Rubella IgM antibody determination: comparison of two indirect and two capture commercial enzyme immunoassays.
A new capture ELISA kit (ETI-Rubek-M) for rubella IgM antibody determination was compared with a commercial reverse (Rubenostika IgM) and two indirect ELISAs (Rubelisa M and Rubazyme-M). Of the 89 sera from 38 patients with acute rubella infection, 70 gave identical results with the four assays (78% concordance), 74 were in agreement in the two indirect ELISAs, and 83 concorded in the reverse assays (83% and 93% concordance, respectively). On the whole, ETI-Rubek-M and Rubenostika IgM proved equally sensitive; sensitivity of the indirect ELISA kits was lower, Rubazyme-M being slightly more sensitive than Rubelisa M. Specificity of the two reverse assays was 100%, whereas Rubelisa M and Rubazyme-M showed a specificity of 88.8% and 93.3%, respectively. In indirect ELISAs, false positive IgM results were mainly observed in cytomegalovirus IgM-positive sera from patients recovering from a primary cytomegalovirus infection. Two sequential sera from one of these patients with IgM to cytomegalovirus were found to be true positive for rubella-specific IgM antibody with ETI-Rubek-M, Rubelisa M and Rubazyme-M.
Revello
M G
MG
Virus Laboratory, Institute of Infectious Diseases, University of Pavia, Italy.
Percivalle
E
E
Zavattoni
M
M
Gerna
G
G
D000208:Acute Disease; D000914:Antibodies, Viral / Q000032:analysis*; D003587:Cytomegalovirus / Q000276:immunology; D004797:Enzyme-Linked Immunosorbent Assay; D005189:False Positive Reactions; D006801:Humans; D007075:Immunoglobulin M / Q000032:analysis*; D011237:Predictive Value of Tests; D011933:Reagent Kits, Diagnostic; D012409:Rubella / Q000175:diagnosis*; D012412:Rubella virus / Q000276:immunology*
D000914:Antibodies, Viral; D007075:Immunoglobulin M; D011933:Reagent Kits, Diagnostic; C040901:rubella antibodies