Evaporimetiy in the differentiation of allergic, irritant and doubtful patch test reactions

BACKGROUND/AIMS

The aim is to evaluate, using evaporimetry, the possibility of getting further information supporting clinical reading of allergic, irritant reactions and doubtful patch test reactions.

METHODS

The investigation was carried out on 204 patients (182 female and 22 male, mean age 31.6 years), patch tested routinely as suspects of allergic contact dermatitis. We evaluated 326 reactions (203 allergic, 123 irritant or doubtful).

RESULTS

Mean values pf TEWL were: for the positive allergic reactions, 7.21 (SD, 2.26) at 48 h, 15.77 (SD, 5.50) at 72 h; and for the irritant or doubtful reactions, 7.55 (SD, 1.72) at 48 h, and 5.77 (SD, 1.41) at 72 h. TEWL in the 2 reactions groups at 72 h was significantly different (p<0.01).

CONCLUSIONS

The study shows (i) concordance between the evaporimeter values and the visual score; (ii) at 72 h, the evaporimeter values are increased in the allergic reactions but not in irritant or doubtful reactions; (iii) evaporimetry in the differential diagnoses of patch test reactions was deemed useful.

Evolution of untreated calf deep-vein thrombosis in high risk symptomatic outpatients: the blind, prospective CALTHRO study

The natural history of calf deep-vein thrombosis (DVT) is still uncertain and it is debated whether it warrants to be diagnosed and treated. We aimed to investigate the complication rate of untreated isolated calf DVT (ICDVT). Symptomatic outpatients were prospectively managed with serial compression ultrasonography (SCUS). Those without proximal DVT and with likely pre-test clinical probability (PCP) or altered D-dimer received immediate subsequent complete examination of calf deep veins (CCUS) by a different operator. The result of CCUS was kept blind both to the managing doctor and the patient and disclosed after three months. Primary outcome was the rate of venous thromboembolism at three months. We examined 431 subjects (196 males; median age 68.0 years) in whom five outcomes were recorded (1.2%; 95% confidence intervals [CI]: 0.4-2.7). If CCUS results had been available, outcomes would have been recorded in 3/424 patients (0.7%; 95% CI: 0.2-2.1) with two events in subjects negative at both serial and complete CUS. ICDVT was diagnosed in 65 subjects (15.3%; 95% CI: 12-19); of whom 59 remained uneventful (one was lost to follow-up). A significant higher rate of outcomes was recorded in subjects with than without ICDVT (5/64; 7.8%; 95% CI: 3-17 vs. 3/351; 0.8%; 95% CI: 0-2; p=0.003). However, after excluding two events picked at serial CUS in subjects with ICDVT, the difference became barely significant (3/64; 4.7%; 95% CI: 1-13; p=0.049). Thrombotic evolution of untreated ICDVT in high-risk subjects may be relevant. Larger studies are needed to address this issue.

D-dimer testing to determine the duration of anticoagulation therapy

BACKGROUND

The optimal duration of oral anticoagulation in patients with idiopathic venous thromboembolism is uncertain. Testing of D-dimer levels may play a role in the assessment of the need for prolonged anticoagulation.

METHODS

We performed D-dimer testing 1 month after the discontinuation of anticoagulation in patients with a first unprovoked proximal deep-vein thrombosis or pulmonary embolism who had received a vitamin K antagonist for at least 3 months. Patients with a normal D-dimer level did not resume anticoagulation, whereas those with an abnormal D-dimer level were randomly assigned either to resume or to discontinue treatment. The study outcome was the composite of recurrent venous thromboembolism and major bleeding during an average follow-up of 1.4 years.

RESULTS

The D-dimer assay was abnormal in 223 of 608 patients (36.7%). A total of 18 events occurred among the 120 patients who stopped anticoagulation (15.0%), as compared with 3 events among the 103 patients who resumed anticoagulation (2.9%), for an adjusted hazard ratio of 4.26 (95% confidence interval [CI], 1.23 to 14.6; P=0.02). Thromboembolism recurred in 24 of 385 patients with a normal D-dimer level (6.2%). Among patients who stopped anticoagulation, the adjusted hazard ratio for recurrent thromboembolism among those with an abnormal D-dimer level, as compared with those with a normal D-dimer level, was 2.27 (95% CI, 1.15 to 4.46; P=0.02).

CONCLUSIONS

Patients with an abnormal D-dimer level 1 month after the discontinuation of anticoagulation have a significant incidence of recurrent venous thromboembolism, which is reduced by the resumption of anticoagulation. The optimal course of anticoagulation in patients with a normal D-dimer level has not been clearly established. (ClinicalTrials.gov number, NCT00264277 [ClinicalTrials.gov].).