title: Dengue NS1 antigen as a marker of severe clinical disease.
abstract: BACKGROUND
  Early detection of complications significantly reduces dengue associated mortality and morbidity. We set out to determine if the NS1 rapid antigen detection test could be used as a point of care test to predict severe disease.
  
  
  METHODS
  186 adult patients with confirmed dengue were enrolled during day 3-8 of illness. Clinical and laboratory parameters were recorded during the course of the illness and NS1 antigen levels were determined using both the Panbio dengue early ELISA (Panbio, Australia) and a NS1 rapid antigen detection kit (SD Bioline, South Korea).
  
  
  RESULTS
  59.1% of patients presented to hospital on day 5-6 of illness when NS1 antigen positivity was significantly (p = 0.008) associated with severe dengue (odds ratio 3.0, 95% CI 1.39 to 6.47) and the NS1 antigen levels were significantly higher (p = 0.03) in those who went on to develop shock. Serum NS1 antigen levels significantly (p < 0.0001) and inversely correlated with the total white cell counts and lymphocyte counts. The bedside NS1 test showed comparable sensitivity (97.4%) and specificity (93.7%) to the laboratory NS1 test in our setting and cohort.
  
  
  CONCLUSIONS
  NS1 antigen positivity is associated with a higher risk of developing severe dengue especially when positive beyond day 5 of illness in our cohort, and while further validation studies are required, the test can therefore potentially be used as a bedside point of care test as a warning sign of severe dengue.
authors.forename: Shiran Ajith
authors.initials: SA
authors.lastname: Paranavitane
authors.forename: Laksiri
authors.initials: L
authors.lastname: Gomes
authors.forename: Achala
authors.initials: A
authors.lastname: Kamaladasa
authors.forename: Thiruni N
authors.initials: TN
authors.lastname: Adikari
authors.forename: Nilanka
authors.initials: N
authors.lastname: Wickramasinghe
authors.forename: Chandima
authors.initials: C
authors.lastname: Jeewandara
authors.forename: Narangoda Liyanage Ajantha
authors.initials: NL
authors.lastname: Shyamali
authors.forename: Graham Stuart
authors.initials: GS
authors.lastname: Ogg
authors.forename: Gathsaurie Neelika
authors.initials: GN
authors.lastname: Malavige
mesh_terms: D000328:Adult; D000369:Aged, 80 and over; D000956:Antigens, Viral / Q000097:blood*; D019540:Area Under Curve; D015415:Biomarkers / Q000097:blood; D003716:Dengue Virus / Q000276:immunology*; D042241:Early Diagnosis; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010996:Pleural Effusion / Q000821:virology; D019095:Point-of-Care Systems; D012372:ROC Curve; D012680:Sensitivity and Specificity; D019595:Severe Dengue / Q000097:blood / Q000175:diagnosis* / Q000276:immunology; D012720:Severity of Illness Index; D017361:Viral Nonstructural Proteins / Q000097:blood*; D055815:Young Adult
chemical_list: D000956:Antigens, Viral; D015415:Biomarkers; D017361:Viral Nonstructural Proteins