by calculating the odds ratio of the most prevalent nonimmune causes for a low platelet recovery. No single screening test showed an association with recovery after 1 and 16 h following a platelet transfusion. The combination of a positive enzyme-linked immunosorbent assay (ELISA) and platelet immunofluorescence test (PIFT) or a combination of a positive lymphocyte immunofluorescence test (LIFT) and PIFT, demonstrating an association with a low platelet recovery after 16 h, was present in 2% of all platelet transfusions. Of nonimmune causes, splenomegaly and storage time of platelets for more than 3 days were associated with low platelet recovery after 1 h and 16 h of being present in 29% and 47% of all platelet transfusions, respectively. Immunological causes account for a small proportion of poor platelet transfusion results compared to nonimmunological causes in a nonselected patient population receiving leukodepleted transfusions. [ABSTRACT FROM AUTHOR]

We describe congestive heart failure caused by autoimmune myocarditis in a patient with primary Sjögren's syndrome. Only after corticosteroids were given did the symptoms and laboratory abnormalities disappear. [ABSTRACT FROM AUTHOR]

Abstract: Introduction: Evaluation of red blood cell (RBC) morphology is an important first step in the differential diagnosis of hereditary hemolytic anemia. It is, however, labor intensive, expensive, and prone to subjectivity. To improve and standardize the analysis of RBC morphology as a screening tool in the diagnosis of hereditary hemolytic anemia, we studied its automated analysis by digital microscopy (DM). Methods: Blood from 90 patients with hereditary hemolytic anemia and 32 normal control subjects was analyzed by the CellaVision DM96 Digital Microscope. Results: All hemolytic RBC abnormalities could be distinguished by the presence of at least one aberrant red cell type. In particular, the percentage of microcytes was highly sensitive and specific (AUCROC = 0.97) for RBC membrane disorders, and a cut‐off of 5.7% microcytes was calculated to be optimal to distinguish patients from healthy controls. Subgroup analysis of patients with RBC membrane disorders revealed additional distinct differences according to the underlying gene defect. A number of cell types were significantly elevated in sickle cell anemia patients, such as polychromatic cells, macrocytes, and poikilocytes. The increase in helmet cells (AUCROC = 0.96) and hypochromic cells (AUCROC = 0.91) was specific for β‐thalassemia, whereas patients with pyruvate kinase deficiency showed a significant increased polychromatic cells, macrocytes, and ovalocytes. Patients with hereditary xerocytosis showed significantly higher numbers of polychromatic cells, macrocytes, and target cells. Conclusion: DM holds a promise as a useful screening tool in the diagnosis of hereditary hemolytic anemia by detecting and quantifying distinct morphological changes in RBCs in patients with various forms of hereditary hemolytic anemia. [ABSTRACT FROM AUTHOR]

A letter to the editor is presented which discusses the study on the performance evaluation of digital microscope system in examing peripheral blood smears.

Background: To study etiologies of anemia using an extensive laboratory analysis in general practices. Method: An extensive laboratory analysis was performed in blood of newly diagnosed anemia patients aged ≥50 years from the general population in the city of Dordrecht area, the Netherlands. Eight laboratory-orientated etiologies of anemia were defined. Patients were assigned one or more of these etiologies on the basis of their test results. Results: Blood of 4152 patients (median age 75 years; 49% male) was analyzed. The anemia etiology was unclear in 20%; a single etiology was established in 59%; and multiple etiologies in 22% of the patients. The most common etiologies were anemia of chronic disease (ACD) (54.5%), iron deficiency anemia (IDA) (19.1%) and renal anemia (13.8%). The most common single etiologies were IDA (82%) and ACD (68%), while the multiple etiologies most commonly included folic acid deficiency (94%) and suspected bone marrow disease (88%). Older age was associated with a lower incidence of IDA and a higher incidence of renal anemia. Mild anemia was more often associated with ACD and uncertain anemia, while severe anemia was mainly seen in patients with IDA. Conclusion: Extensive laboratory analysis in anemic patients from the general population helped clarify the etiology of anemia and revealed many various combinations of etiologies in a significant proportion of patients. Age, sex and the severity of anemia are predictive of the underlying etiology. [ABSTRACT FROM AUTHOR]