Excessive EDTA induces morphologic changes in bone marrow smears that mimic specific features of dysplasia

An observation of a potential metastatic mimic in bone marrow aspirate smears

We present an interesting observation of crushed erythroid precursors in bone marrow aspirate smears mimicking metastatic deposits. These artefactual clusters could be due to anticoagulation with ethylenediaminetetraacetic and also due to shearing forces exerted on the cells during aspiration and smearing. It is important to be aware of this potential mimic as in a given clinical context it can get misdiagnosed as metastasis.

Downregulation of hypoxia-inducible factor-1α contributes to impaired megakaryopoiesis in immune thrombocytopenia

Impaired megakaryocyte maturation and exaggerated platelet destruction play a pivotal role in the pathogenesis of immune thrombocytopenia (ITP). Previous studies have shown that HIF-1α promotes the homing and engraftment of haematopoietic stem cells (HSCs), thereby stimulating HSC differentiation. However, whether HIF-1α plays a role in megakaryocytic maturation and platelet destruction in ITP remains elusive. Using enzyme-linked immunosorbent assays (ELISAs), we demonstrated that there were lower HIF-1α levels in the bone marrow (BM) of ITP patients than in that of healthy donors and patients with chemotherapy-related thrombocytopenia. Subjects with lower megakaryocyte (<100/slide) and platelet (<30 × 109/L) counts exhibited significantly decreased BM HIF-1α levels, compared to those with higher megakaryocyte (≥100/slide) and platelet (≥30 × 109/L) counts. To test whether HIF-1α regulates megakaryopoiesis and platelet production, megakaryocytes derived from mouse BM cells were treated with an HIF-1α activator (IOX-2; 50 µM) or inhibitor (PX-478; 50 µM). PX-478 significantly decreased HIF-1α expression, cell size, and the populations of CD41-positive and high-ploidy cells. Importantly, to evaluate the role of HIF-1α as a potential therapeutic target in ITP, mouse BM cells were incubated with plasma from ITP patients in the presence or absence of IOX-2. IOX-2 significantly attenuated the ITP plasma-induced decrease in cell size as well as the proportions of CD41-positive and high-ploidy cells. In addition, IOX-2 increased the number of megakaryocytes from mouse BM cells treated with ITP plasma. Our findings indicate that decreased HIF-1α may contribute to impaired megakaryopoiesis in ITP, and HIF-1α may provide a potential therapy for ITP patients.

Supplementary Material to this article is available online at www.thrombosis-online.com.

Deciphering Sources of Variability in Clinical Pathology-It's Not Just about the Numbers

Preanalytical variables can have significant impacts on clinical pathology parameters evaluated during the conduct of a nonclinical safety or toxicity study. These preanalytical variables can be controlled by careful attention to factors such as animal dietary status (diet composition, fasted, and fed state), restraint and anesthesia, intercurrent procedures, timing of clinical pathology collections, and proficiency of animal technicians. The impact of preanalytical variables on test results can be significant enough to result in difficult interpretations and/or regulatory questions or can obfuscate the effects of a test article. Control of preanalytical variables starts with knowledge of what processes and procedures impact test results. Minimizing these effects improves the quality of results and maximizes the value of the study.