An immunochromatographic test for serological diagnosis of scrub typhus.

A fluorescent immunochromatographic test (FM-ICT) was developed for rapid detection of anti-Orientia tsutsugamushi antibodies in serum samples. The FM-ICT was constructed based on the dual-antigen sandwich method. Truncated 56 kDa outer membrane protein of O. tsutsugamushi strain SJ, was expressed in E. coli and mixed with those of Ptan and Gillam strains. A thin line of the protein mixture was precisely sprayed across a nitrocellulose membrane making this the "Test" line. Polyclonal antibodies (pAbs) to O.tsutsugamushi were sprayed in another line across the membrane making this the "Control" line. Fluorescent microspheres conjugated 56 kDa proteins reacting with sample serum will be captured on the "Test" line if the sample contains antibodies to O.tsutsugamushi. Several experimental parameters were optimized. After optimizing the reaction procedure, the results are visible, within 6 min, with the naked eye under ultraviolet light. The limit of detection (LOD) was determined to be 7.63 ng/mL with prepared polyclonal antibodies. No cross-reaction was observed with sera samples from other febrile diseases. In clinical evaluations, the strips showed 94.92% sensitivity (106/112) and 93.75% specificity (56/60). The FM-ICT we developed will provide a new tool for on-site diagnosis of scrub typhus.

Comparison of catheter-directed thrombolysis with and without percutaneous mechanical thrombectomy for subacute iliofemoral deep vein thrombosis.

OBJECTIVE: To evaluate and compare the treatment efficacy and safety between catheter-directed thrombolysis monotherapy and catheter-directed thrombolysis combined with percutaneous mechanical thrombectomy for patients with subacute iliofemoral deep vein thrombosis. METHODS: We conducted a retrospective analysis of a total of 74 subacute iliofemoral deep vein thrombosis patients who underwent catheter-directed thrombolysis with and without percutaneous mechanical thrombectomy. Patients treated with catheter-directed thrombolysis combined with percutaneous mechanical thrombectomy (percutaneous mechanical thrombectomy group, n = 30) or catheter-directed thrombolysis monotherapy (catheter-directed thrombolysis group, n = 44) were included. The primary endpoints were the clinical efficacy rate of thrombolysis, primary patency, and the incidence of post-thrombotic syndrome (at 12 months diagnosed according to the original Villalta score criteria. Secondary endpoints were the total urokinase dose, the thrombolysis time, the detumescence rate and complications. RESULTS: The percentage of successful thrombolysis for percutaneous mechanical thrombectomy group was higher than that for catheter-directed thrombolysis group (P = 0.045). At the 12-month follow-up, there was no difference in the primary patency (P > 0.05) or the incidence of post-thrombotic syndrome (P = 0.36). Percutaneous mechanical thrombectomy group had significant advantages in reducing urokinase doses and thrombolysis times compared with catheter-directed thrombolysis group for patients with thrombus clearance levels II and III (P < 0.05). CONCLUSION: Catheter-directed thrombolysis combined with percutaneous mechanical thrombectomy performs better in removing vein thrombi, reducing urokinase doses, and shortening thrombolysis times.