Reference intervals as a tool for total quality management

The more traditional, widespread and practiced method for interpreting the laboratory results is based on the comparison made with reference intervals. Nevertheless, the creation of appropriate reference intervals requires careful planning, monitoring and documentation of every aspect of the study, including the selection of the reference population (encompassing selection of homogeneous groups of reference according to ethnicity, geographical origin and environmental conditions, stratification according to age and gender, definition of health status) along with the use of the most appropriate statistical tools. In the very next future, the longitudinal comparison of laboratory results might probably replace the current use of reference intervals

Red wine and cardiovascular health the "French Paradox" revisited

The healthful and nutritive properties of wine have been acknowledged for thousands of years, but the observation that moderate consumption of red wine on a regular basis may be preventative against coronary disease is recent. Dr Renaud, a scientist working at the Bordeaux University in France, suggested wine consumption explains the "French Paradox", the low incidence of heart attacks in France regardless of a remarkable dietary intake of saturated fats and alcohol. After nearly 20 years of research, there is now mounting evidence that light to moderate wine intake is beneficial for the cardiovascular health, acting through a variety of mechanisms that target all the crucial steps of atherosclerosis, from early formation of the atherosclerotic plaque to its life-threatening complications (ulceration, thrombosis, vessel occlusion and infarction). These effects are attributable to the synergic properties of several biochemical components of wine (alcohol, resveratrol, and especially polyphenolic compounds), particularly the red varieties. This article reviews the leading clinical observations and the hypothesized biological mechanisms that strongly support the cardiovascular benefits of moderate red wine consumption on cardiovascular health and that would make red wine a promising therapeutic supplement to prevent and even perhaps treat coronary artery disease

The use of recombinant activated factor VII in platelet-associated bleeding

Recombinant activated factor VII (rFVIIa) was originally developed for the treatment of spontaneous and surgical bleeding of hemophiliacs with inhibitors. Along with the elucidation of its molecular mechanism of action, rFVIIa has been successfully used over the last few years in a wide range of non-hemophilic bleeding conditions. The aim of this review is to summarize the current clinical experience on the use of rFVIIa in the management of bleeding associated with congenital or acquired platelet disorders

Blood doping by cobalt. Should we measure cobalt in athletes?

BACKGROUND: Blood doping is commonplace in competitive athletes who seek to enhance their aerobic performances through illicit techniques. PRESENTATION OF THE HYPOTHESIS: Cobalt, a naturally-occurring element with properties similar to those of iron and nickel, induces a marked and stable polycythemic response through a more efficient transcription of the erythropoietin gene. TESTING THE HYPOTHESIS: Although little information is available so far on cobalt metabolism, reference value ranges or supplementation in athletes, there is emerging evidence that cobalt is used as a supplement and increased serum concentrations are occasionally observed in athletes. Therefore, given the athlete's connatural inclination to experiment with innovative, unfair and potentially unhealthy doping techniques, cobalt administration might soon become the most suited complement or surrogate for erythropoiesis-stimulating substances. Nevertheless, cobalt administration is not free from unsafe consequences, which involve toxic effects on heart, liver, kidney, thyroid and cancer promotion. IMPLICATIONS OF THE HYPOTHESIS: Cobalt is easily purchasable, inexpensive and not currently comprehended within the World Anti-Doping Agency prohibited list. Moreover, available techniques for measuring whole blood, serum, plasma or urinary cobalt involve analytic approaches which are currently not practical for antidoping laboratories. Thus more research on cobalt metabolism in athletes is compelling, along with implementation of effective strategies to unmask this potentially deleterious doping practic

Comparison of platelet function between sedentary individuals and competitive athletes at rest

BACKGROUND: There are controversial evidences on the effect of different types and workloads of physical exercise on primary hemostasis. In particular, little is known on the chronic influence of a strenuous and regular aerobic training regimen on platelet function. METHODS: The aim of this investigation was to compare platelet function between sedentary controls and trained athletes at rest and to evaluate whether a greater amount of exercise performed in professional cyclists may contribute to increased platelet chronic responsiveness compared to both elite cyclists and sedentary individuals. Platelet's ability to adhere and aggregate was assayed following a 12–24 h resting period in 49 active professional male road cyclists, 40 elite male cyclists and 43 matched sedentary healthy male volunteers, by the platelet function analyzer 100 (PFA-100). RESULTS AND DISCUSSION: Mean values of the collagen-epinephrine test did not differ between controls and athletes (sedentary controls: 111 ± 33 s; elite athletes: 113 ± 26 s, p = 0.93; professional athletes: 120 ± 33 s; p = 0.33), whereas mean values of the collagen-ADP test displayed a slightly but significant trend towards decreased values when comparing sedentary controls (83 ± 21 s) with either elite (77 ± 11 s, p < 0.01) or professional (75 ± 16 s, p < 0.01) athletes. CONCLUSION: The trend towards slightly lower collagen-ADP values are suggestive for a modest but significant chronic activation of primary hemostasis, highlighting the need to set appropriate reference ranges for the PFA-100 when evaluating primary hemostasis in physically active subjects

Comparison of 2 Methods for the Calculation of Estimated Glomerular Filtration Rate

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Plasma D-dimer concentration in patients with systemic sclerosis

BACKGROUND: Systemic sclerosis (SSc) is an autoimmune disorder of the connective tissue characterized by widespread vascular lesions and fibrosis. Little is known so far on the activation of the hemostatic and fibrinolytic systems in SSc, and most preliminary evidences are discordant. METHODS: To verify whether SSc patients might display a prothrombotic condition, plasma D-dimer was assessed in 28 consecutive SSc patients and in 33 control subjects, matched for age, sex and environmental habit. RESULTS AND DISCUSSION: When compared to healthy controls, geometric mean and 95% confidence interval (IC95%) of plasma D-dimer were significantly increased in SSc patients (362 ng/mL, IC 95%: 361–363 ng/mL vs 229 ng/mL, IC95%: 228–231 ng/mL, p = 0.005). After stratifying SSc patients according to disease subset, no significant differences were observed between those with limited cutaneous pattern and controls, whereas patients with diffuse cutaneous pattern displayed substantially increased values. No correlation was found between plasma D-dimer concentration and age, sex, autoantibody pattern, serum creatinine, erythrosedimentation rate, nailfold videocapillaroscopic pattern and pulmonary involvement. CONCLUSION: We demonstrated that SSc patients with diffuse subset are characterized by increased plasma D-dimer values, reflecting a potential activation of both the hemostatic and fibrinolytic cascades, which might finally predispose these patients to thrombotic complications

Increased D-dimer value and occult cancer in the absence of detectable thrombosis.

Fibrin formation and removal occurs continuously during the development of malignancy. Accordingly, hemostatic disorders in cancer patients are a rather frequent observation and range from asymptomatic laboratory changes to massive thromboembolism or haemorrhage. We document the case of an asymptomatic women, who was enrolled as a healthy control in a study and showed up with a substantially increased D- dimer value. After ruling out the most probable sources of D-dimer elevation, such as thrombosis, inflammation and trauma, she underwent laboratory and radiological investigations for malignancy, which were consistent with a colorectal metastatic adenocarcinoma. This case allow us to hypothesize that screening for occult malignancy in the presence of apparently inexplicable elevated D-dimer values may be taken into consideration