scholarly journals Polycythemia vera-associated acquired von Willebrand syndrome despite near-normal platelet count

2010 ◽  
Vol 85 (7) ◽  
pp. 545-545 ◽  
Author(s):  
Ayalew Tefferi ◽  
Kristi J. Smock ◽  
Ajit B. Divgi
Blood ◽  
2016 ◽  
Vol 128 (22) ◽  
pp. 5466-5466
Author(s):  
Amihai Rottenstreich ◽  
Geffen Kleinstern ◽  
Svetlana Krichevsky ◽  
David Varon ◽  
David Lavie ◽  
...  

Abstract Objective: We characterized acquired von Willebrand syndrome (AVWS) among essential thrombocythemia (ET) and polycythemia vera (PV) patients. Methods: A review of patients with ET or PV evaluated for AVWS. Results: Of 116 patients with ET, 64 (55%) developed AVWS; of 57 with PV, 28 (49%) developed AVWS. Median platelet counts of ET and PV patients who developed AVWS were 920 X 109/L and 679 X 109/L, respectively (P=0.01). Of patients who developed AVWS, 69.5% had platelet counts below 1000 X 109/L. Bleeding was more common in patients with AVWS, among both ET and PV patients (P<0.001). VWF:RCo levels and VWF:RCo/VWF:Ag ratio were lower among JAK2 V617F positive- vs. JAK2 V617F negative- ET patients (P=0.02 and P=0.002, respectively); whereas VWF:Ag levels were comparable (P=0.96). ET patients harboring the JAK2 V617F mutation were more likely to develop AVWS than were calreticulin-positive patients (70.3% vs. 45.7%, P=0.02), despite lower platelet counts (median 773 vs. 920 X 109/l, P=0.05). In multivariable analysis, age (β=0.26, P=0.002), platelet count (β=-0.38, P<0.001), hemoglobin level (β=-0.22, P=0.01) and JAK2 V617F mutation (β=-0.23, P=0.01) independently predicted VWF:RCo, among ET patients; whereas only platelet count predicted VWF:RCo among PV patients (β=-0.49, P<0.001). Conclusion: Among ET and PV patients, AVWS was common and associated with higher bleeding rates and higher platelet count; nonetheless, most AVWS patients had platelet counts under 1000 X 109/L. Thus, AVWS screening should be included in routine assessment of ET and PV patients. Among ET patients, JAK2 V617F was a main driver for the development of AVWS. Disclosures No relevant conflicts of interest to declare.


2018 ◽  
Vol 35 (6) ◽  
pp. 671-675 ◽  
Author(s):  
Emily Ankus ◽  
Sarah J Price ◽  
Obioha C Ukoumunne ◽  
William Hamilton ◽  
Sarah E R Bailey

Blood ◽  
1990 ◽  
Vol 75 (1) ◽  
pp. 74-81 ◽  
Author(s):  
DJ Kuter ◽  
RD Rosenberg

Abstract The relationship between the bone marrow (BM) megakaryocyte and the circulating platelet was explored. Incremental changes in platelet count were made in rats by infusion of antiplatelet antibody or by platelet transfusion, and the response of megakaryocytes was measured by flow cytometry. Proportional changes in megakaryocyte ploidy were demonstrated: As the platelet count declined, ploidy increased; as the platelet count increased, ploidy decreased. Even moderate degrees of thrombocytopenia and thrombocytosis (48% and 177% of the normal platelet count) were associated with changes in ploidy. These changes were not the results of the technique used to alter the platelet count because reinfusion of platelets after 3 hours of thrombocytopenia prevented any ploidy change. These studies proved that the circulating platelet and the megakaryocyte constitute a classic feedback loop whose activity can be measured by the degree of ploidization of the megakaryocyte. The minimal duration of thrombocytopenia necessary to promote megakaryocyte ploidy changes was approximately 10 hours. Using a BM culture assay, we identified a plasma factor which induced alterations in megakaryocyte ploidy and whose level is inversely proportional to the platelet count.


Blood ◽  
1961 ◽  
Vol 18 (1) ◽  
pp. 73-88 ◽  
Author(s):  
SIDNEY L. SALTZSTEIN

Abstract Accumulation of a lipid, histochemically a phospholipid, in the histiocytes of the splenic pulp was observed in seven patients with thrombocytopenic purpura. Six had classical idiopathic thrombocytopenic purpura with abundant megakaryocytes in the bone marrow. Splenectomy resulted in clinical and hematologic remissions in four of these six, continued thrombocytopenia in the fifth, and in the continued requirement of corticosteroid to maintain a reasonably normal platelet count in the sixth. The seventh patient, who died shortly after splenectomy, had marked hypoplasia of megakaryocytes. Similar lipid accumulation was not seen in more than 700 other spleens, removed for a variety of reasons, reviewed in this study. Platelet phagocytosis has been suggested as a source of the lipid.


