Search

The automated analysis of changes of white blood cells and their differential has become a high-throughput laboratory investigation done by hematology analyzers. The subsequent step of manual review of a stained blood film by light microscopy by an experienced investigator is laborious and expensive and has insufficient reimbursement. However, this is the decisive step and basis for very expensive specialized diagnostics like cytogenetics and molecular genetics. The strategy for a stepwise diagnostic procedure plays an important role at this stage. A new proposal is presented here. [ABSTRACT FROM AUTHOR]

Exactly 100 years ago, Artur Pappenheim published the final version of his staining procedure for blood smears ('panoptische Universalfärbung für Bluttrockenpräparate'), in which he combined the Jenner stain and the May-Grünwald stain with the Giemsa stain. Since then, this stain has been referred to as Pappenheim stain or May-Grünwald-Giemsa stain. It provides a strong and reliable staining of the details of nuclei and cytoplasms, with prominent depiction of their granules. Pappenheim's stain is used worldwide with various modifications, which lead to inconsistencies in staining results that are not compatible with modern quality standards. There are no reports on quality assurance of hematological stains in the literature. Therefore, the task force Laboratorium of the German Society of Hematology and Oncology publishes this 'Standard Procedure for the Pappenheim-Stain'. This standard stain reliably produces inter-laboratory identical results in all cytological specimens of body fluids as well as tissue. The staining results parallel those published by Pappenheim in words and images. This standard procedure describes pre-analytical aspects, the staining in jars, and has associated quality assurance issues. Using a similar protocol, automated smear preparation and staining machines produce an identical staining result. We did not investigate staining on racks. We report on preliminary colorimetric data of correct and incorrect Pappenheim stains and describe correct staining using visual and colorimetric terms. [ABSTRACT FROM AUTHOR]

In clinical practice, the reticulocyte count is the most useful method to estimate red cell life span and red cell production. However, experience of hematologists as well as surveys have shown that counting of reticulocytes is often neglected in the diagnostic work-up of unclassified anemias, and many physicians have difficulties in interpreting the results. Formerly, this was partly due to the low precision of manual counts. Today, this method is largely replaced by flow cytometry, available in almost all larger systems for automated blood count analysis, at low costs and sufficient analytic precision. Interpretation is supported by calculated parameters such as the Reticulocyte Production Index. Here, the authors discuss the limits of the analytic methods and the problems of interpretation in the context of the laboratory profile and the clinical setting.