부산대학교 도서관

Background: Dengue is an important arboviral disease with about 100 million dengue cases per year, of which, ~5% result in severe disease. Clinical differentiation of dengue from other acute febrile illnesses (AFI) is difficult, and diagnostic blood tests are costly. We evaluated the utility of anti-DENV IgM in urine to identify dengue cases among AFI patients enrolled in a clinical study. Methods: Between May 2012-March 2013, 1538 study participants with fever for ≤7 days were enrolled, a medical history was obtained, and serum and urine specimens were collected. Serum was tested for DENV RNA and anti-DENV IgM. Urine was tested for anti-DENV IgM, and its sensitivity and specificity to detect sera laboratory-positive dengue cases were calculated. We evaluated if urine anti-DENV IgM positivity early (≤5 days post-illness onset [DPO]) and late (6–14 DPO) in the clinical course was associated with dengue severity. Results: Urine anti-DENV IgM sensitivity and specificity were 47.4% and 98.5%, respectively, when compared with serum anti-DENV IgM ELISA results, and 29.7% and 91.1% when compared with serum rRT-PCR results. There was no correlation between urine anti-DENV IgM positivity and patient sex or pre-existing chronic disease. Early in the clinical course, a significantly higher proportion of those who developed dengue with warning signs had anti-DENV IgM in their urine when compared to those without warning signs (20.4% vs. 4.3%). There was no difference in the proportion with urine anti-DENV IgM positivity between severity groups late in the clinical course. Conclusion: While detection of urine anti-DENV IgM lacked adequate diagnostic sensitivity, it is a highly specific marker for laboratory-positive dengue, and its presence early in the clinical course may distinguish those with more severe disease. Further assessment of urine anti-DENV IgM by DPO is warranted to determine its utility as an early diagnostic (and possibly prognostic) marker for dengue. Author summary: Dengue viruses (DENV) are transmitted to humans by infected mosquitoes and the disease, known as dengue, occurs throughout the tropics and subtropics. Dengue diagnostic tests rely on a blood sample taken within two weeks of illness onset. Our primary objective was to determine if urine (an easy sample to collect) could be used to detect dengue cases among patients with an acute febrile illness (AFI). Our second objective was to determine if severe dengue was associated with the detection of anti-DENV IgM antibodies in the urine. We found that detecting urine anti-DENV IgM in AFI patients meant that they likely had dengue, that is, it was a highly specific diagnostic test (few false positives). However, a negative urine test did not rule out dengue, that is, it was not a very sensitive test. Anti-DENV IgM in urine was more likely to be detected in the first five days of illness among patients who later developed severe dengue than those with less severe dengue. These findings suggest that the presence of anti-DENV IgM in urine may be useful to diagnose dengue and may indicate more severe disease if done early in the illness. More studies are needed to confirm these results. [ABSTRACT FROM AUTHOR]