Diagnostic value of D-dimer in outpatients with suspected deep venous thrombosis receiving oral anticoagulation.

D-dimer has proved a useful diagnostic tool for the exclusion of deep venous thrombosis (DVT). The objective of this paper was to evaluate the diagnostic performance of a diagnostic algorithm combining clinical probability and D-dimer in outpatients receiving oral anticoagulant treatment (OAT) similar to those regularly applied to nonanticoagulated individuals. We enrolled 70 outpatients on OAT who presented with clinically suspected DVT; a standard diagnostic algorithm including clinical evaluation using the modified Wells score and a quantitative immunoturbidimetric D-dimer assay (STA Liatest D-Di; Diagnostica Stago, Asniéres sur Seine, France) was used. A 3-month follow-up period was applied for those patients in whom DVT was initially excluded. The prevalence of DVT was 18.5% (13/70); four of the diagnoses were made during the 3-month follow-up period. The sensitivity, specificity and negative predictive value of D-dimer were 69.2% (95 confidence interval, 42.4-87.3), 47.4% (95% confidence interval, 35.0-60.1) and 87.1% (95% confidence interval, 71.1-94.9), respectively. In conclusion, D-dimer is of limited value in outpatients on OAT presenting with clinically suspected DVT and should be omitted in such individuals; these patients should always undergo compression venous ultrasound, and repeat ultrasonography within 1 week might be warranted in cases with an initial negative examination.

Tobacco as an allergen in bronchial disease.

BACKGROUND: Skin testing and sera measurements have verified the existence of tobacco specific IgE. However, the few published studies on this matter report conflicting results concerning their clinical significance. OBJECTIVE: To verify if a specific clinical allergenic response against tobacco might be possible in allergenic and nonallergenic bronchial diseases. METHODS: We performed a cross-sectional observational case-control analysis on 180 patients with asthma, chronic obstructive pulmonary disease (COPD), and bronchial carcinoma and controls who were randomly chosen. Skin prick tests and serum specific IgE to tobacco and related allergens, bronchial challenge with cigarettes and tobacco extract, patch tests with tobacco and nicotine, sodium dodecyl sulfate-polyacrylamide gel electrophoresis immunoblotting, and Enzyme AllergoSorbent Test (EAST) inhibition were performed. RESULTS: Twenty-eight patients had positive tobacco skin prick test results. The association among positive skin prick test results, IgE, and bronchial challenge was strong (P < .001). Tobacco sensitivity was higher in patients with pollen asthma than in patients with COPD and carcinoma and negative in patients with intrinsic asthma and controls. A positive bronchial challenge result was related to the length of habit (P < .001) and the tobacco index in patients who had stopped smoking (P < .001). Delayed bronchial and patch response was more common in patients with COPD (P < .001). Tobacco IgE response (EAST) was related to sensitivity to Lolium perenne (rye grass) pollen (P < .001) but not to other vegetables that belong to the Solanaceae family. EAST inhibition showed cross-reactivity between tobacco and Lolium pollen. CONCLUSIONS: Tobacco may be responsible for a specific IgE response. Patients with pollen asthma were those with more positive responses to tobacco due to cross-reactivity between Lolium and tobacco allergens.

Combined D-dimer and clinical probability are useful for exclusion of recurrent deep venous thrombosis.

It is estimated that up to one-third of patients with a history of deep venous thrombosis (DVT) present with symptoms of recurrent DVT. Our objective was to investigate both the diagnostic value of D-dimer (DD) and safety of a standard diagnostic algorithm including clinical assessment, plasma DD levels, and compression venous ultrasound as diagnostic tools in outpatients presenting with clinically suspected acute recurrent DVT of the lower limbs. We have enrolled 105 outpatients with a previous history of confirmed DVT and clinically suspected recurrent DVT. A 3-month follow-up period was carried out for patients in whom DVT was initially excluded. Prevalence of DVT in our study population was 44.8% (47/105). DD was negative in 17.1% of cases (18/105) and DVT could be ruled out in 15.2% of patients evaluated (16/105) on the basis of an unlikely clinical probability and a negative DD result. Only one false negative DD result in a patient scored as likely for DVT was found. Sensitivity, specificity, positive and negative predictive value of DD for the diagnosis of DVT were 97.9% (95% CI 88.9-99.6%), 29.3% (95% CI 19.2-42.0%), 52.9% (95% CI 42.5-63.0) and 94.4% (95% CI 74.2%-99.0), respectively. Sensitivity was 100% (95% CI 75.7-100) in the group of patients in whom DVT was considered unlikely. A diagnostic strategy combining clinical evaluation and DD has proved to be useful for the exclusion of DVT in subjects with clinically suspected recurrent DVT, especially in patients included in the lower clinical pretest probability group.