Comparison of mumps-IgM ELISAs in acute infection.
BACKGROUND
In Scotland there has been an outbreak of mumps with over 4000 confirmed cases in the last 2 years. As laboratory diagnosis is usually requested on patients with symptoms, a prompt diagnosis early in the illness is required.


OBJECTIVE
To assess the performance of the five different commercial IgM-ELISAs used in Scottish Virus laboratories.


METHODS
The Specialist Virology Laboratory (SVC) Edinburgh distributed a serum panel to all Scottish laboratories that diagnose mumps by IgM-ELISA. The panel consisted of 45 sera from patients with confirmed mumps (date of onset known for 44/45) and 11 sera from patients with alternative diagnoses. Each laboratory performed their own commercial IgM-ELISAs blindly and reported results to the SVC Edinburgh.


RESULTS
Sensitivity ranged from 24% to 51%. Assays performed better on samples taken later than 10 days after onset of symptoms. Specificity was about 82% for most assays.


CONCLUSIONS
The sensitivity of commercial mumps IgM-ELISAs varied greatly. The Microimmune mumps-IgM ELISA had the best overall sensitivity in acute serum specimens. Diagnostic laboratories should be developing the means to perform direct detection of mumps virus for acute presentation and requesting convalescent bloods, if acute blood samples have no detectable IgM.
Krause
Claudia H
CH
Specialist Virology Centre, Royal Infirmary of Edinburgh, Edinburgh EH16 4SA, United Kingdom. Claudia.Krause@luht.scot.nhs.uk
Molyneaux
Pamela J
PJ
Ho-Yen
Darrel O
DO
McIntyre
Paul
P
Carman
William F
WF
Templeton
Kate E
KE
D000328:Adult; D004797:Enzyme-Linked Immunosorbent Assay / Q000379:methods*; D006801:Humans; D007075:Immunoglobulin M / Q000097:blood* / Q000276:immunology; D009107:Mumps / Q000097:blood / Q000175:diagnosis / Q000276:immunology*; D012680:Sensitivity and Specificity
D007075:Immunoglobulin M