Elevated Plasma Angiopoietin-like 4 Protein Levels in Adult Patients with Dengue.

Dengue virus infection can cause severe complications due to vascular leakage. Angiopoietin-like protein 4 (ANGPTL4) regulates vascular permeability, but its role in dengue pathogenesis is unclear. This study investigated the association between plasma ANGPTL4 levels and dengue severity in Singapore adults. Plasma samples from 48 dengue patients (24 severe and 24 non-severe) during acute and convalescent phases were selected from the prospective COhort study on progression of DENgue severity in Singapore adults (CODEN) cohort. The CODEN was conducted at the National Centre for Infectious Diseases, Tan Tock Seng Hospital, from June 2016 to January 2020. ANGPTL4 levels were measured and compared to 152 healthy controls. Logistic regression assessed the relationship between plasma ANGPTL4 concentrations and disease severity. There were no statistically significant differences in ANGPTL4 levels between severe and non-severe dengue patients during acute (677.4 vs. 909.1 pg/mL, p = 0.4) or convalescent phases (793.7 vs. 565.6 pg/mL, p = 0.96). Plasma ANGPTL4 levels were significantly elevated during acute dengue (4634.3 pg/mL) versus healthy controls (907.4 pg/mL), declining during convalescence. Compared to the lowest tertile, the adjusted odds ratios for severe dengue were 0.36 (95%CI: 0.08-1.65, p = 0.190) for medium tertile and 0.57 (95%CI: 0.13-2.49, p = 0.456) for high tertile. Among patients with high ANGPTL4 levels (>5000 pg/mL), 36.4% developed severe complications, including significant plasma leakage. Plasma ANGPTL4 levels were significantly higher in dengue patients than controls, suggesting its potential as a biomarker, which warrants future detailed investigations. Larger prospective studies with serial sampling, including pediatric populations, may clarify the role of ANGPTL4 in severe dengue.