Comparison of Colorimetric (Enzyme-Linked Immunosorbent Assay (ELISA)) and Chemiluminescent Immunoassay (CLIA) Methods for Detection of Dengue Nonstructural Protein 1 (NS1) Antigen in Acute Dengue Infection.

BACKGROUND

Early diagnosis of dengue virus infection is essential for timely clinical management. Detection of nonstructural protein 1 (NS1) antigen plays an important role during the acute phase of illness. This study aimed to compare the diagnostic performance of enzyme-linked immunosorbent assay (ELISA) and chemiluminescence immunoassay (CLIA) for NS1 antigen detection in acute dengue infection.

METHODS

This cross-sectional comparative study included 50 patients with suspected acute dengue infection. Serum samples were collected at admission (day 0) and on days 2 and 4 of illness. Dengue infection was confirmed using real-time polymerase chain reaction (RT-PCR) as the reference standard. NS1 antigen detection was performed using NOVATEINBIO ELISA and MAGLUMI® CLIA assays. Dengue IgM and IgG antibodies were also assessed using ELISA. Sensitivity, specificity, positive predictive value, negative predictive value, and diagnostic accuracy were calculated for both methods.

RESULTS

RT-PCR confirmed dengue infection in 39 (78%) of cases. NS1 ELISA demonstrated a sensitivity of 89.74% and specificity of 81.81%, whereas CLIA showed higher sensitivity (94.87%) and specificity (90.90%). NS1 antigen levels were highest during early illness and declined by day 4. IgM antibodies became detectable in 33 patients by day 4, while IgG antibodies remained negative. Hematological findings demonstrated progressive leukopenia and thrombocytopenia.

CONCLUSION

CLIA demonstrated higher sensitivity and specificity compared with ELISA for NS1 antigen detection. Its automation and improved performance make it a valuable tool for the early diagnosis of dengue infection in endemic settings.