Increased factor VIII related antigen in cerebral thrombosis

Von Willebrand factor, P-selectin and fibrinogen levels in patients with acute ischaemic and haemorrhagic stroke, and their relationship with stroke sub-type and functional outcome

Although ischaemic stroke is associated with accentuated platelet function, it remains unclear whether this applies to all sub-types, especially lacunar infarcts, which differ from cortical infarction in their patho-aetiology. Similarly, conflicting evidence suggests that haemorrhagic stroke may, or may not, be associated with a hypothrombotic state. Levels of von Willebrand factor (vWF), fibrinogen, and P-selectin were measured within 48 h of ictus in 163 patients with acute ischaemic stroke and 40 patients with acute primary intracerebral haemorrhage, and 33 age, gender and race matched-controls. vW F (IU/dl) was significantly increased in both cortical and lacunar ischaemic stroke, and haemorrhagic stroke, as compared with controls, median (semiquartile range): 158 (25) vs 144 (19) vs 147 (24) vs 114 (16), respectively. Similarly, fibrinogen (g/litre) was increased: 4.80 (0.90) vs 4.65 (0.70) vs 4.35 (0.83) vs 3.70 (0.70). In contrast, soluble P-selectin (ng/ml) was increased in cortical stroke as compared with lacunar infraction patients or controls: 408 (101) vs 300 (108) vs 324 (121), respectively; P-selectin was not increased in haemorrhagic stroke, 360 (153). Both vW F and fibrinogen correlated with 3-month functional outcome (modified Rankin score): r = 0.371 (2 P = 0.0006), and r = 0.195 (2 P = 0.042), respectively; however, P-selectin was not associated with outcome: r = 0.188 (2 P = 0.084). The results suggest that increases in vW F and fibrinogen in all types of stroke reflect an acute phase response; in contrast, increased soluble P-selectin levels in cortical stroke, but not lacunar infarction, suggest that platelets contribute to the patho-aetiology of some subtypes of ischaemic stroke.

What supports the role of alcohol as a risk factor for stroke?

For more than 30 years, clinical observations to link alcohol abuse and stroke have accumulated in several countries. Studies of general populations have indicated that the risk for stroke increases with increasing alcohol consumption. Studies of young victims of stroke where the classical risk factors of stroke are uncommon, have demonstrated that even occasional heavy drinking carries an increased risk for stroke. In particular, the increased occurrence of strokes during weekends, the very time of heavy alcohol consumption in non-alcoholics, supports this notion. Alcoholics seem to get their strokes at an earlier age than non-alcoholics. Paradoxically, the published evidence has implicated drinking in both ischemic and hemorrhagic strokes, which suggests that there may be more than one mechanism by which alcohol can increase the risk. Strokes seem to be precipitated during the alcohol intoxication itself rather than the following withdrawal syndrome, but the contributing mechanisms, except for bleedings caused by external violence, are unknown. Alcohol can produce fluctuations in platelet reactivity and untoward interactions with certain drugs, but it remains to be demonstrated that such effects are temporally related to the onset of ischemic and hemorrhagic strokes.

Sequential changes in von Willebrand factor and soluble thrombomodulin in acute ischemic stroke

The purposes of the present study were to investigate sequential changes in plasma von Willebrand factor (vWf) activities and serum soluble thrombomodulin (sTM) concentrations, compared with white blood cell (WBC) counts, and to disclose the different roles of vWf and sTM in acute ischemic stroke. Forty-three acute ischemic stroke patients admitted to our hospital within 48 hours from onset were enrolled. Plasma vWf activities, serum sTM concentrations, and WBC counts were measured at the acute stage and 1 and 6 months after admission. The time course study revealed that vWf activities increased more markedly 1 month after admission than at the acute stage. However, sTM concentrations were low at the acute stage and increased sequentially at 1 month (not significantly) and 6 months (significantly) after admission. In contrast, elevated WBC counts at the acute stage decreased significantly at 1 and 6 months after admission. Raised vWf activities 1 month after admission were suggested to occur through continuous endothelial dysfunction or repair and platelet activation, compared with the acute stage, and decreased sTM at the acute stage through down-regulation of sTM synthesis by acute inflammatory response after acute ischemic stroke, compared with the chronic stage.

Do hemophilia A and von Willebrand disease protect against carotid atherosclerosis? A comparative study between coagulopathics and normal subjects by means of carotid echo-color Doppler scan

Atherosclerosis is a multifactorial disease caused by genetic and environmental factors with important clinical sequelae. The aim of this study was to evaluate the degree of carotid atherosclerosis by echo-color Doppler scan in a group of patients affected by hemophilia A and von Willebrand disease versus a group of normal subjects apparently free of atherosclerotic risk factors. All coagulopathics and normal patients who came to our Internal Medicine Department (Padua Hospital) underwent physical exam, blood analysis, standard electrocardiogram, chest x-ray, echo-color Doppler scan, and a thorough history. We examined 156 subjects, 76 coagulopathics (46 men, 30 women) and 77 normals (37 men, 40 women). Coagulopathics were affected by hypertension in 28.9% of cases, diabetes mellitus in 6.5%, dislipidemia in 17.1%, smoke in 39.4%, and obesity in 36.8% (p < .05). Echo-color Doppler scan revealed carotid plaques in 27.2% of control patients versus 13.1% of coagulopathics (p < .05). Hemophilics and subjects with von Willebrand disease with a more serious illness had fewer plaques than those with lighter defects. Coagulopathics showed 23.6% of the plaques we revealed on the whole, versus 76.3% of control subjects (p < .01), with a lighter degree of stenosis (p < .01). Our data demonstrate that patients with hemophilia A and von Willebrand disease have fewer carotid plaques and a smaller degree of carotid stenosis than normal subjects of the same sex and age. These data seem to strengthen the hypothesis that blood coagulation defects may allow protection against carotid atherosclerosis and its sequelae.

