Triglyceride deposit cardiomyovasculopathy: a rare cardiovascular disorder.

Triglyceride deposit cardiomyovasculopathy (TGCV) is a phenotype primarily reported in patients carrying genetic mutations in PNPLA2 encoding adipose triglyceride lipase (ATGL) which releases long chain fatty acid (LCFA) as a major energy source by the intracellular TG hydrolysis. These patients suffered from intractable heart failure requiring cardiac transplantation. Moreover, we identified TGCV patients without PNPLA2 mutations based on pathological and clinical studies. We provided the diagnostic criteria, in which TGCV with and without PNPLA2 mutations were designated as primary TGCV (P-TGCV) and idiopathic TGCV (I-TGCV), respectively. We hereby report clinical profiles of TGCV patients. Between 2014 and 2018, 7 P-TGCV and 18 I-TGCV Japanese patients have been registered in the International Registry. Patients with I-TGCV, of which etiologies and causes are not known yet, suffered from adult-onset severe heart disease, including heart failure and coronary artery disease, associated with a marked reduction in ATGL activity and myocardial washout rate of LCFA tracer, as similar to those with P-TGCV. The present first registry-based study showed that TGCV is an intractable, at least at the moment, and heterogeneous cardiovascular disorder.

Tissue factor expression on monocytes induced by anti-phospholipid antibodies as a strong risk factor for thromboembolic complications in SLE patients.

Our aim was to clarify the role of anti-phospholipid antibodies in the pathogenesis of monocyte tissue factor (TF) expression and thromboembolic complications (TE) in patients with SLE. We examined cell surface expression of TF on monocytes in 93 SLE patients. Monocyte TF expression was significantly higher in SLE patients who had TE than in other SLE patients, and confirmed that the high expression of monocyte TF was a strong risk factor for TE. Furthermore, the presence of anti-cardiolipin/beta2-glycoprotein I antibodies (anti-CL/beta2-GPI) was strongly associated with the high expression of monocyte TF. We therefore studied the in vitro effect of IgG anti-CL/beta2-GPI on lipopolysaccharide (LPS)-induced expression of TF on monocytes in healthy peripheral blood and found that purified IgG containing anti-CL/beta2-GPI significantly enhanced LPS-induced monocyte TF expression. These results suggest that anti-CL/beta2-GPI cause persistently high TF expression on monocyte, which may contribute to the risk of thromboembolic events in SLE patients.

[Fragmented red cells are the major cause of spuriously high platelet counts in patients with fragmented red cells when counts are obtained by automated blood cell counter].

Platelet counts measured by automated blood cell counter often show spuriously high values when measuring samples contain particles of equal size to platelets. The major cause of spuriously high platelet counts in samples with fragmented red cells (FRC) is thought to be the FRC themselves. We studied the correlation between FRC and spuriously high platelet counts in 40 patients demonstrating FRC on blood smears. FRC were measured by manual hemocytometry and by flow cytometry using a monoclonal antibody against glycophorin A (GPA method). There was a significant correlation between spuriously high platelet counts and FRC by manual hemocytometry (r=0.60, p<0.001) or FRC by the GPA method (r=0.45, p<0.005). These data suggest that FRC are the major cause of spuriously high platelet counts in samples with FRC.

[Usefulness of immunoplatelet measurement using the flow cytometric method for accurate platelet counting in hematological patients with severe thrombocytopenia].

We measured platelet counts in 95 patients with hematological disorders accompanied by thrombocytopenia (platelet counts < 5.0 x 10(4)/microliter) including 35 patients with severe thrombocytopenia(platelet counts < 2.0 x 10(4)/microliter). We used four methods based on different principles and compared the results, i.e., the flow cytometric method (BEADS method) utilizing platelet-specific monoclonal antibody (SZ2, antiGPIb) in conjunction with fluorescent reference beads (Flow-Count Fluorospheres), manual hemocytometry, and two automated blood cell counters, the NE-8000 (impedance method) and the Technicon H-2 (optical method). The BEADS method was superior to the other methods in linearity of serial dilutions, and the coefficient variations of the BEADS method(2.5-5.2%) were superior to the other methods. The platelet counts measured by the automated blood cell counters were higher(0.6-0.9 x 10(4)/microliter) than those by the BEADS method and manual hemocytometry. Furthermore, the BEADS method was able to measure accurate platelet counts in samples containing red blood cell fragments. The BEADS method may be an accurate and useful method for measuring samples with severe thrombocytopenia, and, especially, samples containing red blood cell fragments.