title: NS1 antigen as an early diagnostic marker in dengue: report from India.
abstract: Detection of specific IgM antibodies by ELISA forms the mainstay for diagnosis of dengue infection. However, IgM antibodies develop after 4 to 5 days of infection. The methods for early diagnosis include virus isolation and reverse transcriptase polymerase chain reaction (RT-PCR) which need a sophisticated laboratory. Another alternative that has recently come up is NS1 antigen detection. The present study compared IgM antibody detection with NS1 antigen for the diagnosis of acute dengue in 87 samples. NS1 antigen could be detected with good sensitivity (71-100%) till day 3 of fever, whereas IgM had a sensitivity of 0% to 50% at this time. On day 4 of illness, both the tests had comparative sensitivity. Beyond day 4, IgM antibody detection was superior to NS1. Both these diagnostic modalities were also compared with RT-PCR in 40 acute samples. NS1 detected additional 15 samples, which were missed by PCR. NS1 antigen is an early diagnostic marker that is feasible in a routine diagnostic laboratory.
authors: Department of Virology, Postgraduate Institute of Medical Education and Research, Chandigarh, India. minipsingh@gmail.com
authors: Mini Pritam
authors: MP
authors: Singh
authors: Manasi
authors: M
authors: Majumdar
authors: Gagandeep
authors: G
authors: Singh
authors: Kapil
authors: K
authors: Goyal
authors: Kanwal
authors: K
authors: Preet
authors: Abha
authors: A
authors: Sarwal
authors: Baijayantimala
authors: B
authors: Mishra
authors: Radha Kanta
authors: RK
authors: Ratho
mesh_terms: D000208:Acute Disease; D000956:Antigens, Viral / Q000097:blood*; D015415:Biomarkers / Q000097:blood; D003715:Dengue / Q000175:diagnosis* / Q000821:virology; D042241:Early Diagnosis; D006801:Humans; D007075:Immunoglobulin M / Q000097:blood; D007194:India; D011933:Reagent Kits, Diagnostic; D012680:Sensitivity and Specificity; D017361:Viral Nonstructural Proteins / Q000097:blood*
chemical_list: D000956:Antigens, Viral; D015415:Biomarkers; D007075:Immunoglobulin M; D011933:Reagent Kits, Diagnostic; D017361:Viral Nonstructural Proteins