von Willebrand factor, endothelial cell damage and atherosclerosis

von Willebrand factor (vWf) is an interesting and potentially important molecule whose biology in health and disease warrants attention. A growing body of knowledge now suggests that plasma levels of this specific product of the endothelial cell may have potential as a marker for the assessment of endothelial injury in vivo. As its functions include platelet aggregation and mediation of platelet adhesion to the subendothelium, it may also have a role in the pathogenesis of progression of atherosclerosis. In comparison to asymptomatic controls, increased levels of vWf are found in atherosclerotic vascular disease and in the presence of several of its major risk factors (smoking, hypercholesterolaemia, hypertension, obesity and diabetes). High plasma levels of vWf are also associated with the prediction of adverse clinical events such as myocardial infarction and poor outcome following arterial surgery, possibly by the promotion of thrombus formation. These and other studies indicate that research directed towards determining whether therapy to reduce levels of vWf also influences the progression of arterial disease should prove to be profitable.

Quantitative and qualitative assessment of plasma von Willebrand factor in classic Kaposi's sarcoma

BACKGROUND

von Willebrand factor (vWF) is synthesized almost exclusively by endothelial cells and is stored there as ultra-high-molecular-weight multimers. The vWF multimers that are detected in the plasma are smaller than those stored within the endothelium. In two previous studies, comprising small series of cases with classic Kaposi's sarcoma (KS), an endothelium-derived tumor, increased levels of plasma von Willebrand factor antigen (VWF:Ag, the antigenic structure) were reported, suggesting that vWF:Ag may be a marker of endothelium proliferation.

OBJECTIVE

Our purpose was to investigate the quantitative as well as qualitative alterations of plasma vWF in a large series of patients with classic KS at various stages of the disease.

METHODS

Levels of plasma vWF:Ag were studied in 38 patients with classic KS confined to the skin at various stages of the disease and compared with a control group. Thirty-three patients had active KS (i.e., with skin lesions) and five were in remission. In five patients with active KS multimeric analysis of plasma vWF was also performed.

RESULTS

The levels of vWF:Ag were significantly higher among KS patients than in the control group (n = 29, p < 0.01). Levels of vWF:Ag were also significantly higher in patients with active disease as compared with those in remission (p < 0.05). No correlation was found between vWF:Ag levels and the extent of KS. Analysis of the multimeric pattern of plasma vWF showed enhanced staining of all bands, particularly the intermediate and high molecular weight forms, which resemble the endothelial forms as opposed to normal circulating vWF multimers.

CONCLUSION

Quantitative as well as qualitative alterations in plasma vWF were found in patients with KS, which may reflect the destruction or activation of endothelial cells within the lesions. vWF:Ag may serve as a marker of disease activity in classic KS; however, it is not a good marker for the extent of the disease.

Cutaneous and plasma values of von Willebrand factor in AIDS: a marker of endothelial stimulation?

Patients infected by the human immunodeficiency virus (HIV) represent a model in which endothelial proliferation and/or damage are of concern. We studied Von Willebrand factor (VWF) plasma values as a presumed marker of endothelial proliferation in patients with the lymphadenopathy syndrome (LAS) (n = 45), AIDS-related Kaposi's sarcoma (KS) (n = 23), and AIDS opportunistic infections (n = 9), in comparison with normal controls (n = 19) and classical KS (n = 12). VWF was increased in AIDS patients with KS (p less than 10(-6)), in AIDS patients without KS (p less than 10(-7)), and to a lesser extent in classical KS (p less than 10(-3)) and LAS (p less than 10(-2] patients. To evaluate the diffusion of the vascular proliferation in HIV-infected patients, we studied the number of vessels within the superficial dermis of clinically uninvolved skin by an indirect immunoperoxidase method. We used an antibody directed against VWF in skin biopsies from 20 LAS patients and 10 AIDS-related KS patients compared to 11 controls and 10 classical KS patients. An increase in the number of blood vessels in normal skin was found in LAS (p less than 10(-2)), classical KS (p less than 0.05), and AIDS-related KS (p less than 10(-2]. Statistical studies and comparisons between plasma and cutaneous values of VWF indicate that plasma VWF is a good marker of endothelial damage but a poor marker of vascular proliferation in HIV-infected patients.

Platelet function and coagulation studies in patients with mitral valve prolapse

Twenty-eight consecutive patients with mitral valve prolapse (MVP), seven of whom had previous cerebrovascular disorders (CVD), were studied for platelet function and coagulation tests. While platelet function tests were found to be normal with the exception of platelet aggregation rate (PAR), there was a significant rise of factors VIII vWF:Ag (Von Willebrand) and (FPA) fibrinopeptide A. Six cases had high levels of both these factors, suggesting the existence of a particular subset of patients with MVP, with a higher risk of thromboembolic episodes, although only three out of seven patients with previous CVD had either FPA or VIII vWF:Ag levels. The broad spectrum of subjects with MVP probably explains the different results obtained when studying platelet function and coagulation factors. Therefore, larger population studies and prolonged follow-up of cases with either coagulation abnormalities similar to the ones found in the present report and/or altered platelet function tests are suggested to discover if it is possible to detect patients with a potential for thromboembolism.