Single nucleotide polymorphisms in inflammation-related genes are associated with venous thromboembolism.

BACKGROUND: Various genetic risk factors are known to increase the risk of venous thromboembolism (VTE). Increasing evidence suggests a "cross-talk" between the coagulation and inflammatory cascade. Therefore, polymorphisms in genes involved in inflammation may influence susceptibility towards VTE. The aim of the study was to investigate the role of single nucleotide polymorphisms (SNPs) in inflammation genes for susceptibility towards VTE. METHODS: The study group consisted of 108 (47 men and 61 women) Dutch patients with documented VTE and 325 healthy controls from the same geographical area (117 men and 208 women). Odds ratios (OR) and 95% confidence intervals (95% CI) for VTE separately and if indicated by gender were calculated to assess whether genotype and allele frequency were associated with thrombosis. RESULTS: Heterozygosity for SNP -899C/T of the interleukin 1-alpha gene (IL1A -899C/T) was under-represented in VTE patients compared to the control group (OR=0.51, 95% CI 0.32-0.82). The IL6 -174 CC genotype was more frequent in male patients with VTE compared to male controls (OR=4.06, 95% CI 1.43-11.5). Female patients carried significantly more IL13 (intron3) TT genotype (OR=5.60, 95% CI 1.94-18.5) compared to female controls. The allelic frequency of IL4 -589 T allele was significantly increased in female patients (OR=1.72, 95% CI 1.05-2.81) in contrast to men where no differences were observed. CONCLUSION: Four SNPs in inflammatory-related genes of IL1A, IL4, IL6, and IL13 may be associated with VTE. These results need to be confirmed in independent groups with larger number of patients.

Harmonization of fibrinogen assay results: study within the framework of the Dutch project 'Calibration 2000'.

In a Dutch project for harmonization of fibrinogen assays, the commutability of potential calibrators for fibrinogen was assessed by means of a twin-study design, which is, in essence, a multicentre, split-patient sample, between-field-methods protocol. The study consisted of simultaneous analysis of fresh-frozen patient plasmas and three potential calibrators for fibrinogen by 48 Dutch laboratories forming 24 couples. The state-of-the-art intralaboratory standard deviation was used to assess the commutability of the potential calibrators. The potential calibrators were commutable for the Clauss, but not for the prothrombin time (PT)-derived assays. One potential calibrator was used in an attempt to harmonize fibrinogen assay results in a Dutch field study. The interlaboratory coefficient of variation (CV) of three out of four test samples could be reduced significantly using the common calibrator. The average overall CV for the four test samples was 10.3% using the routine measurements and 7.8% using the common calibrator. Despite the reduction in the overall CV, the bias between Clauss and PT-derived assay results in two coumarin test samples could not be eliminated.

The usefulness of five D-dimer assays in the exclusion of deep venous thrombosis.

D-Dimer measurement is a promising tool in the exclusion of venous thrombosis. New d-dimer assays have been introduced, but need clinical validation. Our objective was to evaluate the clinical usefulness of four relatively new d-dimer assays and a classical ELISA in outpatients suspected for deep venous thrombosis. In 537 patients, participants in a large prospective management study using a clinical probability score and a d-dimer measurement (Tina-quant), additional samples were taken for d-dimer measurement using the Asserachrom ELISA, the VIDAS New, the STA-LIA and the Miniquant assay. Performances of each test were calculated using clinical data during a 3-month follow-up. Thrombosis was detected in 224 patients (42%). The area under the ROC curve was significantly higher for the Tina-quant as compared to the other assays. Using standard cut-off values, sensitivity, negative predictive value (NPV) and specificity of the Asserachrom were 97, 94 and 33%, respectively. For the VIDAS New, values were 100, 96 and 8%, respectively. The Tina-quant showed values of 99, 98 and 41%, respectively, and the STA-LIA 98, 95 and 32%. Values for the Miniquant were 95, 94 and 52%. The d-dimer assays in our study all show a high sensitivity and negative predictive value, but none of the assays reached an NPV of > 98% at standard cut-off values. d-Dimer assays with a low specificity still necessitate additional diagnostic tests in the majority of the patients.

