Suboptimal detection of influenza virus in adults by the Directigen Flu A+B enzyme immunoassay and correlation of results with the number of antigen-positive cells detected by cytospin immunofluorescence.
To provide 24-h influenza diagnosis for adults presenting to the emergency department, the Directigen Flu A+B enzyme immunoassay (EIA) was performed in the chemistry laboratory during the night shift. Nasopharyngeal swabs were retested by cytospin-enhanced direct immunofluorescence (DFA; SimulFluor respiratory screen) when the virology laboratory opened. The influenza EIA detected 16 influenza A virus infections, whereas cytospin-enhanced DFA detected 31 influenza A virus infections as well as 3 respiratory syncytial virus, 2 adenovirus, and 1 parainfluenza virus infections. A positive EIA result usually correlated with 50 or more influenza virus cells positive by DFA.
Landry
Marie L
ML
Department of Laboratory Medicine, Yale University School of Medicine, New Haven, Connecticut 06520, and Clinical Virology Laboratory, Yale New Haven Hospital, New Haven, Connecticut 06504, USA. marie.landry@yale.edu
Ferguson
David
D
D000328:Adult; D000956:Antigens, Viral / Q000032:analysis*; D002498:Centrifugation; D019085:Fluorescent Antibody Technique, Direct; D006801:Humans; D007124:Immunoenzyme Techniques / Q000379:methods*; D009980:Influenza A virus / Q000145:classification / Q000302:isolation & purification*; D009981:Influenza B virus / Q000145:classification / Q000302:isolation & purification*; D007251:Influenza, Human / Q000175:diagnosis* / Q000821:virology*; D009305:Nasopharynx / Q000166:cytology / Q000821:virology; D011933:Reagent Kits, Diagnostic
D000956:Antigens, Viral; D011933:Reagent Kits, Diagnostic