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Multiple Myeloma
Published in Pat Price, Karol Sikora, Treatment of Cancer, 2020
The most common abnormality seen on a full blood count is a normochromic, normocytic anemia, or macrocytic anemia. The blood film often shows rouleaux formation due to the presence of a paraprotein. When circulating plasma cells are seen at a level of over 2 × 109/L, a diagnosis of plasma cell leukemia can be made. The ESR is usually raised in myeloma (except light chain myeloma) as the result of the high serum globulin levels.
Red Cell Aggregation and Yield Stress
Published in Gordon D. O. Lowe, Clinical Blood Rheology, 2019
In spite of the fact that this curious stickiness of erythrocytes has been known for so long, it is only in the past few decades that its causes have been closely studied, and even now its significance to normal and abnormal physiology is not entirely clear. There is, however, no doubt that cellular aggregation is responsible for much of the increasing viscosity observed in whole blood as the shear rate to which it is exposed falls to low levels (Chapter 2, this volume). It also appears to endow blood with a yield stress that must be exceeded before flow can start. Both of these effects can be expected to reduce blood flow, compared to a nonaggregating system. On the other hand, the intercellular forces that lead to aggregation probably assist the axial streaming of red cells which is thought to enhance flow in smaller vessels; but in so doing, the other cellular components, the white cells and platelets, tend to be excluded from the central region of flow, thereby increasing their interaction with the walls of blood vessels. A further important aspect is that all of these effects are highly sensitive to the plasma composition, since rouleaux formation is strongly influenced by the prevailing concentration of fibrinogen and, though to a lesser extent, that of other plasma proteins. It is, therefore, thought to be an important factor in any description of the in vivo circulation.
Red Blood Cell and Platelet Mechanics
Published in Michel R. Labrosse, Cardiovascular Mechanics, 2018
The formation of rouleaux is physiologically relevant, as it strongly affects blood viscosity at low shear rates. If an RBC suspension containing rouleaux is driven through a blood vessel or microchannel at low flow speeds, the rouleaux are strong enough to withstand shearing forces and thus remain largely intact. Consequently, their relatively large size hinders blood flow, which manifests itself in a large macroscopic flow resistance and eventually in large values of the apparent viscosity. If shear rates are increased, the rouleaux gradually start to break apart, leading to a suspension containing more and more isolated RBCs. These individual cells can more easily slide past each other than the large rouleaux. Consequently, the flow resistance is lower and the apparent viscosity of blood diminishes on increasing the shear rate. In the language of non-Newtonian rheology, such behavior is termed shear thinning. By using appropriate phenomenological aggregation models, computer simulations are able to reproduce the effect of rouleaux breakup and shear thinning fairly well (Fedosov et al. 2011).
Forward and reverse typing discrepancy and crossmatch incompatibility of ABO blood groups: cause analysis and treatment
Published in Hematology, 2023
Hongmei Qiu, Xuechun Wang, Yan Shao
MM, a malignant plasma cell dyscrasia, produces a considerable quantity of aberrant immunoglobulins, the M-protein. Significant amounts of M-protein can invert the ratio of plasma albumin to globulin [6]. An excessive increase in plasma globulin and plasma globulin-coated red blood cells decreases negative charges on the surface of red blood cells and repulsion between blood cells, ultimately leading to aberrant rouleaux agglutination of red blood cells [7]. Herein we provide two treatment options. Option 1: Isotonic saline dilution. Add 1 drop of saline onto a glass slide; the abnormal rouleaux agglutination of red blood cells disappears instantly [8]. Option 2: Saline replacement. Replace the clear plasma supernatant liquid for reverse blood group typing with 100 μl normal saline and resuspend it. The agglutination disappears instantly [9].
Evaluation of the ESR fast detector and Improve® ESR analyzer as modified Westergren methods for erythrocyte sedimentation rate
Published in Scandinavian Journal of Clinical and Laboratory Investigation, 2022
Sirinart Chomean, Areenuch Thamwarokun, Sumittra Jitsuvantaya, Jirapat Attapong, Chollanot Kaset
To overcome the practical drawbacks of the reference method, many novel alternates and modified Westergren methods have been developed for the ESR measurement. Alternate ESR methods measure the initial stage of rouleaux formation of RBC by various principles such as centrifugation or photometric aggregometry [9,10]. These methods reduced the analysis time and are operated in close systems to improve operator safety. However, inconsistency of results has been reported in patients with various disorders [9]. The results may be caused by the measuring principle that differs from the reference method [9]. Several studies proposed the modified Westergren method, which demonstrated improved precision and excellent correlation than the reference method [7–9]. Automated Ves-Matic (Diesse Diagnostica Senese S.p.A., Italy), Vacuette® SRS (Greiner Bio-One, Austria) method and Monitor 100® (Electa Lab, Italy), a modified Westergren method, showed a reliable and suitable system for safe performance saving the analysis time [6–8,12]. There are many advantages of the automated modified Westergren method, including high-throughput sample testing, undiluted EDTA blood, single sample for both ESR and other hematologic tests, enhancing patients and personnel safety, reducing workload, and shortening the turnaround time [6].
Enrichment of plasma in platelets and extracellular vesicles by the counterflow to erythrocyte settling
Published in Platelets, 2022
Darja Božič, Domen Vozel, Matej Hočevar, Marko Jeran, Zala Jan, Manca Pajnič, Ljubiša Pađen, Aleš Iglič, Saba Battelino, Veronika Kralj-Iglič
We have observed that temperature had considerable effect on concentration of P3 particles in EPP (Figure 3C, D). Lower temperature induces an increase of viscosity of the medium (which decreases velocities of all particles), platelet branching [25] and affects erythrocyte association in rouleaux. If blood is diluted, ESR is reduced despite lower viscosity of the suspension, mainly because the direct interactions between erythrocytes are hindered [26,27]. Furthermore, previous studies have shown that platelet activation at room temperature does not trigger the release of α-granules [26] meaning that such treatment does not cause premature release of growth factors. Concomitantly, platelet activation induces serotonin uptake from plasma and its storage in dense granules [25], which may contribute to the regenerative effects of PVRP [28].