Combination of a normal D-dimer concentration and a non-high pretest clinical probability score is a safe strategy to exclude deep venous thrombosis.

BACKGROUND: Serial ultrasonography is reliable for the diagnosis of deep venous thrombosis in symptomatic patients, but the low prevalence of thrombosis in this group renders the approach costly and inconvenient to patients. We studied the clinical validity of the combination of a pretest clinical probability score and a D-dimer test in the initial evaluation of patients suspected of deep venous thrombosis. METHODS AND RESULTS: Patients with a normal D-dimer concentration (<500 fibrin equivalent units [FEU] microg/L) and a non-high probability score (<3) had no further testing. Patients with a normal D-dimer concentration and a high probability score (> or =3) underwent one ultrasonogram. Serial ultrasonography was performed in patients with an abnormal D-dimer concentration. Patients were followed for 3 months. A total of 812 patients were evaluable for efficacy. Only 1 of 176 patients (0.6%; 95% CI, 0.02% to 3.1%) with a normal D-dimer concentration and a non-high probability score developed thrombosis during follow-up. A normal D-dimer concentration and a high probability score were found in 39 patients; 3 of them (7.7%; 95% CI, 1.6% to 20.9%) had thrombosis at presentation, and one (2.8%; 95% CI, 0.07% to 14. 5%) developed pulmonary embolism during follow-up. In 306 of 597 patients (51.3%) with an abnormal D-dimer concentration, thrombosis was detected by serial ultrasonography. Six patients (2.1%; 95% CI, 0.8% to 4. 4%) developed thrombosis during follow-up. No deaths due to thromboembolism occurred during follow-up. The total need for ultrasonography was reduced by 29%. CONCLUSION: The combination of a non-high pretest clinical probability score and a normal D-dimer concentration is a safe strategy to rule out deep venous thrombosis and to withhold anticoagulation.

S100 protein content of umbilical cord blood in healthy newborns in relation to mode of delivery.

BACKGROUND: Early detection and quantification of brain damage in neonatal asphyxia is important. In adults, S100 protein in blood is associated with damage to the central nervous system. OBJECTIVE: To determine whether S100 protein can be detected in arterial and venous cord blood of healthy newborns and to relate S100 protein concentrations in cord blood to mode of delivery. METHOD: S100 protein levels in umbilical cord blood of 81 healthy infants were determined. RESULTS: S100 protein was present in arterial (median concentration 1.62 micro g/l) and venous (median concentration 1.36 micro g/l) cord blood. Levels were significantly higher in vaginal births (median arterial concentration 1.72 micro g/l; median venous concentration 1.48 micro g/l) than births by caesarean section (1.51 micro g/l and 1.26 micro g/l respectively). CONCLUSION: More research is necessary to determine whether S100 protein is a useful marker in neonatal asphyxia.

Treatment of primary Sjögren's syndrome with D-penicillamine: a pilot study.

BACKGROUND: Up to now no satisfying systemic treatment is available for patients with primary Sjögren's syndrome. METHODS: In a prospective, open study we investigated the effect of D-penicillamine (first three months 250 mg/day, next three months 500 mg/day) on clinical and immunological parameters in 19 patients with primary Sjögren's syndrome and a mean disease duration of 3.8 years. RESULTS: Eight patients had to stop treatment mainly due to severe (reversible) loss of taste. Clinically, a statistically significant increase in basal salivary flow was observed after three months (p<0.05). In addition, improvement was noted in the Schirmer test and stimulated parotid salivary flow after six months, but these differences were not statistically significant. Laboratory values showed a decrease in ESR (p<0.05) and levels of IgA and IgM (both p<0.02) after six months, a decrease in levels of IgA-Rf and IgM-Rf after three months (both p<0.05), and an increase in haemoglobin level (p<0.05). CONCLUSION: From this pilot study we conclude that the treatment of primary Sjögren's syndrome with D-penicillamine has only marginal beneficial effects. Together with its clear side effects this means that D-penicillamine is unsuitable for this indication.