1997 ◽  
Vol 33 (5) ◽  
pp. 411-415 ◽  
Author(s):  
LE Smedile ◽  
DM Houston ◽  
SM Taylor ◽  
K Post ◽  
GP Searcy

The medical records of 11 Cavalier King Charles spaniels with idiopathic, asymptomatic thrombocytopenia and large-to-giant platelets were identified from a 10-year retrospective search using the Veterinary Medical Data Base at Purdue University. Eight of the dogs had been treated with various immunosuppressive drugs. Six of the treated dogs remained thrombocytopenic, one was not reevaluated, and one developed a normal platelet count. The underlying etiology of idiopathic, asymptomatic thrombocytopenia in Cavalier King Charles spaniels has not been identified, but this condition could represent a congenital macrothrombocytopenic disorder.


Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 2895-2895
Author(s):  
Gail A. Rock ◽  
David Anderson ◽  
Barrett Benny ◽  
David Barth ◽  
William Clark ◽  
...  

Abstract Introduction The ultimate therapy for TTP is not yet defined. While approximately 85% of patients respond to plasma exchange with FFP, the use of alternative solutions such as cryosupernatant plasma, which is deficient in the high molecular weight forms of vWF. has not been proven by appropriate randomized prospective sample trials. However, it is intellectually appealing. Additionally, the use of the ADAMTS 13 level either to predict disease or outcome has not been resolved. Methods Cryosupernatant plasma (CSP) was compared to solvent detergent treated plasma (SDP) over one cycle (nine days) of plasma exchange (PE) and subsequent procedures as required. Throughout treatment, ADAMTS 13 and protein S levels were followed. Results At the primary end point of one month, 3 of 35 of the CSP and 1 of 27 of the SDP patients died. The average platelet count was 184 × 109 per litre for CSP and 209 × 109 per litre for SDP. While vWF and FVIII were elevated in all patients at entry, no unusually large vWF multimers were seen at any time. At entry 9 patients had ≤ 0–10% ADAMTS 13 and 14 of 62 had normal levels with the rest in between. At presentation only 9 patients had 100% inhibitor activity with no inhibitor in 18 patients. Of the four patients who died, two who received CSP, had 100% enzyme activity at presentation whereas one had no ADAMTS-13 and another had 10%. All 4 patients died within 10 days. Fifteen patients with less than 10% enzyme activity had >1.5 vWF. However, elevated (>3u/mL) vWF was seen in the presence of normal ADAMTS-13 levels. Six months after remission, and in the presence of a normal platelet count, ADAMTS13 remained low in 5 patients and normal in 15.Protein S levels in 41/62 patients studied showed little variation during therapy with values on day 3 and 5, similar to those seen on entry. Conclusion In idiopathic TTP, ADAMTS 13 levels do not correlate with disease, and are not predictive of outcome. While protein S levels in the SDP were lower than those found in FFP, this did not appear to have clinical significance.


2013 ◽  
Vol 31 (15_suppl) ◽  
pp. e18531-e18531
Author(s):  
Jiwen Wang ◽  
Min Luo ◽  
Hanmo Wu ◽  
Liming Sheng ◽  
Dan Su ◽  
...  

e18531 Background: Activated platelet is thought to promote cancer cells growth and metastasis, playing an important role in progression of cancer. However, the association between platelet counts and prognosis of patient with non small cell lung cancer (NSCLC) had not been fully elucidated. The aim of this study is to investigate the prognostic value of platelet counts in resectable NSCLC. Methods: A total of 636 primary NSCLC patients who had curatively resected surgery in Zhejiang Cancer Hospital from November 2006 to January 2011 were retrospectively analyzed. Preoperative platelet counts and clinicopathological factors were collected from the medical record database. Patients were followed up for disease progression free survival (PDS) and overall survival (OS) until January 20, 2013. The association between platelet counts and patients’ outcome were evaluated. Results: In all patients, 13.8% (88/636) had increased platelet count (>300 × 109/L), referred to as thrombocytosis. The proportion of thrombocytosis was significantly higher in male, squamous-cell carcinoma and stage III than that in female, other histological types and early stage NSCLC. Moreover, thrombocytosis was associated with significantly shortened survival. Multivariate Cox analysis showed patient with thrombocytosis not only had a 1.66 time elevated risk for disease progression (95% CI, 1.14-2.41, p=0.009), but also had and a 1.47 time risk for death (95% CI, 1.04-2.08, P=0.029), compared with that in those having normal platelet count. More interestingly, the risk for replase was increased to 3.19 times (95% CI, 1.41-7.23, p=0.006) in stage I NSCLC with thrombocytosis than that in patients with normal platelet count after stratified analysis by stage. Conclusions: Preoperative platelet count is an independent prognostic predictor in operable NSCLC, especially in early stage I NSCLC. Platelet count may serve as a useful indicator and potential target for personalized treatment with antiplatelet reagent.


1948 ◽  
Vol 49 (4) ◽  
pp. 641-646 ◽  
Author(s):  
Russell L. Haden ◽  
R. H. Schneider ◽  
Lee C. Underwood

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